RU2243621C1 - Method and device for generating directional and coherent gamma-radiation - Google Patents

Abstract

FIELD: laser engineering; generation of directional coherent gamma-radiation pulse beam.

SUBSTANCE: proposed method includes pumping of active medium which is, essentially, laser rod made in the form of elongated monocrystal cylinder accommodating uniformly disposed nuclei of isotopes of uranium hydride group and hydrogen atoms; monocrystal lattice has relatively parallel crystal planes and shafts of laser rod; the latter functions at the same time as fast neutron moderator, neutron wave shaper, pumping source, and active medium; laser rod is first enclosed in thermal-neutron absorbing metal envelope, then in steel carrying case with junction flanges at its ends; tightly joined and fixed on one of case ends is conical metal plug and tightly fixed on its other end is steel sleeve closed on one end and provided with axial chamber and gate built of symmetrical adjacent radial chambers of which one accommodates first rigidly fixed trinitrotoluene charge with detonator; installed in tandem in axial chamber of sleeve are neutron-absorbing metal plug free to move to second radial chamber of gate, external fast-neutron source in the form of monolithic cylinder and piston arranged for axial displacement over sleeve, as well as rigidly fixed second trinitrotoluene charge with detonator disposed at closed wall of sleeve; critical conditions are set up in monocrystal by initiating chain fission reaction of heavy uranium nuclei by thermal neutrons as end surface of external fast-neutron source comes in contact with that of monocrystal and sequentially explodes first and second trinitrotoluene charges with the result that plug is pushed due to gas pressure to vacant radial chamber of gate while external fast-neutron source and piston are moved in its place; piston uniformly presses neutron source end to monocrystal through its entire surface due to high-force contact and generates neutron wave on monocrystal longitudinal axis followed by emission of coherent and directional gamma-radiation from conical plug.

EFFECT: enhanced flux density and radiation power.

8 cl, 16 dwg

Description

The invention relates to laser technology, and in particular to methods for producing directed and coherent radiation of high energy in the x-ray and gamma-radiation spectral ranges with a high output flux density of gamma rays (10 ²⁴ -10 ²⁵ s ^-1 · cm ^-2 ) and devices for its generation, and is intended to create a system for protecting planet Earth from colliding with space objects that pose a threat to life on Earth (P.P. Kuznetsov. Analysis of traces of the fall of especially large asteroids on the Earth's surface. Report at the seminar “Mal e solar system bodies "in AI RAS on 25.09.2002, at A.V.Zaytsev. Collisions can be expected at any time // Earth and the universe, 2002, №2 March-April). The magnitude of the fluxes (10 ²⁰ -10 ²¹ s ^-1 · cm ^-2 ) of the pumping neutrons in the present invention can be obtained only as a result of a specially formed nuclear explosion. In this case, the laser medium should be excited by pump neutron fluxes (Bushuev V.A., Kuzmin R.N. Problems of creating lasers of the X-ray wavelength range. Problems of the gamma laser, pp. 34-53, M.: Knowledge Society of the RSFSR, 1976; Husain J. Current trends in development of gamma ray lasers. J. Sci. IND RES., V. 49 (8), p. 390, 1990; Baldwin G. Approaches to the development of gamma ray lasers, Rev. Mod. Phys., Vol. 53, No. 4. Part 486, 1981). All existing modern lasers, including a gamma laser, contain three main components: an active medium (element) in which the population is inverted, a device for creating inversion in the active medium (pump system), and a device for providing positive feedback, for example resonator for IR and visible ranges. They also have the ability to concentrate any energy (including light) in space and time (Boreisho A. Lasers: device and action, study guide. St. Petersburg: Mechanical Institute, 1992). These necessary requirements for the creation of a gamma-ray pump with nuclear pumping are fulfilled with a temporal pumping factor of about 10 ^-3 s, and the explosion time of existing nuclear charges is determined at 10 ^-9 s, which excludes the creation of the device under consideration using existing nuclear charges. This contradiction is overcome under the only condition when they increase (stretch) the time of a nuclear explosion to 10 ^-3 s. An increase in the explosion time is carried out with a change in the geometric factor and critical sizes (the critical size is a size comparable to the mean free path of a neutron in a medium at which chain nuclear reactions begin to occur) of a nuclear charge. In ordinary nuclear charges (spherical symmetry), the critical charge size is determined by only one size - the diameter. In this case, the nuclear reaction uniformly covers the entire volume of the nuclear device over a period of 10 ^-8 s. In the case of cylindrical symmetry, the critical charge size is determined by two sizes — the diameter and length of the charge. With this symmetry, the implementation of nuclear fission reactions of heavy nuclei does not occur immediately in the entire volume, but from one of the ends of a cylindrical charge (rod). In this case, the starting (initial) initiation of nuclear fission reactions is carried out from one of the ends using an additional source of fast neutrons based on the existing nuclear reactions. In this case, the seizure by nuclear fission reactions will be heterogeneous, i.e. a kind of reaction wave will appear. The wave of fission reactions will move along the rod with the speed of thermal neutrons obtained as a result of the deceleration of fast neutrons on hydrogen nuclei, and which, in turn, are produced during fission reactions of heavy nuclei, initiate these fission reactions and amplify in turn the wave of nuclear fission reactions by as you move along the core of a nuclear charge. In this case, the explosion time is determined by the critical length of the rod (the length of the nuclear charge at which the fission chain reaction begins) of uranium nuclei and the rate of movement of thermal neutrons, which excite fission reactions of heavy nuclei. Thus, in the region of the fission reaction wave, gamma rays will be emitted, which are born in the process of fission of heavy nuclei, move along the rod to the opposite end and are emitted from its surface into space. Depending on the crystal structure of the rod and the geometrical factor of the active nuclear solid state medium and on the formation of the reaction wave (initiated by the neutron wave), which is created by diffraction scattering of thermal neutrons on the crystal lattice, and thus a coherent gamma radiation wave is formed. All the necessary parameters of the device, under which the conditions for radiation of directed and coherent gamma radiation are fulfilled, are calculated and determined from the standpoint of nuclear physics, quantum electronics, quantum solid state physics and quantum-wave optics of neutrons in solid-state media.

A known method (prototype) of obtaining inverse population (pumping) of nuclear levels in the material of the active medium of a gamma laser to create coherent gamma radiation from a pump source (V.I. Petrik (RU) RU No. 2074469, MKI 6 H 01 S 4/00 , 1997), which includes the use of an osmium 187 single crystal, the conversion of a certain fraction of nuclei to an excited metastable state of the material of the active medium, the creation of an inverse population between the isomeric levels of osmium 187 nuclei, the creation of gamma-resonance gamma-radiation conditions in the active medium material o transition, pumping of the isomeric level by an external source.

A device is known (prototype). X-ray and gamma laser with nuclear pumping from an external source (Edward Teller (US). Laser weapons // Rocket and space technology, No. 16 (1121), April 17, 1981, p.20, Fig. 3), which includes an external nuclear source for pumping the active medium, laser metal rods with a diameter equal to the absorption of x-ray radiation located around the source, solid matter in rods with a high atomic density,

The known method cannot provide an external neutron pumping of nuclear levels by the provided energy source to maintain inverse population, in order to obtain gamma radiation fluxes of the order of 10 ²⁵ s ^-1 · cm ^-2 , as for this, gamma-ray streams will be required that exceed the gamma-ray output streams by several orders of magnitude, and such a source is not indicated in the method. The pump for excitation of nuclei in this method is produced by gamma radiation, in a nuclear explosion, and not by neutrons, which dramatically reduces the output streams of gamma laser radiation, because primary gamma radiation will only be partially absorbed in the active medium of the gamma laser when creating an inverse population of a small fraction of the excited nuclei. In addition, to create an inverse population, it is necessary that there is a coincidence of the energy of the incident gamma quantum with the nuclear transition, accurate to the width of the transition. In this case, such a part of the necessary energy of gamma rays is contained only in a very small fraction of the energy distribution of gamma radiation in a nuclear explosion. Mostly during nuclear fission, gamma rays with an energy of 6–9 MeV fly out. In a nuclear explosion itself, due to the formation of a high-temperature plasma, a continuous spectrum of radiation is emitted in the X-ray range of 10-100 keV. Thus, the output flux of gamma-ray radiation will become even several orders of magnitude lower than the initial flux of gamma-rays from a nuclear explosion. In this case, the necessary energy of the gamma-ray laser radiation should be of the order of 257 keV, and for the spectrum under consideration the radiation intensity at this energy decreases by several orders of magnitude. In this case, only a small part of the output radiation will be used to excite the necessary nuclear levels. In this case, the bulk of the energy of the pump radiation is scattered uselessly. In addition, the proposed method of converting pump energy into directed coherent gamma radiation is not confirmed by any mathematical calculations or experimental results.

The known device uses external pumping of the material of the active medium of a gamma laser by x-ray radiation and gamma radiation of a nuclear explosion. With external pumping, only a very small fraction of the radiation energy is absorbed in thin rods to the depth of their diameter. In this case, radiation in the X-ray range is mainly absorbed, because X-ray absorption length is tenths of mm. The same thickness are taken and metal rods. As a result of such pumping of the active laser medium, radiation is absorbed due to the Auger effect (the process of filling electrons of vacancies in one of the internal energy levels of an atom, Physical Encyclopedic Dictionary, ed. MES, p. 484, 1984). For a short period of time (10 ^-15 s), the upper electrons in a heavy metal atom begin to occupy the liberated level and emit transition quanta from the upper level to the lower level. Therefore, in order to create an inverse population condition at a given atomic level, X-ray pumping fluxes are required, far exceeding modern sources of nuclear explosions. By virtue of the Koster-Kronig effect (a process in which a primary vacancy of an energy electronic level transforms into one of the secondary vacancies belonging to the same shell of a multielectron atom, see ibid.), The emitted quantum transforms as it moves through the electron medium into several quanta of lesser energy in the amount equal to the energy of the original quantum. Thus, the energy of the output gamma ray decreases. This device was tested in the USA, but no coherent radiation was received. However, directional radiation was obtained due to the geometric factor of a long thin rod (string). This pumping method is ineffective in terms of conversion efficiency, since on the one hand, the geometric properties of external pumping are such that the bulk of the radiation energy is not used, and on the other hand, the output radiation is not coherent, and there will be a strong geometric divergence of the output radiation. In that case, if the radiation were coherent, then there was a diffraction divergence, which is several orders of magnitude less than the geometric. Therefore, the values of the output radiation of the laser under consideration, which are hundreds of terawatts, obtained during testing in the USA, are of no practical interest, because with a typical atomic X-ray pump time of 10 ⁻²⁰ s, the output radiation energy at this power will be only 0.01 J. In this device, the output radiation represents only the X-ray range, which corresponds to a quantum energy of 10–100 keV, and this is small part of the full spectrum of a nuclear explosion, as In this case, large losses of pump energy occur also in the emission spectrum. The results obtained on the output radiation from the rod showed that they make up only 0.001% of the x-ray radiation of a nuclear explosion. Thus, the device in question can be called an X-ray laser and, especially, a gamma laser in the light of the operating conditions described above and the output radiation parameters can only be conditionally, and the device itself (prototype) should be considered as a nuclear charge with rods with high atomic density. However, no other devices of this type have been created to date and no such experiments have been conducted. Additionally, it can be noted that in the known method and device there is no single concept, because the method does not have a nuclear pump source, but an active medium of a gamma laser is present, and an active medium is present in the device, but not for carrying out laser processes in the device, but for exciting deep high-energy atomic levels and re-emitting the pump energy into directional radiation due to the influence of geometric factor of the pumped medium. As a result, the considered method and device (of prototypes) are not means of protecting planet Earth from encounters with space objects due to insufficient energy output radiation in both prototypes and the low efficiency of both of them.

