CN207472806U - Phot-neutron source and neutron check system - Google Patents

Abstract

The utility model discloses a kind of phot-neutron sources and neutron to check system.Phot-neutron source includes：Electronic acceleration tube, for accelerated electron beam stream；X ray converts target, and X ray conversion target generates X ray described in the electron beam bombardment accelerated through the electronic acceleration tube；Photoneutron target, the X ray enter the photoneutron target and generate photoneutron；Case is modulated with neutron, is covered at outside the photoneutron target, the neutron modulation case includes the neutrons collimation mouth for photoneutron output.The utility model can directly export required neutron streaming from the neutrons collimation mouth of phot-neutron source.

Description

Phot-neutron source and neutron check system

Technical field

The utility model is related to radiation monitoring technical field, more particularly to a kind of phot-neutron source and neutron check system.

Background technology

Neutron launches different characteristic energy photonics when reacting from different elements.Member based on special object Cellulose content feature and neutron and nuclear reaction mechanism, by detecting the feature gamma spectrum of detected material, determine the member of substance The proportionate relationship of element composition and each element, it is that explosive, drugs either general organic matter, accuracy are higher to be distinguished with this. Element composition such as explosive is usually C, H, N, O, and the content of N and O is higher, and the content of H and C are seldom；In many drugs Preparation process in, need the participation of chlorine-bearing compound, therefore, poison can be detected by the proportionate relationship for analyzing the elements such as H, N, Cl Product/noxious material easily processed.

Strong based on neutron penetration power, the advantages that can carrying out elemental analysis, in field of safety check, can use neutron to large size Article in container, oversize vehicle carries out Object Classification, reflects to material-specifics such as drugs that may be present or explosives Not.

The generation of neutron and transport be by neutron check article when entire physical process in the first step.In field of safety check Common neutron source has isotope neutron source and accelerator for neutron production, but both neutron sources are in neutron yield, service life etc. Aspect has respective insufficient and drawback, and quick check for bulky items is not optimal selection.

Utility model content

The purpose of this utility model is to provide a kind of phot-neutron sources and neutron to check system, can directly export required Neutron streaming.

The utility model first aspect provides a kind of phot-neutron source, including：Electronic acceleration tube, for accelerated electron beam stream；X Ray converts target, and X ray conversion target generates X ray described in the electron beam bombardment accelerated through the electronic acceleration tube；Photoneutron Target, the X ray enter the photoneutron target and generate photoneutron；With, neutron modulation case, cover at outside the photoneutron target Portion, the neutron modulation case include the neutrons collimation mouth for photoneutron output.

Further, the neutron modulation case covers at the electronic acceleration tube, X ray conversion target and the light Outside neutron-producing target.

Further, the X ray converts target part or is entirely located in the photoneutron target.

Further, the photoneutron target includes heavy water target or beryllium target.

Further, the photoneutron target is heavy water target, and the heavy water target is set to described including sealing shell and closing Heavy water in sealing shell, the sealing shell include concave portion, and the X ray converts target part or is entirely located in the female In portion.

Further, the heavy water target is cylindrical target, the electron beam of the axis of the cylindrical target along the electronic acceleration tube Stream goes out Shu Fangxiang settings.

Further, the electronic acceleration tube, X ray conversion target and photoneutron target coaxial arrangement.

Further, the electronic acceleration tube is located at the top of X ray conversion target and the photoneutron target, the X Ray converts target part or is entirely located in the top of the photoneutron target.

Further, the neutron modulation case includes the shielded layer for shielding X ray, and the shielded layer is set to institute State the outside of photoneutron target.

Further, the shielded layer is set to the electronic acceleration tube, X ray conversion target and the photoneutron target Outside.

Further, the shielded layer includes shielding X ray and shielding the first shield of neutron and for shielding X The secondary shielding body of ray and transmission neutron.

Further, first shield includes lead screen body, and the secondary shielding body includes bismuth shield.

Further, first shield and the secondary shielding body are formed using shielding material of the same race, and described second The thickness of shield is less than the thickness of first shield.

Further, first shield and the secondary shielding body are lead screen body.

Further, the shielded layer includes bismuth shielded layer or bismuth alloy shielded layer.

Further, first shield includes being located at the shielding case outside the photoneutron recurring structure, described Shielding case has neutron delivery outlet, and the secondary shielding body is set in the neutron delivery outlet and closes the neutron output Mouthful.

