A multi-functional radial probe device and cyclotron

Abstract

The application discloses a multifunctional radial probe device and a cyclotron, and a method, the multifunctional radial probe device comprises a radial probe, a strip ionization chamber and a processor, a beam passes through the strip ionization chamber and enters the radial probe, and the beam transmittance of the strip ionization chamber is greater than a preset threshold value; wherein the processor is used for calculating the beam position according to the induced current gradient distribution measured by the strip ionization chamber, and calculating the beam intensity according to the measurement result of the radial probe. The embodiment of the application can simultaneously on-line and real-time measure the beam intensity and the beam spot position by using an integrated radial probe. The application can be widely applied to the technical field of cyclotrons.

Description

Technical Field

[0001] This application relates to the field of cyclotron technology, and more particularly to a multifunctional radial probe device and a cyclotron. Background Technology

[0002] In related technologies, several radial probes are used for debugging cyclotrons: integrating radial probes, differentiating radial probes, and visualization radial probes. Integrating radial probes are used to measure beam intensity (current in the nA range); visualization radial probes are used to measure the vertical oscillation of the beam within the cyclotron (defined as the Z-direction). The basic principle is to use a camera placed at the tail of the radial probe to photograph a ceramic panel at the head of the probe (the radial probe has a lens in the middle to isolate a vacuum). When the beam hits this ceramic panel, it emits a light spot. The light spot captured by the camera at different radial positions (i.e., the direction of insertion and exit from the accelerator) will change in the Z-direction. The position of the light spot is then calculated through image recognition and compared. However, only one of these two types of radial probes can be installed at a time, causing inconvenience for testing, namely, the inability to simultaneously measure beam intensity and beam axial position online in real time. Summary of the Invention

[0003] The main objective of this application is to propose a multifunctional radial probe device and cyclotron, which can simultaneously measure beam intensity and beam spot position online in real time using an integrated radial probe.

[0004] To achieve the above objectives, one aspect of this application proposes a multifunctional radial probe device, comprising a radial probe, a strip ionization chamber, and a processor. A beam passes through the strip ionization chamber and then enters the radial probe. The beam penetration rate of the strip ionization chamber is greater than a preset threshold. The processor is configured to calculate the beam position based on the induced current gradient distribution measured in the strip ionization chamber, and to calculate the beam intensity based on the measurement results of the radial probe.

[0005] In some embodiments, the strip ionization chamber includes transverse strips and / or longitudinal strips.

[0006] In some embodiments, the strip ionization chamber includes a plurality of strips with a first equal spacing, the first equal spacing being determined according to spatial resolution, and the width of the strips being smaller than the first equal spacing.

[0007] In some embodiments, the strip ionization chamber further includes protective electrodes disposed between the strips or on both sides of the edges of all the strips.

[0008] In some embodiments, the strip ionization chamber includes a plurality of strips with a second equal spacing, the second equal spacing being determined according to the size of the strip ionization chamber and the number of strips, and the width of the strips being determined according to the fill factor and the second equal spacing.

[0009] In some embodiments, the strip material of the strip ionization chamber includes a conductive material, which includes any one or more of metallic materials, carbon-based materials, or polymeric materials.

[0010] In some embodiments, the strip thickness of the strip ionization chamber ranges from 12 μm to 500 μm.

[0011] In some embodiments, the spacing between the positive and negative electrodes of the strip ionization chamber ranges from 2 mm to 10 mm.

[0012] In some embodiments, the radial probe includes an integrating probe radial probe.

[0013] To achieve the above objectives, another aspect of the embodiments of this application proposes a cyclotron accelerator, including the aforementioned multifunctional radial probe device.

