A neutral particle analysis system with both mass and energy resolution capabilities

Abstract

The present invention belongs to the field of high temperature plasma diagnosis, and specifically relates to a neutral particle analysis system with both mass and energy resolution capabilities, including a stripping chamber, an analysis module and a detector array, wherein the stripping chamber uses gas stripping, the analysis module uses magnetic field analysis, and the detector array uses a semiconductor detector with energy resolution capabilities; the neutral particle analysis system of the present invention for measuring the mass and energy of neutral particles in fusion plasma, compared with the method of combining electrostatic field with magnetic field analysis in traditional neutral particle analyzers, uses a magnetic field combined with a semiconductor detector with energy spectrum measurement capabilities. Momentum analysis is performed through a magnetic field, and energy analysis is performed through pulse amplitude analysis, without the need to use an electrostatic deflection system, thereby reducing the size of the analysis module and the complexity of the system.

Description

Technical Field

[0001] The invention belongs to the field of high temperature plasma diagnosis, and in particular relates to a neutral particle analysis system with both mass and energy resolution capabilities. Background Art

[0002] In magnetic confinement fusion high-temperature plasma, the neutral particles generated by the resonant charge exchange reaction between ions and neutral particles (such as H atoms) have almost the same energy as the reacting ions. Neutral particles have no charge, and their flight trajectory is not affected by the magnetic field. There is a certain probability that they will escape from the plasma before the next collision. Detecting the neutral particles generated by the reaction and escaping from the plasma can analyze the density information of ions and neutral particles inside the plasma. The diagnostic tool that specifically measures the energy spectrum of this neutral particle is called a neutral particle analyzer (NPA).

[0003] In the field of magnetic confinement fusion plasma research, NPA is a key diagnostic tool for high-energy ion physics analysis, ion temperature measurement, neutral particle density measurement, and fusion reactor fuel density ratio (T / D) measurement. In the design of traditional NPA, in order to achieve energy analysis, a strong electrostatic field is generally used to deflect ions; in order to achieve both mass and energy analysis, a strong magnetic field combined with a strong electrostatic field is generally used to deflect ions, and the detection part generally places electron multipliers on different deflection orbits for counting measurements. Summary of the invention

[0004] The purpose of the present invention is to provide a neutral particle analysis system with both mass and energy resolution capabilities in view of the above-mentioned defects in the prior art, which can diagnose neutral particles in high-temperature plasma and has both mass and energy resolution capabilities.

[0005] The technical solution of the present invention is as follows:

[0006] A neutral particle analysis system with both mass and energy resolution capabilities, comprising a stripping chamber, an analysis module and a detector array, wherein the stripping chamber uses gas stripping, the analysis module uses magnetic field analysis, and the detector array uses semiconductor detectors with energy resolution capabilities;

[0007] The detector array is fixed on the main vacuum wall and distributed on different deflection routes, with the detector entrance apertures aligned with the analysis magnet slits;

[0008] The magnet is fixed on the wall of the main vacuum chamber, and the two poles of the magnet are planar structures with a thin gap between them to ensure that the strength of the magnetic field is sufficient and the ions can pass smoothly;

[0009] The box body is fixed to the wall of the main vacuum chamber 7;

[0010] The main vacuum chamber is connected to the vacuum chamber of the fusion device through a straight pipe, the lower opening of the main vacuum chamber is connected to the exhaust system, the first alignment baffle and the second alignment baffle are fixed on the wall of the main vacuum chamber, the first alignment baffle is located between the device connecting straight pipe and the stripping chamber, and the second alignment baffle is located between the stripping chamber and the magnet.

[0011] A neutral particle analysis system with both mass and energy resolution capabilities. The detector signal achieves energy resolution and number statistics through pulse height analysis, and achieves mass and energy resolution simultaneously through momentum analysis of the magnetic field combined with the detector's energy resolution.

[0012] A neutral particle analysis system with both mass and energy resolution capabilities, the stripping chamber comprises a box body and two straight tubes, the two straight tubes are respectively welded on the front and rear surfaces of the box body, and the central axis of the two straight tubes coincides with the central axis of the connecting pipeline of the main vacuum chamber fusion device.

[0013] A neutral particle analysis system with both mass and energy resolution capabilities, wherein the box body is a hollow cavity and is preferably made of 304 stainless steel.

[0014] A neutral particle analysis system with both mass and energy resolution capabilities, wherein the analysis module comprises a magnet, which is an electromagnet or a permanent magnet.

[0015] A neutral particle analysis system with both mass and energy resolution capabilities, wherein the detector array preferably uses semiconductor detectors.

[0016] A neutral particle analysis system with both mass and energy resolution capabilities, wherein the main vacuum chamber is preferably made of 304 stainless steel.

[0017] A neutral particle analysis system with both mass and energy resolution capabilities, wherein a first collimating baffle and a second collimating baffle are both provided with small holes with a diameter of about 2 mm on the central axis of a straight tube connected to the device.

