Disclosure of Invention
The first object of the present invention is to provide a low-energy heavy ion accelerator, which realizes corresponding step-by-step loading for each motion stage of ions, so that an ion beam is always in an acceleration phase, and further, the requirements of higher acceleration efficiency and beam transmission efficiency are satisfied;
the second purpose of the invention is to provide a low-energy heavy ion acceleration method, which is to load voltage to each stage of acceleration cavity according to time sequence so as to form an electric field step by step, so that ions just entering the field can be directly accelerated, and finally the purposes of high efficiency, full ions and high beam energy of heavy ions are achieved.
Embodiments of the present invention are implemented as follows:
the low-energy heavy ion accelerator comprises a pulse power source with a time sequence control function and a plurality of continuously arranged accelerating units, wherein the accelerating units are provided with accelerating cavities, and all the accelerating cavities are communicated with each other and form an accelerating transmission channel of ions; along the advancing direction of the accelerating transmission channel, the pulse power source can control all accelerating units to be loaded with voltage step by step according to the corresponding time sequence and form an electric field in the corresponding accelerating cavity, so that ions which just move into the accelerating cavity forming the electric field are accelerated, and the step-by-step acceleration of the ions in the accelerating transmission channel is realized. I.e. the ions which just move into the accelerating cavity forming the accelerating electric field are accelerated under the action of the accelerating electric field, in this way the aim of stepwise acceleration of the ions in the accelerating transport channel is finally achieved.
Optionally, all the accelerating units are serially connected in a step-by-step manner, so that the accelerating transmission channels are in a linear layout. The accelerating cavity adopts columnar cavities, and all the columnar cavities form an accelerating section, namely an accelerating transmission channel; the axis of the accelerating section is not provided with a field-free drift tube, pulse voltage is adopted for power supply, and the accelerating units are connected in series step by step, so that the accelerating section has higher average accelerating gradient which can reach 10MV/m order, and the whole ion accelerator is compact and small.
Optionally, the accelerating unit includes two conductors and an insulator disposed between the two conductors, an accelerating cavity is formed in the insulator, the conductors each have a conductive end connected to the accelerating cavity, and the pulse power source is connected with the two conductors as positive and negative electrodes through the high-voltage feed cable, so that the two conductors can form an electric field in the same direction as the travelling direction in the accelerating cavity.
Optionally, in the adjacent accelerating cavities, conductors close to each other are arranged in series, and a radial isolation magnetic core is sleeved on the high-voltage feed cable; the end of the acceleration transmission channel is provided with an axial isolation magnetic core.
Optionally, adjacent conductors in the accelerating cavities are integrally disposed.
Optionally, the conductor and the insulator are both in a coaxial annular structure, an accelerating cavity is formed in an inner hole of the insulator, and a matching resistance ring is sleeved outside the insulator.
Optionally, an insulating medium layer is arranged at the matching resistor ring, so that the matching resistor ring and all the accelerating units are in an insulating protection state, and particularly the outside of the accelerating units are in an insulating medium.
Optionally, the insulating medium is an insulating gas or insulating oil liquid.
On the other hand, the low-energy heavy ion acceleration method adopts the low-energy heavy ion accelerator, and the specific acceleration steps are as follows:
and controlling the pulse power source to load voltage step by step on all the accelerating units according to a certain time sequence, and forming an electric field in the accelerating cavity corresponding to the accelerating unit so as to accelerate ions which just move into the accelerating cavity forming the electric field.
Optionally, the timing control of the pulsed power source refers to: and predicting the position and time of the ion beam according to the energy and the type of the ion beam to be accelerated and the structural length of the whole acceleration transmission channel, so as to calculate when the ion beam reaches the next acceleration cavity, and finally realizing that the pulse power source controls the loading voltage according to a certain time sequence.
The embodiment of the invention has the beneficial effects that:
according to the accelerator provided by the embodiment of the invention, through setting up and constructing continuous accelerating units, each accelerating unit can carry out voltage loading through a pulse power source, and when voltage loading is carried out in each accelerating unit can be preset according to corresponding parameters of an ion beam, so that the accelerator can accelerate ions just entering the accelerating unit timely and effectively, and finally, the gradual acceleration of the ion beam in the whole accelerating transmission channel is realized, and compared with the existing accelerating mode, the accelerating efficiency and the beam transmission efficiency can reach higher requirements; the accelerator has the function of accelerating all ions, and the volume and weight of the accelerator are compact and light;
the acceleration method provided by the embodiment of the invention can be realized based on the accelerator, the acceleration cavity is driven step by step through a certain time sequence control, and an electric field is formed, so that ions in the acceleration cavity which just moves into the electric field are effectively accelerated step by step, wherein the preset time sequence control can be adjusted according to requirements, so that the compatibility with the charge-to-mass ratio ion acceleration process can be ensured, the voltage amplitude loaded by the pulse power source can be correspondingly adjusted, and the control foundation provided for realizing the requirements of high acceleration efficiency and high beam transmission efficiency of ions is provided.
