CN219271975U - Neutron target for boron neutron capture tumor treatment - Google Patents

Abstract

The utility model provides a neutron target for boron neutron capture tumor treatment, which is arranged between a proton beam outflow opening and a tumor patient, wherein the neutron target is provided with a semi-tire-shaped curved surface structure capable of rotating around a central shaft, and extends between an inner annular edge and an outer annular edge, and a concave surface is formed towards the proton beam outflow opening and a convex surface is formed towards the tumor patient; the proton beam is always aligned to the concave surface of the neutron target, and along with the rotation of the neutron target around the central axis, the irradiation position of the proton beam on the concave surface is continuously changed. According to the neutron target provided by the utility model, the neutron beam in the outgoing is more concentrated through the design of the semi-tire-shaped curved surface structure, the neutron number of 0-45 degrees is 2.14 times of that of the planar target in the same condition, the neutron number of more than 90 degrees is only 0.38 times of that of the planar target in the same condition, and the curved surface structure and the corrugated water channel design enable the heat dissipation performance of the neutron target to be better, so that the neutron target has a good application prospect in the field of boron neutron capture tumor treatment.

Description

Neutron target for boron neutron capture tumor treatment

Technical Field

The utility model relates to the field of boron neutron capture tumor treatment devices, in particular to a neutron target for boron neutron capture tumor treatment.

Background

Boron neutron capture therapy is a binary targeted tumor treatment method. After the tumor patient injects or takes the boron-containing medicament, the boron-containing medicament has strong affinity with tumor cells and is rarely attached to normal tissue cells. When a tumor of a patient is irradiated by a neutron beam, neutrons react with boron B10 in a nuclear way, and alpha particles generated by the nuclear reaction can release energy on a cell scale, so that tumor cells are killed. The neutron beam is usually used for accelerating protons or deuterium particles to a certain energy through an accelerator, and then the target is subjected to nuclear reaction to generate neutrons (usually, the proton beam is used for generating neutrons by beating a lithium target or a beryllium target), and the target for generating neutrons is called a neutron target. The neutron target is a subcomponent of a boron neutron tumor treatment device.

The generated neutrons are finally used for treating tumor patients, and the file IAEA TECDOC-1223 recommended by the International atomic energy organization IAEA gives the requirements of indexes such as the energy range, the emergent angle, the thermal neutron flux and the like of neutron beams for treating the patients by the boron neutron capture treatment device. Because the neutron energy emitted after passing through the neutron target is higher and does not reach the clinical treatment index yet, a set of neutron beam slowing shaping device (BSA) is usually required to be designed behind the neutron target, the energy of the neutron beam is reduced to the clinical treatment index requirement, and the emission angle of the neutron beam also needs to reach the clinical treatment index of the emission angle by adopting devices such as a reflector, a collimator and the like. Clinically, the more concentrated the angle of neutron exit is, the better. Many neutron target designs have some large angle scattering in the neutron space angular distribution, and the scattered neutrons need to be resolved by the reflective material of the beam slowing down shaping device BSA. Neutron sources for tumor treatment are typically produced by accelerating protons or deuterium by an accelerator, bombarding a lithium or beryllium target.

The lithium target has the advantages that the lithium target has higher neutron yield than the beryllium target under lower proton beam energy, the required proton beam energy is low, the manufacturing cost of an accelerator is also lower, the energy generated by neutrons is low, the energy interval required by treatment is more approximate, and the subsequent neutron slowing shaping device BSA is easier to design. However, the lithium target has a disadvantage in that the melting point of the lithium material is 180 deg.c lower, and a high-power proton beam is irradiated on the lithium target, which is easily melted. Therefore, the design of lithium targets is to solve the heat dissipation problem. The prior art scheme generally adopts a water cooling mode. Because the lithium target only needs about 100 microns, the maximum neutron yield can be basically achieved. The lithium target is thinner, and a copper support is needed for supporting and radiating, so that a water cooling system is usually filled in the copper support to improve the radiating effect. In addition, nuclear substances generated by nuclear reaction of the proton lithium target have certain radiation damage to the target, so that a layer of material for preventing foaming, usually a hydrogen storage material, needs to be added between the lithium target and the copper support.

In the prior art, the general design of neutron targets mainly comprises a solid target, a solid rotary target and a liquid target. In the case of proton irradiation schemes, the primary target material is essentially a lithium or beryllium target. The thickness is typically around 100 microns. The shape and structure of each design, the anti-foaming composite material, are different. In addition, water cooling schemes, such as water-filled copper brackets, are commonly used.

