An online proton imaging ion spectrometer diagnostic system

Abstract

The application discloses an online proton imaging ion spectrometer diagnosis system, relates to the fields of plasma physics and nuclear detection, and comprises an online proton imaging module, an online Thomson ion spectrometer module and a shielding aiming module; the shielding aiming module comprises a shielding cavity and an aiming laser pen; the online proton imaging module comprises a metal filter, a first scintillator and two proton imaging acquisition assemblies; the proton imaging acquisition assembly comprises a first optical fiber panel attached to the first scintillator and a first CMOS sensor attached to the first optical fiber panel; the online Thomson ion spectrometer module comprises an ion beam deflection mechanism and an ion spectrum diagnosis acquisition assembly; the ion spectrum diagnosis acquisition assembly comprises a light-proof aluminum film, a second scintillator, a second optical fiber panel and a second CMOS sensor which are sequentially and superposedly arranged. The application reduces the size of the whole system, can simultaneously carry out online proton imaging and ion energy spectrum diagnosis, and can effectively prevent radiation damage to the CMOS chip.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plasma physics and nuclear detection, in particular to an online proton imaging ion spectrometer diagnosis system. BACKGROUND

[0002] The experimental research of super strong ultra-short laser and plasma interaction requires the measurement of ion energy spectrum and proton beam spot generated by laser target. The current proton imaging system usually adds a mirror, a lens and the like behind a scintillator, and finally images to a CCD for recording, which has a complex structure and occupies a large space.

[0003] For the diagnosis of ion energy spectrum, the existing methods include an ion spectrometer based on MCP, an ion spectrometer based on a scintillator, and an ion spectrometer based on a CMOS chip. The ion spectrometer based on MCP has a higher requirement for vacuum degree due to the use of MCP, and a vacuum chamber system (equipped with a special vacuum unit) independent of the vacuum target chamber of the experiment is needed. The ion spectrometer system based on a scintillator uses an optical lens to collect light, and an EMCCD is needed to improve the signal gain and the signal-to-noise ratio due to the low light collection efficiency of the lens, which is only a few per thousand to a few per ten thousand. The ion spectrometer based on a CMOS chip has a higher spatial resolution because ions directly incident on the CMOS chip deposit energy to convert into an electrical signal, and it has a compact structure, a low requirement for vacuum degree, and a low cost. It is a better choice for future development of ion online diagnosis, but there is a problem of chip radiation damage. SUMMARY

[0004] The purpose of the present application is to provide an online proton imaging ion spectrometer diagnosis system to solve the problem that the existing diagnosis method cannot simultaneously carry out online proton imaging and ion energy spectrum diagnosis, and to provide a compact scheme design.

[0005] To achieve the above-mentioned purpose, the technical solutions adopted by the present application are as follows:

[0006] An online proton imaging ion spectrometer diagnosis system, comprising an online proton imaging module, an online Thomson ion spectrometer module and a shielding and aiming module;

[0007] The shielding and aiming module comprises a shielding cavity and an aiming laser pen, the aiming laser pen is installed at the last end of the shielding cavity, a straight-line diagnosis path arranged in the front-rear direction is arranged at the central axis of the shielding cavity, through holes are formed in the front and rear ends of the shielding cavity along the straight-line diagnosis path, the online proton imaging module and the online Thomson ion spectrometer module are installed in the shielding cavity and sequentially pass through the straight-line diagnosis path from front to back, and the laser emission direction of the aiming laser pen coincides with the straight-line diagnosis path from back to front.

[0008] The online proton imaging module comprises a metal filter, a first scintillator and two proton imaging acquisition assemblies; the metal filter is opposite to the straight-line diagnosis path, and a through hole coinciding with the straight-line diagnosis path is arranged at the center position; the proton imaging acquisition assembly comprises a first optical fiber panel (1-3) and a first CMOS sensor (1-4), the first optical fiber panel (1-3) is inclined to the first scintillator (1-2), the first optical fiber panel (1-3) is a right-angled trapezoidal plate, the inclined waist surface of the first optical fiber panel (1-3) is attached to the rear surface of the first scintillator (1-2), and the first CMOS sensor (1-4) is attached to the right-angled waist surface of the first optical fiber panel (1-3); the first optical fiber panels (1-3) of the two proton imaging acquisition assemblies form a V-shaped structure with the V groove facing backward, and the left and right edges of the V groove are symmetrically distributed on the left and right sides of the straight-line diagnosis path.