A technical achievement of the present invention is the elimination of these drawbacks, increasing the efficiency of the method and device, obtaining directed and coherent pulsed gamma radiation of high power density and energy flow, which are carried out only when combining into a single concept a new method of organizing the gamma-radiation transition of the active medium and source nuclear pumping. The output radiation parameters necessary for the task can be obtained only by combining the nuclear pump source with the material of the active medium of the gamma laser and using neutron fluxes of a nuclear explosion as a pump of the active medium, rather than gamma rays. To implement such a device, it is necessary to manufacture a solid-state rod with subcritical dimensions in the form of a single crystal with a certain direction of intercrystalline planes from non-metallic material, which is a chemical compound of moderator atoms for pump neutrons and heavy atoms of a pump source in an active medium of a gamma laser with a homogeneous distribution of light and heavy cores.

The existing methods for producing powerful energy flows for their use at a distance of about 10 ⁵ km were not considered in technical projects, because were considered not real. Consideration on the one hand of the physical processes of excitation of heavy nuclei and their fission by thermal neutrons from the perspective of quantum electronics, when such processes are determined by analogy with the phenomenon of inverse population of atomic or nuclear levels excited by x-ray or gamma radiation, and on the other hand, the results of studies on the use of new technologies for growing single crystals (Single crystals, their preparation and properties, Proceedings No. 8 of the VNIIM single crystals, Kharkov, 1982; Ryazanov MI Interaction of nuclear radiation single crystals. M: MEPhI, 1979), as well as developments on the growth of new metals and single crystals from hydride compounds of various metals (Tsarev V.A. Low-temperature nuclear fusion, Usp. Fiz. Nauk, vol. 160, vol. 11, 1990), allow to create, based on the materials of the present invention, a source of controlled coherent gamma radiation for its directed generation in outer space. In this regard, the total beam of 10 ^-3 radiation emerging from the combat end of the gamma laser with coherent and incoherent X-ray and gamma-ray quanta moves in space at the speed of light and carries most of the energy of a nuclear explosion. Such a source is capable of protecting planet Earth from any space objects crossing its orbit by repeatedly impacting at the same place on this object from an optimal distance. With this effect, you can either destroy the body of the asteroid, or create conditions for the deviation of its trajectory to a safe distance from the planet Earth, due to the formation of reactive thrust by evaporation of the substance of the asteroid in a given direction.

The technical result is achieved using a method for producing directed and coherent gamma radiation, which includes the use of an osmium 187 single crystal, transferring a certain fraction of nuclei to an excited metastable state of the material of the active medium, creating an inverse population between the isomeric levels of osmium 187 nuclei, creating gamma in the active medium resonance conditions of the gamma-radiative transition with an energy of 257 keV, pumping the isomeric level with an external source, characterized in that as The active medium series uses a single crystal, which consists of a uranium group isotope hydride, which is obtained, for example, in a vacuum heating furnace inside a metal cylinder by crystallization, for which the surface of its inner diameter is covered with a layer of another metal hydride material and a cylindrical single crystal with intercrystalline planes is grown, which are parallel to each other and its axis and, thus, introduce proportionally and homogeneously distribute hydrogen nuclei and nuclei of uranium isotopes groups and as a result combine a nuclear pump source, a moderator for neutrons, a neutron wave shaper and get a homogeneous nuclear reactor in a precritical state (the beginning of chain nuclear fission reactions), which constitutes the active medium of a gamma laser in a single crystal, and metal shells are sequentially put on the outer cylinder diameter , which reflect and absorb thermal neutrons, and a supporting steel casing, one of the ends, which is closed with a conical plug, and additionally attached to the opposite end they connect a glass with a blind end and an axial cavity and a shutter, with radial cavities communicating with each other and hermetically sealed ends, TNT charge is installed in one of them, and a metal tube made of material is coaxially inserted into the common axial cavity of the glass and shutter cavity with a radial movement along the shutter absorbing thermal neutrons, and with axial movement along the glass, an external source of fast neutrons in the form of a monolithic cylinder and a movable piston, and another TNT charge at the blind end of the glass, and Directed coherent radiation of gamma rays, X-rays and neutrons is obtained from a single crystal in the reactor when they create a critical mode of its operation when initiating a chain reaction of fission of heavy nuclei by thermal neutrons at the moment of contact of the end surface of an external source of fast neutrons with the end surface of a uranium hydride single crystal when successively undermine in the radial and axial cavities of the shutter and the glass TNT charges, the gas pressure of which knocks the cork into a free radial chamber, and on it the place is moved by a monolithic cylinder with a neutron source and a movable piston that enhances contact over the entire surface and uniformly presses the ends of the neutron source and single crystal to each other and thereby initiate the start of nuclear reactions of the pump source in the active medium of the gamma laser with subsequent exit from the cylinder end with conical plugs of coherent and directional gamma radiation, which in turn is formed by initiating nuclear reactions by neutrons of a neutron wave moving along single axis of a single crystal. The fission neutrons of heavy nuclei are scattered and slow down to thermal neutrons with a spatially inhomogeneous distribution and initiate a chain reaction of fission of heavy nuclei and the emission of neutrons and gamma quanta of the fission chain reaction. The fast neutrons of the chain reaction of fission of heavy nuclei to thermal neutrons are scattered and slowed down by hydrogen nuclei and coherently scattered neutrons are formed from a portion of thermal neutrons due to reflection on the crystal planes of a uranium hydride single crystal. A directed neutron wave is generated and amplified from coherently scattered thermal neutrons in the direction of the cylinder axis due to processes: initiation of chain fission of heavy nuclei by thermal neutrons, reflection from the hydride layer on the outer surface of the cylinder, and diffraction reflection by crystal planes of a uranium hydride single crystal. They initiate, form and amplify the phase (coherent) wave of the chain reaction of decay of uranium nuclei in a rod from uranium hydride as a result of absorption of neutrons by a neutron wave by heavy nuclei. Initiate, form and amplify directed phase (coherent) waves of neutrons and gamma quanta due to fission of heavy nuclei by neutrons of a neutron wave and a coherent wave of a chain reaction of fission of heavy nuclei. The front of the thermal wave is formed in the rod, which occurs due to the release of energy in the processes of fission of heavy nuclei so that the speed of the thermal wave does not exceed the speed of the neutron wave. The front of the rod’s evaporation wave is formed, which occurs as a result of heat generation so that the speed of the evaporation wave does not exceed the speed of the neutron wave. A wave front of the compression and rarefaction of the rod medium is formed due to the formation of a heat wave front. The directed coherent neutron wave is scattered and partially converted into a neutron wave to initiate and amplify the phase wave of the chain reaction of fission of uranium nuclei, and the rest is emitted from the opposite end of the single crystal cylinder. The directed coherent wave of gamma quanta is scattered and partially converted into an x-ray coherent wave due to Compton scattering on the electrons of the medium and a directed coherent x-ray wave and the rest of the directed coherent flow of gamma quanta are emitted through the opposite end of the cylinder from uranium hydride.

The technical result is also achieved using a device for generating gamma radiation, comprising, an external nuclear source for pumping an active medium, laser metal rods with a diameter equal to the absorption of x-ray radiation, located around the source, a solid substance in rods with high atomic density, for generating gamma radiation , characterized in that it consists of a laser solid-state non-metallic rod of a metal hydride of a uranium group in the form of an elongated cylinder with precritical dimensions diameter and length, in the volume of the lattice structure, in which isotopes of uranium and light nuclei of hydrogen atoms uniformly distributed with concentration in proportion to the chemical compound, which form the crystal lattice of the single crystal in the form of intercrystalline planes parallel to each other and to the axis of the laser rod, is a homogeneous nuclear reactor , which in total consists of a laser rod, which is simultaneously a moderator for fast neutrons, a neutron wave shaper, and a pump source and a laser-active medium, and by its outer diameter the single crystal is enclosed in a thin foil shell consisting of a material reflecting thermal neutrons, for example, lithium hydride, a titanium cylindrical shell and in metal shells consisting of materials reflecting and absorbing fast and thermal neutrons, as well as in a bearing steel casing with connecting flanges at its ends, where a metal plug is sealed and rigidly mounted in a conical shape on one of the ends of the casing, and also rigidly on the opposite end o additionally installed is a steel cup closed from one end, consisting of an axial chamber, and a shutter, consisting of adjacent symmetrical radial chambers, one of which has a TNT charge rigidly mounted, and are sealed and sequentially installed in the axial chamber of the cup: radially moving in the shutter monolithic metal tube made of a neutron-absorbing material and having an axial displacement along the glass an external source of fast neutrons in the form of a movable monolithic cylinder and a movable piston, as well as Another TNT charge is well installed, which is located near the closed wall of the axial chamber of the glass. The cork and the source of fast neutrons are enclosed in steel cylindrical shirts. The cylinder is enclosed in its own metal cup closed from one end from a material that absorbs thermal neutrons, and with its open end directed toward the cork, it is rigidly and hermetically placed in a steel cylindrical shirt.

The invention is illustrated by drawings, where figure 1 shows a variant of the lattice structures of a cylindrical single crystal in the form of crystalline planes parallel to the axis of symmetry of the cylinder (reactor): a - the lattice structure is made in the form of large crystalline planes parallel to the axis of the cylinder; b - the lattice structure is made in the form of a set of individual cylinders with crystalline planes parallel to the axis; c - the lattice structure is made in the form of separate small crystalline planes according to option a and b; figure 2 presents an isometry of a gamma laser device with an axial section, located in the pre-launch (in a critical state) position in space orbit, figure 3 presents an isometric element of a gamma laser device with an axial section at the time of its launch in space orbit upon contact the end face of the active medium of a single crystal with the surface of a fast neutron source, Fig. 4 shows schematically the physics of the process of fission of a heavy nucleus and the formation of a gamma ray upon absorption of a thermal neutron, Fig. 5 shows but schematically the formation of coherent gamma-ray emission as a result of the initiation of fission reactions of heavy nuclei by neutrons of a neutron wave, Fig. 6 shows a diffraction scattering of thermal neutrons on the intercrystalline planes of a single crystal and the formation of a neutron wave, Fig. 7 gives a general physical picture of the development of processes during formation and the output of coherent gamma radiation from a gamma laser single crystal at the time of launch from space orbit: Fig. 8 shows a graph of changes in the intensity of neutrons a wave when moving along the rod as a result of neutron emission due to the chain reaction of decay of uranium 235 initiated by neutrons of a neutron wave, Fig. 9 shows a graph of the dependence of the change in the critical length on the critical radius of a rod from a uranium hydride crystal 235 without a reflector, Fig. 10 shows the dependence of the change in the critical length (cm) on the critical radius (cm) of a uranium hydride reactor 235 with a reflector of lithium hydride 0.05 cm thick, Fig. 11 shows a graph of the dependence of the change on the critical length (cm ) on the critical radius (cm) of a uranium hydride reactor 235 with a 0.1 cm thick lithium hydride reflector, Fig. 12 shows a graph of the dependence of the change in the critical length (cm) on the critical radius (cm) of a uranium hydride reactor 235 with a reflector of lithium hydride with a thickness of 0.2 cm, Fig. 13 shows a graph of the dependence of the intensity (s ^-1 · cm ^-2 ) of nuclear reactions of uranium decay on time (s) over the lifetime of a thermal neutron as a result of initiation of neutron decay reactions from the source to end of the reactor, Fig.14 shows n is a graph of the change in the rate of evaporation of a rod from uranium hydride depending on the length of evaporation of the rod due to the specific energy released as a result of a chain reaction of the decay of uranium nuclei initiated by a neutron wave, Fig. 15 shows a graph of the temperature (thermal wave) of heating of the rod as the neutron wave moves in the reactor from a distance of 10 cm, Fig. 16 shows a graph of the temperature (heat wave) of heating the reactor as the neutron wave moves through the reactor from a distance of 1 cm.