However, the prior art has mainly the following drawbacks: 1) The angular distribution of neutrons generated after a neutron target is poor, and some large-angle scattering exists, and even if the neutrons pass through a beam shaping device BSA, some large-angle scattering neutrons are lost and cannot be utilized; 2) The neutron target has weak heat dissipation capability, and the fixed target has weak heat dissipation capability even if the target material adopts a water cooling technology; 3) Part of the prior art does not have an interlayer anti-foaming material to avoid irradiation damage of the target.

Disclosure of Invention

The utility model aims to provide a neutron target for boron neutron capture tumor treatment, so as to solve the problems of poor angular distribution of neutrons generated by the neutron target and poor heat dissipation capacity of the neutron target in the prior art.

In order to solve the technical problems, the utility model adopts the following technical scheme:

providing a neutron target for boron neutron capture tumor treatment, wherein the neutron target is arranged between a proton beam outflow opening and a tumor patient, the neutron target is provided with a semi-tire-shaped curved surface structure capable of rotating around a central axis, the semi-tire-shaped curved surface structure extends between an inner annular edge and an outer annular edge, and a concave surface is formed towards the proton beam outflow opening and a convex surface is formed towards the tumor patient; the proton beam is always aligned to the concave surface of the neutron target, and along with the rotation of the neutron target around the central axis, the irradiation position of the proton beam on the concave surface is continuously changed.

Preferably, B/h=0.8 to 2.0, wherein B is the dimension of the neutron target in the axial direction, H is the radial dimension of one side of the neutron target, h= (D-D)/2, D is the outer diameter dimension of the outer ring of the neutron target, and D is the inner diameter dimension of the inner ring of the neutron target.

More preferably, the axial dimension B of the neutron target is less than 0.5, and the radial dimension h=1 of one side of the neutron target is less than effective. According to the research of the utility model, when the axial dimension B of the neutron target is: when the radial dimension H=1 of one side of the neutron target, the effect is good, and the problems of distribution of the neutron angle emitted by the neutron target and heat dissipation can be solved better.

The extending direction of the neutron target from the concave surface to the convex surface sequentially comprises the following steps: a core target layer, an anti-bubbling layer and a target base.

Preferably, a plurality of annular cooling water channels are arranged in the target base, and the centers of the annular cooling water channels are all positioned on the central shaft of the neutron target.

Preferably, two sides of the annular cooling water channel are respectively provided with 2-10 fold structures so as to enhance the heat dissipation effect.

Preferably, the height dimension of each fold structure is 0.5-6 mm, and the maximum width dimension of the annular cooling water channel is 0.5-6 mm.

Preferably, the arc length interval between the adjacent annular cooling water channels is 2-15 mm.

The core target material layer is a lithium layer or a beryllium layer; the anti-foaming layer is made of any one of lead, palladium, iron, niobium, tantalum and vanadium; the target base is made of any one of copper, aluminum, stainless steel, titanium and copper alloy materials, wherein the target base made of copper has the best effect.

Preferably, the outer diameter D of the outer ring is 600-1000 mm, and the inner diameter D of the inner ring is 200-500 mm.

Preferably, the thickness of the core target layer is 80-200 μm, most preferably 100 μm; the thickness of the anti-foaming layer is 40-60 mu m; the thickness of the target base is 10000-30000 mu m.

It should be understood that while the prior art also discloses solid rotary targets, the present utility model differs from the prior art in the shape, structure, and material selection of the targets. The present utility model does not contemplate a specific rotary machine configuration, but it should be understood that conventional machine configurations capable of effecting rotation of a neutron target are applicable to the present utility model.

According to the neutron target for boron neutron capture tumor treatment provided by the utility model, the following technical problems are mainly solved:

1) The problem of distribution of the outgoing neutron angles of the neutron target is solved. According to the requirement of boron neutron tumor treatment, the distribution of the angle of the emitted neutron beam is concentrated near 0 degree (central axis) as much as possible, and the more concentrated the emitted neutrons are, the higher the utilization rate of the neutrons is. Therefore, the neutron target should be designed so that the neutron space angle distribution emitted after proton or deuterium targeting is concentrated near 0 degrees as much as possible, and large-angle scattering is less likely to occur. Therefore, the design difficulty of BSA (beam slowing shaping device) behind the neutron target can be reduced, and the final neutron beam index is improved. In the prior art, the neutron emergent angles basically have large-angle scattering, and the design index needs to be achieved through the design of the reflector in the subsequent beam slowing shaping device BSA. Even with the reflector, a portion of neutrons are lost. The utility model solves the problem from the source, and the neutron angle distribution generated after the proton beam is targeted is concentrated near zero degrees. Therefore, the utility model solves the problem of poor neutron space angle distribution after passing through the target material in the prior art, obtains better angle distribution, and reduces the design difficulty of the subsequent BSA beam shaping device.

