DD140086A1 - IONISATIONSSTRAHLENDETEKTOR - Google Patents

Description

Field of application of the invention

The invention relates to devices for measuring characteristics of the ionizing radiation, in particular to detection of the ionizing radiation.

The invention can successfully for Individualdosimetrie the X-ray, gamma and neutron radiation in the _industry: be used in various physical experiments medicine, radiation biology as well.

Characteristic of the known technical solutions

Ionization beam detectors based on phosphors which are intended for thermoluminescence dosimetry (TLD) are already known. The mode of action of such detectors is based on the fact that the energy of the ionizing radiation which is stored in the illuminated workplace when trapping electrons and holes is converted into luminescence energy with the generation of heat. These detectors are small in size and lightweight and are operable over a wide range of doses (see, e.g., Schwarz K.K. et al., "Thermoluminescence Dosimetry", Riga, "Snanije'Y (" 1968).

Most of the detectors for gamma and X-ray measurements, for example ₀ based on CaSO ₄ , CaF ₂ , LiR, BeO, Li ₂ B ₄ O ₇ , MgF ₃₁ Mg ₂ SiO ₄ , SrS, SrSO ₄ , BaSO ₄ be built up, correspond more or less to theirs

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Sensitivity and demands on the duration of maintenance of dosimetric information. The sum of lights illuminated by such a detector characterizes the dose absorbed in the detector material. In the solution of most radiation-metrological tasks but the dose must be determined, not by the detector, but by a specific irradiated object, for example *. from a soft biological tissue, bone tissue, etc. is absorbed. For this, the detector must have a controlled dependence of the sensitivity of the energy of the X-ray or gamma radiation, ie the energetic dependence of its sensitivity must be similar to the energetic dependence of the mass coefficient of the radiation energy absorption by the irradiation object. For example, in determining the doses absorbed by a soft biological tissue, one must ensure tissue equivalence of the detector, namely, by approximating the effective atomic numbers of the detector and soft biological tissues. Currently, the TLD uses a very limited number of tissue equivalent detector fabrics because the ability to select tissue equivalent precursors and appropriate activators is also limited. Thus, of the substances mentioned, only the phosphors obtained on the basis of LiF, Li ₂ B ^ O ₁ - ,, BeO have the effective atomic numbers close to those of the tissue. These . However, phosphors are highly sensitive, and their most common use for LiF and B ^ O is that the dose dependence is nonlinear.

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With the aid of the detectors intended for the TLD, the average energy of the X-ray and gamma radiation (radiation quality) can be determined. This is accomplished by comparing the displays of two or more detectors whose effective atomic numbers differ significantly (see, e.g., Bushong S.C. et al., "Health Physo", 26, No. 4-1974, pp. 358-360).

An effective registration of thennoneutron fluxes by means of the mentioned detectors is carried out either with the aid of phosphors in which elements with a large capture cross section for thermoneutrons such as lithium or boron are contained (cf., for example, Franz M., Stolz, Wc "Festkörper- 'Dosimetry of ionizing radiation', Moscow, published by "Atomizdat", 1973), or by activating a phosphor element, e.g. B. Oa (see, for example, Watanabe 3. et al., Health Phys., 19, 1970, p.

The intrinsic sensitivity of all substances usable for the TLD to the fast neutrons is very low, and for the detection of fast neutrons either the proton radiation method is used (compare z, B, Sunta CM et al., Pros. Symp. On Neutron Monitoring for Radiation Protection, Purposes, Vienna, 1972, IAEA, Vienna, 1973, p. 57-62) or the reflection dose measurement method (see B. B. Korba A. et al., Health Phys. J8, 1970, pp. 581-584), but these methods are complicated and have a number of limitations and shortcomings.

Of interest is the method of neutron registration in 'neutron fields and mixed Ganma neutron fields.

