52 results about "Neutron yield" patented technology

The invention discloses a pulsed neutron generator control system based on LabVIEW, and the system comprises a neutron generator industrial personal computer which operates a virtual human-computer interaction interface developed based on LabVIEW; the console core board carries a DSP main control chip and is embedded into a real-time operating system; the driving sampling board is connected with the console core board and is integrated with a signal conditioning circuit; the neutron generator industrial personal computer communicates with the console core board through a Modbus protocol, and controls and drives the sampling board to output control signals of the three independent power supply ion sources, the storage and the acceleration pole to the neutron tube; wherein the console core board generates three paths of PWM signals with the PWM frequency of 2.5 kHz and the step length of 8191, and the three paths of PWM signals are converted into analog control signals through the driving sampling board. According to the control system, the PWM control precision is greatly improved, the voltage control precision is improved to 0.012% (100% higher than that of a conventional scheme) through the combination of the 8191 step length (13-bit resolution) and the 2.5 kHz frequency, and the neutron yield fluctuation is controlled within + / -1.5%.

The invention provides a rotating target for generating monoenergetic neutrons, which comprises a target chamber, a target sheet, a sealing flange and a vacuum system, the target sheet is composed of a TiD / TiT target material and a substrate, a deviation distance of 5-10mm exists between the center of the target material and the center of the substrate, the substrate is connected with a motor outside the target chamber through a fixed connecting rod, and the target chamber is driven by the motor to rotate at a speed of 3-5min / r. The target material is designed to be the eccentric target rotating slowly, so that the utilization rate of the target material can be improved, and the phenomena that the temperature of a single point is too high, a coating layer penetrates or falls off, enriched gas escapes and neutron yield fluctuation is caused due to the fact that beam bombards one position of the target material for a long time can be avoided. The energy width of neutrons generated by the rotating target is lower than 5%, the rotating target has good monochromaticity and low energy loss, the design precision requirement of the fourth-generation nuclear reactor can be met, and a possible guarantee is provided for commercialized popularization and application of the fourth-generation nuclear reactor.

This invention discloses a conveniently detachable, actively water-cooled solid-state deuterium target based on a compact neutron source, comprising a micron-sized solid titanium film, a titanium film carrier, and a water-cooled substrate. Deuterium is deposited in the solid titanium film by bombarding it with a deuterium ion beam, and neutrons are generated by collisions with the subsequent deuterium ion beam. Oxygen-free copper, with its high thermal conductivity, is used as the carrier for the titanium film. The threaded structure on the side of the titanium film carrier allows for convenient installation and removal from the water-cooled substrate. The oxygen-free copper substrate, with multiple annular water-cooling structures inside, enables rapid and effective removal of heat flux from the target, preventing deuterium particles deposited in the solid titanium film from desorbing due to excessive temperature, thus avoiding impact on neutron yield. This invention provides a conveniently detachable, actively water-cooled solid-state deuterium target suitable for compact deuterium-deuterium neutron generators, providing a sound technical foundation for the widespread application of compact accelerator neutron source systems in production and daily life.

A rotating target high yield compact D-D neutron generator disclosed by the present invention comprises an ion source unit, a vacuum main body unit and a target unit, the ion source unit generates a deuterium ion beam, the deuterium ion beam is introduced into a vacuum chamber and passes through a leading-out accelerating electrode for acceleration, and the accelerated deuterium ion beam bombards the circumferential target surface of a molybdenum target to generate a deuterium ion beam. And deuterium-deuterium fusion reaction with deuterium nuclei injected into the molybdenum target in advance is carried out, fast neutrons are released, and the neutron yield is improved. The rotating driver of the target unit drives the molybdenum target of the cylindrical structure to rotate through the insulating rotating shaft, the molybdenum target rotates to distribute beam power to the circumferential target surface of the molybdenum target, a cooling medium is conveyed to one side of the inner side wall of the molybdenum target in combination with the cooling channel, the molybdenum target is cooled, and the service life of the target unit can be effectively prolonged. The leading-out accelerating electrode is located in the vacuum cavity, operation of the vacuum main body unit is not affected by external humidity and temperature environment conditions, high-voltage ignition discharge can be effectively restrained, and the safety performance of a high-voltage electric field is improved.