[0009] The online Thomson ion spectrometer module comprises an ion beam deflection mechanism and an ion spectrum diagnosis acquisition assembly; in the direction away from the ion beam deflection mechanism, the ion spectrum diagnosis acquisition assembly comprises a light-proof aluminum film, a second scintillator, a second optical fiber panel and a second CMOS sensor arranged in sequence and overlapped, the ion spectrum diagnosis acquisition assembly does not pass through the straight-line diagnosis path, and under the deflection action of the ion beam deflection mechanism, the ion beam passing through the online proton imaging module from front to back and located on the straight-line diagnosis path can be deflected and shot to the ion spectrum diagnosis acquisition assembly.

[0010] In a preferred embodiment of the present application, the aiming laser pen is mounted on the last end of the shielding cavity through an adjusting support, the angle of the laser emission direction of the aiming laser pen can be adjusted through the adjusting support, and the laser emission direction of the aiming laser pen coincides with the straight-line diagnosis path.

[0011] In a preferred embodiment of the present application, the metal filter is formed by four square filters with different thicknesses arranged in a checkered pattern.

[0012] In a preferred embodiment of the present application, the online proton imaging module further comprises an adjusting support plate, the metal filter, the first scintillator, the first optical fiber panel and the first CMOS sensor are all mounted on the top surface of the adjusting support plate, and the adjusting support plate can be adjusted and moved in the horizontal direction and the vertical direction.

[0013] In a preferred embodiment of the present application, the ion beam deflection mechanism comprises a dipole magnet, an electrode plate, a high-voltage connecting cable and a micro high-voltage power supply; the dipole magnet is provided with a collimating hole coinciding with the through hole structure of the straight-line diagnosis path, the central axis extension line of the collimating hole passes through the middle gap of the electrode plate; the ion spectrum diagnosis acquisition assembly is inclined to the straight-line diagnosis path and faces the electrode plate.

[0014] In a preferred embodiment of the present application, the electrode plate comprises two wedge-shaped copper plates symmetrically and parallelly arranged on the left and right sides of the linear diagnostic path; the wedge-shaped copper plate comprises four right-angle edges and one oblique edge.

[0015] In a preferred embodiment of the present application, the shielding cavity is made of lead and / or tungsten.

[0016] Compared with the prior art, the present application has the following beneficial effects:

[0017] 1) The structure of coupling CMOS with optical fiber panel is adopted, the whole system is integrated in a small shielding cavity, realizing compact design, reducing the size of the whole system, and the structure is simple and the cost is low;

[0018] 2) The inclined optical fiber panel is adopted, the middle region is free of optical fiber panel material, which can allow ion beam to pass through the online proton imaging module for subsequent ion spectrum diagnosis, thus realizing online proton imaging and ion spectrum diagnosis at the same time;

[0019] 3) The inclined optical fiber panel makes the CMOS not face the ion beam, which can effectively prevent radiation damage to the CMOS chip.

[0020] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the following embodiments of the present application are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0022] Figure 1 The online proton imaging ion spectrometer diagnostic system provided by the present application is shown in the schematic diagram;

[0023] Figure 2 The online proton imaging module structure provided by the present application is shown in the schematic diagram;

[0024] Figure 3 The online Thomson ion spectrometer module structure provided by the present application is shown in the schematic diagram;

[0025] Figure 4 The shielding aiming module structure provided by the present application is shown in the schematic diagram;

[0026] In the figure: 1, online proton imaging module; 2, online Thomson ion spectrometer module; 3, shielding aiming module; 1-1, metal filter; 1-2, first scintillator; 1-3, first optical fiber panel; 1-4, first CMOS sensor; 1-5, adjusting support plate; 2-1, collimation hole; 2-2, dipole magnet; 2-3, electrode plate; 2-4, miniature high-voltage power supply; 2-5, high-voltage connecting cable; 2-6, light-proof aluminum film; 2-7, second scintillator; 2-8, second optical fiber panel; 2-9, second CMOS sensor; 3-1, shielding cavity; 3-2, aiming laser pen; 3-3, adjusting support. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments.