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This method is based on the fact that the excitation with neutrons can lead to a change in the ratio of thermal illumination peaks (see, for example, Kudelin K.M. "Atomic Energy", 2, 4, 1972, p 331 - 333). Disadvantages of this method are the nonreproducibility of the results even with the same basic substance (LiP), the detection of only comparable gamma and neutron fluxes and the impossibility of a longer information storage. ''

To the. Unlike the detectors used for the.TLD, both organic and inorganic substances are used for the well-known scintillation detectors, with the help of which many tasks of regimented registration of the ionizing radiation of different types and energy levels can be solved (see, for example, Ramm WJ, "Scintillation Detector" in "Radiation Dosimetry" Eds: Attix FH, Roesch W. C, Tochilin E., vole ¹ II "New-York and London," Academic Press 1966, pp. 123-167.) Large Dimensions However, the use of scintillation detectors for individual and clinical dosimetry as well as for many experiments precludes the use of organic substances for the TLD because of the instability of their luminescence properties in the case of temperature effects.

The best dosimetric parameters are found in the ionization radiation detectors in which manganese-activated calcium fluoride CaFg: Mn is used as the phosphor (cf., for example, US Pat. No. 3,323,856, class 252-301.4, 1966) ).

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These detectors have a high sensitivity to X-ray and gamma radiation, a convenient read-out for thermoluminescence, a broad range of linear dependence of the thermoluminescence yield on the radiation dose and can keep the stored light sum long ·

The main deficiency of the on the basis of CaF _2: Mn constructed detectors lies in their unsuitability for reglamentiert en _φ detection of ionizing radiation of various types and power levels, and this is related to the following in connection. ¹

As with most inorganic substances, CaFo ^{1 is} characterized by a strong energetic dependence on its sensitivity. As a result, the values displayed by the detectors strongly depend on the spectrum of X-ray and gamma radiation at a constant value of the exposure dose of X-ray and gamma radiation are. Thus, the sensitivity of CaF ₂ : Mn to the radiation with an energy of 30 keV is higher by a factor than that of a radiation whose energy is 1.25 Me? is. This energetic dependence can be partially corrected by means of metal filters which absorb the low-energy range of the photon-beam spectrum. However, this correction method has significant disadvantages: increasing the size, weight and cost of the detector, shifting the lower limit of detectable radiant energy and the angular dependence of the sensitivity, The last defect can be achieved by using spherical filters.

be eliminated, with a further enlargement of the

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Dimensions, weight and cost of the detector must be accepted.

Like all phosphors which do not contain elements with large thermal neutron capture cross section, CaFp: Mn has low sensitivity to thermal neutrons.

Characteristic of CaFoUIn, as for all inorganic phosphors, is its low sensitivity to fast natron.

The CaF ₂ : Mn ~ detector also does not permit selective detection in mixed gamma and neutron fields.

The detector based on CaFp: Mn also gives no possibility to determine the quality of the X-ray and gamma radiation.

Object of the invention

The aim of the invention is to ensure reglamentierter 'registration of different types of radiation and the determination of the average energy of the X-ray and gamma radiation spectrum. ^!

Explanation of the essence of the invention

The invention is based on the object of developing an ionization radiation detector based on substances which has a controlled dependence of the detector sensitivity on the energy of the X-ray and gamma radiation.

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Provide radiation and enable effective registration of neutrons in neutron fields of sawiäin mixed gamma neutron emitters *

According to the invention the object is achieved in that in an ionization radiation detector with a phosphor according to the invention, a scintillator for the detected ionizing radiation is additionally used and the detector is designed as the Szintallator and the phosphor connecting'Baueinheit, wherein the thermoluminescence excitation spectrum of the phosphor the emission spectrum of the scintillator covers. '

To detect the X-ray and Gainmstrahlung a substance is suitably used as a scintillator, which has a reglamentierte dependence of the luminous efficacy of the energy of the X-ray and gamma radiation, and for the phosphor used a substance in which in the excitation with the X-ray or gamma radiation and with the Szintillatoreinission different tips of the thermal illumination result.

For the registration of neutron beams in neutron fields and in mixed gamma neutron fi elds, the scintillator may be used analogously to a substance which is characterized by an effective light yield on exposure to neutrons of the energetic area to be detected, the phosphor selected being a special peak of the thermal illumination upon excitation the scintillator radiation must result ·

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As a scintillator one can also use a tissue-equivalent substance when registering the X-ray and gamma radiation.