The present invention relates to the technical field of neutron targets and discloses a tantalum and beryllium neutron target system suitable for BNCT. The tantalum and beryllium neutron target system comprises a target plate structure and a target stand for mounting the target plate structure. The target plate structure comprises a tantalum target and a beryllium target, which are bonded into an integrated target plate structure by a high-temperature resistant metal adhesive. The tantalum and beryllium neutron target system suitable for BNCT provided by the present invention solves the problem of low energy utilization and inability to maximize neutron yield in existing designs.

The invention relates to the technical field of solid-state lithium target water cooling, in particular to a water-cooling supporting device for a boron neutron capture therapy solid-state lithium target. According to the technical scheme, the water cooling device comprises a water cooling base providing support, an inclination angle supporting support is installed on the top of the water cooling base, the section of the inclination angle supporting support is of a right triangle structure, a structural material is installed on the bevel edge of the inclination angle supporting support, and a cooling assembly is arranged on the structural material; a heat sink material is fixedly installed on the side, away from the dip angle supporting support, of the structural material, and cooling channel ribs are evenly arranged on one side of the heat sink material. The whole structure is compact, the heat removal problem of the accelerator neutron source BNCT solid-state lithium target can be simply, conveniently and efficiently solved, continuous, safe and stable operation of a neutron source system is guaranteed, the requirement for high-flux neutron yield is met, and the problems that the solid-state lithium target is short in service life due to lithium film evaporation, melting and the like and the target structure is unstable due to heating can be effectively solved.

The application discloses a high-extraction-efficiency ion source structure and sealed neutron tube structure; a TiT thin film target is tightly attached to the inner wall of a closed shell; a target grid is tightly attached to the TiT thin film target, and a negative bias voltage is generated by loading a voltage between the target grid and the closed shell; plasma is generated after a voltage is loaded between a discharge anode and a discharge cathode; the scheme is based on the existing vacuum arc discharge ion source structure and is improved in structure; space is reserved between the discharge cathode and the anode grid for free expansion of the plasma, an open expansion space is provided for the plasma, most of the plasma generated by the discharge can expand into the acceleration zone to obtain energy and bombard the target surface, so that the arc current utilization rate can be increased to about 1%, and the neutron yield can be broken through 1*10 10 n / s.

The present application relates to a method for generating a pulsed neutron source based on a dual-beam laser-driven ultra-thin target. The method comprises: setting an ultra-thin target in the center of a pulsed neutron source device, and simultaneously vertically incident two laser beams from the left and right boundaries of the pulsed neutron source device to generate a laser neutron source; by changing the rotation direction and relative phase difference of the electric field vectors of the two laser beams, the neutron yield of the neutrons generated by the laser neutron source is manipulated, and directional emission of neutrons is achieved. The present invention greatly broadens the use scenarios and application potential of the generated pulsed neutron source.

The invention discloses a neutron beam real-time regulation and control method and system based on two parameters, and the method comprises the steps: collecting the two parameters and a target beam current in real time, and obtaining a data set; an LSTM-Attention initial model is constructed; training, verifying and testing the LSTM-Attention initial model by using the training set, the verification set and the test set to obtain a final neutron beam current control model; the deviation between the target beam current and a set value is monitored in real time, a final neutron beam control model is used for inversion to obtain a two-parameter adjusting quantity, and real-time neutron beam regulation and control are achieved; according to the method, the coupling relation between the two parameters and the beam is considered, the current and the air inflow of the ion source can be adjusted in real time, stable operation of the neutron source beam is ensured, the neutron yield stability is improved, and the application effect in practical application can be improved.

