544results about "Magnetic resonance accelerators" patented technology

The invention relates to the field of medical equipment, and provides a compact multi-chamber proton treatment system based on a shared beam line, and the system comprises a fixed beam transmission line which is used for guiding the movement direction of a proton beam into a vertical direction; the rotating beam transmission line is used for guiding the movement direction of the proton beam into the horizontal direction; one end of the fixed beam transmission line is connected with the proton cyclotron, the other end of the fixed beam transmission line is connected with one end of the rotary beam transmission line, and the other end of the rotary beam transmission line is in butt joint with a plurality of treatment rooms; the rotating beam transmission line rotates around a central axis extending in the vertical direction. According to the invention, the proton beam can be safely, efficiently and accurately transmitted to each treatment room, and a fixed beam transmission system and a rotating rack do not need to be independently arranged for each treatment room, so that the beam control assembly and the system occupied area of the multi-room particle treatment device are minimized, and the number of treated patients can be remarkably increased.

The invention relates to the technical field of medical cyclotrons, in particular to a medical cyclotron magnetic field intensity adjusting method based on temperature compensation, and the method comprises the following steps: in the process of adjusting the magnetic field intensity of a main magnet based on temperature information, obtaining a temperature variation threshold: collecting the temperature on the surface of the main magnet in real time; determining a temperature difference coefficient, a temperature anomalous coefficient, a temperature abnormal coefficient and a trend approximate value of each acquisition moment; comprehensively analyzing the temperature values acquired by all the sensors, and determining the temperature difference degree and difference factor of each sensor at each acquisition moment; determining the avoiding adjustment value of each sensor at each acquisition moment; and acquiring a temperature variation threshold value at each acquisition moment. The invention aims to solve the problem that the magnetic field intensity of the cyclotron cannot be adjusted according to the actual environment temperature, so that the beam stability and the beam extraction efficiency in the operation process of the medical cyclotron are improved.

The invention provides an ultra-short beam homogenization transmission line system and method based on a four-eight-pole composite magnet. The system comprises the four-eight-pole composite magnet, a system, a linear beam homogenization structure, a bent beam homogenization structure and secondary iron used for a beam homogenization transmission line. The system further comprises an ultra-short linear beam homogenization transport line, an ultra-short bent beam homogenization transport line, an ultra-short linear bent composite beam homogenization transport line and an ultra-short symmetrical bent beam homogenization transport line based on the homogenization structure and / or the dipolar iron. The method comprises an exciting current debugging method based on the four-pole and eight-pole composite iron and a linear type and bending type beam debugging method. According to the invention, the problem that the maximum enveloping part on the transmission line is occupied and the effect of octopole iron cannot be fully exerted is solved; the problems that the beam envelope of the position where the octopole iron is located is small, and the requirement for the field intensity of the octopole magnet is high are solved. The problem that the civil engineering shielded around the transmission line is more expensive because the transmission line is too long is solved.

The invention discloses a single-coil winding type four-eight-pole composite iron system for beam homogenization. The composite iron system comprises a composite magnet current control device, a composite magnet main power supply and four-pole / eight-pole composite iron, the quadrupole / octupole composite iron has eight pole heads, and only one type of excitation coil is wound on each pole head; the current value of the A-type excitation coil is an absolute value of a quadrupole magnetic field excitation current value plus an octupole magnetic field excitation current value; the current value of the B-type excitation coil is an absolute value obtained by subtracting an octupole magnetic field excitation current value from a quadrupole magnetic field excitation current value; the quadrupole / octupole composite iron is used for simultaneously generating a dominant quadrupole magnetic field and an octupole magnetic field, so that the effects of quadrupole iron and octupole iron can be simultaneously realized by only installing one transmission element; the excitation coil structure of the quadrupole / octupole composite iron composite magnet is improved, and only one excitation coil is wound on each pole head, so that the size of the coil structure can be reduced, and the construction cost is reduced.

The invention discloses a method for dynamically adjusting the frequency of a resonant cavity of a cyclotron and a tuning circuit, which are applied to the field of cyclotrons and solve the problem that when the frequency of the resonant cavity of the cyclotron is adjusted by judging the magnitude of reflection power, due to the fact that the reflection power can change in multiple stages in a single macro pulse period, the frequency of the resonant cavity of the cyclotron is adjusted. And an accurate numerical value is difficult to obtain through a simple amplitude sampling circuit. According to the invention, through determining the stable resonance time period of the resonant cavity, the phase difference between the incident power signal and the reflection power signal is sampled in the corresponding stable resonance time period of the resonant cavity, and the change value of the phase difference between the incident power signal and the reflection power signal is dynamically compared. According to the conversion relation between the phase difference change value and the frequency change value, the resonant cavity frequency change value is obtained through conversion, then the resonant cavity tuning device is adjusted to enable the resonant cavity frequency to be consistent with the frequency of the incident power signal all the time, and the dynamic tuning method of the resonant cavity is achieved.