For the determination of the X-ray and gamma radiation dose as well as the mean spectrum energy of this radiation, it is expedient to use an air-equivalent substance as a scintillator.

The phosphor can be used with samarium, and terbium-activated strontium sulfide (SrS: SmTl).

The described embodiment of the ionization radiation detector according to the invention makes possible the regimented registration of various types of ionizing radiation.

Execution of the games

The invention will be explained in more detail in the following description of the specific embodiments and with reference to the attached drawing, in which the curves of the thermal illumination of the phosphor in the ionization radiation detector according to the invention are shown.

According to the invention, the ionization radiation detector is designed as a structural unit which contains a combination of a scintillator sensitive to the ionizing radiation to be detected and a phosphor whose thermoluminescence excitation spectrum coincides with the emission spectrum of the scintillator.

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The effectiveness of the registration of the types of ionizing radiation depends on the design features of the detector design according to the invention, especially on the type of scintillator and phosphor combination (fusion, sintering, mechanical mixing of finely dispersed components, optical contact between the scintillator and the phosphor, etc .). Decisive in the choice of the combination type is the chemical composition of the components and the possibility of their common heating in the Thermoausieuchtung. When using organic substances for the scintillator example, the scintillator and phosphor patterns are brought into contact, irradiated together and stored, while the reading process (heating and Thermolumineszenzabnahme) is subjected only to the phosphor.

For the detection of X-ray and gamma radiation serves as a scintillator imrlonisationsstrahlendetektor according to the invention, a substance with regulated dependence of the light yield of the energy of X-rays and gamma, while the selected phosphor with any energetic dependence of the thermoluminescence yield different peaks of the thermal illumination during its excitation has some of the scintillator emission by X-ray or gamma radiation. This additional requirement placed on the phosphor is due to the fact that the reglamentated detector response in case of a collection of the charge carriers at the same Binfangsniveaus be only one? effective energy transfer from the scintillator to the phosphor can be obtained »in fulfillment of these additional

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Requirement, the reglamentierte response is achieved regardless of the effectiveness of the energy transfer, with the reading takes place after different thermal illumination tips. A peak characterizes the sum of light stored by the absorption of the ionizing radiation by the phosphor itself (non-rectified response) and the other indicates the sum of light stored due to the scintillator radiation absorbed by the phosphor (controlled response).

The registration of the X-ray and gamma doses equivalent to the doses absorbed by the soft biological tissue is achieved by employing for the scintillator in a variant of the detector according to the invention a tissue-equivalent substance whose effective atomic number approximates the effective atomic number dos biological tissue (hereinafter referred to as "tissue-equivalent scintillator"). The resulting extensive possibilities to achieve the stated goal by combining the tissue-equivalent scintillator with a phosphor are characterized by a large choice of organic materials such

 Anthracene, naphthalene, stilbene for such a scintillator conditional '· ·

For the phosphor, samarium and terbium activated strontium sulfide SrS: Sm, Tb are used.

The determination of the X-ray and gamma radiation quality is carried out in another embodiment of the detector according to the invention by use for the scintillator of an air-equivalent substance, which thus has a

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extending in the air energy dependence of the Massenkoe ~ ffizienten the absorption of the X-ray and gamma radiation energy having · Such Ais guiding the z ™ ¹ patent pending detector allows to determine both the X and gamma radiation dose and the mittue spectrum energy of this radiation. The same organic base materials as in the tissue equivalent substances can serve as air equivalent substances. However, a corresponding correction is necessary for ensuring the equality of effective atomic numbers of the selected substance and the air.