The invention discloses a uranium mine logging instrument based on ultrashort pulse neutrons and a working method thereof, and relates to the field of uranium mine exploration logging. The logging instrument comprises a control communication short section, an ultrashort pulse neutron generator used for emitting fast neutron pulses with the pulse width smaller than 1 microsecond to a stratum, a shielding body and a double-thermal-neutron detection assembly used for detecting thermal neutrons and epithermal neutrons on measuring points consistent in space, all of which are sequentially arranged in the axial direction of the logging instrument. The gamma detector is used for detecting inelastic scattering gamma rays emitted by stratum elements and capturing gamma rays, and the fast neutron detector is used for detecting and outputting source intensity monitoring signals of fast neutron pulses in real time. According to the logging instrument, the ultra-short fast neutron pulse is emitted, the neutron yield is detected in real time, the neutron time spectrum and gamma-ray energy spectrum multi-dimensional information with an accurate timestamp are obtained in a combined mode, high-precision and anti-interference inversion is conducted on the stratum uranium content, and stratum information is obtained efficiently and accurately.

The invention discloses an ultrahigh-yield gaseous target neutron tube and an installation method thereof in the technical field of neutron tubes, and the neutron tube comprises a shell, a heating excitation assembly, an acceleration assembly and a target receiving assembly, the heating excitation assembly is installed at the lower end of the shell, and the acceleration assembly is located in the shell; the input end of the acceleration assembly corresponds to the output end of the heating excitation assembly, and the target receiving assembly is installed at the upper end of the shell. According to the invention, the acceleration electrode is arranged to be in the conical table shape, the size of the inlet of the acceleration electrode is increased, the length of the acceleration electrode is shortened, and a proper acceleration electric field can be formed; a grid mesh output hole structure is adopted, and the aperture ratio of a grid mesh framework is adjusted, so that the ion transmittance is the maximum value, and a relatively large ion current can be obtained; by arranging the improved grid mesh and the improved acceleration pole, a large amount of neutrons are output, so that the yield of the super-high-yield gaseous target neutron tube can reach more than 1 * 1010n / s, and the problem that the neutron yield of an existing neutron tube is relatively low is solved.

The invention discloses a laser neutron yield increasing method based on a composite conversion target, which comprises the following steps of: arranging a plurality of elements to form the composite conversion target, bombarding the composite conversion target by using a deuterium ion beam obtained by interaction of laser and a heavy water liquid film target, and realizing neutron yield increasing through nuclear reaction section optimization; elements in the composite conversion target comprise at least two of T, D, < 7 > Li and < 9 > Be. According to the laser neutron yield increasing method based on the composite conversion target, the neutron yield and the average flux of a repetition frequency laser neutron source method are greatly increased, and the problem of instability in the continuous production process of a heavy water liquid film target is solved.

The invention discloses a solid neutron source device with potential diversion and magnetic field screening functions and a control method. The device comprises an ion generation structure, a potential diversion structure, a magnetic field screening structure, a neutron target and an insulating shell, the ion generation structure generates mixed ions under the action of the outside, the mixed ions form regular beams under the action of the potential diversion structure and enter the magnetic field screening structure, and due to the fact that different ions show different motion characteristics in a magnetic field, screening is carried out through an insulation pole plate with long rectangular holes. And finally, ion receiving and neutron excitation are completed under the action of strong potential carried by the neutron target. According to the invention, the loss caused by ion generation is effectively controlled through a potential diversion structure, and the utilization efficiency of ions and the neutron yield are improved by adopting a control method that the potential is continuously adjustable. Meanwhile, through a magnetic field screening structure, effective separation and screening of mixed ions are achieved, a control method with a continuously adjustable magnetic field is adopted, the screening range is wide, and the service life of a neutron source is prolonged.