In general, the accelerator and the accelerating method provided by the embodiment of the invention have strong compatibility to the ion types to be accelerated, and the acceleration of any ion beam can be realized by controlling the time sequence of outputting high-voltage pulses, so that the ion beam is always in an acceleration phase; and the beam energy can be adjusted by controlling the amplitude of the accelerating voltage or controlling the number of the loading power according to the actual application requirement. Therefore, the low-energy heavy ion accelerator based on the scheme is an accelerator device with strong ion compatibility, high acceleration efficiency, high average acceleration gradient, strong beam group parameter adjustment capability and very compact layout. The method can provide target ion beams with wider parameter range, more ion types and more convenient use for application researches such as ion beam analysis, low-energy nuclear physics and the like.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the present invention, it should be noted that the terms "parallel", "perpendicular", and the like do not denote that the components are required to be absolutely parallel or perpendicular, but may be slightly inclined. For example, "parallel" merely means that the directions are more parallel than "perpendicular" and does not mean that the structures must be perfectly parallel, but may be slightly tilted.
In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Examples
Referring to fig. 1 and 2, the low-energy heavy ion accelerator provided in this embodiment includes a pulse power source (not shown) with a timing control function and a plurality of accelerating units 1 disposed in series, each accelerating unit 1 has accelerating cavities 13, all accelerating cavities 13 are mutually communicated and form an accelerating transmission channel 2 of ions, that is, an accelerating transmission channel 2 can be accelerated after an ion beam 4 is generated by an ion source 3, and a dotted line in the drawing indicates a moving track of the ion beam 4 or ions. Along the travelling direction of the acceleration transmission channel 2, the pulse power source can control all the acceleration units 1 to be charged with voltage step by step according to corresponding time sequence and form an electric field 5 in the corresponding acceleration cavity 13, so that ions which just move into the acceleration cavity 13 forming the electric field 5 are accelerated, and the step-by-step acceleration of the ions in the acceleration transmission channel 2 is realized. I.e. ions which have just moved into the acceleration chamber 13 forming the (accelerating) electric field 5 are accelerated under the influence of the (accelerating) electric field 5 in such a way that the aim of stepwise acceleration of the ions in the acceleration transmission channel 2 is finally achieved.
It can be seen that the pulse power source can output pulse voltages according to a timing control circuit preset in advance, so that the electric field 5 can be formed independently in the accelerating cavities 13 of each accelerating unit 1, and the sequence in which all the accelerating cavities 13 form the electric field 5 is formed by loading step by step according to the travelling direction of the accelerating transmission channel 2, so that ions in the ion beam 4 can just enter one accelerating cavity 13 at a time, and the electric field 5 just forms and accelerates the entered ions, thereby realizing step-by-step acceleration of the ions in the accelerating transmission channel 2. Of course, the process of forming the loading electric field 5 just entering the accelerating cavity 13 for acceleration depends on the accuracy of time sequence control, and in the process of pulse synchronous acceleration, the motion model can be calculated in advance according to different charge-to-mass ratios, different initial energies and overdue of the ion beam 4, so that the high accuracy of time sequence control is achieved, and the following acceleration method will be correspondingly described, and will not be expanded in detail here.
