Z pinch collapse stage charged particle collection device and method

Abstract

The invention provides a device and a method for collecting charged particles in a Z pinch collapse stage, relates to a device for collecting charged ions generated in a metal wire array pinch collapse stage, and aims to solve the problems that the charged particles generated in the existing Z pinch collapse stage are lack of effective shielding, irreversible damage is easily caused to an optical device, quantitative measurement of X rays is interfered, and the measurement accuracy is low. And the service life of the X-ray measuring device is severely influenced. The device adopts a segmented design and is divided into three parts, namely a collector, a gasket and end covers, the two end covers are respectively positioned on the upper and lower end faces of the collector, the gasket is arranged between the end covers and the collector, and the end covers and the collector are fixedly connected through bolts. The device is compact in structure, has the characteristics of miniaturization and detachability, can be fixed in a pinch device, and completes collection and measurement of charged particles in a vacuum environment. Therefore, the influence on an X-ray measuring device is avoided, and meanwhile, the interference on X-ray quantitative measurement is reduced.

Description

Technical Field

[0001] The invention relates to a device and method for collecting charged ions generated in a metal wire array pinch collapse stage, and in particular to a device and method for collecting charged particles in a Z pinch collapse stage. Background Art

[0002] Z-pinch technology can achieve high-efficiency conversion from pulse power driver electrical energy storage to X-ray radiation, and is also one of the technical approaches to achieve inertial confinement fusion. The Z-pinch implosion radiation process mainly goes through four stages, namely the explosion ionization stage, the implosion stage, the stagnation thermalization stage and the collapse stage. The radiation parameters and spatiotemporal distribution of X-rays generated during the implosion are key parameters for studying the physical process of the Z-pinch. However, in the collapse stage, the Z-pinch implosion instability develops, the magnetic pressure and thermal pressure are unbalanced, and the plasma scatters outward, generating a large number of charged particles, tiny load fragments and other splashing materials.

[0003] During the experiment, multiple diagnostic systems for measuring various physical data were installed around the target chamber. According to the diagnostic requirements, the X-ray streak camera must be installed near the target chamber and connected to the diagnostic window of the target chamber. At the same time, the cathode of the camera is facing the center of the target. This makes the photocathode and metal grid of the camera easily damaged by high-speed charged particles and explosion particles generated during the discharge process. If the charged particles in the splash are not effectively shielded, they will cause irreversible damage to the optical devices, which will not only interfere with the quantitative measurement of X-rays, but also seriously threaten the service life of the X-ray measurement device.

[0004] However, the types and velocity distribution of charged particles generated by wire array pinch are still unclear, and the characteristics of charged particles generated by the collapse of wire array pinch need to be studied urgently. In order to meet the needs of Z-pinch plasma research and measurement, extend the service life of measurement equipment, accurately measure X-ray yield, and study the characteristic parameters such as the types and velocity of charged particles in the collapse stage of wire array pinch, it is necessary to design an effective measurement and collection device to carry out research on the characteristics of charged particles in the collapse stage of Z-pinch. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problem that the charged particles generated in the existing Z pinch collapse stage lack effective shielding, which easily causes irreversible damage to optical devices, not only interferes with the quantitative measurement of X-rays, but also seriously affects the service life of the X-ray measuring device. A device and method for collecting charged particles in the Z pinch collapse stage are proposed.

[0006] To solve the above technical problems, the technical solutions provided by the present invention are as follows:

[0007] A Z-pinch collapse stage charged particle collection device, which is special in that it includes a collector, an end cap and a gasket;

[0008] The collector is provided with a deflection zone, which is a semicircular hollow portion surrounded by a semicircular edge and a diameter edge; holes are evenly distributed on the inner wall of the semicircular edge of the deflection zone for placing the Faraday cage; a collimation hole parallel to the diameter edge is provided at the junction of the semicircular edge and the diameter edge of the hollow portion;

[0009] The end caps are respectively mounted on the upper end surface and the lower end surface of the collector, and magnetic poles are respectively arranged on the sides where the end caps are connected to the collector, and the two magnetic poles are used to generate a uniform magnetic field in the deflection area;

[0010] A gasket is installed between the end cover and the collector, and a hollow area matching the magnetic pole is arranged on the gasket.

[0011] Furthermore, a concave avoidance zone is provided at the connection between the deflection zone and the collimation hole, and the avoidance zone is a rectangular groove or a circular groove.

[0012] Furthermore, the magnetic pole is a permanent magnet embedded in the side of the end cover; the end cover, gasket and collector are all made of ferromagnetic materials.

[0013] Furthermore, the center of the deflection zone is located on the central axis of the collector and close to one of the side edges perpendicular to the central axis of the collector.