The invention discloses a high-gradient particle accelerator and a cancer treatment device, and the high-gradient particle accelerator comprises an ion source which is used for generating and leading out a particle beam for treatment; an inlet of the superconducting radio frequency quadrupole field accelerator is connected with the ion source through a low-energy transmission line, and the superconducting radio frequency quadrupole field accelerator is used for pre-accelerating the particle beam generated by the ion source to obtain a low-energy particle beam; an inlet of the superconducting linear acceleration section is connected with an outlet of the superconducting radio frequency quadrupole field accelerator through a first beam transport line, and the superconducting linear acceleration section is used for accelerating the low-energy particle beam led out by the superconducting radio frequency quadrupole field accelerator again to obtain an intermediate-energy particle beam; and an inlet of the annular accelerator is connected with an outlet of the superconducting linear acceleration section through a second beam transport line, and the annular accelerator is used for carrying out ultimate acceleration on the intermediate-energy particle beam led out by the superconducting linear acceleration section so as to obtain a high-energy particle beam with target energy. The scheme that the superconducting linear accelerator is combined with the annular accelerator is adopted, so that particle beam energy is accelerated to target energy meeting cancer treatment.

The invention relates to the technical field of cyclotron current regulation, in particular to a medical cyclotron polymorphic tuning method and system, and the method comprises the steps: dividing change periods according to the similarity of the local change trend of high-frequency cavity pressure, and obtaining the change periods; according to the fluctuation amplitude of the cavity pressure rising section, the fluctuation frequency of the cavity pressure falling section and the frequency domain information difference between each change period and the adjacent period in each change period, the resonant frequency interference degree is obtained; obtaining a phase difference oscillation coefficient according to the stability degree of the phase difference change and the resonance frequency interference degree in each change period; obtaining a stable matching index according to the concentration condition of the value distribution of the phase difference oscillation coefficients of all the change periods; and calculating the excitation current variable quantity of the next change period according to the resonant frequency variable quantity of the current change period and the stable matching index. The excitation current can be adjusted in time to control the magnetic field intensity, and the tuning efficiency of the cyclotron is improved.

The invention discloses a conduction cooling type superconducting isochronous cyclotron, and belongs to the technical field of superconducting isochronous cyclotrons. Comprising an accelerator main support, the accelerator main support is integrally of a base frame structure composed of a plurality of vertical supports, vertically-arranged hydraulic lifting systems are further fixedly installed on the side walls of each set of vertical supports, and a first magnet yoke is fixedly installed at the top of the accelerator main support; a refrigerating machine direct conduction cooling technology is adopted, a traditional liquid helium soaking cooling system is replaced, and the problem that a superconducting cyclotron depends on a complex liquid helium refrigeration unit and is redundant in structure is solved. While the magnetic field intensity is maintained, heavy parts such as a liquid helium pool, a recondenser and a multi-layer heat insulation pipeline are completely abandoned, so that the system height and the sealing complexity are remarkably reduced, and high operation and maintenance cost caused by dependence of liquid helium resources is also avoided.

The invention discloses a compact multipurpose proton beam system, belongs to the field of radiotherapy, and solves the problem that a treatment terminal of an existing proton beam system is single in type and not compact enough. The superconducting isochronous cyclotron system is connected to the two-way selection system through the beam adjusting system, the two-way selection system comprises a two-way dipole magnet and two branch selection systems, and the two branch selection systems are connected to the rear end of the two-way dipole magnet in parallel. The system also comprises a beam transport system, and the beam transport system is composed of a first treatment terminal section, a second treatment terminal section and a third treatment terminal section. One branch selection system is connected to the fixed experiment beam transport system through the first treatment terminal section, the other branch selection system is connected to the fixed pen-shaped beam transport system through the second treatment terminal section, the third treatment terminal section is a branch of the second treatment terminal section, and the third treatment terminal section is connected to the rotary beam transport system. According to the invention, the beam irradiation of the multi-type and multi-purpose treatment terminal is realized by utilizing the design of a bidirectional selection system.