A plasma focus system for neutron production is disclosed that includes a plasma focus device and a neutron source. The plasma focus device is configured to emit a remnant ion beam. The neutron source includes an enclosure having a cavity formed therein for receiving a target medium. Depending on the application, the target medium can be a gas, a liquid, or a solid. The enclosure includes a beam entrance port configured to allow at least part of the remnant ion beam to enter and travel inside the cavity. As the remnant ion beam travels along the cavity, the beam ions interact with the target medium and undergo both fusion collisions and non-fusion collisions. The fusion collisions produce neutrons and reduce a number of the beam ions, while the non-fusion collisions reduce an energy of the beam ions. A plasma focus method of neutron production is also disclosed.

The present invention provides a laser fusion cross-scale simulation method, system, and terminal based on relay computing. The method utilizes a radiation fluid program to simulate the nanosecond laser-driven fuel implosion collision process, obtaining the post-collision plasma temperature and density distribution. A particle kinetics program is used to simulate the picosecond laser-driven fast electron generation process, obtaining the fast electron beam distribution in phase space. The obtained post-collision plasma temperature and density distribution, as well as the fast electron beam distribution in phase space, are then input into a hybrid kinetics program to simulate the fast electron beam heating process of the colliding plasma, obtaining the colliding plasma heating results. The radiation fluid program is then used to simulate the fusion combustion process based on the colliding plasma heating results, obtaining the neutron yield and fusion energy gain. The present invention utilizes numerical simulation methods at different physical scales to calculate the corresponding physical processes, and couples these different physical processes for relay computing, achieving cross-scale simulation of laser fusion schemes while ensuring controllable computational accuracy and computational complexity.

The invention belongs to the technical field of data processing, and relates to a neutron generator operation state monitoring method and system based on digital twinning. The method comprises the following steps: acquiring real-time operation electrical parameters to construct a virtual twinborn body; inverting the effective deuterium and tritium atom concentration in the target film in real time by using a physical difference equation containing a particle injection item and a thermal diffusion loss item; a beam spot drift correction factor is determined by calculating the difference between the real-time impedance of the neutron tube and the nominal design impedance, the beam spot area of the virtual twin is dynamically corrected, and the problem of prediction model failure caused by electrode ablation is solved; and finally, on the basis of the corrected state parameters, using a multi-parameter product model to predict the neutron yield and perform health degree diagnosis. Transparent monitoring of the internal state of the neutron tube is achieved, the problem of model distortion caused by beam spot drift is effectively solved, and the prediction precision of the whole life cycle is improved.

The invention relates to an accurate stabilization method for the neutron yield of a neutron generator and the neutron generator, and belongs to the technical field of neutron yield control. The accurate stabilization method for the neutron yield of the neutron generator comprises the following steps: executing a first-stage feedback control loop and a second-stage feedback control loop at the same time; the first-stage feedback control ring is configured to control the actual measurement value of the beam to be stabilized to the beam set value by adjusting the microwave power or / and the gas flow according to the deviation between the actual measurement value of the beam and the beam set value; the control period of the first-stage feedback control loop is from millisecond level to second level; the second-stage feedback control loop is configured to determine the variation required by the beam current set value according to the deviation between the actual measurement value of the neutron yield and the neutron yield set value, and update the beam current set value; and the control period of the second-stage feedback control loop is from a second stage to a hundred seconds stage. According to the accurate stabilization method for the neutron yield, long-term accurate and stable control of the neutron yield can be realized, and the response speed is high.

The present application discloses a compact neutron generator based on an all-glass helicon wave ion source, which belongs to the field of accelerator neutron sources. The neutron generator includes a helicon wave ion source part, a cavity part, and a target part. First, deuterium gas is introduced into the ion source chamber. Then, the deuterium gas is excited by an antenna, thereby generating a helicon wave plasma. Under the constraint of a magnetic field, deuterium ions are first extracted in the form of a beam by the potential difference between an extraction electrode and an ion source cover plate, and then accelerated by the electric field between the extraction electrode and a titanium target. Finally, the deuterium ion beam bombards the titanium target, and a deuterium-deuterium fusion reaction occurs to generate neutrons. At the same time, an arc magnet and a resistor are used to suppress the secondary electrons generated by the target, so as to prevent the secondary electrons from being reversely accelerated and entering the ion source chamber. The present application has the advantages of low energy consumption, a compact structure, high plasma density, autonomous cooling, a good secondary electron suppression effect, high extraction beam intensity, and a high neutron yield.