[0014] The embodiments of this application include at least the following beneficial effects: This application provides a multifunctional radial probe device and a cyclotron accelerator. The multifunctional radial probe device includes a radial probe, a strip ionization chamber, and a processor. The beam enters the radial probe after passing through the strip ionization chamber. The beam penetration rate of the strip ionization chamber is greater than a preset threshold, which reduces the attenuation of the beam after passing through the strip ionization chamber. The processor is used to calculate the beam position based on the induced current gradient distribution measured in the strip ionization chamber, and to calculate the beam intensity based on the measurement results of the radial probe, thereby using an integrated radial probe to simultaneously measure the beam intensity and beam spot position online in real time. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the multifunctional radial probe device provided in the embodiments of this application; Figure 2 (a) is a front view of the strip ionization chamber provided in an embodiment of this application; Figure 2 (b) is a side view of the strip ionization chamber provided in an embodiment of this application; Figure 3 This is a front view of the strip structure of the strip ionization chamber provided in the embodiments of this application; Figure 4 This is a side view of the strip structure of the strip ionization chamber provided in the embodiments of this application; Figure 5 This is a rendered schematic diagram of the strip ionization chamber provided in the embodiments of this application. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0017] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0018] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0020] See Figure 1-5 This application provides a multifunctional radial probe device, which includes a radial probe (1-3), a strip ionization chamber (1-2), and a processor. The beam (1-1) passes through the strip ionization chamber (1-2) and then enters the radial probe (1-3). The beam penetration rate of the strip ionization chamber (1-2) is greater than a preset threshold. The processor is used to calculate the beam position based on the induced current gradient distribution measured in the strip ionization chamber (1-2) and to calculate the beam intensity based on the measurement results of the radial probe (1-3).

[0021] It should be noted that the preset threshold is determined according to the actual application, and this embodiment does not make specific requirements. For example, if the beam penetration rate of the strip ionization chamber is greater than 99%, the high beam penetration rate of the strip ionization chamber can reduce the influence of the strip ionization chamber on the subsequent radial probe detection results.

[0022] When the beam (charged particles) enters the strip ionization chamber filled with working gas, it collides with gas molecules to produce ionization, forming positive and negative ion pairs. An external electric field pulls electrons towards the positive electrode and positive ions towards the negative electrode, forming a weak ionization current. Several strips are etched on the positive and negative electrodes of the strip ionization chamber, each strip connecting to an independent electronic channel. The current is amplified and the beam position is calculated by inducing the current gradient distribution. After passing through the strip ionization chamber, the charged particles are injected into the integrating probe. Therefore, accurate beam intensity can be obtained with the beam position information.

[0023] In some embodiments, the strip ionization chamber includes transverse strips and / or longitudinal strips.

[0024] The transverse strip is used to measure the axial position, and the longitudinal strip is used to measure the radial position. In practical applications, the transverse strip or the longitudinal strip is set according to the application requirements, or both transverse strip and longitudinal strip are set at the same time.

[0025] When the beam hits the horizontal strip, it produces a corresponding Gaussian distribution, which is a bell-shaped curve. The highest point can be understood as its position. Similarly, when it hits the vertical strip, it will also produce a bell-shaped curve, and the highest point is its horizontal position.

[0026] In some embodiments, the strip ionization chamber includes a plurality of strips with a first equal spacing, the first equal spacing being determined according to the spatial resolution, and the width of the strips being smaller than the first equal spacing.

[0027] When the readout mode of the strip ionization chamber is digital readout mode (hit / miss): the spatial resolution is approximately equal to the strip pitch divided by... For simple 1D position resolution, the width of the strip itself is usually slightly smaller than the spacing. Assuming the spatial resolution requirement is 1 mm, the strip spacing is about 3.5 mm and the strip width can be 3 mm. If the typical diameter of the radial probe of the cyclotron is 60 mm (pipe size), then the number of strips in the strip ionization chamber is about 60 / 3.5≈17.

[0028] In some embodiments, the strip ionization chamber further includes protective electrodes disposed between the strips or on both sides of the edges of all the strips.