As can be seen from the above design, the acceleration process of the ion beam 4 by the accelerator is not a superposition of pulse voltages output by all power sources, but a superposition of step-by-step energies of the accelerated ion beam 4, which is a distinct difference from the process of accelerating the ion beam 4 by the dc high-voltage accelerator. In the conventional technology, a direct current (electrostatic) accelerator is mostly used as the low-energy ion accelerator, because for low-beta ions, a direct current high-voltage acceleration is a relatively efficient, reliable and full-ion acceleration mode, which is an important reason that electrostatic accelerators are still used as injectors in some large accelerators at present. However, dc high voltage accelerators are limited by insulation and are typically bulky and heavy, such as 25URC folding tandem accelerators installed in the american oak forest national laboratory, steel drums with diameters of about 10m, heights of about 30m, and weights up to 400t; in another example, the plasma research device DCX-2 in the United states uses a 700kv voltage-multiplying accelerator as a hydrogen ion injector, the direct current load capacity of the hydrogen ion injector reaches 1A, and the use safety distance of the hydrogen ion injector is beyond a few meters in consideration of personal safety. Therefore, the limitation of the receptor volume of the conventional direct current high voltage accelerator leads to limited application, and the direct current high voltage accelerator is influenced by direct current high voltage breakdown, and the average acceleration gradient is about 0.5-2 MV/m. Therefore, compared with a direct-current high-voltage accelerator, the accelerator provided by the embodiment has more advantages, no extra-high voltage exists in the accelerator, the overall voltage level is greatly reduced compared with that of the direct-current high-voltage accelerator, the personal safety guarantee requirements on workers are greatly reduced, meanwhile, the occupied area requirements on the accelerator are also greatly reduced, and the MeV-level desktop ion accelerator can be realized by adopting a pulse synchronous acceleration technology.
In addition, the pulse synchronous acceleration principle of the accelerator provided by the embodiment has a certain similarity with the radio frequency synchronous acceleration principle and the induction synchronous principle of the linear radio frequency accelerator, namely, where the ion beam 4 is transmitted, the pulse voltage establishes an accelerating electric field 5 in a corresponding accelerating gap, so that the aim of accelerating the ion beam is fulfilled. The low-energy radio frequency linear accelerator of conventional design has the problems that the flight speed of ions is low, the transit time of the ions is long, the matching of the transit time and an accelerating structure is difficult to realize, and the low ion accelerating efficiency is easy to occur, particularly, the effective accelerating efficiency of the ions is lower in consideration of the high-frequency loss problem of the radio frequency accelerator.
The accelerator provided by the embodiment can enable the ion beam 4 to feel the existence of the accelerating electric field in the whole movement process, and the pulse synchronous linear accelerator can conveniently solve the problem that the accelerating phase of the radio frequency accelerator is not matched with the ion transit time due to the adoption of the low-voltage synchronous control technology to control the output time of the pulse voltage, so that the accelerating efficiency of the accelerator is improved, and meanwhile, the high-frequency loss of a radio frequency power source and the technical and engineering problems caused by the high-frequency loss are avoided. The high transit time factor (close to 1) has no problem that the accelerating phase of the radio frequency accelerator is not matched with the ion transit time because a mode of loading high-voltage pulses in a time sequence is adopted.
In this embodiment, all the accelerating cells 1 are serially arranged step by step, so that the accelerating transport channels 2 are in a linear arrangement, that is, the accelerating transport channels 2 formed by all the accelerating cavities 13 are in a linear track. The linear track herein refers to a linear motion trajectory space capable of providing the ion beam 4 with a certain (width) amplitude, that is, a linear space is provided in the linear track, especially, the linear space (for the ion beam 4 to pass through) is located in the middle of the linear track, and whether the two sides of the linear space are even and straight does not affect the motion trajectory of the ion beam 4. Meanwhile, the acceleration effect and efficiency of the accelerator can be more highlighted by adopting the linear track, so that the ion beam is always in an acceleration phase sufficiently and timely, and the accelerator is particularly suitable for accelerating the ion beam 4 with low energy. Preferably, the accelerating cavity 13 is a columnar cavity, and the columnar cavity may be a regular prism, a cylinder or other shapes with a central axis, so that a uniform space with equal width is provided for the movement track of the ion beam 4 in the accelerating cavity 13, and no excessive influence on the acceleration of the ion beam 4 occurs. All the columnar cavities form an acceleration section, namely the acceleration transmission channel 2 is not provided with a field-free drift tube on the axis of the acceleration section, pulse voltage is adopted for power supply, and the acceleration units are connected in series step by step, so that the acceleration section has higher average acceleration gradient which can reach 10MV/m order, and the whole ion accelerator is compact and small.