The phosphor used in conjunction with such a scintillator should be subject to the same additional requirement that must be met in the case of controlled detection of X-ray and gamma radiation doses. In the mentioned embodiment, the phosphor SrS: Sm, Tb is used. , , ,

When registering the neutron radiation in neutron fields and in mixed Gammä Neutronenfeidern a substance is successfully used in the ionization radiation detector according to the invention as scintillator, which provides an effective light output upon exposure of neutrons of the detected energetic area, while the phosphor is a substance is used a special thermal illumination peak corresponding to the excitation by the scintillator emission results ·. The mentioned additional requirement for the phosphor also applies to the selective detection of neutrons in the mixed gamma neutron fields. '

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In order to register thermal neutrons, another embodiment of the ionization radiation detector uses a scintillant which has an effective luminous efficacy when exposed to thermal neutrons. For such a scintillator, it is possible to use substances which crosswise intersect the elements of large Wi-rk with respect to the thermoneutrons such as Li, B and the like. One of the most effective scintillators for thermoneutrons is zinc sulfide (ZnS: Ag ₁ B) activated with silver and an addition of boron.

In this embodiment variant of the detector, strontium sulfide activated as samarium by samarium and terbium is used.

For detection of fast neutrons, a scintillation agent is used in another variant of the ionization radiation detector, which is characterized by an effective light output when influenced by fast neutrons. As such scintillator hydrogen-containing substances, for. B. liquid and plastic scintillators, optionally polystyrene with paraterphenyl and POPOP ¹ V ^ be used.

The phosphor used here is SrS: Sm ₁ Tb.

The full potential of achieving this goal by combining the neutron scintillators with a phosphor is thus due to the presence of highly effective thermal neutron scintillators such as ZnS: Ag, B, as well as a wide choice of organic neutrons.

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see water material hai tig en raw materials for the preservation of scintillators for fast neutrons conditioned. As a general purpose phosphor, strontium sulfide (SrStSm, Tb) activated with samarium and terbium is used for the proposed detector.

The ion beam detector according to the invention operates as follows:

The ionization radiation detector according to the invention comprises a combination of a scintillating substance with regulated dependence of the light yield on the X-ray and gamma radiation energy and a phosphor with different thermal illumination peaks when excited by X-ray or gamma radiation and by the scintillator emission is irradiated with X-rays or gamma rays. These rays are absorbed by both the scintillator and the phosphor. The absorption of the X-ray and gamma radiation by the scintillator is accompanied by its illumination, whereby the dependence of the luminous efficacy of the scintillator on the X-ray and gamma radiation energy is determined by the energetic dependency of the mass coefficient of absorption. Thus, if the scintillator is tissue equivalent, its luminous efficacy characterizes the radiation dose equivalent to that absorbed by the soft biological tissue. The illumination of the scintillator excites the thermoluminescence of the phosphor and this occurs in a thermo-illumination tip. The absorption of X-ray and gamma radiation excites the thermoluminescence that comes to light in the other subject illumination tip.

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The ionization radiation detector according to the invention, which comprises a combination of the effective light scattering scintillator when exposed to neutrons of the energy region to be postulated and the phosphor having a separate theoimaging tip corresponding to the excitation by scintillator emission, will be mentioned. Neutrons irradiated in a neutron field or a mixed gamma neutron field. The operation of this detector is similar to that of the described detector.

An essential difference lies in the fact that the phosphors ζ, B. are practically insensitive to the fast neutrons and the thermoluminescence is consequently excited only by absorption of the light emission of the scintillator and is characterized mainly by a thermal illumination tip.

There is also a certain difference in the absorption of the radiation energy by the scintillator. In neutron irradiation, the interaction of the neutrons, the thermoneutrons, is primary with an element having a large cross section of action with respect to these neutrons, while fast neutrons primarily interact with the hydrogen of the scintillator. '

In neutron irradiation of the proposed detector in mixed gamma neutron fields, the doses of individual types of ionizing radiation are determined by means of the intensity-calibrated thermal illumination tips

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Hereinafter, concrete embodiments of the proposed ionization radiation detector will be described.

example 1

The ionization beam detector for registering the X-ray and Gaia radiation doses equivalent to the doses absorbed by the soft biological tissue contains, according to the invention, a tissue-equivalent scintillator obtained on the basis of anthracene and a phosphor directly connected thereto (or via an optical fiber) Samarium and terbium activated strontium sulfide (SrS: Sm, Tb) exists.