2) The problem of heat dissipation of the neutron target is solved. Neutron sources for tumor treatment are typically produced by accelerating protons or deuterium by an accelerator, bombarding a lithium or beryllium target. The lithium target has the advantages that the lithium target has higher neutron yield than the beryllium target under lower proton beam energy, the accelerator cost with low energy is lower, the energy generated by neutrons is low, the energy interval required by treatment is more approximate, the subsequent neutron slowing is easier, and the design of the neutron slowing shaping device BSA is easier. However, the lithium target has a disadvantage in that the melting point of the lithium material is 180 deg.c lower, and a high-power proton beam is irradiated on the lithium target, which is easily melted. Therefore, solving the problem of heat dissipation of the lithium target becomes critical. The present utility model solves this problem by three bright spots. The first bright point is that the lithium target adopts a curved surface design, so that the contact area between the proton beam and the lithium target is larger, and the heat dissipation is more facilitated. The curved surface design is innovative in that the curvature of the semi-tire-shaped curved surface and the like are strictly calculated, and the device achieves the optimal index by comprehensively considering heat dissipation and neutron space angle distribution. The temperature is also less than 180 ℃ of the melting point of lithium and is within the index range. The second bright point is that this neutron target has adopted rotary device, can let this curved surface target high-speed rotation for the beam can not strike on target material same point all the time, is favorable to solving the heat dissipation problem. The third bright point is that, this neutron target has also adopted the water-cooling technique of water injection in the copper of using commonly used, but its bright point lies in that we have adopted the fold shape water piping, and through calculating the temperature to learn, this kind of fold shape water piping design can promote cooling efficiency greatly, and the cooling effect is better than sharp water pipe, because the cooling water course designs into fold type and can increase the area of contact of rivers and copper, and the cooling effect is naturally better.

3) Solves the problem of foaming caused by irradiation damage of the target. The utility model solves this problem by means of a composite target. A layer of bubbling-preventing material is added between the lithium target and the copper holder, and other hydrogen storage materials such as palladium, iron, niobium, tantalum, iron, vanadium, etc. can be selected as the bubbling-preventing material.

Compared with the prior art, the neutron target for boron neutron capture tumor treatment provided by the utility model has the following remarkable beneficial effects:

1) The neutron angular distribution behind the neutron target is more concentrated. Because the neutron target adopts a curved surface design, the influence of the curvature of the curved surface on the distribution of the emergent neutron angles is accurately simulated and calculated, so that the three-dimensional distribution index of the neutron space after passing through the neutron target is better. In the case that the neutron moderating and shaping device BSA is not calculated yet, the neutron angle distribution index after passing through the neutron target only is obviously superior to that of the prior art. The neutron target has the advantage of spatial angular distribution of neutrons, and the curved surface structure of the half tire enables the neutron number of 0-45 degrees to be 2.14 times of that of the planar target with the same condition, and the neutron number of more than 90 degrees with the scattering angle to be only 0.38 times of that of the planar target with the same condition. Most neutrons are concentrated within 0-45 degrees in the design angle distribution, and the number of neutrons scattered at a large angle is small. Thus greatly reducing the design difficulty of BSA and greatly improving the utilization rate of neutrons.

2) The heat dissipation capability of the target is stronger. The present utility model improves heat dissipation through three aspects of design. Firstly, the target structure is a curved surface design, and the curved surface increases the contact area between proton beam and the target material, thereby improving the heat dissipation capacity; secondly, the neutron target is a rotary target and is a ring-shaped target which can rotate around the center of the ring, and after the target rotates, the beam current cannot irradiate on the same position for a long time, so that the heat dissipation capacity is improved; thirdly, the water channel of the neutron target adopts a fold design, so that the contact area of cooling water can be increased, and the heat dissipation capacity is improved.

3) And the composite multilayer target material is adopted, so that the bubbling is prevented, and the service life is prolonged. The target without the composite material interlayer in the middle is used for a period of time due to radiation damage of nuclear reaction waste, the target is easy to foam and fall off, and the service life is short.