The accelerating unit 1 is mainly used for forming an accelerating cavity 13, and can smoothly form an accelerating electric field in the accelerating cavity 13, so as to carry out linear acceleration on the ion beam 4, in order to meet the advantages of compact structure and high accelerating efficiency of the accelerating unit 1, in this embodiment, the accelerating unit 1 comprises two conductors 11 and an insulator 12 arranged between the two conductors 11, the insulator 12 plays a supporting and blocking role, the accelerating cavity 13 is formed in the accelerating unit, normal formation of the accelerating cavity 13 can be maintained, each conductor 11 is provided with a conducting end connected into the accelerating cavity 13, and the pulse power source is connected with the two conductors 11 as positive and negative poles through a high-voltage feed cable 6, so that the two conductors 11 can form an electric field 5 in the same direction as the advancing direction of the ion beam 4 in the accelerating cavity 13. That is, after the two conductors 11 are connected with the pulse power source and serve as positive and negative electrodes respectively, an electric field 5 for accelerating the ion beam 4 can be formed in the accelerating cavity 13, so that the ions moving into the corresponding accelerating cavity 13 can be effectively accelerated in time under the action of the formed electric field 5, and the purpose of gradually accelerating the ion beam 4 in the whole accelerating transmission channel 2 is finally achieved. Through the design, the accelerator of the embodiment has the advantages of compact structure and high acceleration efficiency, and can realize the adjustment of beam energy by controlling the amplitude of acceleration voltage or the number of loading power sources according to the actual application requirements, so that the aim of conveniently adjusting the beam energy is fulfilled.
In order to further realize that the ion beam 4 can more approach to and even realize seamless acceleration between the adjacent accelerating cavities 13, the conductors 11 close to each other in the adjacent accelerating cavities 13 are arranged in series, and the series arrangement indicates that the adjacent conductors 11 of different units are directly close to each other in series, so that the adjacent formed electric fields 5 are close enough, the transition distance of the gap between the adjacent electric fields 5 of the ion beam 4 is reduced, and the aim of further improving the ion acceleration efficiency is fulfilled. Preferably, in the adjacent accelerating cavities 13, the conductors 11 close to each other are integrally arranged, namely, a direct integral series connection mode is adopted, when the conductors 11 close to each other in different units are connected in series or integrally arranged, the situation that the corresponding conductors 11 of the adjacent accelerating units 1 share electrodes can occur, at this time, a radial isolating magnetic core 7 needs to be sleeved on the high-voltage feed cable 6, the radial isolating magnetic core 7 is regarded as a large inductance, and leakage current is prevented from flowing, so that smooth establishment of the electric field 5 is ensured; likewise, the end of the acceleration transmission channel 2 is provided with an axially isolating magnetic core 8, also in order to ensure a smooth establishment of the electric field throughout the end. The specific composition of the isolation magnetic core can be ferrite or amorphous material magnetic core.
Specifically, taking two acceleration units 1 at the starting end as examples, namely a unit a and a unit B respectively, wherein in the unit a, a conductor 11 close to the starting end is used as a zero potential electrode, and a conductor 11 far from the starting end is used as a negative high voltage electrode; in the unit B, the conductor 11 near the starting end is used as a floating potential ground electrode, and shares one electrode with the negative high voltage electrode in the unit a, if the radial isolating magnetic core 7 is not sleeved, the current provided by the pulse power source during operation flows from the floating ground potential electrode of the unit B to the negative high voltage electrode of the unit a (the current can be understood as bypass current or leakage current), and if the leakage current flowing to the bypass is too large, the accelerated electric field 5 cannot be successfully established in the unit B. In the unit B, the conductor 11 far from the starting end is used as a negative high-voltage electrode, which shares one electrode with the suspension potential ground electrode of the following accelerating unit 1, and the radial isolating magnetic core 7 is also required to be sleeved on the high-voltage feed cable 6 connected to the conductor, wherein the rubber-insulated wire 61 of the high-voltage feed cable 6 is connected to the shared electrode near to the starting end in the corresponding accelerating unit 1, and the core wire 62 of the high-voltage feed cable 6 is connected to the shared electrode far from the starting end. Through the design, the series connection form of all the electric fields 5 can be truly realized, and even the seamless connection process is approached (if the electrodes are small enough, the electric fields 5 can be theoretically realized, so that the aim that the ion beam 4 is always in an acceleration phase and the high acceleration efficiency is achieved.