Anthracene can directly fulfill the puncture of the tissue-equivalent scintillating agent. Its effective atomic number, however, is slightly smaller than that of the soft biological tissue, and this leads to some non-equivalent in the low energy region of the X-ray and Gainmastrahlungsspektrums. To achieve complete equivalence, the well-known compensation method is used (see, for example, Arsayev MI et al., "Atomic Energy", J> 7, No. 4-1969, p. The material obtained as a result of this combination stß.llt represents an effective tissue-equivalent scintillator, in which the dependence of the light output from the energy similar to the energy dependence of the mass coefficient of the radiation energy absorption by the soft biological tissue is · The emission spectrum of the B _a sis of ftnthra - zen scintillator obtained has a maximum at 445 nm.

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The phosphor SrS: Sm, Tb, which acts as an accumulator of this light emission, has the property of being excited to undergo thermoluminescence both when exposed to X-ray and gamma radiation and when influenced by the emission of the selected scintillator.

As can be seen from the drawing, in which on the abscissa axis the temperature T in ⁰ G and on the ordinate axis the intensity I of the thermoluminescence are removed in relative units, that of the phosphor SrS: Sm, Tb only as a result of 'its own absorption of the X-ray or gamma radiation is mainly characterized by the lower temperature peak "a" of the thermal illumination curve 1. The analysis of the thermal illumination curve 1 showed that the part of the phosphor stored by inherent absorption of the ionizing radiation and in the high temperature peak "b" illuminated total amount of light (Sp) is constant and equal to 6% of the part of the total in the low temperature peak "a" illuminated total sum (S ₁ ). ,

In the X-ray or gamma irradiation of the detector, which consists of a combination of the selected scintillator and the phosphor SrS: Sm, Tb, the latter stores a sum of light which is illuminated according to the two comparable peaks of the thermal illumination curve 2, of which the low temperature peak "a "characterized by the self-absorption of the ionizing radiation by the phosphor light sum S ₁ characterized and the high-temperature peak mainly

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denotes the sum of light SO stored by the phosphor at the expense of the energy supplied to it by the tissue - equivalent scintillator ₀

As the analysis of the thermal illumination curve 1 shows, the following expression applies to the sum of lights Sp (thermal illumination curve 2):

^S 2 ⁼ . ^S 2 - ° ^{'06 S} 1 ⁽¹⁾

It has been experimentally proved that the sum of light S i, with the decrease of the X-ray and gamma-ray energy (E j), strongly increases as expected. Thus, at Ej = 80 keV, S ^ is about 30 times higher than at E ^ = MeV (assuming a constant dose of exposition).

Under the same conditions, however, Sp changes only insignificantly in a broad energy range E and follows the energetic dependence of the mass coefficient of radiation absorption by a soft biological tissue.

Example 2 .

According to the invention, the ionization radiation detector suitable for determining the average energy of the X-ray and gamma radiation spectrum contains an air-equivalent scintillator formed on the basis of stilbene and a phosphor connected directly to it (or via an optical fiber), namely samarium and terbium-activated strontium sulfide (SrSiSm, Tb). ,

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The stilbene-based air-equivalent scintillator was obtained similarly to the tissue-equivalent scintillator of the above example. Its emission spectrum has a maximum at 410mn.

The phosphor SrS: Sm, Tb, which acts as an accumulator of this light emission, has the property of being excited to undergo thermoluminescence upon exposure to X-ray and gamma radiation as well as being influenced by the emission of the selected scintillator.