Further, the neutron delivery outlet is located at the side for going out Shu Fangxiang of the electronic beam current.

Further, the neutron modulation case, which further includes, is set on the outside of the shielded layer with the neutron of slowing down photoneutron It slowing down layer and/or is set on the outside of the shielded layer to absorb the neutron absorbing layer of photoneutron.

Further, the neutron modulation case includes the moderation of neutrons layer and the neutron absorbing layer, the neutron Absorbed layer is set to the outside of the moderation of neutrons layer.

Further, the moderation of neutrons layer includes graphite layer or heavy water absorbed layer；And/or the neutron-absorbing Layer includes boron carbide absorbed layer, paraffin absorbed layer, boracic paraffin absorbed layer or Boron-containing-PE absorbed layer.

Further, the shielded layer includes shielding X ray and shielding the first shield of neutron and for shielding X The secondary shielding body of ray and transmission neutron；The moderation of neutrons layer includes the first slowing down portion and thickness is less than first slowing down The second slowing down portion in portion, the first slowing down portion are set on the outside of first shield, and the second slowing down portion is set to institute It states on the outside of the first shield.

Further, the shielded layer includes shielding X ray and shielding the first shield of neutron and for shielding X The secondary shielding body of ray and transmission neutron；The neutron absorbing layer has the neutron hair for being set to the external side of the secondary shielding Penetrate window.

Further, the neutron modulation case further includes the neutron howitzer for controlling NEUTRON EMISSION shape, described Neutron howitzer is located in the NEUTRON EMISSION window, and the neutron howitzer includes the neutrons collimation mouth.

Further, the phot-neutron source further includes waveguide, and the waveguide includes connecting with the electronic acceleration tube straight Pipeline section and the boot segment being connect with the straight pipe, at least part of the boot segment have angle with the straight pipe.

Further, the waveguide is arranged in the neutron modulation case.

The utility model second aspect provides a kind of neutron and checks system, including any one of the utility model first aspect The phot-neutron source.

Further, the neutron checks that system checks system for vehicular.

Further, the electronic beam current of the electronic acceleration tube goes out Shu Fangxiang perpendicular to ground.

System is checked based on phot-neutron source provided by the utility model and neutron, phot-neutron source includes electronic acceleration tube, X is penetrated Line conversion target, photoneutron target and neutron modulation case, can directly export required neutron from the neutrons collimation mouth of phot-neutron source Line.Further, the phot-neutron source is compact-sized, and installation and debugging are simple and convenient.Neutron checks that system includes the phot-neutron source, With phot-neutron source with all advantages.

By referring to the drawings to the detailed description of the exemplary embodiment of the utility model, the utility model it is other Feature and its advantage will become apparent.

Description of the drawings

Attached drawing described herein is used to provide a further understanding of the present invention, and forms the part of the application, The illustrative embodiments and their description of the utility model are not formed for explaining the utility model to the improper of the utility model It limits.In the accompanying drawings：

Fig. 1 is the structure diagram of the phot-neutron source of the utility model embodiment.

Specific embodiment

The following is a combination of the drawings in the embodiments of the present utility model, and the technical scheme in the embodiment of the utility model is carried out It clearly and completely describes, it is clear that the described embodiments are only a part of the embodiments of the utility model rather than whole Embodiment.It is illustrative to the description only actually of at least one exemplary embodiment below, is never used as to this practicality Novel and its application or any restrictions used.Based on the embodiment in the utility model, those of ordinary skill in the art are not having All other embodiments obtained under the premise of creative work are made, shall fall within the protection scope of the present invention.

Unless specifically stated otherwise, the component and positioned opposite, the digital table of step otherwise illustrated in these embodiments Up to the unlimited the scope of the utility model processed of formula and numerical value.Simultaneously, it should be appreciated that for ease of description, each shown in attached drawing The size of a part is not to be drawn according to practical proportionate relationship.For skill known to person of ordinary skill in the relevant Art, method and apparatus may be not discussed in detail, but in the appropriate case, and the technology, method and apparatus should be considered as awarding Weigh part of specification.In shown here and discussion all examples, any occurrence should be construed as merely example Property, not as limitation.Therefore, the other examples of exemplary embodiment can have different values.It should be noted that：It is similar Label and letter similar terms are represented in following attached drawing, therefore, once be defined in a certain Xiang Yi attached drawing, then with In attached drawing afterwards do not need to that it is further discussed.