[0028] Please refer to Figure 1 The present application provides an online proton imaging ion spectrometer diagnostic system, which comprises an online proton imaging module 1, an online Thomson ion spectrometer module 2 and a shielding aiming module 3.

[0029] The laser emitted by the aiming laser pen 3-2 of the shielding aiming module 3 successively passes through the online Thomson ion spectrometer module 2 and the online proton imaging module 1, forming an optical axis incident to the target surface of the laser ion acceleration experiment target (installed in front of the online proton imaging module 1 during the experiment), so that the online proton imaging module 1, the online Thomson ion spectrometer module 2 and the aiming laser pen 3-2 are coaxial, i.e. coaxial on the linear diagnostic path. The online proton imaging module 1 is used for online measurement of the angular distribution of laser accelerated protons, and the online Thomson ion spectrometer module 2 is used for measurement of the energy spectrum of laser accelerated ions.

[0030] The process of the experiment using the present system is as follows:

[0031] First, adjust the adjusting support 3-3 (a non-core structure, how to adjust is not shown in the figure, many adjusting devices in the prior art can meet the requirements, and in the present application, it is required to be able to combine up and down to pitch, and combine left and right to rotate to adjust the aiming laser pen 3-2) to an angle, so that the laser emitted by the aiming laser pen 3-2 can exit through the through hole of the shielding cavity 3-1 and the collimation hole 2-1 of the online Thomson ion spectrometer module 2 to the online proton imaging module 1;

[0032] Then the adjusting support plate 1-5 (non-core structure, how to adjust is not shown in the figure, many adjusting devices in the prior art can meet the requirements, and it is required to have two-dimensional adjusting function, that is, horizontal position adjusting and vertical position adjusting) of the online proton imaging module 1 is adjusted, so that the laser can be emitted from the center through hole of the first scintillator 1-2 of the online proton imaging module 1.

[0033] Finally, the whole system is placed on a four-dimensional adjusting platform, and the aiming laser is incident on the target surface of the laser ion acceleration experiment target through adjustment, that is, the aiming of the system is realized.

[0034] Figure 2 The structure diagram of the online proton imaging module 1 provided by the application is shown, and the online proton imaging module 1 includes a metal filter 1-1, a first scintillator 1-2, two proton imaging acquisition assemblies and an adjusting support plate 1-5; the metal filter 1-1 and the first scintillator 1-2 are arranged in front of and behind each other and face the straight-line diagnostic path, and the center positions are provided with through holes coinciding with the straight-line diagnostic path;

[0035] The proton imaging acquisition assembly includes a first optical fiber panel 1-3 and a first CMOS sensor 1-4, the first optical fiber panel 1-3 is inclined to the first scintillator 1-2, the first optical fiber panel 1-3 is a right-angled trapezoidal plate, the inclined waist surface of the first optical fiber panel 1-3 is attached to the rear surface of the first scintillator 1-2, and the first CMOS sensor 1-4 is attached to the right-angled waist surface of the first optical fiber panel 1-3; the first optical fiber panels 1-3 of the two proton imaging acquisition assemblies form a V-shaped structure with the V groove facing backward, and the V grooves are symmetrically distributed on the left and right sides of the straight-line diagnostic path.

[0036] The metal filter 1-1 is composed of four filters with different thicknesses and is formed into a field shape, so that the first scintillator 1-2 at the corresponding position measures protons of different energies, thereby giving the spatial distribution of protons at four energy points, and each filter has a size of 25mm*25mm. In addition, the metal filter 1-1 can also be distributed in a ring around the through hole in the center.

[0037] The first scintillator 1-2 adopts an organic scintillator, model EJ228, thickness 50μm, size 50mm*50mm, and is used to convert the proton signal into a visible light signal.