A device for implementing the proposed method consists of a titanium hollow cylinder 1, the inner diameter of which is covered over its entire length by a foil 2, which is closely adjacent to its surface, up to 0.1 cm thick, made of material reflecting thermal neutrons, for example lithium hydride. In the diameter formed by the foil 2, it is also tight to its surface and along the entire length placed by growing a cylindrical single crystal 3 from a uranium group isotope hydride with critical dimensions in diameter and length. A single crystal 3 over the entire volume is a lattice structure of crystalline planes 4 parallel to each other and to the axis of the cylinder 1 (option a), or from separate composite sets of cylindrical elements 5, each of which includes positions 1, 2, 3 (option b), or from individual small crystalline planes 6 (option c) in figure 1. For all variants, the crystalline planes have, for example, the coordinates (1, 0, 0). Positions 1, 2, 3, 4, 5, 6 characterize an independent element of the device as a laser rod 7 with options (a, b, c), which in laser technology and in our case performs the function of the active medium zone of a solid-state laser in the form of a single crystal 3 FIG. .2, 1. The active medium of the laser in the form of a single crystal 3 is combined with its pump source in the form of a hydride of an isotope of an uranium group uniformly placed in the same single crystal 3. Cylindrical cylinders 7 (or the outer diameter of titanium cylinder 1) are tightly and rigidly mounted shell: obolo 8 made of a material that reflects thermal neutrons, such as beryllium, a shell 9 made of a material that absorbs thermal neutrons, such as cadmium, and a steel supporting body 10 with a connecting flange 11. The shells 8 and 9, as well as the body 10, together with a laser rod 7 nuclear reactor 12. From one end, the reactor 12, through the flange 11, is hermetically closed by a removable conical sleeve 13, which determines the combat direction of the laser rod 7, and from the opposite end it is hermetically and rigidly connected to a vertically located closed and having, for example, a rectangular body shape, a shutter 14. Inside the shutter body 14, a through rectangular channel 15 is made along the entire length of its vertical axis, and on the symmetrical walls of the shutter 14, in the direction of the longitudinal axis of the laser rod 7, coaxially to each other, are made through holes 16 and 17, respectively. In the channel 15 symmetrically to the longitudinal axis passing through the center of the holes 16 and 17, as well as with the closure of the body 10 (figure 2) of the reactor 12 with vertical movement along the channel 15, a plug 18 is tightly installed (figure 2). The plug 18 is made of material that slows down and absorbs fast neutrons, for example cadmium with carbon, the plug has its own outer jacket 19 and hermetically closes the holes 16 and 17 (Fig. 2). From the ends of the channel 15 is hermetically closed by two identical, with a common position, removable covers 20, through one of which a TNT charge 21 with a detonator 22 is rigidly installed in the channel 15 and a steel bolt 23 is tightly insulated on the lead-in wires (no positions) on one of the covers 20 To the wall of the valve body 14 (Fig. 3) from the side of the hole 17 (Fig. 2), a hollow cylinder 24 (Figs. 2, 3) is tightly and coaxially aligned with 7, 16 and 17, inside of which it is tight, with axial movement, found: a radioactive source of fast neutrons 25, enclosed in its meta a cylindrical shirt 26 (FIG. 2, FIG. 3) and a pressing piston 27. The open end of the cylinder 24 is sealed through a connecting flange 28 by a removable cover 29, by means of which a second TNT charge 30 with its detonator is rigidly installed in the hollow cylinder 24 under the cover 29 31, with lead wires (they have no positions) and a steel bolt 32 insulating them, which is hermetically mounted on the cover 29. TNT charges and their detonators have independent positions, because they carry a different explosion power and perform various technological functions not related to each other. A radioactive source of fast neutrons 25 is a small-sized (figure 2) mixture of radioactive elements whose nuclei emit fast neutrons under the influence of nuclear reactions with a particle flux of the order of 10 ⁸ -10 ⁹ s ^-1 · cm ^-2 . The device thus obtained is a nuclear-pumped gamma laser, which in terrestrial conditions should be hermetically placed in a metal container with layers that are protected from radiation, which is removed when launched into space orbit. In the present invention, the container is not considered and has no positions.

To determine the positions and in order to describe the physical processes in the laser rod 7 and in the nuclear reactor 12, Fig. 4 schematically and in expanded form shows the space of the crystal lattice 33 with atoms of isotopes of the uranium group 34, for example, uranium 35 with hydrogen atoms 36 embedded in it, forming a chemical compound UH ₆ having a solid state in the form of a single crystal. The crystal lattice 33 consists of atoms of the isotope of the uranium group 34 into which hydrogen atoms 36 are embedded and uniformly distributed. Figures 4, 5, 6, 7 show nuclear particles that participate in the processes of nuclear pumping and initiation of nuclear fission reactions by thermal neutrons 37 s the release of fast neutrons 38, gamma rays 39 (figure 4), fragments of heavy nuclei 40 (figure 4), initiation due to fission reactions of the wave front of chain nuclear reactions 41 (5 and 7) of the front of the heat wave 42, the wave front evaporation of substance 43, front of rarefaction wave 44 and compression of 45 substances, initiation of nuclear fission chain reactions of thermal neutrons 37 with the release of fast neutrons 38 and the formation of fast neutrons 38 on deceleration of hydrogen nuclei on the cores of hydrogen and diffraction scattering on the crystal lattice 33 of thermal neutrons 37, initiating coherent nuclear fission reactions of fission 46 and a neutron wave 47 (FIG. 6), which in turn initiates a wave of chain nuclear reactions 41 and a coherent wave of gamma radiation 48 (FIG. 6). All the processes under consideration are carried out in a single crystal 3, in a crystal lattice 33. The formation and output of directional and coherent gamma radiation 48 from a nuclear-pumped gamma laser is as follows. In order to create a new material of the active medium of the laser in the solid-state phase, for example, in a vacuum heating furnace (does not have a position), a single crystal 3 is grown from a uranium group 34 isotope hydride with foil 2 and titanium cylinder 1 reflecting thermal neutrons 37 and the result is a laser rod 7 with options parallel to the longitudinal axis of the single crystal 3 of intercrystalline planes 4, 5, 6 (a, b, c) (Fig. 1) in the volume of the entire single crystal 3 with a uniform distribution of atoms of the isotope of the uranium group 34 and hydrogen atoms 36 in it. The rod 7 is placed in the shell 8, which reflects thermal neutrons 37, the shell 9, which slows down and absorbs fast neutrons 38, as well as in the supporting body 10, positions 8, 9, and 10 together with 7 form a nuclear reactor 12. From the combat end, the reactor is closed with a removable conical sleeve 13 (figure 3), and from the opposite end it is closed with a plug 18, absorbing thermal neutrons 37 (figure 2). In this case, the fission reaction of the nuclei of the elements of the uranium group 34 does not proceed in the reactor 12. In order to initiate the fission reaction process in the reactor and create a thermal neutron flux 37 in it and, as a result of this, the gamma-ray flux 39 performs the following actions. The existing methods deliver the gamma laser into the calculated cosmic orbit and also, in a known manner of control, bring it to the shock position in the direction of the tip of the conical sleeve 13. The choice of the lesion on the body, such as a comet, and the laser is guided to the selected location by known methods. The start of the reactor 12 should occur at the most remote distance from planet Earth and at the optimal distance from the comet or asteroid. Before starting the reactor 12, a gamma-ray pump with a nuclear pump should be in space orbit in a critical launch mode (figure 2) for a sufficiently long time, for example up to several years. Such a critical trigger mode is provided by a plug 18, which hermetically closes and separates the coaxial through holes 16 and 17. The plug is an obstacle for the penetration of fast neutrons 38 from the radiation source 25 through the jacket 26 into the end face of the single crystal 3. Starting the reactor 12 and, consequently, the gamma laser produced by command, for example, from the Earth by detonating the detonator 22, which in turn produces an explosion of TNT charge 21. In this case, the pressure of the gas blast wave moves the plug 18, for example, into the lower free channel al 15 in the housing of the shutter 14 (figure 2). Almost simultaneously with a delay of 10 ^-3 s, the second detonator 31 is blown up and the TNT charge 30 burnt in the hollow cylinder 24 under the cover 29 is blown up. A radioactive source 25 is moved along the longitudinal axis of the cylinder 24 with the pressure of the gas blast wave 30. Through the hole 17 in the housing the shutter 14 in place of the knocked out plugs 18 install the source 25 and uniformly press the end face of the radioactive source 25 through the through hole 16 to the end face of the single crystal 3 with a movable piston 27 (Fig. 3). As a result of such contact, fast neutrons 38 of a radioactive source 25 penetrate into a single crystal 3, begin to slow down on hydrogen nuclei 36, reach thermal speeds and turn into thermal neutrons 37, are captured by nuclei of isotopes of uranium group 49 and initiate nuclear fission reactions with the release of fast neutrons 38, gamma of quanta 39 and fragments of heavy nuclei 40. Fast neutrons 38 slow down to thermal neutrons 37 and initiate chain nuclear fission reactions, which in turn produce the initiation of a nuclear wave front x reactions 41, the front of the heat wave 42, the front of the wave of evaporation of substance 43, the front of the wave of rarefaction 44 and the wave of compression 45 of the substance, the initiation of chain nuclear fission reactions by thermal neutrons 37 with the release of fast neutrons 38 and the formation as a result of deceleration and diffraction scattering on the crystal lattice 33 thermal neutrons and the formation of a coherent flux of thermal neutrons, or, which is the same, a neutron wave 47, which in turn initiates a wave of chain nuclear reactions 41 and a coherent gamma radiation wave 48 (FIG. .4, 5, 6, 7, 8). A coherent wave of gamma radiation is output from the combat end of the reactor 12 and is directed to the object of influence in a known manner.