In summary, the neutron target for boron neutron capture tumor treatment provided by the utility model has the advantages of more concentrated neutron angular distribution, stronger heat radiation capability and longer service life, and the inventor also calculates the temperature and neutron angular distribution of each material by adopting the Monte Card to simulate the irradiation neutron target of 2.5MeV,20mA proton beam, thereby proving that the neutron target has better heat radiation capability and neutron angular distribution compared with the prior art.

Drawings

FIG. 1A is a schematic diagram of a structure of a comparative technique I (planar pure lithium target);

FIG. 1B is a schematic diagram of a structure of a comparative technique II (planar copper-bearing-water-injected lithium target);

FIG. 2 is a schematic illustration of the use of a neutron target provided in accordance with a preferred embodiment of the utility model for boron neutron capture tumor therapy;

FIG. 3 is a schematic diagram of the neutron target in its individual configuration;

FIG. 4A is a front view of the neutron target;

FIG. 4B is a side view of the neutron target;

FIG. 5 is an axial cut-away view of the neutron target, showing the detailed construction of the corrugated cooling water channel;

FIG. 6 is a radial cut-away view of the neutron target;

FIG. 7A is a comparison of the energy spectrum analysis of a comparative technique one plane pure lithium target solution A, a comparative technique two plane copper-impregnated support lithium target solution B, and a semi-tire-shaped curved surface rotary lithium target solution C of the present utility model;

FIG. 7B is a comparison of the spatial radian distribution of a comparative technique-pure lithium target solution A, a comparative technique biplane copper-filled-water-bearing lithium target solution B, and a semi-tire-shaped curved surface rotating lithium target solution C of the present utility model;

FIG. 7C is a comparison of spatial angular distributions of a comparative technique-pure lithium target scheme A, a comparative technique biplane copper-filled-water-bearing lithium target scheme B, and a semi-tire-shaped curved surface rotary lithium target scheme C of the present utility model;

FIG. 8 is a graph showing the steady-state temperature distribution of a material under irradiation with proton beam parameters for boron neutron capture therapy, comparing the results of heat dissipation performance analysis of a two-plane copper-filled lithium-bearing target solution B; wherein A is a lithium layer, B is a lead layer, and C is a copper layer;

FIG. 9 is a graph showing the results of analysis of the heat dissipation performance of a semi-tire shaped curved surface rotary lithium target solution C of the present utility model, showing the steady-state temperature distribution of the material under irradiation with proton beam parameters employed in boron neutron capture therapy; wherein A is a lithium layer, B is a lead layer, and C is a copper layer.

Detailed Description

The utility model will be further illustrated with reference to specific examples. It should be understood that the following examples are illustrative of the present utility model and are not intended to limit the scope of the present utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

In order to more clearly demonstrate the technical solution of the present utility model, two contrasting technical solutions are provided here to facilitate the contrast. Wherein fig. 1A shows a comparative technique one: a planar pure lithium target 100, fig. 1B shows a comparative technique two: a planar copper-impregnated backing lithium target 200. It should be appreciated that planar pure lithium targets are used as a comparative example only, and that pure lithium is not generally used in practice, and that pure lithium is also liquid pure lithium. As can be seen from the figure, the planar pure lithium target 100 is a sheet-like neutron target made of pure lithium, having a thickness of 100 μm, a height of 120mm, and a width of 120mm; the planar copper-filled support lithium target 200 is a composite neutron target consisting of a lithium layer and a copper-filled support, and has a thickness of 20mm, a height of 120mm, and a width of 120mm. The performance studies on these two comparative solutions will be explained later.

According to a preferred embodiment of the present utility model, there is provided a neutron target 10 for boron neutron capture tumor treatment, as shown in fig. 2 and 3, the neutron target 10 being disposed between a proton beam 20 and a tumor patient 40, the entire neutron target 10 being enclosed by a beam slowing down shaping device 30 (it being understood that the neutron target 10 and the beam slowing down shaping device 30 are depicted separately for convenience of illustration), the neutron target 10 having a semi-tire-like curved surface structure rotatable about a central axis a, with its concave surface 11 facing the proton beam 20 and its convex surface 12 facing the tumor patient 40 in use; the proton beam 20 is always aligned to the concave surface of the neutron target 10, along with the rotation of the neutron target 10 around the central axis A, the irradiation position of the proton beam 20 on the concave surface 11 is continuously changed, the proton beam 20 strikes the neutron target 10 to generate neutrons, and the neutrons irradiate the tumor of the tumor patient 40 after passing through the beam slowing shaping device 30 and undergo nuclear reaction with the boron-containing medicament to treat the tumor. As the target rotates, the material at the top of the beam irradiating neutron target is constantly changing, making one revolution into one cycle.