[0038] The first optical fiber panel 1-3 is inclined to the front and back straight line direction, and is used for transmitting visible light signals to the first CMOS sensor 1-4, and the inclined surface is used to protect the first CMOS sensor 1-4 from direct irradiation, and one first optical fiber panel 1-3 is arranged on each side, so as to leave the middle area, and the ion beam can pass through the middle area to the online Thomson ion spectrometer module 2 for ion energy spectrum diagnosis through the hole (or slit) in the center of the first scintillator 1-2.

[0039] The first CMOS sensor 1-4 is used for recording visible light signals, and the size is 18mm*50mm, and the pixel size is 20um.

[0040] The adjusting support plate 1-5 is used for adjusting the position of the whole structure composed of the metal filter 1-1, the first scintillator 1-2, the first optical fiber panel 1-3 and the first CMOS sensor 1-4.

[0041] The metal filter 1-1 and the first scintillator 1-2 are tightly attached, and a through hole with a diameter of 2mm is arranged in the center, so as to facilitate the ion to enter the online Thomson ion spectrometer for ion energy spectrum diagnosis.

[0042] The two first optical fiber panels 1-3 are inclined to the straight line diagnosis path at an angle of 45 degrees, and the contact surface area of the first scintillator 1-2 is 25mm*50mm. The proton beam incident to the first scintillator 1-2 generates visible light, which is transmitted to the first CMOS sensor 1-4 behind the two first optical fiber panels 1-3, and then the light signal is converted into an electric signal through photoelectric effect, the electric signal is converted into a digital signal through analog-digital conversion, and the digital signal is transmitted to the computer through a data line to realize the recording of proton imaging.

[0043] The adjusting support plate 1-5 in the online proton imaging module 1 has two-dimensional adjusting functions of horizontal movement and vertical movement, and the adjusting range is ±2mm.

[0044] Figure 3 The online Thomson ion spectrometer module 2 provided by the application is shown in the schematic diagram, which comprises a collimating hole 2-1, a dipole magnet 2-2, an electrode plate 2-3, a miniature power supply high-voltage power supply, a light-proof aluminum film 2-6, a second scintillator 2-7 encapsulated with a film, a second optical fiber panel 2-8 and a second CMOS sensor 2-9 behind the second optical fiber panel 2-8, and the second CMOS sensor 2-9 is a strip-shaped structure.

[0045] The diode magnet 2-2 is used to generate a magnetic field, and the strength and direction of the magnetic field can be controlled by adjusting the current. The electrode plate 2-3 is used to control the direction and deflection of the ion beam, and is located downstream of the diode magnet 2-2 to further adjust the beam after magnetic field deflection. The high-voltage connecting cable 2-5 is used to connect the electrode plate 2-3 with the micro high-voltage power supply 2-4, which transmits a high-voltage electric signal to establish the required electric field on the electrode plate 2-3. The micro high-voltage power supply 2-4 is used to provide the required high voltage for the electrode plate 2-3 to form an electric field.

[0046] The inner diameter of the collimating hole 2-12-1 is 0.2mm;

[0047] In the online Thomson ion spectrometer module 2, the electrode plate 2-3 includes two parallel wedge-shaped metal copper plates formed by cutting off the right angle part of a rectangular copper plate, and the copper plate has a thickness of 4mm and a length of 120mm, and the distance between the two wedge-shaped metal copper plates is 10mm.

[0048] Compared with the existing scintillator coupling lens method, the present application adopts the structure of fiber panel coupling CMOS, which has sufficient light collection efficiency and does not require as high a vacuum degree as MCP. After deflection by the diode magnet 2-2, only ions, not electrons and X-rays, are incident on the second CMOS sensor 2-9. The fiber panel with a certain thickness (the thickness is determined according to the actual generated ions) can prevent ions from directly entering the CMOS chip, thereby providing a certain radiation protection for the CMOS chip.

[0049] Figure 4 The shielding aiming module 3 provided by the present application includes a shielding cavity 3-1, an aiming laser pen 3-2, and an adjusting support 3-3 for adjusting the posture of the aiming laser pen 3-2. The shielding cavity 3-1 is a metal body. The center of one side of the shielding cavity 3-1 where the aiming laser pen 3-2 is installed is provided with a laser through hole, and the other side opposite to the aiming laser pen 3-2 is provided with a square hole, so that the metal filter 1-1 of the online proton imaging module 1 can be exposed.