A magnetic orbital angular momentum beam accelerator will accelerate charged particles, electrons or ions, from rest in zero or low magnetic field into a high magnetic field regions with high kinetic energies in the form of magnetic orbital angular momentum. For example, a beam injector that accelerates electrons or ions into 1T magnetic fields with tens of keV kinetic energies transverse to the magnetic fields can be used to heat magnetically confined plasmas, to inject an initial energetic plasma component with high magnetic orbital angular momentum and to produce highly transverse particle momenta to the magnetic field for electron or ion beam lithography.

The invention discloses an ion source automatic beam adjusting method, a radiotherapy system and related equipment, and relates to the technical field of radiotherapy, and the method comprises the steps: monitoring and adjusting a plurality of control parameters in real time, and obtaining an optimal control parameter combination; under the optimal control parameter combination, the variable quantity of each control parameter before and after adjustment and the performance change of the proton beam are obtained; performing a pulse width charge test according to the variation of each parameter before and after adjustment and the performance change of the proton beam; obtaining an optimal adjustment parameter and an adjustment amount through a pulse width charge test result; and through the optimal adjustment parameter and adjustment amount, automatic beam adjustment is realized, stable and efficient acceleration of the proton beam in the synchrocyclotron system is realized, and the stability and consistency of the proton beam are ensured.

A superconducting proton cyclotron (100). The superconducting proton cyclotron (100) comprises a main cyclotron system (10), a cyclotron auxiliary system (20) and a cyclotron control system (30). The main cyclotron system (10) comprises an ion source (11), a central region (12), a superconducting magnet system (13), a radio frequency system (14) and a lead-out region (15). The ion source (11) is used for generating a proton beam; the central region (12) is used for leading out the proton beam of the ion source (11) and performing beam focusing inside the central region (12); the radio frequency system (14) leads out and accelerates the beam of the central region (12); a static magnetic field generated by the superconducting magnet system (13) can constrain the proton beam and accelerate same to target energy; the lead-out region (15) can lead out the proton beam.

The invention discloses an internal-cooling-based high-frequency coupling window for a high-power cyclotron. The internal-cooling-based high-frequency coupling window is characterized in that an air knife structure is arranged at the atmosphere end of the internal-cooling-based high-frequency coupling window; two groups of conductor choke units with different lengths are arranged on two sides of a ceramic chip of the high-frequency coupling window based on internal cooling, and the two groups of conductor choke units with different lengths are equivalent to two groups of inductors and are used for forming a double-filter circuit of the high-frequency coupling window; a ceramic coating film is arranged on one side of the ceramic sheet of the high-frequency coupling window; according to the air knife structure, more heat on the surface of the ceramic chip is taken away through compressed air; on one hand, the filter unit and the conductor choke unit form a filter circuit of a high-frequency coupling window atmosphere end; according to the invention, the air knife structure is ingeniously utilized, and enhanced cooling is carried out on the ceramic wafer of the coupling window structure; the inductance value of the coupling window is adjusted by using the conductor choke unit, the standing-wave ratio coefficient of the coupling window is reduced, the surface temperature of the ceramic chip is reduced, and the risk of explosion of the coupling window is reduced.

The invention discloses a radiotherapy device and an automatic search system and method for the maximum current intensity of an accelerator. The system comprises: a cyclotron, a first driving component connected to the cyclotron and a first ion source respectively, and driving the first ion source to move away from a second ion source according to a preset step length; a second driving component connected to the cyclotron and the second ion source respectively, and driving the second ion source to move away from the first ion source according to a preset step length; a recording module connected to the first and second driving components, recording all first positions and second positions of the first and second ion sources, and all position combinations corresponding to each first position and the second position; a debugging module controlling the cyclotron to emit a beam under each position combination, and introducing, accelerating and extracting protons generated by the first and second ion sources; a storage module, acquiring and storing the beam intensity corresponding to each position combination to form a data set; and a search module searching for the maximum beam intensity from the data set to ensure a better radiotherapy effect.