The invention discloses a neutron source based on an FRC linear magnetic confinement nuclear fusion device, and relates to the technical field of fusion devices. The neutron source comprises a vacuum chamber for providing a vacuum environment for fusion reaction; the magnet system is arranged outside the vacuum chamber and is used for ionizing gas in the vacuum chamber and generating fusion reaction; the neutron extraction system is arranged in the fusion reaction generation area of the vacuum chamber and is used for extracting epithermal neutrons; the neutron lead-out system comprises a neutron lead-out channel, a shielding and reflecting device and a filter, the shielding and reflecting device is arranged outside the lead-out channel and used for shielding and reflecting neutrons, and the filter is arranged in the neutron lead-out channel and used for filtering fast neutrons, thermal neutrons and photons; the neutron source provided by the invention has the advantages of higher neutron yield, simple and compact structure, effectively reduced overall device volume, low construction and maintenance cost and small nuclear safety prevention and control pressure, and can be used in various fields of medical treatment, scientific research, military industry and the like.

The invention discloses a neutron target with low thermal stress, and relates to the technical field of neutron targets, the neutron target comprises a first target layer and a second target layer, and the non-bombardment surface of the first target layer is attached and welded to one side surface of the second target layer; the first target layer is divided into a central target piece and a plurality of sector ring target pieces distributed around the central target piece by a groove, the depth of the groove extends from the first target layer to the second target layer, the groove bottom of the groove is located on the second target layer, and the material ductility of the second target layer is larger than that of the first target layer. According to the neutron target, the technical problem that the neutron yield is limited due to the thermal stress of the neutron target in the prior art is solved, and the neutron target with low thermal stress and high neutron yield is provided.

The present invention discloses a deuterium beam pulse modulation device and a pulse neutron generator, including a fixing bolt and a mounting seat, wherein a sliding cavity is provided inside the mounting seat, a sliding hole is provided at one end of the mounting seat, one end of the fixing bolt passes through the sliding hole and is located in the sliding cavity and fixedly connected to a circular plate, the outer wall of the mounting seat is sleeved with a coil fixing cylinder, the fixing cylinder does not contact the mounting seat, a gap channel is provided between the coil fixing cylinder and the mounting seat, the inner wall of the coil fixing cylinder is located in the gap channel and fixedly connected to a pulse magnetic field modulation coil, the coil fixing cylinder is fixedly connected to an anode sleeve near the edge of one end of the fixing bolt, and the end of the coil fixing cylinder is fixedly connected to a metal electrode ring. The present invention has a compact structure and a simple power supply method, can effectively improve the deuterium ion yield and proportion, and can also widen the beam pulse waveform to obtain a better flat-top pulse waveform, providing effective guarantee for subsequent use in a pulse neutron generator device to obtain a small beam spot and a high neutron yield.

The present invention relates to a method for increasing the neutron source yield of a proton accelerator, comprising the following steps: constructing a double-layer target chamber, including a tritium gas target chamber and a helium gas target chamber, wherein a lithium target is fixedly installed in the helium gas target chamber; filling the tritium gas target chamber with tritium gas until a set tritium gas target chamber pressure is reached; filling the helium gas target chamber with helium gas until a set helium gas target chamber pressure is reached; and injecting protons into the double-layer target chamber through a proton injection main pipe. The method provided by the present invention can increase the neutron yield below 1 MeV obtained by the accelerator neutron source by more than 95% compared to traditional methods, effectively utilizing beam time, increasing neutron flux, reducing the proportion of environmental background, and improving experimental results. The method provided by the present invention can eliminate interference from neutrons with energies above 1 MeV, which can reduce interference from other reactions for nuclear physics experimental measurements. For boron neutron therapy accelerators, the low neutron energy makes it easy to moderate and shield, which can reduce additional shielding measures.