In the X-ray or gamma radiation of the detector j, which consists of a combination of the selected air-equivalent si scintillator and the phosphor SrS: Sm, Tb, the latter stores, similar to Example 1, a sum of light corresponding to the two comparable peaks (thermal illumination curve 2) is illuminated, of which the low-temperature peak "a ^M , which is due to the self-absorption of the ionizing radiation by the phosphor stored sum of light S ^, characterized and the high-temperature peak mainly the light

sum Sp stored by the phosphor at the expense of the energy supplied by the scintillator. The sum of light So w: Example 1 described »

de. The sum of light So is expressed by the same expression of

Obviously, the average energy of the X-ray and Gainmastrahlungsspektrums can be easily determined from the ratio S ^ / S ^, since the sum of the light S ^ the mass coefficient (j4- / f ) enSrS: Sm, Tb of ^{the strall} lungsenergie-

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absorption by the phosphor SrS: Sm, Tb proportional

., and the light amount S ₂ of the Masaenkoeffizienten (^ Vj ⁷⁾ _{Θ η0} ^{of s "ratLlun} S ^sener S ^IEAB absorption through the air is proportional, while the dependence of the ratio Cr //) ensrs: sm _t Tb ^{of the}

enO

X-ray or gamma radiation can be determined from the known equations or from tables (cf., for example, Sinclair WK "Radiobiological Dosimetry", in "Radiation Dosimetry", Eds, Attix F.H., Roesch W. C, Tochi Lin E., vol. III, New York and London, "Academic Press", 1969, p. 626).

Example 3

The ionization beam detector according to the invention for registration of thermoneutron streams comprises a scintillator constituting ZnS: Ag, B activated by silver with a boron additive, and a phosphor consisting of samarium and terbium activated strontium sulfide SrS: Sm, Tb in which the scintillator and the phosphor are connected to each other directly (or via an optical fiber, or as a mechanical mixture of finely dispersed powders). In the latter EaIl the thermoluminescence of ZnSiAg., B is to be eliminated when reading the information.

The emission spectrum of the scintillator ZnS: Ag, B has a maximum at 4-50 nm.

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The phosphor SrS: Sm, Tb acts as an accumulator of this optical emission and has the property of being excited by the emission of the selected scintillator for thermoluminescence.

In the thermoneutron irradiation of the detector, which consists of a combination of the scintillator ZnS: Ag, B and the phosphor SrS: Sm, Tb stores the latter

ι

a sum of light that is illuminated according to a high-temperature peak (thermal illumination curve 3). The low temperature peak is missing in this case, since the intrinsic sensitivity of SrS: Sm, Tb is low compared to thermal neutrons, and the high temperature peak characterizes the light amount that is stored by the phosphor upon exposure to the supplied thereto from the scintillator power _o Thus, this peak characterizes the Thermoneutronenfluß ,

Upon irradiation of this detector with mixed gamma-neutron radiation (gamma radiation + thermal neutrons), the phosphor SrS: Sm, Tb stores a sum of light which in the graph is illuminated as two peaks (thermal illumination curve 2), of which the low temperature peak "a" is the light total Sa characterized which is saved due to the absorption of gamma radiation by the phosphor itself, while the high temperature peak mainly represents light sum Sg that is stored by the phosphor at the expense of the transferred to him by the scintillator energy. The sum of light SO is defined by the same expression of Example 1. However, this sum of light characterizes the

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Thermoneutron flux only in the presence of a weak, the neutron radiation accompanying gamma-base, since the scintillator ZnSrAg, B not only against Thermoneutronen. but is also sensitive to gamma radiation. _ .. ''

If the neutron radiation is accompanied by a strong gamma-ground and this case is therefore the condition ^ 1 ^ ^s ^ ^s P ®2 ^r i ^cn ^ t the sum Thermoneutronenfluß by the light ·

^b 2 - ^b 2 ^b 2 ^U;

s p denotes the sum of light which is stored by the phosphor SrSrSm, Tb on the basis of the emission due to the sensitivity of ZnSrAg, B against the gamma radiation of this scintillator 1 and illuminated in accordance with the high-temperature peak "b." The value of SO with respect to £ L may be due to irradiation of the gamma rays.

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detector, where So automatically includes the size of 0.06S ^. '- ·

Example 4

The ionization beam detector provided in accordance with the present invention, which is intended to register fast neutron fluxes, contains a combination of a plastic scintillator (polystyrene with paraterphenyl and POPOP) and a phosphor directly connected thereto (or via a light guide), samarium and terbium activated strontium sulfide (US Pat. SrSrSm, Tb).