In the description of the present invention, it is to be appreciated that limiting zero using the words such as " first ", " second " Part, it is only for convenient for being distinguished to corresponding parts, such as without Stated otherwise, above-mentioned word there is no particular meaning, Therefore it is not intended that limitation to scope of protection of the utility model.

In the description of the present invention, it is to be appreciated that the noun of locality such as " forward and backward, upper and lower, left and right ", " laterally, Vertically, vertically, it is horizontal " and " pushing up, bottom " etc. indicated by orientation or position relationship be normally based on orientation or position shown in the drawings Relationship is put, be for only for ease of description the utility model and simplifies description, in the case where not making to illustrate on the contrary, these nouns of locality It does not indicate that and implies signified device or element must have specific orientation or with specific azimuth configuration and operation, because This is it is not intended that limitation to scope of protection of the utility model；The noun of locality " inside and outside " refers to the wheel relative to each component in itself Wide is inside and outside.

Fig. 1 is the structure diagram of the phot-neutron source of the utility model embodiment.As shown in Figure 1, in the light of the embodiment Component mainly includes electronic acceleration tube 2, X ray conversion target 3, photoneutron target 4 and neutron modulation case.Electronic acceleration tube 2 is used for Accelerated electron beam stream.The electron beam bombardment X ray conversion target 3 accelerated through electronic acceleration tube 2 generates X ray.X ray enters light Neutron-producing target 4 simultaneously generates photoneutron.Neutron modulation case is covered at outside photoneutron target 4, and neutron modulation case is included in light The neutrons collimation mouth of son output.

Electronic acceleration tube 2, X ray conversion target 3, photoneutron target 4 and neutron are modulated case together as one by the phot-neutron source, Required neutron streaming can be directly exported from the neutrons collimation mouth of phot-neutron source, compact-sized, installation and debugging are simple and convenient.

In addition, phot-neutron source is as a kind of novel neutron source, relative to other kinds of neutron source, such as in isotope Component and accelerator for neutron production, have many advantages, such as, can meet the requirement quickly checked bulky items.Wherein：

Field is checked for special object, contraband, checks that efficiency is an important factor, for this purpose, for neutron inspection System, it is necessary to assure check channel in neutron have very high fluence rate, therefore use neutron source need it is higher in Sub- yield.The yield of photoneutron is high, relative to accelerator for neutron production and isotope neutron source, can improve detection speed.

The long lifespan of phot-neutron source, and common isotope neutron source such as 252Cf, half-life period is 2.65, in common The service life highest of electronic generator is also only thousands of hours.

Phot-neutron source is electric radiographic source, and radiogical safety is good, and radiation is not generated in transport, installation and debugging process.

Relative to accelerator for neutron production, the complexity of phot-neutron source is small, at low cost, easy to maintain.

The phot-neutron source of the utility model embodiment can be applicable to safety inspection field, to van container, oversize vehicle The material-specifics such as interior drugs that may be present or explosive are identified.

The utility model embodiment is described in detail below in conjunction with Fig. 1.

As shown in Figure 1, the phot-neutron source of the present embodiment includes waveguide 1, electronic acceleration tube 2, X ray conversion target 3, photoneutron Target 4 and neutron modulation case.Neutron modulation case includes shielded layer, moderation of neutrons layer 6, neutron absorbing layer 7 and neutron howitzer 8。

The light that the phot-neutron source is generated after being acted on using the X ray that pulsed electron linear accelerator generates with photoneutron target 4 Neutron is as neutron source.It generates photoneutron and includes X ray generation and photoneutron two processes of generation：Add in electronic acceleration tube 2 Speed electronically forms low Z materials of the bombardment as X ray conversion target 3 after high-power electron beam, and with low Z materials bremsstrahlung occurs for electronics Effect generates sigmatron.Sigmatron enters after optical neutron converting target 4 occurs photoneutron reaction with atomic nucleus, generates Photoneutron.

X ray conversion target 3 can for example be made of gold and tungsten.