[0050] The material of the shielding cavity 3-1 in the shielding aiming module 3 is selected from materials such as lead and tungsten which have high shielding effect on X-rays.

[0051] The online proton imaging ion spectrometer diagnostic system provided by the present application determines whether the online proton imaging module 1, the online Thomson ion spectrometer module 2, and the light beam of the aiming laser pen 3-2 are coaxially arranged through the aiming laser pen 3-2 of the shielding aiming assembly. If they are not coaxial, they are adjusted through the adjusting structure until they are coaxial.

[0052] The online proton imaging ion spectrometer diagnosis system provided by the application can realize simultaneous coaxial online measurement of proton imaging and ion energy spectrum, and provides more convenient and rapid diagnosis data for laser plasma ion acceleration diagnosis.

[0053] The working principle of the online proton imaging ion spectrometer diagnosis system is as follows:

[0054] The laser emitted by the aiming laser pen 3-2 is incident on the target surface (the target surface is located in front of the online proton imaging module 1 in the experiment, not shown in the figure) after passing through the online proton imaging module 1 from back to front.

[0055] Then, the aiming laser pen 3-2 is turned off. The formal experiment is started, the ultrastrong laser is focused to be incident on the target surface to accelerate to generate protons, heavy ions, electrons, X-rays, etc., which are first incident on the metal filter 1-1 of the online proton imaging module 1. The metal filter 1-1 can shield the interference of the target leakage laser and low-energy heavy ions on the proton imaging recording. The first scintillator 1-2 is thin enough (the thickness is in the order of 10 microns), mainly for proton energy deposition, that is, the spatial distribution information of the protons is converted into visible light, and then the visible light is transmitted to the first CMOS sensor through the first optical fiber panel 1-3 to realize light recording. The spatial distribution and intensity information of the recorded signal are used to reflect the spatial distribution information of the protons, that is, the online recording of proton imaging is realized. The electron and X-ray have strong penetration and will pass out from the back of the first scintillator 1-2 and be blocked by the front wall of the dipole magnet 2-2 of the online Thomson ion spectrometer module 2. The electron, X-ray, proton and heavy ion passing out from the center hole of the first scintillator 1-2 enter the dipole magnet 2-2 through the collimating hole 2-1 arranged in the middle of the front wall of the dipole magnet 2-2. The X-ray is transmitted along a straight line. The electron and ion (including proton and heavy ion) have different charged properties, the electron is deflected downward, and the ion is deflected upward, so as to realize separation. Then the ion enters the electrode plate 2-3 and is deflected left and right (depending on the voltage direction), and the deflection degree of different nuclear mass ratios is different. Thus, the separation of different types of ions is realized. Finally, different parabolic curves are recorded on the ion collection module of the online Thomson ion spectrometer module 2, and different energy and type of ions are incident on different positions on the surface of the second scintillator 2-7. The position of each ion incident on the surface of the second scintillator 2-7 is a parabola, and different positions of the parabola correspond to different ion energies, and different ions are different parabolas.

[0056] The ions incident on the second scintillator 2-7 will deposit energy and produce scintillation light. The scintillation light is transmitted through the second optical fiber panel 2-8 to the second CMOS sensor 2-9, and an electric signal is generated through the photoelectric effect. The electric signal is converted into a digital signal through analog-digital conversion, and the digital signal is transmitted to a computer through a data line for recording. The computer has an acquisition software with a two-dimensional pixel array of m*n. Each pixel corresponds to a position on the scintillator surface. Thus, the parabolic curve can be recorded.