The invention discloses an air suction thin-wall part and a preparation method thereof, a vacuum chamber assembly and a vacuum regulation and control method, the air suction thin-wall part is used for being detachably installed in a vacuum chamber of a cyclotron, and the air suction thin-wall part can be activated and adsorb air in a vacuum chamber body; the air suction thin-wall part is used for surrounding the position close to the inner side wall of the vacuum chamber body. The air suction thin-wall part is provided with a plurality of open holes, and the surface area of the inner wall of each open hole is at least two times larger than the area of the cross section of the corresponding open hole. The technical problems that in the prior art, due to the fact that a compact cyclotron is small in size and small in available space, it is difficult to maintain the long-time high-vacuum state in the vacuum chamber by installing a plurality of low-temperature cold plates or additionally arranging a plurality of vacuum pumps are solved. The auxiliary device assists an existing vacuum pump to jointly maintain a long-time high-vacuum state in the vacuum chamber, so that the requirement for the pumping speed of the vacuum pump is lowered, and the pumping speed of an existing common vacuum pump can meet the requirement.

The double-sided cooling capsule target chamber comprises a capsule target piece assembly, a bearing assembly, a target chamber head assembly and a target chamber tail assembly, and the capsule target piece assembly is circular; a groove part and a channel communicated with the groove part are formed in the bearing assembly, and a capsule target piece assembly is arranged in the groove part; a helium cooling channel and a water cooling channel are respectively arranged in the bearing component corresponding to the front surface and the back surface of the capsule target sheet component; the target chamber head assembly is fixed at one end of the bearing assembly, and the target chamber head assembly is provided with a leading-in part for leading an accelerator particle beam into the channel; the target chamber tail assembly is fixed to the other end of the bearing assembly. The double-face cooling effect of copper supporting face water cooling and aluminum supporting face gas cooling can be achieved on the capsule target piece assembly, and the use feasibility of target pieces made of different heat conduction performance materials is improved; the irradiation efficiency is improved, the manufacturing cost is reduced, and conveying and cooling are facilitated; and meanwhile, the treatment capacity of dissolution and separation of the irradiated target sheet can be reduced, and the post-treatment cost is reduced.

A disturbance magnetic field region provided in an outer peripheral portion of a main magnetic field region of an accelerator has a peeler region in which a strength of a magnetic field decreases toward an outside, a regenerator region in which the strength of the magnetic field increases toward the outside, and a substantially flat region in which the strength of the magnetic field is larger than the strength of the magnetic field of the peeler region and smaller than the strength of the magnetic field of the regenerator region.

An acceleration voltage measurement circuit outputs an acceleration voltage signal Vacc as a measurement signal in which an acceleration radiofrequency voltage excited in the accelerating cavity is measured. A low power radiofrequency control system inputs, to the accelerating cavity, as radiofrequency power, control radiofrequency power at a constant frequency included in the range of the resonance frequency of the accelerating cavity. When the phase difference between the acceleration voltage signal Vacc and the control radiofrequency power becomes within the predetermined value, the low power radiofrequency control system inputs, to the accelerating cavity, as radiofrequency power by feedback control, the acceleration radiofrequency power synchronized with the acceleration frequency that is the frequency of the acceleration voltage signal Vacc, and thereafter, when the acceleration frequency reaches an output frequency Fext, stops the input of the acceleration radiofrequency power to the accelerating cavity.

There is provided a circular accelerator that accelerates a beam of charged particles circulating in a magnetic field such that a closed orbit for each energy of the beam is eccentric. The circular accelerator includes a beam extraction port for extracting beams of different energies from the closed orbit, a first bending magnet and a second bending magnet that bend the beam extracted from the beam extraction port, and a control unit that controls magnetic field strengths of the first bending magnet and the second bending magnet in accordance with the energy of the extracted beam. When the energy of the extracted beam is a designed maximum energy of the circular accelerator, the control unit excites both the first bending magnet and the second bending magnet to bend the beam.

The invention discloses a radiation-resistant all-digital high-frequency low-level control system which is characterized in that the system can be arranged on an accelerator site with strong radiation and is used for solving the problem that signals are interfered due to the fact that the signal transmission distance is too long. According to the system, the functions of all peripheral chips which cannot work normally due to strong radiation on the accelerator site are included in the radiation-resistant FPGA chip, and the functions of all the external chips and the original functions of the radiation-resistant FPGA chip are achieved through the radiation-resistant FPGA chip. The system is realized by using a single radiation-resistant FPGA chip, a high-frequency digital control algorithm is realized through firmware program design of the radiation-resistant FPGA chip, the control function of a high-frequency low-level control system is met, and the radiation-resistant problem of the whole system is directly solved. The system can be placed on the site of an accelerator, breaks through the limitation that a transmission cable needs to penetrate through a wall, is closer to a controlled object, and does not need a radio frequency cable to penetrate through a pipeline in the wall.