As shown in fig. 3, 4A and 4B, the neutron target 10 has a generally toroidal configuration, similar to a half tire, with a semi-toroidal configuration extending between an inner annular rim and an outer annular rim to form a concave 11 on one side and a convex 12 on the other side. According to the neutron target 10 provided in this preferred embodiment, the inner diameter dimension D of the inner ring is 440mm, the outer diameter dimension D of the outer ring is 760mm, the overall neutron target 10 has an axial dimension B of 160mm, the neutron target has a single-sided radial dimension h= (D-D)/2= (760-440)/2=160 mm, and the neutron target has an axial dimension B: a single-sided radial dimension h=1:1.

It should be understood, however, that the ratio of the axial dimension B to the one-sided radial dimension H of the neutron target is not limited to 1:1, but in practice, the ratio of the axial dimension B to the one-sided radial dimension H of the neutron target is preferably 0.8 to 2.0, and outside this range, such as less than 0.5, is less effective.

As shown in fig. 5, the neutron target 10 includes, in order from the concave surface 11 to the convex surface 13: the neutron target comprises a core target layer 13, an anti-bubbling layer 14 and a copper layer 15, wherein the core target layer 13 is a lithium layer, the anti-bubbling layer 14 is a lead layer, a plurality of annular cooling water channels 16 are arranged in the copper layer 15, and the centers of the annular cooling water channels 16 are positioned on a central axis A of the neutron target 10. As shown in fig. 6, each small square hole in the radial cut of the neutron target represents an annular cooling water channel 16.

According to the preferred embodiment, both sides of the annular cooling water channel 16 have 3 corrugated structures, respectively, to enhance the heat dissipation effect thereof. The width of each cooling water channel 16 was 2mm, the two sides of the corrugated portion were each projected by 0.5mm, the total width was 3mm, the height dimension of the annular cooling water channel 16 was 3mm, and the arc length spacing between adjacent cooling water channels 16 was 9.5mm.

It should be understood that the above dimensions are by way of example and not limitation, and that in practice, each side of the annular cooling gallery may have 2 to 10 pleat structures to enhance its heat dissipation. The height dimension of the annular cooling water channel is 0.5-6 mm, and the maximum width dimension is 0.5-6 mm. The arc length interval between adjacent cooling water channels is 2-15 mm.

According to this preferred embodiment, the core target layer 13 in contact with the beam is a lithium layer with a thickness of 100 μm, the anti-bubbling layer 14 is a lead layer with a thickness of 50 μm, the outermost copper layer is 19850 μm, and the total thickness of all materials is 2cm.

It should be understood that the above materials and dimensions are by way of example and not limitation, the core target layer may be selected to be a lithium layer or a beryllium layer, and the anti-blister layer may be made of any of lead, palladium, iron, niobium, tantalum, vanadium. Preferably, the thickness of the core target layer is 80-200 μm; the thickness of the anti-foaming layer is 40-60 mu m; the thickness of the copper layer is 10000-30000 mu m.

Example 1 neutron angular distribution contrast

In order to prove that the neutron angle distribution emitted after the neutron target is more concentrated near 0 degrees, the embodiment bombards the neutron target of the three schemes by simulating and calculating the proton beam of 2.5MeV, and realizes the energy spectrum comparison, the spatial radian angle distribution comparison and the solid angle comparison of a pure lithium target scheme A, a planar copper-containing water-injection lithium-bearing target scheme B and a semi-tire-shaped curved surface rotary lithium target scheme C.

The results are shown in fig. 7A-7C, and it can be seen from fig. 7A that the neutron spectrum distribution is close in the three schemes. The main difference is the spatial angular distribution of the exiting neutrons, as can be seen from the spatial stereo angular distribution of fig. 7C, the spatial stereo angular distribution of the scheme C of the present utility model has far more small angle neutrons than the schemes a and B, and the large angle scattered neutrons greater than 90 degrees are far less than the schemes a and B. The curved surface structure of the half tire of the utility model ensures that the neutron number of 0-45 degrees is 2.14 times of that of the planar target under the same condition, and the neutron number of more than 90 degrees with a scattering angle is only 0.38 times of that of the scheme B. This also demonstrates that the neutron target is better than the traditional planar target neutron angle distribution technical index.