[0057] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An online proton imaging ion spectrometer diagnostic system, characterized in that, It includes an online proton imaging module (1), an online Thomson ion spectrometer module (2), and a shielded aiming module (3); The shielded aiming module (3) includes a shielded cavity (3-1) and an aiming laser pointer (3-2). The aiming laser pointer (3-2) is installed at the rear end of the shielded cavity (3-1). A straight diagnostic path is arranged along the front-to-back direction at the central axis of the shielded cavity (3-1). Through holes are opened at the front and rear ends of the shielded cavity (3-1) along the straight diagnostic path. The online proton imaging module (1) and the online Thomson ion spectrometer module (2) are installed in the shielded cavity (3-1) and pass through the straight diagnostic path from front to back. The laser emission direction of the aiming laser pointer (3-2) is from back to front and coincides with the straight diagnostic path. The online proton imaging module (1) includes a metal filter (1-1), a first scintillator (1-2), and two proton imaging acquisition components; the metal filter (1-1) and the first scintillator (1-2) are arranged overlapping each other and facing the straight diagnostic path, and each has a through hole at its center that coincides with the straight diagnostic path; The proton imaging acquisition component includes a first optical fiber panel (1-3) and a first CMOS sensor (1-4). The first optical fiber panel (1-3) is inclined to the first scintillator (1-2). The first optical fiber panel (1-3) is a right-angled trapezoidal plate, and its inclined waist surface is attached to the rear surface of the first scintillator (1-2). The first CMOS sensor (1-4) is attached to the right-angled waist surface of the first optical fiber panel (1-3). The two first optical fiber panels (1-3) of the proton imaging acquisition components form a V-shaped structure with the V-groove facing backward, and the left and right sides of the V-groove are symmetrically distributed on the left and right sides of the straight diagnostic path. The online Thomson ion spectrometer module (2) includes an ion beam deflection mechanism and an ion spectrum diagnostic acquisition component. Along the direction away from the ion beam deflection mechanism, the ion spectrum diagnostic acquisition component includes a light-shielding aluminum film (2-6), a second scintillator (2-7), a second fiber optic panel (2-8), and a second CMOS sensor (2-9) arranged in sequence. The ion spectrum diagnostic acquisition component does not pass through the straight diagnostic path. Under the deflection action of the ion beam deflection mechanism, the ion beam that passes through the online proton imaging module (1) from front to back and is located in the straight diagnostic path can be deflected and directed towards the ion spectrum diagnostic acquisition component.

2. The online proton imaging ion spectrometer diagnostic system according to claim 1, characterized in that, The aiming laser pointer (3-2) is mounted at the rear end of the shielding cavity (3-1) via an adjustment bracket (3-3). The adjustment bracket (3-3) can adjust the angle of the laser emission direction of the aiming laser pointer (3-2) so that the laser emission direction of the aiming laser pointer (3-2) coincides with the straight diagnostic path.

3. The online proton imaging ion spectrometer diagnostic system according to claim 1, characterized in that, The metal filter (1-1) is composed of four square filter sheets of different thicknesses arranged in a grid pattern.

4. The online proton imaging ion spectrometer diagnostic system according to claim 1, characterized in that, The online proton imaging module (1) further includes an adjustment plate (1-5). The metal filter (1-1), the first scintillator (1-2), the first fiber optic panel (1-3), and the first CMOS sensor (1-4) are all mounted on the top surface of the adjustment plate (1-5). The adjustment plate (1-5) can be adjusted and moved in both the horizontal and vertical directions.

5. The online proton imaging ion spectrometer diagnostic system according to claim 1, characterized in that, The ion beam deflection mechanism includes a diode magnet (2-2), an electrode plate (2-3), a high-voltage connecting cable (2-5), and a miniature high-voltage power supply (2-4). The diode magnet (2-2) has a collimation hole (2-1) with a through-hole structure that coincides with the straight diagnostic path. The extension line of the central axis of the collimation hole (2-1) passes through the middle gap of the electrode plate (2-3). The ion spectrum diagnostic acquisition component faces the electrode plate (2-3) and is inclined to the straight diagnostic path.

6. The online proton imaging ion spectrometer diagnostic system according to claim 5, characterized in that, The electrode plate (2-3) includes two wedge-shaped copper plates symmetrically and parallelly distributed on the left and right sides of the straight diagnostic path; the wedge-shaped copper plates include four right-angled sides and one inclined side.

7. The online proton imaging ion spectrometer diagnostic system according to claim 1, characterized in that, The shielding cavity (3-1) is made of lead and / or tungsten.

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