The effectiveness of the method and device for generating powerful directional and coherent pulsed gamma radiation 48 is as follows. It is known that the nuclear fission reaction 36 of the nucleus of an isotope of a uranium group 49, for example uranium 235, under the influence of thermal neutrons 37 consists in the fact that a heavy nucleus, having absorbed a neutron, is divided into two almost equal fragments 40. In this case, fission is accompanied by the emission of two or three fast neutrons 38 and at each act of fission, an energy of approximately 200 MeV is released. In addition, during nuclear fission, high-energy gamma-ray 39 of 9-10 MeV and fast neutrons 38 with an energy of 1-2 MeV are emitted. Obviously, the nucleus, for example, of uranium 235 can begin to divide under the influence of its own thermal neutrons 37, which are formed as a result of the same fission reaction, especially since this amount increases by 2-3 times with each fission event. The intensity of the nuclear fission reaction strongly depends on the neutron energy, i.e. the lower the neutron energy, the higher the intensity of the fission reaction. Since the fission reaction occurs at any energies, in accordance with the law of inverse proportionality of the effective cross section to the neutron velocity, the reaction cross section increases sharply as the thermal neutron energy 37 approaches zero. So, for example, for thermal neutrons E = 0.025 eV, the fission reaction cross section is 600 barn. For thermal neutrons, 37 fission, if it occurs, is the predominant process over all other reactions. So, when a thermal neutron 37 is captured, for example, by a uranium nucleus 235, fission occurs with a probability of 0.84. In addition to the fission process, processes of excitation of the uranium-235 nucleus can also occur, followed by the process of emitting a gamma ray. However, such a process occurs at high neutron energies, i.e. for fast neutrons 38. Thus, it is clear that in order to obtain a high intensity fission reaction, for example, of a uranium nucleus 235, it is necessary to slow down fast neutrons 38 of a fission reaction to thermal neutrons 37. In a collision with a hydride nucleus, an isotope of a uranium group 34, for example, uranium-235 , a fast neutron 38 after deceleration can be absorbed by this nucleus or scattered by hydrogen nuclei 36 or, for example, by uranium-235 nuclei and multiply due to the fission reaction at macroscopic scales, which will occupy the material from the isotope hydride uranium group of uranium-34. When moving to macroscopic scales, individual absorption events, summing up, will lead to some absorption of the neutron flux 50, and the total effect of a large number of scattering events will lead to two macroscopic processes - to slowdown and diffusion. The final result of the action of these two processes will lead to the absorption of part of the delayed thermal neutrons 37 and to the diffusion fission process, for example, of uranium-235 nuclei, and therefore to diffuse radiation of gamma rays 39 arising from the decay of uranium nuclei upon absorption of a thermal neutron 37.

Since the main goal of the task is to obtain coherent gamma-ray fluxes 48, rather than diffuse gamma-ray fluxes 39, to solve the problem, it is necessary to obtain coherent fluxes of thermal neutrons 47, i.e. it is necessary to convert the diffusion fluxes of delayed neutrons into coherent fluxes of thermal neutrons 47 (figure 5). The slowing down of neutrons occurs both in inelastic and in elastic collisions. Before a collision with a neutron, the uranium nucleus 235 or the nucleus of an atom of hydrogen 36 is at rest, and after the collision comes into motion, receiving some energy from the neutron. As a result of this process, the neutron slows down. This deceleration cannot lead to a complete neutron stop due to the thermal motion of the nuclei. The energy of thermal motion of the nuclei of a hydrogen atom 36 is of the order of kT = 0.025 eV. Neutrons with this energy are in thermal equilibrium with the medium, such neutrons are called thermal. Simultaneously with the processes of neutron deceleration, processes of absorption and diffusion of neutrons are in progress. Upon reaching a certain specific energy as a result of deceleration, the neutron can be captured by the nucleus and be eliminated from the further deceleration process. For a medium from an isotope hydride of a uranium group 34, for example, uranium 235, the process of neutron deceleration mainly occurs on hydrogen nuclei, and the absorption and diffusion processes mainly occur on heavy nuclei, for example, uranium 235 nuclei. When one slow thermal neutron 37 is absorbed, for example, The fission of a heavy uranium 235 nucleus and the production of 2 or three fast neutrons 38, i.e. neutron moderation and absorption processes are also accompanied by another process — the neutron multiplication process of FIGS. 4, 5. We determine the parameters of the neutron multiplication process as a result of the deceleration of fast neutrons 38 on the nuclei of a hydrogen atom 36 to thermal energies and absorption of thermal neutrons 37, for example, uranium nuclei 235 in the active solid-state zone of gamma radiation, consisting of hydride, for example, uranium 235. Based on the tabular values for the scattering and absorption cross sections of thermal 37 and fast neutrons 38 at the nuclei of uranium-235, hydrogen and eyteriya and average values of the number of neutrons emitted in the fission of 4, 5.

The average number of neutrons emitted in one act of fission of uranium-235 upon capture of a thermal neutron 37

V _t = 2.47.

Fast neutron energy 38 released as a result of a fission reaction, for example, uranium-235 (eV)

E _n = 10 ⁶ .

The average number of neutrons emitted in one act of fission of uranium-235 during the capture of a fast neutron 38

v _b = 2.65.

Uranium-235 fission cross section for thermal neutrons 37 (cm ² )

S _nf = 5.9 · 10 ^-22 .

The sum of the fission and radiative capture cross sections of a uranium-235 nucleus by thermal neutrons (cm ² )

S _na = 6.98 · 10 ^-22 .

The cross section for elastic scattering of thermal neutrons 37 on a uranium-235 nucleus (cm ² )

S _ns = 1.5 · 10 ^-23 .

Uranium-235 fission cross section by fast neutrons (cm ² )

S _bf = 2 · 10 ^-24 .

Fission and radiation capture cross section of a fast neutron uranium-235 nucleus (cm ² )

S _ba = 2.3 · 10 ^-24 .

Radiation capture cross section of a fast neutron by a uranium-235 nucleus

S _bi = 0.3 · 10 ^-24 .

The cross section for radiation capture of a thermal neutron by a uranium-235 nucleus

S _ni = 1.12 · 10 ^-22 .

The scattering cross section of a delayed neutron at the nucleus of a hydrogen atom 36

S _sh = 6.9 · 10 ^-23 .

The cross section for the absorption of a delayed neutron by hydrogen nuclei

S _ah = 1.15 · 10 ^-24 .

Thermal neutron scattering cross section 37 on uranium-235 nuclei

S _su = 1.5 · 10 ^-23 .

Cross section for scattering of a delayed neutron by hydrogen nuclei

S _sh = 6.9 · 10 ^-23 .

The absorption cross section of a delayed neutron by a hydrogen nucleus

S _ah = 1.15 · 10 ^-24 .

We determine the neutron multiplication coefficients in a solid-state mixture of uranium-235 hydride and deuteride and the neutron growth regime due to the chain reaction of fission of 46 uranium nuclei in such mixtures

The average number of secondary neutrons per neutron capture by the fissile nucleus of uranium-235

Y _t = v _t · S _nf / S _na = 2.087822350.

The average number of secondary neutrons per act of capture of a fast neutron 37 by a uranium-235 nucleus

at _b = v _b · S _bf / S _ba = 2.304347826.

Thermal neutron deceleration coefficient 37 on a hydrogen nucleus

p _h = S _sh / S _ah = 60.00000000.

Deceleration coefficient of a fast neutron 38 on a hydrogen nucleus mixed with uranium-235 nuclei

p _hu = S _sh / S _ni = .6160714286.

38 Fast neutron slowdown coefficient on deuterium nuclei mixed with uranium-235 nuclei

p _du = S _sd / S _ni = .1517857143.

The average absorption cross section of thermal neutron 37 in a mixture of hydrogen with uranium-235

S _au = S _ni + S _nf + S _ah = .7031500000 × 10 ^-21 .

Thermal neutron multiplication factor 37 in a mixture of hydrogen with uranium-235

k _n = v _t S _nf p _hu / S _au = 1.276826983.

Thermal neutron multiplication coefficient 37 in pure uranium-235

k ₁ = y _t p _u = .2796190647.

The average absorption cross section of thermal neutron 37 in a mixture of deuterium with uranium-235

S _ud = S _ni + S _nf + S _ad = .7020400000 × 10 ^-21 .

The multiplication factor of fast and thermal neutrons in a mixture of deuterium with uranium-235

k _d = v _t S _nf p _du / S _ud = .3150779463.

The initial number of fast neutrons is 38 (the magnitude of the neutron flux from the ignition source (s ^-1 · cm ^-2 )

N _to = 10 ⁸ .

The number of generations of thermal neutrons 37 during reproduction

n: = 110.

The number of propagated thermal neutrons 37 in a mixture of uranium hydride 235 in the n-th generation (s ^-1 · cm ^-2 )

I _o = N _to k $\genfrac{}{}{0ex}{}{\text{n}}{\text{n}}$ = .621007236910 ²⁰ .

One generation lifetime for slow reactions (s)

t ₁ = 1 · 10 ^-5 .

Total neutron production time for 100 neutron generations for slow reactions (s)

t _p = t ₁ n = 0.0011.

Thus, the calculations performed to determine the multiplication coefficient of thermal neutrons 37 in uranium-235 show that in pure uranium-235 substances the multiplication coefficient is less than unity, i.e. fission chain reactions in pure nuclear active substances do not take place. However, if a complete hydrogenation of uranium-235 with hydrogen and uranium concentrations is performed in proportion to the chemical compound of uranium hydride (UH ₆ ), the multiplication coefficient of thermal neutrons becomes more than unity. For modern nuclear charges, moderation with the help of light nuclei is also used, however, it is not the homogeneous moderator distribution principle in uranium that is used, but heterogeneous, in which the moderator percentage corresponds to the necessary value for moderating the neutron to thermal energies. Moreover, the sizes of such charges become relatively large.

In this case, the homogeneous distribution of the moderator is considered, and it is used not in the form of a compound of hydrogen with oxygen, but in its pure form, which increases the multiplication coefficient of thermal neutrons and changes all other parameters, including the size of the charge. Such a mixture of moderator and active core can be obtained in the form of a chemical compound called uranium hydride (UH ₆ ), which gives wide technological possibilities for creating a fuel cell. Such elements can be produced by pressing from uranium hydride powder or growing uranium hydride single crystals. Estimated calculations show that with an initial fast neutron flux of 38 equal to N _o = 10 ⁸ (s ^-1 · cm ^-2 ), which can be obtained as a result of other nuclear reactions, due to the process of neutron multiplication in solid uranium-235 hydride as a result chain nuclear fission reactions of uranium-235 in a time equal to 10 ^-3 s, the magnitude of the neutron flux 50 increases to N = 10 ²⁵ (s ^-1 · cm ^-2 ). Upon reaching thermal energy (0.25 eV), the thermal neutron 37 begins to manifest wave properties. According to quantum-mechanical concepts, a neutron, like any other particle, has wave properties. These wave properties will now affect the neutron after it is slowed down by a hydrogen 36 atom and when it moves in a uranium hydride crystal, since the de Broglie wavelength l _nu = 0.1 · 10 ^-7 cm is close to the interplanar distance d _uh = 0 in order of magnitude , 27 · 10 ^-7 cm. At this wavelength, the neutron energy has a value in the range of E _n = 0.08-0.25 eV, so that the wave properties are clearly reflected in thermal neutrons 37 and even stronger in cold ones. The influence of wave properties is manifested in the fact that neutron waves 47 scattered by different nuclei begin to interfere with each other, undergo diffraction, refraction, and reflection (including total internal reflection).

If the energy of the thermal neutron 37 in the neutron wave 47 is (erg)

E _t = 8 · 10 ^-14 ,

then at a solid-state concentration of uranium hydride molecules 235 equal to (cm ^-3 )

N _o = 4.7 · 10 ²² ,

the wavelength of the thermal neutron will be equal to (cm)

l _nu = (4π ² h $\genfrac{}{}{0ex}{}{\text{2}}{\text{p}}$ / (2m _n E _n )) ^1/2 = .1110157647 · 10 ^-7 .