The application discloses a kind of uranium mine logging instrument based on ultrashort pulse neutron and working method thereof, it is related to uranium mine exploration well logging field;Logging instrument includes control communication nipple arranged in sequence along its axial direction, ultrashort pulse neutron generator for emitting fast neutron pulse with pulse width less than 1 microsecond to formation, shielding body, dual thermal neutron detection assembly for detecting thermal neutron and superhot neutron on spatially consistent measurement point, gamma detector for detecting non-elastic scattering gamma ray and capture gamma ray emitted by formation element, and fast neutron detector and multichannel synchronization and high-speed acquisition circuit for detecting and outputting source intensity monitoring signal of fast neutron pulse in real time;The logging instrument of the application emits ultrashort fast neutron pulse and detects neutron yield in real time, combines to obtain neutron time spectrum and multi-dimensional information of gamma energy spectrum with accurate time stamp, carries out high-precision, anti-interference inversion to formation uranium content, and efficiently and accurately obtains formation information.

The invention belongs to the technical field of neutron sources, and particularly relates to a high-voltage multiplication controllable isotope neutron source. According to the controllable neutron source, the characteristic that an alpha particle band is extremely easy to absorb and block is utilized, blocking and penetrating of alpha particles released by an alpha radioactive source are controlled by optimizing the hole opening design and the rotating speed of a chopper (neutron switch), the controllable neutron source in three continuous, closed and pulse emission modes is established, and the controllable neutron source is controlled by increasing negative high voltage at the two ends of the alpha radioactive source and the two ends of a Be target. The characteristic that the alpha particles are positively charged is utilized, acceleration is formed, the efficiency that the alpha particles penetrate through the chopper is improved, the Be target is bombarded at a high speed, then the neutron yield is increased, and the problem that the efficiency that the alpha particles penetrate through the chopper in vacuum due to diffusion motion is low, and consequently the neutron yield is low is solved.

The application discloses a kind of neutron tube structures of accelerating polar adjustable radial extraction penning ion source, including sleeve, the one end inside sleeve is equipped with anode cylinder, the outer embedding of the cylinder body of anode cylinder is equipped with insulator, radial extraction hole is opened in the side of anode and insulator, the outside of radial extraction hole is coaxially equipped with acceleration cylinder with insulator, copper target is equipped at the tail end of acceleration cylinder;When using, adjusting nut, lengthening or compressing corrugated expansion pipe, the distance between acceleration cylinder and discharge cavity is adjusted, then external circuit is added voltage to anode cylinder, under the joint action of electric and magnetic field, gas ionizes, generates ion, ion is extracted through radial extraction hole, at this time, acceleration cylinder applies positive high voltage, ion is accelerated and extracted, and neutron is generated by hitting copper target;The present application is more easily extracted by setting radial extraction hole and configuring corrugated expansion pipe around acceleration cylinder, improves acceleration performance, controls the area of ion beam hitting copper target, improves copper target utilization rate, and improves neutron yield.

The application provides a neutron tube testing device and a testing method. The neutron tube testing device comprises a vacuum mechanism, an atmosphere control mechanism, a feeding mechanism and a supporting mechanism, the vacuum mechanism and the atmosphere control mechanism are both installed on the supporting mechanism, the feeding mechanism is installed in the vacuum mechanism, and the atmosphere control mechanism is connected with the vacuum mechanism. The device is used for testing the service life of a neutron target and the neutron yield of the neutron target, and checking the qualified rate of the neutron target in the production link. The neutron target is tested before the neutron tube is sealed, so that the whole neutron tube is prevented from being scrapped, material waste is avoided, and the research and development testing time is prevented from being delayed. The device is used for researching the influence of different film thicknesses on the neutron yield of the neutron target, the influence of different magnetic field strengths, different extraction hole structures and other factors on the ion source, and the influence of different structure ion sources or different structure accelerating electrodes on the neutron yield, so that the economic cost and time cost of the sealed neutron tube are reduced.

