CN-122000107-A - Combined neutron beam line device

CN122000107ACN 122000107 ACN122000107 ACN 122000107ACN-122000107-A

Abstract

The invention discloses a composite neutron beam line device which comprises a composite beam line and a composite shielding wall, wherein the composite beam line is used for improving two original independent beam lines before compositing into a beam line which is partially independent and partially shared after compositing, the composite shielding wall is used for improving the two independent shielding walls before compositing into a shielding wall which is partially independent and partially shared after compositing, and the composite neutron beam line device which can simultaneously generate quasi-monoenergetic neutrons and white-light neutrons and only generate quasi-monoenergetic neutrons and white-light neutrons is formed by matching the composite beam line and the composite shielding wall.

Inventors

LI XIAOBO
ZHAO YUNLONG
WEI SUMIN
WANG ZHE
WANG FEI
ZHU PENGFEI
JI BIN
LIU JIE
AN SHIZHONG
GUAN FENGPING

Assignees

中国原子能科学研究院

Dates

Publication Date: 20260508
Application Date: 20260130

Claims (7)

1. A composite neutron beam line device is characterized by comprising a composite beam line and a composite shielding wall, wherein the composite beam line is used for improving two original independent beam lines before compositing into a beam line which is partially independent and partially shared after compositing, the composite shielding wall is used for improving the two independent shielding walls before compositing into a shielding wall which is partially independent and partially shared after compositing, and the composite beam line and the composite shielding wall are matched to form the composite neutron beam line device capable of simultaneously generating quasi-mono-energy neutrons and white light neutrons, the composite neutron beam line device capable of only generating quasi-mono-energy neutrons and the composite neutron beam line device capable of only generating white light neutrons, and the two beam lines are quasi-mono-energy neutron beam lines and white light neutron beam lines.
2. The composite neutron beam device according to claim 1, wherein the original independent two beam lines before the composite are modified into a part of independent and part of beam lines after the composite are shared, namely, the composite beam line reduces two focusing magnets on the two beam lines before the composite into a shared focusing magnet (1) after the composite, a quasi-single-energy neutron target and a white-light neutron target which are in time-sharing operation on the two beam lines before the composite are changed into a quasi-single-energy neutron target (3) and a white-light neutron target (5) which are in simultaneous operation after the composite, three Faraday cylinders on the two beam lines before the composite are reduced into two Faraday cylinders after the composite, and two deflection magnets on the two beam lines before the composite are modified into a shared deflection magnet (4) after the composite.
3. The composite neutron beam line device of claim 1, wherein the composite shielding wall is characterized in that the two independent shielding walls before the composite are improved to be partially independent and partially shared shielding walls after the composite, specifically, the white light neutron target before the composite and the white light neutron target shielding wall are moved to the exit of the quasi-mono-energy neutron target beam deflection magnet (4), the white light neutron target shielding wall and the quasi-mono-energy neutron target shielding wall are overlapped, the upper edge of the white light neutron target shielding wall and the inner edge of the quasi-mono-energy neutron target shielding wall close to the beam outlet side of the beam deflection magnet are flush, and the shielding wall at the overlapped part is a shielding wall which is saved compared with the two independent beam line shielding walls.
4. The composite neutron beam device according to claim 1, wherein the focusing magnet (1), the first Faraday cylinder (2) and the quasi-unienergy neutron target (3) are sequentially arranged on the beam inflow port side of the deflection magnet (4) along the proton beam direction, and the second Faraday cylinder (5) and the white light neutron target (6) are sequentially arranged on the beam outflow port side of the deflection magnet (4) along the proton beam direction.
5. The device of claim 4, wherein the cross section of the first Faraday cylinder (2) and the second Faraday cylinder (5) is in a state of shielding proton beam or collecting proton beam in a proton beam intensity detection stage, and the cross section of the first Faraday cylinder (2) and the second Faraday cylinder (5) is in a state of lifting or laterally moving to allow proton beam to pass in a state of producing quasi-mono-energy neutrons and white light neutrons simultaneously.
6. The composite neutron beam device according to claim 4, wherein the composite neutron beam device only generates quasi-monoenergetic neutrons, and specifically, in a proton beam intensity detection stage, the cross sections of the first Faraday cylinder (2) and the second Faraday cylinder (5) are in a state of collecting proton beams, in a stage of only generating quasi-monoenergetic neutrons, the cross section of the first Faraday cylinder (2) is in a state of lifting and passing proton beams, and the cross section of the second Faraday cylinder (5) is in a state of shielding proton beams from passing proton beams.
7. The composite neutron beam device according to claim 4, wherein the composite neutron beam device only generates white light neutrons, the cross sections of the first Faraday cylinder (2) and the second Faraday cylinder (5) are in a state of collecting proton beams in a beam intensity detection stage, the first Faraday cylinder (2) is in a state of lifting and allowing proton beams to pass through in a state of only generating white light neutrons, the second Faraday cylinder (5) is in a state of laterally moving and allowing proton beams to pass through, and the quasi-mono-energy neutron target is also in a state of lifting and allowing proton beams to pass through in a state of only generating white light neutrons, and the beam does not pass through the quasi-mono-energy neutron target (3) any more, but directly passes through the deflection magnet (4) and the white light neutron target (6) to generate white light neutrons.