The invention relates to the technical field of superconducting cyclotrons, and discloses a spiral resonant cavity for a superconducting cyclotron, which comprises an upper resonant cavity body and a lower resonant cavity body, and the upper resonant cavity body is positioned right above the lower resonant cavity body; through distributed waterway design and structural optimization, the cooling system can effectively process heat generated in the accelerator; efficient heat dissipation of the system is ensured through design means such as a multi-directional cooling channel, an oxygen-free copper brazing pipeline and a double-path independent cooling pipe, excessive accumulation in a high-temperature area is avoided, and meanwhile the stability of equipment can be kept in long-time operation; the structure of the single inner rod is convenient for voltage distribution adjustment, the structure is simple and compact, and the processing complexity and the manufacturing cost are greatly reduced; a core component solution with high reliability and low operation and maintenance cost is provided for the superconducting cyclotron, and application efficiency upgrading in the fields of medical treatment, scientific research and the like is promoted.

The invention discloses an ultrashort bending type beam homogenization transmission line. The ultrashort bending type beam homogenization transmission line is characterized in that the transmission line is an ultrashort bending type high-current homogenization transmission line comprising two pieces of four-eight-level composite iron and one piece of second-level iron; the ultra-short bending type high-current homogenized transmission line is an ultra-short bending type high-current homogenized transmission line A which is arranged along a beam current direction; or the ultra-short bending type high-current homogenization transmission line B is arranged along the beam direction; the ultra-short bending type high-current homogenization transmission line A is sequentially provided with an accelerator leading-out port, a beam matching mechanism, fourth and eight-stage composite iron 1, second-stage iron, fourth and eight-stage composite iron 2, a beam matching and homogenization effect observation mechanism 1 and a terminal 1 along the beam leading-out direction; the tetra-octupole composite iron of the beam line can simultaneously realize focusing and homogenization effects on beam envelope, the composite iron is installed on a beam transmission line, the number of transmission elements can be reduced, the length of the transmission line is shortened, and the construction cost of the beam transmission line is reduced.

The invention relates to the technical field of axial focusing enhancement of a cyclotron, and provides an axial focusing enhancement method and system for a medical cyclotron, and the method comprises the steps: collecting vibration data, a beam intensity value, temperature data, the positions of all particles in a particle beam, the average magnetic field intensity, the magnetic field intensity difference, and the current; the divergence angle and energy of the particle beam are measured; determining an axial focusing effect evaluation value at the current sampling moment; determining the particle beam stability at the current sampling moment, and determining the magnetic field uniformity at the current sampling moment by combining the average magnetic field intensity and the magnetic field intensity difference at the current sampling moment; and the axial focusing effect evaluation value, the average magnetic field intensity and the current at the current sampling moment are combined to realize the axial focusing enhancement of the medical cyclotron. According to the invention, the focusing precision of axial focusing enhancement of the medical cyclotron and the stability of the focusing effect can be improved.

The invention discloses a dual-mode precise regulation and control method and device for a proton treatment system, and relates to the technical field of proton treatment, and the device comprises a superconducting cyclotron, a beam transmission module, a treatment head module which comprises a first ionization chamber, a second ionization chamber, a range regulator, a multi-leaf grating and scanning iron, a treatment chair and a control module, the control module is used for receiving and analyzing a treatment plan and controlling the working states of the superconducting cyclotron, the beam transmission module, the treatment head module and the treatment chair in different working modes according to the treatment plan; the working mode comprises a first working mode and a second working mode, and the radiation dose of a proton beam required by the second working mode is far greater than the radiation dose of the proton beam required by the first working mode. The dual-mode precise regulation and control device can support a conventional working mode and also can support a flash therapy working mode, and different working modes can be switched to realize a treatment plan.

The invention discloses a quadrupole / octupole composite iron system for beam homogenization. The composite iron system comprises a composite magnet current control device, a composite magnet main power supply and quadrupole / octupole composite iron, the composite magnet current control device is used for controlling a composite magnet main power supply to output quadrupole field coil current and octupole field coil current of quadrupole / octupole composite iron. The quadrupole / octupole composite iron is used for simultaneously generating a dominant quadrupole magnetic field and an octupole magnetic field, so that the effects of quadrupole iron and octupole iron can be simultaneously realized by only installing one transmission element; according to the invention, a quadrupole magnetic field and an octupole magnetic field are generated in the aperture of the composite iron, focusing and homogenization of beam envelope are realized at the same time, the number of transmission elements can be reduced, the length of a transmission line can be shortened, and the construction cost of the beam transport line is reduced. The problem that traditional quadrupole iron and octupole iron cannot be simultaneously installed at the maximum beam envelope position due to the space problem and cannot play a great role of a magnet is solved.