[0029] To achieve higher spatial resolution, more stripes are needed (meaning smaller stripe spacing at a fixed size). The more stripes there are, the more harmful "crosstalk" the induced charge spreads to adjacent stripes becomes, which must be suppressed by the following means: (1) Guard electrodes: Guard electrodes (ground strips) are placed between or on both sides of the signal strips to absorb edge electric fields and isolate the signal. (2) Electronic discrimination: Set appropriate circuit thresholds to ignore small signals on adjacent strips.

[0030] In some embodiments, the strip ionization chamber includes a plurality of strips with a second equal spacing, the second equal spacing being determined according to the size of the strip ionization chamber and the number of strips, and the width of the strips being determined according to the fill factor and the second equal spacing.

[0031] When the readout mode of the strip ionization chamber is the analog readout mode (charge centroid method): as the ionized electron cloud drifts in the ionization chamber, it is not collected by a single strip; its electric field is simultaneously coupled to multiple strips. The induced signals of charge on multiple strips are actively utilized, and the linearity of charge distribution is optimized through electric field simulation to ensure that the charge is effectively distributed across multiple strips. Since 32-channel or 64-channel preamplifiers / ASIC chips are common in electronics, the number of strips is between 32 and 64 for ease of implementation and cost control. Assuming 48 strips, the center-to-center spacing is 60mm / 48 = 1.25mm. The strip width is determined by the "fill factor," which is calculated as strip width / center-to-center spacing. The fill factor is typically less than 1. Empirical values ​​and simulations show that a classic and effective ratio is between 1 / 3 and 2 / 3. An excessively high fill factor (close to 1) will cause the charge to be too concentrated on a single strip, which is detrimental to interpolation; an excessively low fill factor (close to 0) will result in a weak signal and poor signal-to-noise ratio. Assuming a value of 0.4, then the strip width = fill factor × center spacing = 0.4 × 1.25 mm = 0.5 mm.

[0032] In some embodiments, the strip material of the strip ionization chamber includes a conductive material, which includes any one or more of metallic materials, carbon-based materials, or polymeric materials.

[0033] It should be noted that the strip material in the strip ionization chamber includes highly conductive materials, including but not limited to metals such as gold, silver, and copper; carbon-based materials such as graphene and carbon nanotubes; and polymeric materials such as doped polyacetylene, polypyrrole, polyaniline, and poly(3,4-ethylenedioxythiophene) (PEDOT). The strip can be etched from a polyester Mylar film coated with the corresponding conductive metal.

[0034] In some embodiments, the strip thickness of the strip ionization chamber ranges from 12 μm to 500 μm.

[0035] The strip thickness range of the strip ionization chamber covers 12 micrometers to 500 micrometers, and 35 micrometers is sufficient for this application.

[0036] In some embodiments, the spacing between the positive and negative electrodes of the strip ionization chamber ranges from 2 mm to 10 mm.

[0037] The gap between the two electrodes of the strip ionization chamber is generally between 2mm and 10mm, and is 5mm in this application embodiment. A high voltage forms an electric field between the two electrodes of the ionization chamber. Generally, a voltage of 1.2kV is applied to the cathode, and the anode is grounded to 0V. The ionization signal generated by the strip is extracted from the strip through capacitive coupling (or resistive voltage division) and sent to the preamplifier. nA level current converted to µV The voltage signal is in the mV range, and the amplified voltage signal is fed into a high-speed ADC and FPGA for real-time beam spot reconstruction.

[0038] In some embodiments, the radial probe includes an integrating probe radial probe.

[0039] It should be noted that the radial probe is determined based on the actual application, and this embodiment does not impose specific limitations. The radial probe includes, but is not limited to, the integrating probe and the radial probe.

[0040] This application also provides a cyclotron accelerator, including the above-described multifunctional radial probe device.