Considering the purpose of realizing the high average acceleration gradient of the ion beam 4, the conductor 11 and the insulator 12 are both in a coaxial annular structure, the inner hole of the insulator 12 forms the acceleration cavity 13, through the design, the electric field 5 can be formed around the circumference in the acceleration cavity 13, so that in each acceleration unit 1, the design form of the two conductors 11 and the insulator 12 is identical to that of a diode type acceleration structure, in particular, a flat electrode structure perpendicular to the axial direction of the acceleration cavity 13 can be realized, and a certain included angle can exist between the normal line of the flat electrode structure and the axial direction of the acceleration cavity 13 in other embodiments. Returning to the diode type accelerating structure of the unipolar voltage pulse in this embodiment, the electric field 5 of the gap acceleration may be greater than 10MV/m, and theoretically no drift tube is needed, because the accelerator adopts the unipolar pulse electric field to accelerate ions, compared with the direct current electric field to accelerate ions, the requirement on the insulation support of the accelerator is reduced (the breakdown field strength of the insulation support at the pulse voltage is greater than the breakdown field strength at the direct current voltage); in addition, compared with the acceleration of ions by a radio frequency electric field, the problem of high-frequency power loss is avoided, and therefore, the average acceleration gradient of the accelerator provided by the embodiment can be higher.
By adopting the annular conductor 11, namely the annular diode type accelerating structure, the axial electric field 5 can be established simultaneously to accelerate the ion beam, the radial electric field to focus the ion beam 4 can be established, the diode type accelerating structures are serially connected, the inside is vacuumized, acceleration, transmission and focusing channels of the ion beam 4 can be formed, and the beam current transportation does not need an external magnetic field. By changing the shape (electrode group) of the electrodes in the plurality of diode-type acceleration chambers to accelerate and focus ions, stable transportation of the low-energy ion beam 4 can be achieved. On the basis of the diode type accelerating structure connected in series, the radial isolating magnetic core 7 is sleeved on the high-voltage feed cable 6, so that leakage current can be reduced, the establishment of an accelerating electric field of each stage of accelerating cavity is ensured, and the purposes of high efficiency and high gradient acceleration are realized. When the accelerator is used for analyzing the ion beam 4, the measurement is convenient and the sensitivity is high; the pulse beam flow provided by the accelerator is a micro beam group with controllable duration, so that the accelerator is suitable for the use of a time-of-flight method in the analysis of the ion beam 4 on one hand, and can also improve the sensitivity of the analysis of the ion beam 4 on the other hand.
In this embodiment, the insulator 12 is sleeved with the matching resistive loop 14, so that the output impedance of the pulse high voltage can be matched and eliminated, and the distortion phenomenon of the output waveform of the pulse voltage is avoided. The matching resistor ring 14 is provided with an insulating medium layer 15, that is, the whole matching resistor ring 14 is immersed in the insulating medium layer 15, the insulating medium layer 15 can be insulating gas or insulating oil liquid, transformer oil can be adopted here, so that the matching resistor ring 14 and the accelerating unit 1 are in a vacuum insulation state, and the external interface surface flashover of the accelerating unit 1 can be prevented. In addition, an axial isolation core 8 and an analyzing magnet 9 are provided at the end acceleration unit 1, and as described above, the axial isolation core 8 is used to ensure smooth establishment of the subsequent electric field 5, the analyzing magnet 9 can screen the ion beam 4 which has been accelerated, and in combination with other methods, can measure the energy of the ion beam 4, and can also transmit the ion beam 4 to a place where it is needed.
Through the above design, the accelerator provided in this embodiment has the advantages of both a dc type accelerator and a radio frequency type accelerator, such as the advantages including a dc type high voltage accelerator: full ion acceleration, high transit time factor and electric focusing; also contains the advantages of RFQ: high acceleration gradient and no need of externally adding focusing magnetic field; meanwhile, the system has the advantages of simple and compact peripheral system and capability of realizing a desktop accelerator. The low-energy heavy ion acceleration scheme provides a serious challenge for the aspects of acceleration efficiency, beam transmission efficiency, ion type compatibility, acceleration gradient and the like due to the characteristics of low speed, strong space charge effect, large speed change range in the acceleration process, large difference of charge-mass ratios of ions to be accelerated and the like. By adopting the accelerator scheme of the embodiment, the accelerator has a continuously assembled diode type accelerating and focusing structure, the space position and speed information of ions can be predicted through the whole process, the time sequence of the accelerating electric field 5 on the diode accelerating structure is controlled to be established, the ion beam 4 is always in the accelerating field, and the low-energy heavy ions are accelerated with high gradient and high efficiency.