The interatomic distance in such a solid-state medium is determined by the expression (cm)

d _uh = (1 / N _o ) ^1/3 = .2770984186 · 10 ^-7 ,

which is called the interplanar spacing in crystal 3 of uranium hydride. Thus, passing through the crystal, thermal neutrons 37, like x-rays, undergo diffraction scattering (Fig. 8). This scattering is manifested in the fact that when a neutron beam enters the crystal, new beams appear that go in a direction different from the original ones (Fig. 8). During the passage of beams of thermal neutrons 37 in the crystal as a result of scattering on hydrogen nuclei, a plane neutron wave 47 is formed (Fig. 7). The nuclei of hydrogen atoms 36, located in a certain crystalline plane, reflect this wave. There are a lot of parallel crystalline planes 33. Neutron waves 47 reflected in each of them interfere with each other. As a result, from the crystal 3 as a whole, the neutron wave 47 will propagate only in the direction in which the waves reflected by different parallel planes begin to amplify each other. For this, the difference in the path of the rays reflected by different planes should be equal to an integer number of half-waves. In the case under consideration, for a rod 7 of uranium hydride, such planes will occur if crystal 3 is grown, for example, with a plane [1.0.0.].

2d _uh sin (ϑ) -ml _mu ,

where d _uh is the interplanar distance, ϑ is the slip angle between the reflecting plane and the incident beam, m is a positive integer called the reflection order. This relation is called the Bragg-Wolfe condition. It is applicable for diffraction by a crystal of waves of any nature, including neutron waves 47. Hence, the slip angle for a given reflection order will be determined by the expression:

ϑ = arcsin (ml _nu / (2d _uh )) = arcsin (.2003182935 m).

In the near diffraction zone, i.e. for m = 1, the slip angle is approximately ϑ = 0.2 rad.

The main parameter characterizing the processes of neutron scattering in crystal 3 is the scattering length, which is used to describe the s-wave scattering of incident low-energy neutrons in interaction with the nucleus. In the Born approximation, the differential scattering cross section does not depend on the scattering angle and energy, so long as the condition that the neutron wavelength exceeds the scattering length can be considered fulfilled. The scattering length is determined from the value of the elastic scattering cross section of the thermal neutron 37 on the nuclei of hydrogen atoms 36 or uranium atoms 34 in uranium hydride.

S _sh = 6.9 · 10 ^-23 ,

the total amplitude of scattering of thermal neutrons 37 on the nucleus of a hydrogen atom 36 in uranium hydride (cm)

a _nh = (S _sh / 4π)) ^1/2 = .2343849520 · 10 ^-11 .

Based on the fact that a crystal contains N nuclei, the total cross section for scattering of thermal neutrons in an ensemble of N nuclei of a crystal will be determined by the expression

where a _k (n) is the amplitude of coherent neutron scattering for the n - plane. Assuming that the amplitude of coherent scattering is the same for each plane of reflection of the neutron flux, we obtain the expression for the cross section of coherent scattering in the form:

where x (n) is the radius vector of the lattice nodes, K is the radius vector of the reciprocal lattice. This sum vanishes if the product K.x (n) is not an integer multiple of 2π for all n. Thus we come to the Bragg condition, which is satisfied when the wave vector of the scattered particle K is equal to one of the reciprocal-lattice vectors G (Figs. 6, 7). Let us estimate the sum over the lattice for the case of a one-dimensional crystal with a lattice constant equal to d _uh , and then generalize the result to the case of three measurements. Let the number of uranium hydride crystal molecules be N; the coordinate of the n-node x (n) = n · d _uh , where n is an integer that takes one of the values in the range from 0 to N-1.

Then the probability that this crystal atom will have a scattering amplitude equal to x (n) will be equal to:

or, which is the same, this expression can be represented as:

where K: = _{1/1 nu} is the wave number for the neutron as a wave (cm ^-1 )

In the case of three measurements, we finally obtain the expression for the cross section for coherent neutron scattering on the lattice of crystal 3 of uranium hydride in the form:

for the number of atoms in one crystal cell equal to

N = 3,

section of coherent scattering of thermal neutrons 37 in a uranium hydride crystal (cm ² )

S _sk = .4437117262 · 10 ^-22 .

The refractive index of thermal neutrons 37 at the boundary of two media of uranium hydride and vacuum will be determined by the value

n _p = 1-4π l _nu a _nh N _o / (2π) = 0.9999728464.

Hence, the critical slip angle at which full internal reflection begins in the crystal plane for the neutron beam and the coherence condition for the neutron wave is preserved 47

ϑ _k = 2arccos (n _p ) = 0.01473871715.

Consider the intensity of the neutron wave at some point after their diffraction scattering on the crystalline plane 33 of crystal 3 (figure 5, 8). The oscillations created by the elementary zone (m = 1) with the x coordinate at this point, the position of which relative to the crystal plane is determined by the angle ϑ, can be represented as:

The resulting oscillation created at the point under consideration by the entire open area of the wave surface can be found if the distance between two crystal planes is integrated over the width

where the resulting oscillation is determined by the expression

U _h = U _o (sin (π d _uh sin (ϑ) / l _nu ) l _nu / (π d _uh sin (ϑ)),

From this it is seen that the amplitudes of the vibrations arriving at different points in space will have maximum values provided that Bragg-Wulf's neutron scattering on the crystal planes 33 of FIG. 6 is satisfied.

For a given value of the thermal neutron flux 37, which are formed as a result of neutron multiplication of the fission chain reaction, for example, uranium-235 nuclei,

I _about = 0.621007236910 ²⁰ s ^-1 cm ^-2

we determine the coherent neutron flux of the neutron wave 47, which is formed as a result of scattering of thermal neutrons 37 on the nuclei of the crystal lattice 33 of uranium hydride within the slip angle relative to the crystalline planes of single crystal 3 of uranium hydride for maximum intensity at m = 1 Bragg-Wulff condition (coherent thermal scattering neutrons on the crystal lattice) (s ^-1 · cm ^-2 )

m = 1.

I _g = I ₁ (sin (d _uh sin (ϑ) / l _nu ) l _nu / (π sin (ϑ))) ² , where I ₁ = I _o ϑ S _sk / S _sh is the thermal neutron flux 37 (s ^-1 · cm ^-2 ), reflected from all crystalline planes 33 (6, 7) at an angle of reflection.

Hence, the numerical value of the total neutron flux of the neutron wave 47 as a result of diffraction scattering of thermal neutrons 37 on the crystal planes of uranium hydride in accordance with the Bragg-Wulf conditions is

I _g = .5885836057 · 10 ¹⁸ s ^-1 · cm ^-2 .

This refers to the neutron flux 50, which occurred at a given time. With further movement through the medium, the magnitude of this flux will increase due to neutron emission as a result of the fission chain reaction (Fig. 4).

All other thermal neutrons 37, which do not fit into the critical slip angle and, due to diffusion, are transferred to other regions of the medium, where as a result of isotropic scattering on the nuclei of hydrogen atoms 36 or uranium-235 atoms, they can have any angle relative to the crystal plane 33, including less critical slip angle. It is also necessary to take into account the limited size of the medium and the boundary conditions at the boundary of the medium, which can also change the position of the direction of neutron motion relative to the crystalline plane 33. In addition, the limited size of the active medium creates a condition for a quantitative change in neutrons, i.e. they can be eliminated as a result of departure abroad of the medium, as well as due to absorption by uranium nuclei.

Neutron wave 47 is formed within the deceleration length of a fast neutron 38, which is determined from the length of neutron scattering by nuclei of hydrogen 36 and uranium

l _s = 0.69 cm

and transport length for thermal neutrons 37 in uranium-235 hydride

l _t = 0.49 cm

and equal at E _n = 2 · 10 ⁶ - the energy of the fast neutron 38 (eV) and the energy Eo: = 0.02 - thermal neutron 37 (eV) the length of the deceleration

L _s = (l _s l _t ln (E _n / E _о ) / 3.) ^1/2 = 1.440836812 cm.

All other processes that determine the absorption of neutrons by uranium nuclei, leading to the fission of uranium-235 nuclei, where

l _a = 1 / (7 · 10 ^-22 · No) = 0,03039513678

- fission length of uranium-235 by a thermal neutron 37 when propagating in uranium-235 hydride

l _f = 1 / (5.9 · 10 ^-22 · N _o ) = 0.03606202667 cm.

and diffusion length of thermal neutron 37 in uranium hydride 235

L _d = (l _t l _a / 3.) ^1/2 = 0.07045948489 cm.

have very short lengths compared with the process of deceleration of fast neutrons 38. This means that neutron wave 47 is formed approximately within 1.5 cm, the intensity of which increases as the gamma laser moves through the active nuclear medium due to the multiplication of neutrons as a result of a nuclear chain reactions, which in turn are initiated by neutrons of a neutron wave 47. Neutron wave 47 is a wave surface in which neutrons oscillate in one phase (spatial coherence), and which moves with a velocity equal to the speed of a thermal neutron. Neutrons in a neutron wave 47 are interconnected via an intercrystalline medium and therefore all processes that will be associated with neutrons of a neutron wave 47 will in turn have the property of spatial coherence, i.e. will occur almost simultaneously (within the characteristic times of the ongoing process) over the entire surface of the neutron wavefront. This means that if the neutrons of the neutron wave 47 are absorbed by the uranium nuclei 235, then this absorption process and then, accordingly, the subsequent process of fission of uranium nuclei will occur within the time limits of these processes over the entire wave surface almost simultaneously (Figs. 4, 5). But this in turn means that gamma radiation as a result of the fission process of the uranium nucleus during fission will also occur almost simultaneously along the entire wave surface (Figs. 5, 7), i.e. gamma radiation 39 will also be of a coherent nature, provided that the fission time of the uranium nucleus 235 is shorter or comparable to the lifetime of a thermal neutron. If the thermal neutron velocity 37 is

V _n = 1 · 10 ⁵ cm / s,

fission uranium-235 fission cross section 37

S _fn = 5.8 · 10 ^-22 cm ² ,

then the characteristic fission time of the uranium-235 nucleus as a result of thermal neutron capture 37 is

t _fn = (4.7 · 10 ²² S _fn V _n ) ^-1 = .3668378576 · 10 ^-6 ,

and the lifetime of a thermal neutron in uranium-235 hydride

T ₀ = 1.5 · 10 ^-5 s.

From where it is seen that the alleged condition holds. Hence, knowing the magnitude of the coherent neutron flux 47, one can determine the intensity of coherent gamma radiation 48, which is initiated by neutrons of the neutron wave 47. Thus, the intensity of coherent gamma radiation 48 during fission of the uranium-235 nucleus as a result of capture of thermal neutron 37 from the neutron coherent wave 47 at diffraction reflections on n planes will be determined by the expression

W _g = I _g S _fn N ₀ : =. 2495066914 · 10 ²⁰ s ^-1 · cm ^-3 .

In the process of movement of a neutron wave 47 through the medium of a single crystal 3, the intensity of the neutron wave 47 will increase due to neutrons that arise as a result of a chain reaction of fission of uranium nuclei. Some of these neutrons will go beyond the limits of the reactor medium 12. However, at this stage of the calculation, this is not taken into account. We construct the equation for the multiplication of neutrons based on the fact that the length of the deceleration of fast neutrons 38

L _s = 1.5 cm

and the neutron multiplication factor is

k _n = 1.27.