The emission spectrum of the selected scintillator has

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a maximum in the range of 390 * * x 430 nm.

The phosphor SrS: Sm, Tb acting as the accumulator of the scintillator emission has the property of being excited by the light emission of the selected scintillator for thermoluminescence.

Upon irradiation of this fast neutron detector consisting of the combination, the selected scintillator and the phosphor SrSrSm, Tb, the phosphor stores a sum of light which is illuminated in the form of a high-temperature tip (thermal illumination curve 3). The low-temperature peak is absent in this case, since the intrinsic sensitivity of SrS: Sm, Tb to fast neutrons is low. In this case, the high-temperature peak characterizes the sum of light which is stored by the phosphor when the energy supplied by the scintillator is applied, thus it characterizes the fast neutron flux.

Upon irradiation of this detector with a mixed gamma-neutron radiation (gamma + fast neutrons) the flux of fast neutrons, as in Example 3 is "characterized by the light sum S ^, which is determined either by the expression (1) (if S _x , <^ S ^ is), or results from the expression (2) · (if S _-1 ^ Sp), since the scintillator is sensitive not only to fast neutrons but also to gamma radiation.

From the examples given it can be seen that with

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The tissue equivalence is achieved (with the phosphor used being SrSiSm, Tb not tissue equivalent) and the ability to determine the quality of the X-ray and gamma radiation (while determining the radiation quality with no single-use detector designed for thermoluminescence dosimetry), as well as neutrons in neutron fiders and mixed gamma neutron fiders (the phosphor SrS: Sm, Tb is virtually insensitive to neutrons). When using the detector according to the invention, the dosimetric information can also be "preserved" well, since most of the information stored in SrS: Sm, Tb contains the high-temperature peak of the thermal illumination.

The possibility of regimented registration of various. Types of ionizing radiation is given by the fact that in the inventively executed detector, the puncture of the radiation energy absorption, which is taken over by the scintillator, and the function of the storage of dosimetric information fulfilled by the phosphor are at least partially separated. In contrast to the prior art, for the thermoluminescent dosimetry _t certain detectors;? Earth this to the phosphor no requirements concerning the ieglamentierten absorption of ionizing radiation, or the effectiveness of Lichtsummenspeieherung under the influence of this radiation detected "

Claims (4)

May 11, 1979
53 628 16 205 728 Invention; sanspruch 1. Ionization beam detector with a phosphor, characterized in that the detector is a scintillator Lator for the detected ionizing radiation
additionally contains and as a scintillator
and the phosphor-connecting assembly is performed, wherein the thermoluminescence excitation spectrum
of the phosphor covers the emission spectrum of the scintillator 2, Ionisationsstrahlendetektor according to item 1, characterized in that for the detection of X-ray and
Gamma radiation as a scintillator uses a cloth
which has a controlled dependence of the luminous efficacy on the energy of the x-ray and gamma radiation, and for the phosphor a substance
which is used when excited by x-ray * or gamma radiation and scintillator emission
give different tips of the thermal illumination. 3 Ionisationsstrahlendetektor according to item 1, characterized in that for the registration of neutron beams in neutron fields and in mixed gamma neutron fields as a scintillator, a substance is used, which has an effective light output when exposed to neutrons of the detected energetic area, wherein the selected phosphor separate thermal illumination peak results, the - 25 - 11. 5 »1979 53 628 16 205 72 Excitement due to the scintillator emission. \. Ionization radiation detector according to item 2, characterized in that a fabric-equivalent substance is used as a scintillator. 5.. Ionization radiation detector according to item 2, characterized in that an air-equivalent Stpff serves as a scintillator and thereby the possibility is given to determine both the X-ray and gamma radiation dose and the average Spektrumenergie this radiation. 6 Ionization radiation detector according to item 2, 4 or 2, 5 or item 3, characterized in that samarium and terbium activated strontium sulfide (SrS: Sm, Tb) is used as phosphor » For this A page drawing -.