Description

Combined neutron beam line device Technical Field The invention belongs to the technical field of neutron beam line devices, and particularly relates to a composite neutron beam line device. Background Neutrons are one of basic component particles of atomic nuclei, have electric neutrality, magnetic moment and strong penetrating power, can accurately distinguish light elements, isotopes and adjacent elements, and are a unique and irreplaceable advanced tool in the front-edge scientific research. Meanwhile, in the fields of radiation biological effect research, neutron cancer treatment, neutron activation analysis, neutron imaging, nondestructive detection, isotope production and the like, neutron technology is increasingly deep into daily life of people, and wide application value is shown. The neutron source based on the accelerator is an important facility for current neutron science and application, has the advantages of high pulse flux, flexible operation, low safety risk and the like, and has outstanding potential in the aspects of dynamic process research, multidisciplinary cross application and medical industrialization. Quasi-mono-energy neutrons and white light neutrons generated by neutron sources based on medium-high energy accelerators are of great importance in practical applications. The energy of quasi-monoenergetic neutrons is concentrated in a narrow interval and is mainly used for applications such as detector calibration, device irradiation effect research, shielding material performance test and the like. The energy spectrum of white light neutrons continuously covers a wider range and plays an important role in imaging and nondestructive detection, isotope production, neutron activation analysis and the like. One of the problems in the design, construction and application processes of the quasi-single-energy neutron beam line and the white-light neutron beam line at present is that the two beam lines cannot be used simultaneously. When two beam lines are built based on the same accelerator, protons are accelerated to a certain energy in the accelerator, and then enter one of the two beam lines according to practical application to bombard a target material to generate neutrons and put into application. Thus, if the same accelerator is used, only one beam line can be used at a time. The second problem in the design, construction and application processes of the quasi-single-energy neutron beam line and the white-light neutron beam line at present is that when the quasi-single-energy neutron beam line is applied, only a very small number of protons are utilized, most of protons are wasted, and the wasted protons also increase the cost of a shielding wall specially designed for the quasi-single-energy neutron beam line. The reason is that, due to the consideration of neutron monochromaticity, the quasi-monoenergetic neutron target sheet made of lithium or beryllium is very thin, protons only deposit about 2 MeV of energy in the quasi-monoenergetic neutron target sheet, most of protons which do not participate in neutron production reaction pass through the target sheet and then are close to an initial value, and the protons are required to be led out to a beam current collecting barrel through a deflection magnet for measurement, blocking and collection. Therefore, the blocked and collected protons are not only wasted, but also react with the beam collector to generate a large amount of stray neutrons to affect the original experimental effect. To avoid this effect, a shielding structure is required to block the neutrons, and the shielding effect is better when the beam dump is positioned deeper in the shielding structure, but the size of the shielding structure becomes larger as a result of deep shielding, and the space cost for installation and the shielding material cost are increased. The third problem in the design, construction and application processes of the quasi-single-energy neutron beam line and the white-light neutron beam line at present is that when the two beam lines are independently constructed, the material cost and the space cost are obviously increased. Two beam lines need two sets of deflection magnets, two sets of focusing magnets and two sets of shielding structures. The cost of one set of deflection magnet is about 80 ten thousand, the space is 2 square meters, the cost of one set of focusing magnet is about 20-30 ten thousand, the space is 1 square meter, and the cost of one set of shielding structure is about 10 ten thousand, the space is 4-5 square meters; Disclosure of Invention The invention provides a composite neutron beam line device for solving the defects of the prior art, which aims at solving the problem that two beam lines cannot be used simultaneously in the prior art, and aims at solving the problems that when a quasi-single-energy neutron beam line is applied, only a very small number of protons are utilized, most of the protons are wasted, most of