As shown in Figure 1, in this example, neutron modulation case covers at electronic acceleration tube 2, X ray conversion target 3 and photoneutron Outside target 4.The setting integrates neutron modulation case, electronic acceleration tube 2, X ray conversion target 3 and photoneutron target 4, pacifies Adjustment examination is convenient, and radiation is low, safe.

As shown in Figure 1, the present embodiment is preferably, X ray conversion target 3 is entirely located in photoneutron target 4.Show in other diagrams Embodiment in, X ray conversion target 3 can partly be located at photoneutron target 4 in, can also have a certain distance with photoneutron target 4.

Wherein, photoneutron target 4 can be heavy water target, or beryllium target.Since photoneutron reaction is there are energy threshold, i.e., When only the energy of photon is more than combination energy of the neutron in atomic nucleus, photoneutron reaction is possible to occur, therefore must selection Appropriate photoneutron transition material forms photoneutron target 4, ensures that its threshold of reaction is less than X-ray energy.The material usually chosen It is deuterium and beryllium, the photon threshold of reaction is respectively 2.223MeV and 1.67MeV.In the present embodiment, photoneutron target 4 is heavy water target.

As shown in Figure 1, heavy water target includes sealing shell and closes the heavy water being set in sealing shell.The top of sealing shell Portion includes concave portion, and X ray conversion target 3 is located in concave portion.Sealing shell for example can be aluminum shell.In the present embodiment, X is penetrated Line conversion target 3 is stretched into heavy water target, and X ray is resulted from the encirclement of heavy water during electronic target.X ray generates same When, energy can generate neutron higher than the X ray of photoneutron reaction threshold value with the deuterium alpha reaction in heavy water, and X ray is fully utilized.

In embodiment (not shown), X ray conversion target 3 can also partly be located in concave portion.

In the present embodiment, heavy water target is the cylindrical target that goes out Shu Fangxiang setting of the axis along electronic acceleration tube.Electronic acceleration tube 2nd, X ray conversion target 3 and photoneutron target 4 are coaxially disposed.

As shown in Figure 1, electronic acceleration tube 2 is located at the top of X ray conversion target 3 and photoneutron target 4, X ray conversion target 3 Divide or be entirely located in the top of photoneutron target 4.

The shielded layer of neutron modulation case is used to shield X ray.Shielded layer is set to outside photoneutron target 4.The present embodiment In, shielded layer is set to outside electronic acceleration tube 2, X ray conversion target 3 and photoneutron target 4.

As shown in Figure 1, shielded layer includes shielding X ray and shielding the first shield 5 of neutron and penetrate for shielding X The secondary shielding body 9 of line and transmission neutron.

Preferably, the first shield 5 includes lead screen body；Secondary shielding body 9 includes bismuth shield.

In another preferred embodiment, the first shield 5 and secondary shielding body 9 can be with using shielding materials of the same race Material, but use different thickness.For example, the first shield 5 and secondary shielding body 9 can be lead screen body, wherein the second screen Thickness ratio the first shield 5 for covering body 9 is thin.At this point, the thickness of the first shield 5 is larger, therefore X ray and majority can be shielded Neutron, the thickness of secondary shielding body 9 is relatively small, therefore, can shield most of X ray and a small number of neutrons, and most neutrons It can be exported by secondary shielding body 9.

In other embodiments, the first shield 5 can include bismuth shield or bismuth alloy shield；Secondary shielding body 9 It can include lead screen body or bismuth alloy shield etc..The addition of neutron-sensitive nucleic is watched out for when using bismuth alloy.

Wherein, the first shield 5 includes being located at the shielding case outside photoneutron recurring structure, and shielding case is defeated with neutron Outlet, secondary shielding body 9 are set to neutron equipped at outlet port and are closed neutron delivery outlet.

Preferably, neutron delivery outlet is located at the side for going out Shu Fangxiang of electronic beam current.As shown in Figure 1, in the present embodiment, electricity The electronic beam current of sub- accelerating tube 2 goes out downwards beam, coaxial with shielded layer, and neutron delivery outlet is set on the side of shielded layer.It should Setting so that phot-neutron source may be arranged to electronic beam current go out Shu Fangxiang towards ground, reduce at the top and bottom of phot-neutron source Protection requirements.

Preferably, secondary shielding body 9 is strip shape body setting up and down.The setting is corresponding with the shape of photon collimation mouth, fits In sending out fladellum.