[0014] Furthermore, a plurality of screw holes are evenly arranged around the circumference of the collector, the same screw holes are arranged at corresponding positions of the gasket and the end cover, and the end cover and the gasket are fixedly connected to the collector by bolts.

[0015] A Z-pinch collapse stage charged particle collection device, which is special in that it includes a collector, an end cap and a gasket;

[0016] The collector is provided with a deflection zone, which is a rectangular hollow portion; an end of one of the inner sides of the collector is provided with a collimating hole parallel to the inner side; holes are evenly distributed on the inner walls of the other three inner sides of the deflection zone for placing a Faraday cage;

[0017] The end caps are respectively mounted on the upper end surface and the lower end surface of the collector, and magnetic poles are respectively arranged on the sides where the end caps are connected to the collector, and the two magnetic poles are used to generate a uniform magnetic field in the deflection area;

[0018] A gasket is installed between the end cover and the collector, and a hollow area matching the magnetic pole is arranged on the gasket.

[0019] Furthermore, the magnetic pole is a permanent magnet embedded in the side of the end cover; the end cover, gasket and collector are all made of ferromagnetic materials.

[0020] Further, the center of the deflection zone coincides with the center of the collector.

[0021] Furthermore, a plurality of screw holes are evenly arranged around the circumference of the collector, the same screw holes are arranged at corresponding positions of the gasket and the end cover, and the end cover and the gasket are fixedly connected to the collector by bolts.

[0022] A method for collecting charged particles in a Z pinch collapse stage is based on a Z pinch collapse stage charged particle collection device, and the method is characterized in that the method comprises the following steps:

[0023] 1) The collimating hole screens the charged particles whose incident direction is perpendicular to the magnetic field and allows them to enter the collector;

[0024] 2) The charged particles enter different holes in a vertical direction through the deflection zone, and the Faraday cage in the hole collects the charged particles that enter the Faraday cage vertically;

[0025] 3) Measure the current in the Faraday cage;

[0026] 4) According to different pinch materials or different characteristics of charged particles, the magnetic induction intensity of the deflection zone is changed by changing the parameters of the magnetic poles and / or the thickness of the gasket, and steps 1-3 are repeated to collect new charged particles and obtain the measurement current.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The Z pinch collapse stage charged particle collection device of the present invention adopts a segmented design, which is divided into three parts: collector, gasket and end cover. The end cover is respectively located on the upper and lower end surfaces of the collector. The gasket is installed between the end cover and the collector and fixedly connected by bolts. The device has a compact structure, is miniaturized and detachable, and can be fixed inside the pinch device to complete the collection and measurement of charged particles in a vacuum environment. This avoids the impact on the X-ray measurement device and reduces the interference with the quantitative measurement of X-rays.

[0029] 2. The deflection zone of a Z-pinch collapse stage charged particle collection device of the present invention is designed to be semicircular, and the Faraday cage is installed on the holes on the inner wall of the deflection zone in a semicircular arrangement. The movement trajectory of the charged particles after entering the deflection zone from the collimating hole is tangent to the semicircular arc of the deflection zone. Therefore, when the distribution boundary of the Faraday cage is a semicircle, it can ensure that the charged particles are vertically incident into the Faraday cage, effectively improving the collection efficiency. The Faraday cage can also lead out a measurement wire to complete the connection between the collection device and other parts of the experimental system.

[0030] 3. The end cap and gasket of the Z pinch collapse stage charged particle collection device of the present invention are both detachable. For different pinch materials, the magnetic field size can be adjusted by replacing the magnetic pole parameters in the end cap magnetic pole; the distance between the magnetic pole and the collector can also be adjusted by changing the number of gaskets to achieve the purpose of adjusting the magnetic field size inside the device, thereby completing the collection and measurement of charged particles. Therefore, the device has good versatility and is suitable for different pinch materials and charged particles with different characteristics.

[0031] 4. The present invention uses ferromagnetic material as the main body of the device, which can confine the magnetic field to the collector, preventing the charged particles from being deflected by the magnetic field before entering the device, effectively improving the collection efficiency, and having a better collection effect on the charged particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic structural diagram of Embodiment 1 of the charged particle collection device in the Z pinch collapse stage of the present invention;

[0033] Figure 2 It is a cross-sectional view of Embodiment 1 of the charged particle collection device in the Z pinch collapse stage of the present invention;

[0034] Figure 3 It is a schematic diagram of the collector structure of Embodiment 1 of the charged particle collecting device in the Z pinch collapse stage of the present invention;

[0035] Figure 4 It is a schematic diagram of the collector structure of Embodiment 2 of the charged particle collection device in the Z pinch collapse stage of the present invention;