[0041] A cyclotron is a classic particle accelerator that uses a constant magnetic field and a high-frequency alternating electric field to accelerate charged particles (such as protons, deuterons, and alpha particles). Its core idea is to make particles spiral through a magnetic field and repeatedly pass through an electric field gap to gain energy. The cyclotron also includes a shell and other hardware structures, such as a magnet system to generate a strong and uniform constant magnetic field perpendicular to the plane of particle motion; a vacuum chamber to provide a high-vacuum environment, located between two magnetic pole faces; an electrode system to generate a high-frequency electric field to accelerate particles; a high-frequency oscillation system to generate a high-frequency alternating electric field between two D-shaped boxes; a particle source and injection system to generate charged particles (such as positive ions) to be accelerated at the center of the vacuum chamber; a particle extraction system to "kick" the particles off their circular orbit and guide them toward the experimental target after they have been accelerated to their final energy; and auxiliary and control systems, such as a cooling system that uses water or air cooling to maintain stable operation, a power supply system that provides a stable high-power DC current to the excitation coils to power the high-frequency oscillator and other subsystems, and a control system that monitors and adjusts parameters such as magnetic field strength, high-frequency frequency, vacuum level, and beam intensity.

[0042] The embodiments of this application include at least the following beneficial effects: This application provides a multifunctional radial probe device and a cyclotron accelerator. The multifunctional radial probe device includes a radial probe, a strip ionization chamber, and a processor. The beam enters the radial probe after passing through the strip ionization chamber. The beam penetration rate of the strip ionization chamber is greater than a preset threshold, which reduces the attenuation of the beam after passing through the strip ionization chamber. The processor is used to calculate the beam position based on the induced current gradient distribution measured in the strip ionization chamber, and to calculate the beam intensity based on the measurement results of the radial probe, thereby using an integrated radial probe to simultaneously measure the beam intensity and beam spot position online in real time.

[0043] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0044] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0045] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0046] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0047] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0049] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A multifunctional radial probe device, characterized in that, The multifunctional radial probe device includes a radial probe, a strip ionization chamber, and a processor. The beam current enters the radial probe after passing through the strip ionization chamber, and the beam penetration rate of the strip ionization chamber is greater than a preset threshold. The processor is configured to calculate the beam position based on the induced current gradient distribution measured in the strip ionization chamber, and to calculate the beam intensity based on the measurement results of the radial probe.

2. The multifunctional radial probe device according to claim 1, characterized in that, The strip ionization chamber includes transverse strips and / or longitudinal strips.

3. The multifunctional radial probe device according to claim 1, characterized in that, The strip ionization chamber includes a plurality of strips with a first equal spacing, the first equal spacing being determined according to spatial resolution, and the width of the strips being smaller than the first equal spacing.

4. The multifunctional radial probe device according to claim 3, characterized in that, The strip ionization chamber also includes protective electrodes, which are disposed between the strips or on both sides of the edges of all the strips.

5. The multifunctional radial probe device according to claim 1, characterized in that, The strip ionization chamber includes a plurality of strips with a second equal spacing, the second equal spacing being determined according to the size of the strip ionization chamber and the number of strips, and the width of the strips being determined according to the fill factor and the second equal spacing.

6. The multifunctional radial probe device according to any one of claims 1-5, characterized in that, The strip material of the strip ionization chamber includes a conductive material, which includes any one or more of metallic materials, carbon-based materials, or polymeric materials.

7. The multifunctional radial probe device according to claim 6, characterized in that, The strip thickness of the strip ionization chamber ranges from 12 μm to 500 μm.

8. The multifunctional radial probe device according to claim 6, characterized in that, The spacing between the positive and negative electrodes of the strip ionization chamber ranges from 2mm to 10mm.

9. The multifunctional radial probe device according to any one of claims 1-5, characterized in that, The radial probe includes an integrating probe radial probe.

10. A cyclotron, characterized in that, Includes the multifunctional radial probe device as described in any one of claims 1-9.

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