The differential equation for the intensity of neutron multiplication in a neutron wave due to the chain reaction of uranium fission initiated by the neutron wave 47. If we take the intensity W _g as the initial value, then the change in the neutron intensity will be described by an equation of the form:

The change in the neutron intensity in the neutron wave 47 when moving along single crystal 3 of uranium hydride is determined by the expression:

W (x) =. 249506691410 ²⁰ exp (0.18x)

On Fig shows that as the neutron wave 47 moves along the rod 7, the wave intensity increases and quite strongly.

To determine the total intensity of coherent gamma radiation 48, it is necessary to determine the characteristic dimensions of a nuclear-active medium or, what is the same, determine the critical sizes of a single crystal 3 of uranium hydride, at which an avalanche fission process of uranium-235 nuclei occurs. In accordance with the requirements of the conditions of the problem, it is necessary that the motion of the neutron wave 47 be directed only in one direction, i.e. the movement of the neutron wave must be one-dimensional. This can be done only if the neutron wave is initiated in the rod 7 from uranium hydride, and its initiation is carried out from the end, i.e. therefore, the initiation of a chain reaction of fission of uranium nuclei also needs to be carried out from the end. To initiate a fission chain reaction in the rod 7, a neutron source generator 25 is used, which is a kind of neutron detonator to start the chain reaction from the end of the rod. To date, the control of a spatially heterogeneous process of the beginning of a chain reaction has not been carried out. In this case, such a process of starting a chain reaction can be carried out in a rod of uranium-235 hydride. With such an initial spatially inhomogeneous fission chain reaction (nuclear fission chain reaction wave 41, initiated by the thermal neutron wave 47), it is possible to increase the time of the complete chain reaction process, as well as obtain directional stable neutron radiation and gamma radiation 39, which are emitted during uranium fission . The directivity of radiation arises due to the geometric factor of the medium in which the process of uranium fission occurs under the influence of thermal neutrons 37 moving along the string. The most common types of reactions can be used as a neutron generator: (Ra - alpha-Be) - a source with the Be9 nuclear reaction (alpha, n) C12, which results in 10 ⁸ neutrons per second per gram Ra with energies of 2 MeV or more that is quite enough for the process of initiating a chain reaction or (Po - alpha - Be) - with the same nuclear reaction (Fig.4, 5, 7).

Thus, it is clear that in order to accomplish this task it is necessary to determine the critical dimensions of a homogeneous solid-state single crystal 3 of cylindrical uranium-235 hydride, i.e. determine the radius of the rod 7 and the length of the rod 7. First, we critically determine the dimensions of the rod 7 without a reflector on the outer surface and compare them with the American data obtained during the test. To determine the parameters, we use the diffusion equation according to the theory with one group of neutrons. For the given expression “Laplacian" for uranium-235 hydride

and _h = (k _n -1) / (L $\genfrac{}{}{0ex}{}{\text{2}}{\text{d}}$ + k _n L $\genfrac{}{}{0ex}{}{\text{2}}{\text{s}}$ ) = 0.1042319754

neutron migration lengths in uranium-235 hydride

M: = (L $\genfrac{}{}{0ex}{}{\text{2}}{\text{in}}$ + L $\genfrac{}{}{0ex}{}{\text{2}}{\text{s}}$ ) ^{l / 2} : = 1.442558580.

We obtain the differential diffusion distribution equation for neutrons in uranium-235 hydride

Equation solution

N (r, z): = а _h cos (a _z z) BesselJ (0, a _r r).

From the boundary condition for the cylindrical element of uranium-235 hydride

BesselJ (0, a _r (r + 0.83 / 3 ^1/2 )) = 0

it is necessary to determine the root, which is equal to

and _r (r + 0.83 / 3 ^1/2 ) = 2.404825558.

From here we determine the “Laplacian" by radius

a _r = 2.405 / (R + .83 / (3 ^1/2 .)),

Laplacian in height

a _z = π / L ₁

and the full Laplacian

and _h = (π / L ₁ ) ² + 5.784025 / (R + 0.4792007233) ² .

This makes it possible to determine the ratio between the critical dimensions of the length and radius of the reactor 12 from uranium-235 hydride

L ₁ = π (R + 0.48) / (0.104 (R + 0.48) ² -5.784) ^{l / 2} .

From figure 9 it is seen that the critical dimensions determine the cylinder, in which the length and radius can be different. We find the minimum value of the radius of the cylinder based on the condition of the infinite length of the cylinder

R _o : = (5.784 / 0.104) ^1/2 -0.48 = 6.977572301 cm.

To determine the final length, we take the radius equal to

R _c = 6.99;

substitute this value for the radius in the expression

L _c = 3.14 (R _c +0.48) / (0.104 (R _c +0.48) ² -5.784) ^{l / 2} = 168.8665437.

If we compare the dimensions of the rod 7 with the American data, then only the length coincides, while the radius in this case exceeds three orders of magnitude. This is understandable since the radius for the American tests was taken on the basis of other physical considerations, namely the absorption of gamma radiation in the medium.

To solve the problem in the present invention, it is necessary that the length is much greater than the radius, and the radius, in turn, should be much less than the obtained value of the critical value of the radius. Only under these conditions, the geometric factor of the rod 7 will determine the condition of the directivity of the neutron wave 47 and the one-dimensionality of motion. To solve this problem, it is necessary to take advantage of a change in the boundary conditions on the lateral surface of uranium hydride cylinder 3, assuming that the lateral surface is covered by a substance from which the reflection of neutrons generated in the medium occurs. The substance should be such that the reflection would be maximum (Fig. 7). Beryllium is usually used for this. However, there may be some other material, such as hydrogen or deuterium. We determine the necessary parameters characterizing the propagation of neutrons in a system of hydrogen nuclei with a solid density. All the main parameters of neutron propagation in these media are given by the following values:

thermal neutron diffusion coefficient in uranium-235 hydride

D _h = L _d V _n / 3; = 2348.649496 cm ² / s,

neutron diffusion coefficient on deuterium nuclei

D _d = V _n I _sd /3=95999.99999 cm ² / s,

thermal neutron diffusion length on deuterium nuclei

L _dd = (D _d t _ad ) ^1/2 = 135.2955386 cm,

neutron scattering length at the nuclei of a hydrogen atom

l _s = 0.68 cm

cross section for the absorption of a delayed neutron by hydrogen nuclei

S _ah = 1.15 · 10 ^-24 cm ² ,

neutron absorption length in a system of hydrogen nuclei

l _ah = 1 / (S _ah N _o ) = 18.50138760 cm,

thermal neutron lifetime in such a system of hydrogen nuclei

T ₁ = l _ah / V _n = .0001850138760,

thermal neutron lifetime in a system of deuterium nuclei

T _1c = l _fv / V _t = .1906758621,

diffusion coefficient of a neutron in a system of hydrogen nuclei

D _d = V _t l _s /3=22666.66666,

neutron diffusion length in a system of hydrogen nuclei

L _h = (D _d1 T ₁ ) ^1/2 == 2.047839802,

neutron diffusion length in a system of deuterium nuclei

L _h1 = (D _d T _1d ) ^1/2 = 135.2955386,

neutron moderation length in a system of deuterium nuclei

L _sd = (l $\genfrac{}{}{0ex}{}{\text{2}}{\text{sd}}$ ln (E _n / E _o ) / 3.) ^1/2 = 7.136490602.

In the general case, the system of diffusion equations for neutrons propagating in uranium hydride with a reflector will look as follows:

Boundary conditions at the boundary of a uranium-235 hydride string with a reflector N1 (R, z) = N2 (R, z);

where p is the ratio of the diffusion coefficients of neutrons in the string and in the reflector of hydrogen nuclei

p = D _d1 / D _h = 9.650936293,

as ₁ is the thickness of the reflector.

Consider the solution of this system for a reflector with hydrogen. Solutions that determine the spatial distribution of neutrons in uranium hydride and in the reflector will be sought by the method of separation of variables. The neutron distribution in uranium hydride is presented in the form:

N1 (r, z): = F1 (r) Z1 (z),

where the distribution of neutrons along the length takes place

Z1 (z): = cos (a _z z)

and in radius

F1 (r): = Abesse1L (0, a _r r).

The neutron distribution in the reflector is represented as:

N2 (r, z): = F2 (r) Z2 (z),

where the neutron distribution along the length is presented as

Z2 (z): = cos (a _z Z).

In this case, the “Laplacian" is equal in length

and _I = π / L,

and in radius

and _k = 2.405 / R.

In this case, the radial distribution of neutrons in the hydrogen reflector is determined from the equation

whose solution is the expression

F2 (r): = BBesselI (0, sr) + CBesselK (0, sr);

with “laplacian”

and _h = a $\genfrac{}{}{0ex}{}{\text{2}}{\text{z}}$ + a $\genfrac{}{}{0ex}{}{\text{2}}{\text{r}}$ = (π / L) ² + 5.784025 / R ² ;

s = (1 / L $\genfrac{}{}{0ex}{}{\text{2}}{\text{h}}$ + (π / L) ² ) ^1/2

and the radius of the reactor with a reflector (cm)

R ₁ = R + s ₁ .

The functions that are substituted into the expression for the condition for determining the ratio of the critical length and radius for the reactor are:

J2: = - BesselK (0, sR ₁ ) / BesselI (0, sR ₁ );

J1: = diff (BesselK (1, s · R), R);

a condition that determines the relationship between the length and radius of a string of uranium-235 hydride with a reflector, obtained by substituting the solution of the equations in the given boundary conditions

K _r = (2.4BesselJ (1,2.4 / R) / (RBesselJ (0,2.4 / R)) - (sD _dl (Jl + J2BesselI (1, sR)) / (D _h ((BesselK (0, sR) -J2 BesselI (0, sR)))) + l / s ₁ )).

As a result of a numerical calculation from this condition, which are shown in FIGS. 10, 11, 12, the relations between the critical lengths and radii for the reactor 12 were made of uranium-235 hydride with a reflector for different thicknesses of the reflector, for example, lithium hydride. The results obtained show that a uranium-235 hydride rod without a neutron reflector has critical radius sizes of the order of R _cr = 7 cm. These rod sizes are too large to form a plane neutron wave 47. As a result of evaluative calculations to determine the material for neutron reflection, as well as determination of the critical dimensions of the rod 7 of uranium hydride with this reflector, it was found that the optimal material for such a reflector is hydrogen 34, the critical size of the rod below ilsya to a radius R = _kr 1-3 cm. When the thickness of the reflector coating 2 (1) of lithium hydride in the range of 0.05-0.2 cm. For such a reflector can use metal foil 2 (Figures 1, 2 ), for example from hydrogenated lithium, or hydride of some other light metal. The length of the string is taken slightly less than critical (L <L _cr = 20-150 cm) so that the uncontrolled process of the chain reaction does not start in advance. As a result of fission of uranium-235 nuclei during the capture of thermal neutrons 37, fragments of nuclei 40 arise with a total energy of about 200 MeV = 2 · 10 ^-11 J.