[0036] Explanation of the reference numerals: 1 - collector, 11 - deflection zone, 12 - avoidance zone; 2 - gasket; 3 - end cover, 31 - magnetic pole; 4 - hole; 5 - alignment hole; 6 - screw hole. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0038] Embodiment 1: The present invention proposes a device for collecting charged particles in the Z pinch collapse stage, such as Figure 1 As shown, the device adopts a segmented design, which is divided into a collector 1, a gasket 2 and two end covers 3, all of which are cubes with rectangular cross-sections and have matching sizes. The end covers 3 are made of ferromagnetic material and are connected to the upper and lower end surfaces of the collector 1 by bolts. Figure 2 As shown, the two end caps 3 are provided with magnetic poles 31 on the sides close to the collector 1. The two magnetic poles 31 are used to generate a magnetic field in the deflection area 11. The magnetic field is theoretically a uniform magnetic field. The magnetic induction intensity inside the device can be adjusted by changing the parameters or materials of the magnetic poles to be suitable for different pinch materials and charged particles with different characteristics.

[0039] The gasket 2 is installed between the end cap 3 and the collector 1. A hollow area matching the magnetic pole 31 is provided in the middle of the gasket 2 to facilitate the passage of the magnetic field. For different pinch materials and charged particles with different characteristics, in the actual assembly process, the distance between the magnetic pole and the collector 1 can be adjusted by changing the number or thickness of the gasket 2 to achieve the purpose of adjusting the magnetic field inside the device.

[0040] like Figure 3 As shown, the outer side of the collector 1 is provided with an iron shell, and the end caps 3 at the upper and lower ends of the collector 1 and the outer shell of the outer side together play the role of magnetic shielding to prevent the internal magnetic field from being disturbed by the outside world. The collector 1 is provided with a deflection area 11 and a hole 4. The deflection area 11 is a semicircular hollow portion surrounded by a semicircular edge and a diameter edge, and is located near one side of the collector 1. The center of the deflection area 11 is located on the central axis of the collector 1, and is close to one of the side edges perpendicular to the central axis of the collector 1. Holes 4 are evenly distributed on the inner wall of the semicircular edge of the deflection area 11 for placing the Faraday cage; collimation holes 5 are provided on the outer side of the collector 1, and the collimation holes 5 are located at the junction of the semicircular edge and one of the diameter edges of the hollow portion, and the collimation holes 5 are parallel to the diameter edge. Since there is a magnetic field inside the collimating hole 5, in order to prevent it from interfering with the uniform magnetic field in the collector 1, an avoidance zone 12 is provided at one end of the diameter side of the deflection zone 11 connected to the collimating hole 5. The avoidance zone 12 is a rectangular groove, and its length is set according to the magnetic field size and the characteristics of the measured charged particles. In this embodiment, the charged particles are aluminum ions, and the size of the avoidance zone is 10mm*40mm.

[0041] The collimating hole 5 can filter charged particles whose incident direction is perpendicular to the magnetic field. The motion trajectory of the charged particles entering the deflection area 11 through the collimating hole 5 is tangent to the semicircular arc of the deflection area 11. Since the Faraday cage is arranged in a semicircular manner on the inner wall of the deflection area 11, the charged particles can be vertically incident into the Faraday cage. The Faraday cage can collect charged particles efficiently, measure the charged particles at the same time, and lead out the measurement wire to complete the layout of the test system. The device as a whole uses ferromagnetism as the main material, the purpose is to confine the magnetic field to the device, prevent the charged particles from being deflected by the magnetic field before entering the device, and affect the collection effect.

[0042] A method for collecting charged particles in the Z pinch collapse phase comprises the following steps:

[0043] 1) The collimating hole 5 screens the charged particles whose incident direction is perpendicular to the magnetic field and allows them to enter the collector 1;

[0044] 2) The charged particles enter different holes 4 in a vertical direction through the deflection area 11, and the Faraday cage in the hole 4 collects the charged particles that enter the Faraday cage vertically;

[0045] 3) Measure the current in the Faraday cage;

[0046] 4) According to different pinch materials or different characteristics of charged particles, the magnetic induction intensity of the deflection area 11 is changed by changing the parameters of the magnetic pole 31 and / or the thickness of the gasket 2, and steps 1-3 are repeated to collect new charged particles and obtain the measurement current.

[0047] Example 2: Figure 4 As shown, a deflection zone 11 is provided in the middle of the collector 1, and the deflection zone 11 is a rectangular hollow portion; a collimation hole 5 parallel to the inner side is provided at the end of one of the inner sides of the collector 1; holes 4 are evenly distributed on the remaining inner walls of the deflection zone 11 for placing a Faraday cage; the center of the deflection zone 11 coincides with the center of the collector 1, and the rest of the structure is the same as in implementation 1.