Example 2 comparison of Heat dissipation Properties

In order to prove that the heat radiation performance of the semi-tire-shaped curved surface rotary lithium target is better, the embodiment realizes the target heat radiation performance comparison of the planar water injection copper-bearing lithium target scheme B and the semi-tire-shaped curved surface rotary lithium target scheme C by simulating and calculating the steady-state temperature distribution of the 2.5MeV proton beam bombarding neutron target.

As a result, as shown in fig. 8 and 9, the highest temperature of the lithium layer of the half-tire-shaped curved surface rotary lithium target scheme C is 122.54 ℃, the highest temperature of the lithium layer of the planar water-injection copper-bearing lithium target scheme B is 185.29 ℃, and it is apparent that the heat dissipation performance of the half-tire-shaped curved surface rotary lithium target scheme C is significantly higher than that of the planar water-injection copper-bearing lithium target scheme B of the comparative technology.

It should be appreciated that scheme B exceeds the melting point, possibly with more of their water cooling configuration. The temperature compared at present is also only a static temperature, not including a dynamic temperature of the rotation of the lithium target, and the temperature after the rotation of the lithium target of the present utility model is lower in consideration of the rotation and the different rotation speeds. The temperature of the steady state equilibrium state is calculated in this embodiment, and only the equilibrium state reaches the index requirement under the condition that the rotation transient temperature is not considered yet.

The foregoing description is only a preferred embodiment of the present utility model, and is not intended to limit the scope of the present utility model, and various modifications can be made to the above-described embodiment of the present utility model. All simple, equivalent changes and modifications made in accordance with the claims and the specification of the present application fall within the scope of the patent claims. The present utility model is not described in detail in the conventional art.

Claims (11)

1. A neutron target for boron neutron capture tumor treatment, which is arranged between a proton beam outflow port and a tumor patient, and is characterized in that the neutron target is provided with a semi-tire-shaped curved surface structure capable of rotating around a central shaft, the semi-tire-shaped curved surface structure extends between an inner annular edge and an outer annular edge, and a concave surface is formed towards the proton beam outflow port and a convex surface is formed towards the tumor patient; the proton beam is always aligned to the concave surface of the neutron target, and along with the rotation of the neutron target around the central axis, the irradiation position of the proton beam on the concave surface is continuously changed.

2. The neutron target for boron neutron capture tumor therapy of claim 1, wherein B/H = 0.8-2.0, wherein B is the axial dimension of the neutron target, H is the unilateral radial dimension of the neutron target, h= (D-D)/2, D is the outer diameter dimension of the outer ring of the neutron target, and D is the inner diameter dimension of the inner ring of the neutron target.

3. The neutron target for boron neutron capture tumor treatment of claim 1, wherein the direction of extension of the neutron target from concave to convex comprises, in order: a core target layer, an anti-bubbling layer and a target base.

4. The neutron target for boron neutron capture tumor treatment of claim 3, wherein a plurality of annular cooling water channels are arranged in the target base, and the centers of the annular cooling water channels are all positioned on the central axis of the neutron target.

5. The neutron target for boron neutron capturing tumor treatment of claim 4, wherein 2-10 fold structures are respectively arranged on two sides of the annular cooling water channel so as to enhance the heat dissipation effect.

6. The neutron target for boron neutron capturing tumor treatment of claim 5, wherein the height dimension of the individual corrugated structures is 0.5mm-6mm, and the maximum width dimension of the annular cooling water channel is 0.5-6 mm.

7. The neutron target for boron neutron capture tumor therapy of claim 4, wherein the arc length spacing between adjacent annular cooling water channels is 2-15 mm.

8. The neutron target for boron neutron capture tumor treatment of claim 3, wherein the core target material layer is a lithium layer or a beryllium layer; the anti-foaming layer is made of any one of lead, palladium, iron, niobium, tantalum and vanadium; the target base is made of any one of copper, aluminum, stainless steel, titanium and copper alloy materials.

9. The neutron target for boron neutron capture tumor treatment of claim 2, wherein the outer ring has an outer diameter dimension D of 600-1000 mm and the inner ring has an inner diameter dimension D of 200-500 mm.

10. The neutron target for boron neutron capture tumor treatment of claim 3, wherein the thickness of the core target layer is 80-200 μm; the thickness of the anti-foaming layer is 40-60 mu m; the thickness of the target base is 10000-30000 mu m.

11. The neutron target for boron neutron capture tumor therapy of claim 10, wherein the thickness of the core target layer is 100 μιη.

Images