Phot-neutron source can generate X ray during generating neutron, which can cause to do to the detection of Characteristic γ ray It disturbs.The phot-neutron source of the present embodiment carries out X ray and neutron using lead screen body and bismuth shield in the surrounding of photoneutron target 4 Shielding.Lead screen body is common X-ray shield body, but also has certain shielding action to neutron；Bismuth shield can shield X ray is covered, and does not have shielding action to neutron.So in the part of neutron delivery outlet using bismuth shield, other parts use Lead screen body, it is therefore an objective to realize that neutron is only emitted from forward direction collimating slit, other directions do not have X ray leakage and rare neutron to let out Dew.

In other unshowned embodiments, shielded layer can also be single shield, such as single bismuth shield, Bismuth alloy shield etc..

The moderation of neutrons layer 6 of neutron modulation case is set on the outside of shielded layer with slowing down photoneutron.Neutron in the present embodiment Slowing down layer 6 is graphite layer.

In other embodiments (not shown), moderation of neutrons layer can also be made of other materials.Such as or heavy water Slowing down layer or can be different slowing material layers combination.In deuterium oxide moderated layer, heavy water is placed in sealing shell.

As shown in Figure 1, moderation of neutrons layer 6 includes the first slowing down portion and thickness is less than the second slowing down portion in the first slowing down portion, First slowing down portion is set to 5 outside of the first shield, and the second slowing down portion is set to 5 outside of the first shield.

Neutron absorbing layer 7 is set on the outside of shielded layer to absorb photoneutron.In the present embodiment, neutron absorbing layer 7 is set to 6 outside of moderation of neutrons layer；Neutron absorbing layer 7 includes boron carbide absorbed layer.As shown in Figure 1, neutron absorbing layer 7, which has, is set to the The NEUTRON EMISSION window in two shields, 9 outside.

In other embodiments (not shown), neutron absorbing layer can also be made of other materials.For example, it is also possible to it is stone Wax absorbed layer, boracic paraffin absorbed layer, Boron-containing-PE absorbed layer or can be different layers of absorbent material combination.

X ray is substantially completely absorbed, but neutron is only partly absorbed after the shielding of lead screen body.So it also needs Slowing down and absorption are carried out to the neutron for passing through lead screen body.Slowing down will also be carried out for the neutron for passing through bismuth shield so that The neutron projected from collimating slit is largely thermal neutron.Slowing down, neutron and graphite are carried out to neutron using graphite in the present embodiment In C atoms collide, off-energy achievees the purpose that slowing down.Slowing down is carried out to neutron using boron carbide in the present embodiment, Wherein, B and thermal-neutron reaction section are larger, and the thermal neutron after graphite will react with the B in boron carbide, most at last It is absorbed by outermost boron carbide.

The neutron howitzer 8 of neutron modulation case is used to control NEUTRON EMISSION shape.Neutron howitzer 8 is located at NEUTRON EMISSION In window.Neutron howitzer 8 includes neutrons collimation mouth.As shown in Figure 1, in the present embodiment, neutrons collimation mouth is strip slot, right The shape for the neutron beam answered is fladellum.

In other embodiments (not shown), neutrons collimation mouth can be the other shapes such as round, rectangular, corresponding neutron Beam can be pencil beam etc..

The neutron that the phot-neutron source of the present embodiment is launched is largely thermal neutron.Compared to fast neutron, thermal neutron and spy Foreign matter element reaction section bigger.

As shown in Figure 1, waveguide 1 is arranged in neutron modulation case.Waveguide 1 includes the straight tube being connect with electronic acceleration tube 2 Section and the boot segment being connect with straight pipe, at least part and the straight pipe of boot segment have angle.The setting causes ray to pass through Crossing boot segment could be emitted later, i.e., turned to relative to straight pipe, reduce Environmental dose rate.

The utility model embodiment also provides a kind of neutron and checks system, including aforementioned phot-neutron source.The present embodiment Neutron checks system, has all advantages of aforementioned phot-neutron source, is not repeated to describe herein.

Preferably, neutron checks that system checks system for vehicular.It can be by operational window in vehicular inspection system Component is integrated on same vehicle chassis.Certainly, which can also apply in the operational windows such as combined type, fixed with setting In the standby neutron detection device with certain safe distance.