Fast neutrons generated by the neutron detonator 25 from the end surface of the rod 7 slow down in the hydrogen medium of hydrogenated uranium-235 to a thermal speed, gradually turning into a neutron wave 47 moving at a speed of V _n = 10 ⁵ cm / s and due to their initial spatial heterogeneity distributions in the rod are captured by uranium nuclei, thus creating a spatially inhomogeneous distribution of the chain reaction of fission of uranium-235 nuclei (wave front of nuclear fission reactions of nuclei), resulting in spaces continuously inhomogeneous concentration distribution of fission fragments 40 with energy E _o = 200 MeV, which cause warming up of the wave front 42 of the rod 7, moving on a medium with a certain velocity. Let us determine the parameters of the process of occurrence of a heating wave 42 based on the release of fission energy of uranium-235 as a result of absorption of a thermal neutron 37 of a neutron wave 47. First, we determine the amount of release of thermal energy at the end of a single crystal 3 of uranium hydride, which arises as a result of the action of a neutron source 25 (neutron detonator) when the surface of the source 25 approaches the surface of the end face of the reactor 12. The neutrons emitted by the source 25 begin to slow down in the medium of the reactor 12 and when thermal energy is reached absorbed by uranium nuclei. The effective absorption cross section of thermal neutron in uranium-235 is determined by:

S _au = 6.9 · 10 ^-22 cm ² .

With the known concentration of uranium-235 atoms in the reactor 12, we determine the absorption length of the thermal neutron 37 in uranium-235.

l _au = 1 / (S _au N _u ) =. 03083564600.

Hence, with the known value of the thermal neutron velocity 37, we determine the average lifetime of one generation of neutrons in slow reactions

T _m = l _au / V _n = 0.1541782300 · 10 ^-6

and at a known value, the neutron multiplication coefficient in uranium-235 hydride is determined by the characteristic fission reaction time in uranium-235 hydride

t _m = T _m / (k _n -1) = 0.5710304815 · 10 ^-6 .

Knowing the magnitude of the energy of the fission fragments of the uranium-235 nucleus and the magnitude of the initial intensity of the number of neutrons emitted by the neutron detonator at the end of the rod

W _o = 1. · 10 ¹⁰ s ^-1 · cm ^-3

you can build a differential equation to determine the change in the energy released in the end of the reactor due to fragments of the uranium nucleus 40 as a result of a chain reaction of fission of uranium-235 nuclei, which are initiated as a result of neutron absorption of source 25,

The solution of a differential equation with initial conditions determines the intensity of the released energy due to the number of fission of uranium-235 nuclei as a result of thermal neutron capture 37

W (t): = W _o exp (t / t _m)

Thus, we find that the energy released at the end of the crystal 3, which is initiated by the neutrons of the neutron detonator 25, is equal to an expression of the form:

W (t): = 10 ¹⁰ exp (0.175122 · 10 ⁷ t)

Numerical calculations of changes in energy intensity depending on the propagation time of a neutron wave 47 along a rod are shown in FIG.

From here one can determine the value of the specific intensity of energy released during time t as a result of the chain reaction of fission of uranium-235 nuclei

Q (t): = W (t) E _o : = 0.2 exp (.1751220000 · 10 ⁷ t) W / cm ³ .

During the lifetime of a thermal neutron, one can determine the intensity of the number of decays of uranium nuclei, i.e. at t = T _o we get the value

W ₁ = 10 ¹⁰ exp (26.2683) = 0.239064684810 ²² s ^-1 cm ^-3

Hence, on the absorption length of a thermal neutron, it is possible to determine the magnitude of the flux of the number of neutrons 50, and hence gamma radiation 39

I _o = W ₁ l _au = 0.7371713992 · 10 ²⁰ s ^-1 · cm ^-2 .

The specific intensity of the absorbed energy during the lifetime of a thermal neutron, or, which is the same thing, the specific intensity of the absorbed energy in a string of uranium-235 hydride, is

Q _o = 4.78 · 10 ¹⁰ W / cm ³

Thus, the flux of absorbed energy of the fission fragments of the uranium nuclei 40 will be equal to

q _o = Q _o l _au = 0.1473943879 · 10 ¹⁰ J / s · cm ² .

Let us now consider the thermal processes that will occur in the reactor as the neutron wave 47 moves through the reactor body, which occurs during the initiation of the fission chain reaction and is initially initiated by the neutrons of source 25 at the end of the reactor. For this, we introduce the main parameters of those physical processes that will be accompanied by the absorption of energy from the chain reaction of uranium fission in the reactor. These include: specific evaporation energy of solid uranium hydride

Q _i = 1 · 10 ⁵ J / cm ³ ,

L _s = 1.5 cm is the deceleration length of fast neutrons,

k _n = 1.27 is the neutron multiplication coefficient in the neutron wave 47 when moving through the reactor 12. The specific intensity released during the chain reaction of uranium fission due to the movement of the neutron wave 47 through the reactor 12 is determined by the expression

Q (x): = Q _o exp ((k _n -1) x / L _s ): = 0.478 · 10 ¹¹ exp (0.18x).

Accordingly, the neutron flux of the neutron wave 47 will increase with the movement of the neutron wave in the reactor 12 according to the law

q (x): = q _o exp ((k _n -1) x / L _s ) = 0.147394387910 ¹⁰ exp (0.18x)

The initial velocity of the front of the evaporation wave 42 of solid uranium along rod 7 of uranium-235 hydride

V _e = q _o / Q _i = 14739.43879 cm / s.

As long as the speed of the evaporation wave 42 is small compared with the speed of the neutron wave, the intensity of the neutron wave 47 in intensity will increase as you move through the reactor 12. When comparing these speeds, a condition will arise for the destruction of the neutron wave, and therefore the coherence condition will also cease to exist , which, naturally, will lead to the diffuse propagation of gamma rays 39, which are emitted at the moment of fission of uranium nuclei

V (x): = q (x) / Q _i = 2456.573132 exp (0.18x) (cm / s)

Numerical calculations to determine the speed of the evaporation wave 42 of the rod 12 as a result of the energy released as a function of distance are shown in Fig. 14.

k _t = 2.5 · 10 ⁵ W / (cm · deg) is the high-temperature thermal conductivity of evaporated uranium at a temperature of 5000 ° С;

c _t = 10.1 J / (g · deg) is the heat capacity of evaporated uranium at a temperature of 5000 ° C;

p ₀ = 18 g / cm ³ - the density of the evaporated uranium. The differential equation of motion of a wave of energy of evaporation of a string under the action of energy absorption as a result of a chain reaction of fission of uranium nuclei initiated by thermal neutrons is given in the form:

Substitute all the values of the parameters of the medium and the process of nuclear fission and consider the differential equation for the process of energy release in the rod in the linear approximation

The solution to this equation can be represented as:

T (x) = 5007.6 exp (0.18x) -5007.6 exp (-11.67x).

The change in the temperature of the rod 7 over the distance as a result of the released energy during the passage of the neutron wave 47 is shown in Fig.15, 16.

In this case, the initial temperature of the heating of a rod of uranium hydride in the energy absorption region as a result of the initiation of a chain reaction of fission of 46 uranium nuclei with thermal neutrons 47

T _x = q _o / (r _o c _t V _e ) = 5050.5.

As a result, the following parameters can be calculated: the initial velocity of the front of the heat wave 41 through a cold medium moving along the string as a result of absorption of the energy of the fission reaction of uranium nuclei:

V _t = (k _t / (p _o c _t T _m )) ^1/2 = 29864.93248 cm / s;

kinetic energy of uranium atoms evaporated by the rod as a result of heating to a temperature of 5050 ° C (erg):

Et _t = v $\genfrac{}{}{0ex}{}{\text{2}}{\text{e}}$ m _a / 2 = 5 · 10 ^-13 ;

speed of vaporized uranium atoms:

V _i = (2E _t / (2.35 · 10 ^-22 )) ^1/2 = 65232.80730 cm / s;

vapor density of uranium-235 atoms:

p ₁ = p _o V _e / V _i = .04067123725 g / cm ³

and vapor pressure of vaporized uranium atoms

P ₁ = p ₁ V $\genfrac{}{}{0ex}{}{\text{2}}{\text{i}}$ 10 ^-7 / 2 = 8.653454730 J / cm ³ .

At the same time, the speed of the sound wave in solid uranium.

V _s = 1 · 10 ⁵ cm / s

Thus, it is seen that the neutron wave 47 is ahead of the speed of all other accompanying processes that could destroy the neutron wave, which in turn initiates the chain reaction wave of fission of 41 uranium nuclei in the reactor as it moves through the reactor, and therefore, initiates radiation gamma rays 39. In order to determine the flux of coherent gamma rays 48 initiated by the neutrons of the neutron wave 47, it is necessary to first determine the concentration of neutrons in the wave. For a given velocity of the neutron wave 47, equal to the thermal velocity, and the known magnitude of the neutron flux in the neutron wave

I _o = 0.73 · 10 ²⁰ s ^-1 · cm ^-2 ,

the neutron concentration in the wave is equal to:

N _n = I _o / V _n = 0.73 · 10 ¹⁵ cm ^-3 .

The same concentration of coherent gamma rays 48 will be emitted during the coherent excitation and fission of heavy uranium nuclei upon absorption of neutrons by a neutron wave 47 of FIGS. 6, 7, i.e. the concentration of coherent gamma rays 48 will be equal to the value (cm ^-3 ):

N _gk : = N _n

Since gamma quanta 39 move in space at the speed of light, the flow of coherent gamma quanta 48 generated by the process of fission of uranium 46 will be equal to

I _og = N _gk3 · 10 ¹⁰ = 0.219 · 10 ²⁶ s ^-1 · cm ^-2 .

As you move through the reactor, the intensity of the neutron wave 47 increases due to the initiation of a chain reaction of fission of 46 nuclei and, accordingly, the multiplication of neutrons (s ^-1 · cm ^-2 ):

I _g (x): = I _o exp (0.18x) = 0.73 · 10 ²⁰ exp (0.18x).

The generated gamma quanta 39 in the solid state medium of uranium hydride naturally begin to move in the same medium. This motion in this medium can lead to a weakening of the flux of coherent radiation of gamma rays 48. At an energy of 8-10 MeV, the processes of braking of gamma rays and energy loss are most effective due to the processes of braking on electrons (does not have a position) of the medium. Other processes, such as the photoelectric effect and the formation of an electron-positron pair, can be ignored due to their low efficiency. The average energy transferred from the gamma quantum 39 to the electron (does not have a position) is comparable in order of magnitude with the energy of the gamma quantum. The average angle of deviation of the gamma ray is also quite large and is in the radian measure a value of the order of 0.5. With the well-known expression of the total differential cross section and electron density, it is possible to determine the scattering length of gamma-ray 39 on an electron of media, which is 5-6 cm. From this, we can determine the attenuation of the coherent radiation flux of gamma-ray 48 from the place where the radiation occurred, before places from which radiation will occur in the space of Fig.7. If the concentration of electrons in the solid state medium of uranium hydride is equal to

N _e = 0.276 · 10 ²⁵ cm ^-3 ,

then for the full scattering cross section of gamma-ray 39 on the electrons of the medium

S _c = 0.6112051881 · 10 ^-25 cm ² .

there is a weakening of the gamma-ray flux 39 as a result of inhibitory processes during scattering by electrons of the medium

I ₁ = I _og exp (-N _e S _c 100) = 0.1033275656 · 10 ¹⁹ s ^-1 · cm ^-2 .