A beam equipment controlling method is provided. The method includes: proton beam regulatory steps, including: generating a first proton beam after confirming that the generating conditions are met, and marking the proton beam regulatory steps as completed after confirming that the first proton beam meets the specifications; neutron beam regulatory steps, including: generating a first neutron beam after confirming that the proton beam regulatory steps are completed and the generating conditions are met, confirming that the first neutron beam meets specifications, and marking the neutron beam regulatory steps as completed after turning off the cyclotron system; and treatment regulatory steps, including: generating a second neutron beam after confirming that the neutron beam regulatory steps are completed and the treatment-beam generating conditions are met, confirming that the second neutron beam meets treatment needs; and marking the treatment regulatory steps as completed after turning off the cyclotron system.

The present invention relates to a synchrotron fast-response magnetic alloy high-frequency system, comprising: a control circuit for generating a waveform signal; a full-solid-state power source for receiving the waveform signal and performing power synthesis to generate a power signal; an impedance phase compensator for realizing impedance rise and fall and phase compensation; an impedance transformer for realizing impedance transformation to achieve impedance matching between the full-solid-state power source and the magnetic alloy-loaded resonant cavity; a magnetic alloy-loaded resonant cavity for receiving the power signal and generating a radio frequency signal to operate on the heavy ion beam; and a sampling circuit for sampling the radio frequency signal and feeding it back to the control circuit. The synchrotron fast-response magnetic alloy high-frequency system provided by the technical solution of the present invention has performance indicators of low frequency, high bandwidth, fast rising of voltage signal and response, and can output single-sine and half-sine waveforms, realizing the functions of capturing, accelerating and Barrier Bucket bunch accumulation for various heavy ion beams.

The invention discloses a novel electronic gun for a cyclotron wave protector, and relates to the technical field of vacuum electronic devices. The electron gun comprises a cathode assembly, an anode assembly, a supporting assembly and a permanent magnet system. Wherein the cathode assembly adopts a planar cold cathode structure; the anode assembly comprises an anode main body and an electron beam channel in the anode main body; the cathode and the anode are fixedly connected through a supporting assembly; the permanent magnet system provides a uniform magnetic field. The cold cathode is adopted to replace a traditional hot cathode to generate high-quality strip-shaped electron beams, and the device has the advantages of being simple in structure, easy to integrate, rapid to start, long-acting, reliable, low in consumption and energy-saving.

The invention relates to a low-energy type cyclotron and a solid target device used for the low-energy type cyclotron, and the solid target device comprises a target material installation part which is used for installing a target material and comprises a first end and a second end which are oppositely arranged in the first direction; the first cooling piece is arranged at the first end of the target material mounting piece, a first cooling cavity is formed in the first cooling piece, and a gas cooling medium circulates in the first cooling cavity; and the second cooling piece is arranged at the second end of the target material mounting piece, a second cooling cavity is formed in the first cooling piece, and the second cooling cavity is used for circulating a liquid cooling medium. The cyclotron is simple in structure and low in refitting cost, can be additionally arranged on the basis of an original accelerator system, does not need to be reformed, and greatly reduces the use cost; by arranging the first cooling piece and the second cooling piece which are separated, air cooling and water cooling are physically isolated, no mixed loop exists, starting is conducted as needed through an independent control system, the cooling efficiency is greatly improved, and the cooling device is more suitable for the low-energy cyclotron.

A particle acceleration and extraction system includes a cyclotron having a stripping assembly and a target. The cyclotron includes an acceleration chamber and is operable to generate a magnetic field and an electric field in the acceleration chamber such that charged particles in the acceleration chamber are accelerated along a spiral path extending outward and at increasing energies from an initial energy E1 to a final energy E2, E2 being greater than E1. The target defines a target location outside of the acceleration chamber. The stripping assembly is positioned in the acceleration chamber and is operable to extract a charge from the charged particles at an intermediate location of the outward spiral path whereby the post-stripping assembly particles are directed towards the target location. The charged particles have an intermediate energy E3 at the intermediate location that is between E1 and E2.