[0048] The splashes generated in the Z pinch collapse stage are of many types and at high speeds, and the splashes are difficult to collect and measure. The present invention effectively solves the problem of collecting and measuring charged particles. The device has the characteristics of high collection efficiency, miniaturization and detachability, and can be fixed inside the pinch device to complete the collection and measurement of charged particles in a vacuum environment. In addition, for different pinch materials, the magnetic field size can be adjusted by adjusting the magnetic pole parameters and the thickness of the gasket 2 to complete the collection and measurement of charged particles.

Claims

1. A Z-pinch collapse stage charged particle collection device, characterized in that: It comprises a collector (1), an end cover (3) and a gasket (2); The collector (1) is provided with a deflection zone (11), which is a semicircular hollow portion surrounded by a semicircular edge and a diameter edge; holes (4) are evenly distributed on the inner wall of the semicircular edge of the deflection zone (11) for placing a Faraday cage; a collimating hole (5) parallel to the diameter edge is provided at a junction between the semicircular edge and the diameter edge of the hollow portion; The end caps (3) are respectively mounted on the upper end surface and the lower end surface of the collector (1); magnetic poles (31) are respectively provided on the side surfaces where the end caps (3) and the collector (1) are connected; the two magnetic poles (31) are used to generate a uniform magnetic field in the deflection area (11); A gasket (2) is installed between the end cover (3) and the collector (1), and a hollow area matching the magnetic pole (31) is provided on the gasket (2).

2. The Z-pinch collapse stage charged particle collection device according to claim 1, characterized in that: A concave avoidance zone (12) is provided at the connection between the deflection zone (11) and the collimation hole (5), and the avoidance zone (12) is a rectangular groove or a circular groove.

3. The Z-pinch collapse stage charged particle collection device according to claim 1 or 2, characterized in that: The magnetic pole (31) is a permanent magnet embedded in the side of the end cover; the end cover (3), the gasket (2) and the collector (1) are all made of ferromagnetic materials.

4. The Z-pinch collapse stage charged particle collection device according to claim 3, characterized in that: The center of the deflection zone (11) is located on the central axis of the collector (1) and is close to one of the side edges perpendicular to the central axis of the collector (1).

5. The Z-pinch collapse stage charged particle collection device according to claim 4, characterized in that: The collector (1) is evenly provided with a plurality of screw holes (6) in the circumferential direction, the gasket (2) and the end cover (3) are provided with the same screw holes (6) at corresponding positions, and the end cover (3) and the gasket (2) are fixedly connected to the collector (1) by bolts.

6. A Z-pinch collapse stage charged particle collection device, characterized in that: It comprises a collector (1), an end cover (3) and a gasket (2); The collector (1) is provided with a deflection area (11), which is a rectangular hollow portion; an end portion of one inner side edge of the collector (1) is provided with a collimating hole (5) parallel to the inner side edge; holes (4) are evenly distributed on the inner walls of the other three inner sides of the deflection area (11) for placing a Faraday cage; The end caps (3) are respectively mounted on the upper end surface and the lower end surface of the collector (1); magnetic poles (31) are respectively provided on the side surfaces where the end caps (3) and the collector (1) are connected; the two magnetic poles (31) are used to generate a uniform magnetic field in the deflection area (11); A gasket (2) is installed between the end cover (3) and the collector (1), and a hollow area matching the magnetic pole (31) is provided on the gasket (2).

7. The Z-pinch collapse stage charged particle collection device according to claim 6, characterized in that: The magnetic pole (31) is a permanent magnet embedded in the side of the end cover; the end cover (3), the gasket (2) and the collector (1) are all made of ferromagnetic materials.

8. The Z-pinch collapse stage charged particle collection device according to claim 7, characterized in that: The center of the deflection zone (11) coincides with the center of the collector (1).

9. The Z-pinch collapse stage charged particle collection device according to claim 8, characterized in that: The collector (1) is evenly provided with a plurality of screw holes (6) in the circumferential direction, the gasket (2) and the end cover (3) are provided with the same screw holes (6) at corresponding positions, and the end cover (3) and the gasket (2) are fixedly connected to the collector (1) by bolts.

10. A method for collecting charged particles in the Z pinch collapse stage, based on the Z pinch collapse stage charged particle collection device according to any one of claims 1 to 9, characterized in that: The following steps are involved: 1) The collimating hole (5) screens the charged particles whose incident direction is perpendicular to the magnetic field and allows them to enter the collector (1); 2) the charged particles enter different holes (4) in a vertical direction through the deflection area (11), and the Faraday cage in the hole (4) collects the charged particles that enter the Faraday cage vertically; 3) Measure the current in the Faraday cage; 4) According to different pinch materials or different characteristics of charged particles, the magnetic induction intensity of the deflection area (11) is changed by changing the parameters of the magnetic pole (31) and / or the thickness of the gasket (2), and steps 1-3 are repeated to collect new charged particles and obtain the measurement current.

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