Preferably, the electronic beam current of electronic acceleration tube 2 goes out Shu Fangxiang perpendicular to ground.After electronic acceleration tube 2 End face is difficult to be shielded as 2 surrounding of electronic acceleration tube, and larger dose of radiation can be generated on the backward direction of electron beam. Electronic acceleration tube 2 is vertically arranged in the present embodiment, electronic beam current accelerates downward, and rear end is placed upwards, then only in increase Empty dose of radiation, in the case where no personnel carry out working at height, without expanding radiation protection area or increasing screening arrangement.Phase For state of the art setting, the dose of radiation that can be avoided result in horizontal direction increases, and leads to radiation protection region Increase or screening arrangement thicken.

Certainly, in other embodiments (not shown), the direction of electronic acceleration tube 2 can also as desired, towards in removing Direction other than beamlet stream.

From the above description, it can be seen that the utility model above example has at least one following technique effect：

Phot-neutron source has the characteristics that neutron yield height, long lifespan, radiogical safety is good, complexity is small.In can be applied to The material-specifics such as drugs or explosive that may be present in van container, oversize vehicle are differentiated in sub- detecting system.

Compared to other kinds of neutron source, detection speed and examination efficiency can be improved, in transport, installation and debugging process Emissivity is not generated, and easy to maintain.

The phot-neutron source can be applied in all kinds of neutron detection devices.It can not only be applied to combined type, fixed etc. Operational window has with equipment in the neutron detection device of certain safe distance, can also apply more demanding to radiogical safety Vehicular neutron inspection system on.Operational window is integrated in same vehicle chassis with neutron source in vehicular neutron inspection system On, when neutron checks system work, it can still ensure the radiation safety of staff in operational window.

All components of the phot-neutron source are integrated in one, and directly send out thermal neutron, and are collimated into required neutron beam, such as fan The pencil of forms, pencil beam etc., compact-sized, installation and debugging are simple and convenient.

Finally it should be noted that：Above example is only to illustrate the technical solution of the utility model rather than it is limited System；Although the utility model is described in detail with reference to preferred embodiment, those of ordinary skill in the art should Understand：It can still modify to specific embodiment of the present utility model or some technical characteristics are equally replaced It changes；Without departing from the spirit of technical solutions of the utility model, should all cover in the claimed technical solution of the utility model In range.

Claims (28)

1. a kind of phot-neutron source, which is characterized in that including：

Electronic acceleration tube (2), for accelerated electron beam stream；

X ray conversion target (3), X ray conversion target (3) produces described in the electron beam bombardment accelerated through the electronic acceleration tube (2) Raw X ray；

Photoneutron target (4), the X ray enter the photoneutron target (4) and generate photoneutron；With,

Neutron modulates case, covers at photoneutron target (4) outside, and the neutron modulation case is included for the photoneutron The neutrons collimation mouth of output.

2. phot-neutron source according to claim 1, which is characterized in that the neutron modulation case covers at the electronics and adds Speed pipe (2), X ray conversion target (3) and the photoneutron target (4) are external.

3. phot-neutron source according to claim 1, which is characterized in that the X ray conversion target (3) is positioned partially or entirely in In the photoneutron target (4).

4. phot-neutron source according to claim 1, which is characterized in that the photoneutron target (4) includes heavy water target or beryllium target.

5. phot-neutron source according to claim 1, which is characterized in that the photoneutron target (4) be heavy water target, the heavy water Target includes sealing shell and closes the heavy water being set in the sealing shell, and the sealing shell includes concave portion, and the X is penetrated Line conversion target (3) is positioned partially or entirely in the female portion.

6. phot-neutron source according to claim 5, which is characterized in that the heavy water target is cylindrical target, the cylindrical target Axis goes out Shu Fangxiang settings along the electronic beam current of the electronic acceleration tube (2).

7. phot-neutron source according to claim 1, which is characterized in that the electronic acceleration tube (2), X ray conversion Target (3) and the photoneutron target (4) coaxial arrangement.

8. phot-neutron source according to claim 1, which is characterized in that the electronic acceleration tube (2) turns positioned at the X ray Change the top of target (3) and the photoneutron target (4), the X ray conversion target (3) is positioned partially or entirely in the photoneutron target (4) in top.

9. phot-neutron source according to any one of claim 1 to 8, which is characterized in that the neutron modulation case includes For shielding the shielded layer of X ray, the shielded layer is set to the outside of the photoneutron target (4).