If the length of the entire string of uranium hydride is L: = 100 cm, then taking into account all the processes of amplification of the intensity of gamma radiation and its attenuation, the total radiation of the flux of coherent gamma rays 48 along the entire length of rod 7 after scattering due to the Compton effect on cold The electrons of the solid state medium of uranium hydride is represented in the form:

For a given gamma-ray energy 39

E _g = 0.16 · 10 ^-4 erg

the total flow intensity of the radiated energy from the end face of the rod 7 will be

W _g = I _L E _g · 10 ^-7 : = 0.65 · 10 ¹⁴ W / cm ² .

Such a flux intensity of gamma rays 39 corresponds to the intensity of gamma radiation near the explosion of a megaton nuclear bomb. In addition, incoherent and coherent neutron emission occurs from the end face of rod 7, the intensity of which is comparable to the flux intensity of gamma rays 39, but with a lower power density by an order of magnitude, and coherent X-ray radiation due to inhibitory processes, the flux intensity of which exceeds the gamma intensity by an order of magnitude quanta. In this case, the main energy of the rod released during the decay of the uranium nucleus remains at the explosion site and goes mainly to thermal processes. The considered physical effect of re-emission of the gamma-ray flux 39 of a nuclear explosion into coherent gamma-ray radiation 48 is possible provided that the speed of the neutron wave 47 for a given parameter of the neutron source 25 is ahead of all speeds that can destroy this neutron wave. Estimated calculations of thermal processes show that the spatially inhomogeneous distribution of the fission chain reaction of 46 uranium-235 nuclei (the wave front of nuclear fission reactions) moves at a speed of 298 m / s. In this case, the front of the evaporation wave 42 moves at a speed of 25 m / s and increases with time, because there is an increase in the flux density of the released energy as a result of the passage of a neutron wave. We get that the front of the evaporation wave cannot get ahead of the front of the heat wave due to the independence of this parameter from temperature. All these movements of the processes under consideration occur along the rod 3 in one direction, to the opposite end of the rod. As a result of the evaporation of uranium atoms, vapor from uranium atoms moves in the opposite direction, creating a pressure P ₁ = 8.6 J / cm ³ on the end surface of the rod, the action of which generates a sound wave in the rod, also moving to the opposite end. Evaluation calculations also show that the velocity of the neutron wave front is ahead of all other velocities except the speed of sound.

The pressure generating a sound wave (compression wave 43) is relatively small and, moreover, has a positive value, since it accelerates the process of neutron deceleration and increases the neutron multiplication coefficient as a result of the compression of uranium in the transmission region. Thus, practically nothing influences the motion of neutron wave 47 and, moving along the single crystal 3 with a known speed, it will initiate the processes of chain fission of nuclear reactions throughout the rod 7. Depending on the properties of the fissile and moderating materials and reflectors, the critical dimensions of the rod are selected such so that, for example, to increase the duration of the process of "nuclear combustion" of such a rod (nuclear Bikford cord) Fig.7. In this case, there is no need to increase the length of the rod, since it is necessary to remove the maximum flux of directed particles (neutrons and gamma) from the rod. In the case under consideration, each wave propagation by a distance of the length of neutron capture by uranium nuclei (l _au = 3 · 10 ^-2 cm) emits gamma and secondary neutrons with a flux value W ₁ = 4 · 10 ²⁵ s ^-1 · cm ^-2 . However, this does not mean that radiation will occur only in one direction. Part of the radiation due to the geometric factor of the medium, namely approximately 0.8.W ₁ , will be emitted from the side surface of the rod. The total radiation time will be equal to the time taken by thermal neutrons for the entire length of the string, i.e. t _rad = 10 ^-3 s or less. The generated gamma rays 39 in the solid state medium of uranium hydride begin to move in the same medium. The average energy transferred from the gamma-ray electron to the electron is comparable in order of magnitude with the energy of the gamma-ray quantum. For a given initial gamma-ray radiation flux equal to I = 2 · 10 ²⁴ s ^-1 · cm ^-2 , the output radiation, having passed the entire length of the rod from uranium hydride, will become equal to I ₁ = 1,5 · 10 ¹⁹ s ^-1 · cm ^-2 . However, if we take into account that the thermal neutron front will move along the entire length of the string, constantly generating coherent gamma-quanta with the same value of the flux in each place of the medium, the output coherent radiation of gamma-quanta will be: I _L = 4 · 10 ²⁵ s ^-1 cm ^-2 . The energy transferred from gamma rays to electrons, as a result of Compton scattering, on the one hand should again be reemitted into gamma rays with approximately the same energy (induced radiation) due to inhibitory processes, and on the other hand, to heat up a solid-state medium due to ionization drag processes electrons on the atoms of the medium. The ratio of energy losses for both cases showed that these processes are practically equivalent to each other. By virtue of this braking processes were examined reradiation relativistic electrons in the atoms of the medium and it was shown that the magnitude of the inverse bremsstrahlung flux on the order exceeds the attenuated gamma ray flux and is equal to I _t = 4,3 · October ²⁵ s ^-1 · cm ^{- 2} . The rest of the energy transferred to the electrons should go to the heating of the solid-state medium. This value of the specific energy contained in these electrons is relatively small in order to produce a strong heating of the entire volume of the rod in the considered explosion time (10 ^-3 s). This means that during this time the entire pulse of coherent gamma quanta will be emitted from the rod, and then the entire rod of the reactor 12 will evaporate.

An achievement of the present invention is that physical phenomena and processes are described in terms of kinetic equations of nuclear physics, quantum equations of thermal neutron scattering in crystals of the quantum theory of a solid body, wave equations of neutrons in crystals, quantum-wave optics for neutrons, kinetic equations and equations of heat conduction propagation of the fronts of nuclear reactions, heat waves and evaporation waves in crystals, the equations of propagation of x-ray radiation and gamma radiation crystals. Numerical calculations of these processes are made and for the main of them graphs are constructed confirming the possibility of real implementation of the proposed device. In the present invention, the most complicated scientific and technical problems are sequentially solved from generally accepted physical positions:

- the physical mechanism of nuclear pumping by neutrons of the active medium of a single crystal from a hydride of elements of the uranium group is proposed and considered;

- conditions for increasing the time of a nuclear explosion up to 10 ^-3 s are calculated for this device;

- modes of pumping by thermal neutrons for coherent excitation of nuclear fission reactions of heavy nuclei and reradiation of part of the fission energy into fast neutrons and into coherent gamma radiation in a single crystal are considered and determined;

- the formation conditions, time regimes and velocities of the neutron wave, heat wave, evaporation wave, compression and rarefaction waves in the single crystal during the initiation of nuclear fission reactions of heavy nuclei are determined, and the physics of the processes of their formation is shown;

- the critical dimensions of a single crystal from a hydride of the elements of the uranium group and the parameters of the precritical mode of operation of the device were determined;

- the starting parameters of the device are determined;

- the necessary dimensions of the device and the modes of its launch are determined;

- the threshold value of the output flux of directional coherent gamma-ray laser radiation is determined, equal to about 10 ²⁵ s ^-1 · cm ^-2 , corresponding to a neutron radiation flux equal to 10 ¹⁴ W / cm ² , which is sufficient to protect planet Earth from collision with space objects.

Claims (8)

1. A method for producing directed coherent gamma radiation, comprising pumping an active medium in the form of a laser rod, characterized in that the laser rod is made of a single crystal in the form of an elongated cylinder, in the volume of which the nuclei of uranium hydride isotopes and hydrogen atoms are uniformly placed, the crystal lattice single crystal contains crystalline planes parallel to each other and to the axis of the laser rod, which is both a moderator for fast neutrons and its former a throne wave, a pump source, and an active medium, while the laser rod is sequentially enclosed in a metal shell made of a material that absorbs thermal neutrons, bearing a steel case with connecting flanges at its ends, a metal plug is sealed and rigidly mounted on one of the ends of the case, and on the opposite end there is rigidly mounted a steel cup closed from one end with an axial chamber and a shutter consisting of adjacent symmetrical radial chambers, one of which is rigidly installed the first TNT charge with a detonator is inserted in the axial chamber of the glass and a metal plug made of a material capable of absorbing neutrons radially moving into the second radial chamber of the shutter is installed in series; the external source of fast neutrons is axially moving through the glass in the form of a monolithic cylinder and a piston, a rigidly fixed second TNT charge with a detonator, which is placed near the closed wall of the glass, creates a critical regime in the single crystal by initiating and a chain reaction of fission of heavy uranium nuclei by thermal neutrons at the moment of contact of the end surface of an external source of fast neutrons with the end surface of a single crystal, sequentially undermining the first and second TNT charges, as a result of which the tube is knocked out by a gas pressure into a free radial shutter chamber to which an external source is moved fast neutrons and the piston, which with an enhanced contact across the entire surface uniformly presses the end face of the neutron source to the single crystal, form a neutron nnuyu wave along the longitudinal axis of the single crystal and then exit from the conical caps coherent and directional gamma radiation. 2. The method of producing directed and coherent gamma radiation according to claim 1, characterized in that the neutron wave is amplified in the direction of the axis of the single crystal due to reflection from its outer surface and diffraction reflection by the crystal planes of the single crystal. 3. The method for producing directional coherent gamma radiation according to claim 1 or 2, characterized in that phase coherent waves of neutrons and gamma rays are generated. 4. The method for producing directed coherent gamma radiation according to claim 1, characterized in that the front of the heat wave in the rod is formed by the intensity of an external neutron source so that the speed of the heat wave does not exceed the speed of the neutron wave. 5. The method for producing directed coherent gamma radiation according to claim 1, characterized in that the evaporation wave front of the rod is formed by the intensity of an external neutron source so that the evaporation wave velocity does not exceed the neutron wave velocity. 6. A device for generating gamma radiation containing a source of pumping of the active medium and the active medium in the form of a laser rod from a solid substance, characterized in that the laser rod is made of a single crystal in the form of an elongated cylinder, in the volume of which the nuclei of the uranium hydride isotopes are uniformly placed and hydrogen atoms, the crystal lattice of a single crystal contains crystalline planes parallel to each other and to the axis of the laser rod, which is also a moderator for fast neutrons, forming a neutron wave generator, a pump source, and an active medium, while the laser rod is sequentially enclosed in a thin foil shell made of a material reflecting thermal neutrons, for example, lithium hydride, a titanium cylindrical shell, a metal shell made of a material reflecting thermal neutrons, a metal shell made of a material absorbing thermal neutrons, bearing a steel casing with connecting flanges at its ends, a conical shape is sealed and rigidly mounted on one of the ends of the casing a cap, and on the opposite end there was rigidly mounted a steel cup closed from one end with an axial chamber and a shutter consisting of adjacent symmetrical radial chambers, one of which had the first TNT charge with a detonator rigidly mounted, hermetically and sequentially installed in the axial chamber of the cup the possibility of radial movement into the second radial chamber of the shutter a monolithic metal tube made of a material absorbing neutrons, made with the possibility of axial movement through the glass An external source of fast neutrons in the form of a monolithic cylinder and a piston, a second TNT charge with a detonator, which is located near the closed wall of the glass, is rigidly fixed. 7. The device for generating gamma radiation according to claim 6, characterized in that the cork is enclosed in a steel cylindrical shirt. 8. The device for generating gamma radiation according to claim 7, characterized in that the external neutron source is enclosed in a metal jacket closed from one end of a material that absorbs thermal neutrons and is directed toward the plug with the open end.

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