The invention relates to the technical field of design of conversion bodies for laser beam target neutron sources, and provides a conversion body for a laser beam target neutron source and an optimization design method of the conversion body. The conversion body for the laser beam target neutron source comprises a front plate, a surrounding side plate and a rear plate, the front plate, the surrounding side plate and the rear plate define a sealed inner cavity, and the sealed inner cavity is filled with embedded objects to form a wrapping type cubic structure; at least one of the front plate, the peripheral side plates and the rear plate is made of materials which are stable in chemical property, good in mechanical property and easy to form. And the embedded object is formed by filling a substance with excellent neutron generation capability. The neutron generation capability of beryllium is not affected while the beryllium material is wrapped by designing the wrapping layer, the stability of the neutron yield is ensured while the experiment safety is provided, and the technical problem that an existing conversion body limits popularization of a laser beam target neutron source in high-precision application is solved.

The invention discloses a neutron beam shaping system for a BNCT, and relates to the technical field of neutron regulation and control, the system comprises a moderation module which is used for decelerating high-energy fast neutrons from a target material into surface thermal neutrons or thermal neutrons, the moderation module is made of an aluminum fluoride material, and a value adding module which is arranged between the target material and the moderation module and is used for adding the surface thermal neutrons or the thermal neutrons into the surface thermal neutrons or the thermal neutrons. The value-added module is used for increasing the neutron yield, the value-added module is made of a metal molybdenum material with the thickness of 9 cm, the gamma absorption module is used for absorbing gamma rays generated in the moderation process, and the gamma absorption module is made of a bismuth material with the thickness of 2.5 cm; compared with an existing BSA system, the neutron beam shaping system for the BNCT is more efficient and reliable in the aspects of neutron yield, ray purification capacity and dose space control, and the dose precision and biological selectivity of BNCT treatment can be improved.

The invention discloses a neutron target system design method and a neutron target system designed by adopting the design method.The neutron target system design method comprises the steps that a solid target and a liquid target are arranged at the same time, and the liquid target is arranged on the side, away from the coming direction of particle beams, of the solid target; obtaining a neutron yield standard value and a neutron yield target value; if the neutron yield standard value is greater than or equal to the neutron yield target value, respectively configuring the thickness of the solid target and the liquid target according to the neutron yield target value; and if the neutron yield standard value is smaller than the neutron yield target value, making a difference between the neutron yield target value and the neutron yield standard value to obtain a neutron yield difference value, and configuring the thickness of the liquid target according to the neutron yield difference value. The technical problems that in the BNCT field, high neutron yield is obtained, particle beam parameters (beam energy and / or beam intensity) correspondingly need to be improved, an accelerator system is complex, the manufacturing cost is high, generated radioactivity is large, and the radioactive waste disposal cost is high are solved.

This invention relates to the field of ion source technology and discloses a transmission system for a small negative high-voltage neutron source. The transmission system includes a transmission tube, a plasma electrode, an extraction electrode, a Helmholtz coil, and an aperture. The transmission tube has a vacuum channel, and the plasma electrode and the extraction electrode are located inside the vacuum channel, downstream of the plasma electrode in the beam transmission direction. The Helmholtz coil is located outside the transmission tube. This transmission system can overcome the technical problem of how to achieve 100 mA beam transmission and beam homogenization within a limited structural size for a small negative high-voltage neutron source. The Helmholtz coil and aperture can effectively suppress the space charge effect of the ion source, enhance the beam transmission efficiency, and improve beam homogenization. Simultaneously, it can reduce the target surface heat load, improve neutron yield, and increase the target's service safety and lifespan.