10. phot-neutron source according to claim 9, which is characterized in that the shielded layer is set to the electronic acceleration tube (2), the outside of the X ray conversion target (3) and the photoneutron target (4).

11. phot-neutron source according to claim 9, which is characterized in that the shielded layer includes shielding X ray and shielding Cover the first shield (5) of neutron and the secondary shielding body (9) for shielding X ray and transmission neutron.

12. phot-neutron source according to claim 11, which is characterized in that

First shield (5) includes lead screen body, and the secondary shielding body (9) includes bismuth shield.

13. phot-neutron source according to claim 11, which is characterized in that first shield and the secondary shielding body It is formed using shielding material of the same race, the thickness of the secondary shielding body is less than the thickness of first shield.

14. phot-neutron source according to claim 13, which is characterized in that first shield (5) and second screen It is lead screen body to cover body (9).

15. phot-neutron source according to claim 9, which is characterized in that the shielded layer includes bismuth shielded layer or bismuth alloy Shielded layer.

16. phot-neutron source according to claim 11, which is characterized in that first shield (5) is including being located at The shielding case outside photoneutron recurring structure is stated, the shielding case has neutron delivery outlet, and the secondary shielding body (9) is set to The neutron delivery outlet is interior and closes the neutron delivery outlet.

17. phot-neutron source according to claim 16, which is characterized in that the neutron delivery outlet is located at the electronic beam current The side for going out Shu Fangxiang.

18. phot-neutron source according to claim 9, which is characterized in that the neutron modulation case, which further includes, is set to institute Shielded layer outside is stated with the moderation of neutrons layer (6) of slowing down photoneutron and/or is set on the outside of the shielded layer to absorb photoneutron Neutron absorbing layer (7).

19. phot-neutron source according to claim 18, which is characterized in that it is slow that the neutron modulation case includes the neutron Change layer (6) and the neutron absorbing layer (7), the neutron absorbing layer (7) are set to the outside of the moderation of neutrons layer (6).

20. phot-neutron source according to claim 18, which is characterized in that the moderation of neutrons layer (6) is including graphite Layer or deuterium oxide moderated layer；And/or the neutron absorbing layer (7) is inhaled including boron carbide absorbed layer, paraffin absorbed layer, boracic paraffin Receive layer or Boron-containing-PE absorbed layer.

21. phot-neutron source according to claim 18, which is characterized in that the shielded layer includes shielding X ray simultaneously Shield the first shield (5) of neutron and the secondary shielding body (9) for shielding X ray and transmission neutron；The moderation of neutrons Layer (6) is less than the second slowing down portion in the first slowing down portion including the first slowing down portion and thickness, and the first slowing down portion is set to On the outside of first shield (5), the second slowing down portion is set on the outside of first shield (5).

22. phot-neutron source according to claim 18, which is characterized in that the shielded layer includes shielding X ray simultaneously Shield the first shield (5) of neutron and the secondary shielding body (9) for shielding X ray and transmission neutron；The neutron-absorbing Layer (7) has the NEUTRON EMISSION window being set on the outside of the secondary shielding body (9).

23. phot-neutron source according to claim 22, which is characterized in that the neutron modulation case further includes to control The neutron howitzer (8) of NEUTRON EMISSION shape, the neutron howitzer (8) is in the NEUTRON EMISSION window, the neutron Collimator (8) includes the neutrons collimation mouth.

24. phot-neutron source according to any one of claim 1 to 8, which is characterized in that the phot-neutron source further includes wave It leads (1), the waveguide (1) includes the straight pipe being connect with the electronic acceleration tube (2) and the guiding being connect with the straight pipe Section, at least part of the boot segment have angle with the straight pipe.

25. phot-neutron source according to claim 24, which is characterized in that the waveguide (1) is arranged in the neutron modulation In case.

26. a kind of neutron checks system, including phot-neutron source, which is characterized in that the phot-neutron source be according to claim 1 to Phot-neutron source described in any one of 25.

27. neutron according to claim 26 checks system, which is characterized in that the neutron checks that system is examined for vehicular Look into system.

28. neutron according to claim 26 checks system, which is characterized in that the electron beam of the electronic acceleration tube (2) Stream goes out Shu Fangxiang perpendicular to ground.