The present embodiment also provides a low-energy heavy ion acceleration method, which can be implemented based on the above-mentioned accelerator, and of course, the acceleration of low-energy heavy ions can also be implemented by constructing other accelerators with the key features of the above-mentioned accelerator, specifically, pulse power sources are controlled to step-by-step load voltages on all acceleration units 1 according to a certain time sequence, and electric fields 5 are formed in the acceleration cavities 13 corresponding to the acceleration units 1, so that ions just moving into the acceleration cavities 13 forming the electric fields 5 are accelerated, and finally step-by-step acceleration of the ion beam 4 is implemented. Referring again to fig. 2, the acceleration principle is that the ion beam 4 extracted by the ion source 3 is at t A When reaching the accelerating cavity A at any time, the pulse high voltage A output by the pulse power source is synchronously loaded to the accelerating cavity A, and the ion beam 4 is in an accelerating electric field E A Is accelerated under the action of (a); when the ion beam is at t B When reaching the accelerating cavity B, the accelerating electric field E established by the pulse high voltage B B The ion beam 4 is accelerated again, thereby realizing that the ion beam 4 is always in an acceleration phase and realizing the purpose of gradual acceleration. It should be noted that addThe speed unit 1 can be constructed in other ways, and the acceleration method can be applied to accelerate the vehicle as long as the equivalent replacement is performed within the scope of the invention and principles of the application, but the accelerator provided by the embodiment is optimized for the inventor or a common accelerator scheme, and does not prevent other people from adopting equivalent replacement means to achieve the corresponding acceleration purpose based on the inventive concept.
The time sequence control of the pulse power source refers to: the position reached by the ion beam 4 is predicted according to the energy and the type of the ion beam 4 to be accelerated and the structural length of the whole acceleration transmission channel 2, so that when the ion beam 4 reaches the next acceleration cavity 13 is calculated, and finally, the pulse power source controls the loading voltage according to a certain time sequence. That is, in the pulse synchronous acceleration process, different pulse voltage loading time sequences (the time sequences are realized by a time sequence control circuit in a pulse power source, which is a relatively mature means at present and is not repeated here) can be set according to different charge-to-mass ratios, different initial energies and expected energy gains obtained in the acceleration transmission channel 2 of the ion beam 4, so that the efficient acceleration of any ion beam 4 is realized, the time-space relationship between the speed, the spatial position and the time of target ions and the acceleration field is predicted in the whole process, and the establishment of the pulse acceleration electric field 5 and the spatial position synchronization of the pulse ion beam 4 are realized by means of time synchronization (the time sequences established by the control electric field 5), so that the ion beam 4 is always in an acceleration phase, and the efficient acceleration is realized.
Further, the power output by each pulse voltage of the pulse power source to the accelerating cavity 13 can be regarded as constant, the arrival position of the ion beam 4 is predicted according to the energy, the type and the length of the accelerating structure of the ion beam 4, whether the ion beam 4 reaches the next accelerating cavity 13 is judged, if so, the accelerating electric field 5 of the accelerating cavity 13 is established by adjusting the time sequence of the pulse power source corresponding to the corresponding accelerating cavity 13, and the ion beam 4 is accelerated. The electric field 5 of the acceleration chamber 13 is maintained until the ion beam 4 passes through the acceleration chamber 13, and the electric field 5 is completed when the ion beam 4 passes through the acceleration chamber 13. Since the pulse voltage is not a perfect square wave, the electric field generated adjacent to the accelerating cavity 13 affects the electric field 5 of the accelerating cavity 13, and many other factors affect the electric field 5 of the accelerating cavity 13. Thus, the electric fields 5 are completed in time, and the influence between the adjacent electric fields 5 can be reduced, so that it is ensured where the ion beam 4 goes to, where the accelerating electric field 5 is established, the ion beam 4 is accelerated, and the process is completed. By the control design, the compatibility of the ion species to be accelerated is higher, namely, the initial speed and the charge-to-mass ratio of the ions are almost not particularly selected, and the acceleration of any ion beam 4, including ion beams, high-charge-state heavy ion beams, cluster ion beams and the like, can be realized by controlling the time sequence of outputting high-voltage pulses.
In summary, the accelerator and the accelerating method provided in this embodiment can implement a scheme of high-efficiency acceleration on low-energy heavy ions, solve the problems of low-energy and different charge-to-mass ratio ion beams 4 (especially multi-charge heavy ions) in low-energy section acceleration, implement high-efficiency, full-ion and high-gradient acceleration on heavy ions, provide a target parameter ion beam with a wider range for application research of ion beam analysis, nuclear physics and the like, and provide a brand-new solution for a low-energy ion implanter of a high-energy ion synchrocyclotron, so as to promote development of low-energy ion (especially heavy ion) accelerating technology.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that the structures or components illustrated in the drawings are not necessarily drawn to scale, and that descriptions of well-known components and processing techniques and procedures are omitted so as not to unnecessarily limit the present invention.