[0018] The beneficial effects of the present invention are:

[0019] Compared with the conventional neutral particle analyzer which adopts the method of combining electrostatic field with magnetic field analysis, the neutral particle analysis system of the present invention for measuring the mass and energy of neutral particles in fusion plasma adopts the method of combining magnetic field with magnetic field analysis and adopts the method of combining magnetic field with semiconductor detector having energy spectrum measurement capability.

[0020] Momentum analysis is performed through magnetic field, and energy analysis is performed through pulse amplitude analysis. There is no need to use an electrostatic deflection system, which reduces the size of the analysis module and the complexity of the system.

[0021] Generally speaking, the main neutral particle components in fusion plasma are H, D, T and He. The analysis magnet makes particles with equal momentum have the same deflection position and are collected by the same detector.

[0022] Under the condition of equal momentum, the energy ratio of H, D, T and He is 12:6:4:3.

[0023] The pulse amplitude analysis method can distinguish such large differences in energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a neutral particle analysis system for measuring energy and momentum of neutral particles in fusion plasma according to the present invention;

[0025] 1-first collimating baffle; 2-box body; 3-straight tube; 4-second collimating baffle; 5-magnet; 6-detector array; 7-main vacuum chamber; 8-shielding structure. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] The neutral particle analysis system for measuring the mass and momentum of neutral particles in fusion plasma of the present invention mainly comprises: a stripping chamber, an analysis module and a detector array 6. The stripping chamber adopts gas stripping, the analysis module adopts magnetic field analysis, and the detector array 6 adopts a semiconductor detector with energy resolution capability.

[0028] The detector array 6 is fixed on the wall of the main vacuum chamber 7 and distributed on different deflection routes, and the detector entrance holes are aligned with the analysis magnet slits.

[0029] The magnet 5 is fixed to the wall of the main vacuum chamber 7. The two poles of the magnet 5 are planar structures with a thin gap between them to ensure that the strength of the magnetic field is sufficient and the ions can pass smoothly.

[0030] The main vacuum chamber 7 is connected to the fusion device vacuum chamber through a straight pipe. The lower opening of the main vacuum chamber 7 is connected to the exhaust system.

[0031] The first alignment baffle 1 and the second alignment baffle 4 are fixed on the wall of the main vacuum chamber. The first alignment baffle 1 is located between the device connecting straight tube 3 and the stripping chamber, and the second alignment baffle 4 is located between the stripping chamber and the magnet 5.

[0032] The detector signal can achieve energy resolution and number counting through pulse height analysis. The momentum analysis of the magnetic field combined with the energy resolution of the detector can achieve both mass and energy resolution.

[0033] The stripping chamber comprises a box body 2 and two straight tubes 3, the two straight tubes 3 are welded on the front and rear surfaces of the box body 2 respectively, and the central axis of the two straight tubes 3 coincides with the central axis of the connecting pipe of the main vacuum chamber 7 fusion device.

[0034] The box body 2 is fixed to the wall of the main vacuum chamber 7 .

[0035] The box body 2 is a hollow cavity, and is preferably made of 304 stainless steel.

[0036] The analysis module comprises a magnet 5 which is an electromagnet or a permanent magnet.

[0037] The detector array 6 preferably uses semiconductor detectors.

[0038] The main vacuum chamber 7 is preferably made of 304 stainless steel.

[0039] The first collimating baffle 1 and the second collimating baffle 4 are both provided with small holes with a diameter of about 2 mm on the central axis of the device connecting straight tube.

Claims

1. A neutral particle analysis system with both mass and energy resolution capabilities, comprising a stripping chamber, an analysis module and a detector array, wherein the stripping chamber uses gas stripping, the analysis module uses magnetic field analysis, and the detector array uses semiconductor detectors with energy resolution capabilities; Features: The detector array is fixed on the wall of the main vacuum chamber and distributed on different deflection routes, and the detector entrance holes are aligned with the analysis magnet slits; The magnet is fixed on the wall of the main vacuum chamber, and the two poles of the magnet are planar structures with a thin gap between them to ensure that the strength of the magnetic field is sufficient and the ions can pass smoothly; The box body is fixed to the wall of the main vacuum chamber; The main vacuum chamber is connected to the vacuum chamber of the fusion device through a straight pipe, the lower opening of the main vacuum chamber is connected to the exhaust system, the first alignment baffle and the second alignment baffle are fixed on the wall of the main vacuum chamber, the first alignment baffle is located between the device connecting straight pipe and the stripping chamber, and the second alignment baffle is located between the stripping chamber and the magnet; The stripping chamber comprises a box body and two straight tubes, the two straight tubes are respectively welded on the front and rear surfaces of the box body, and the central axis of the two straight tubes coincides with the central axis of the connecting pipe of the main vacuum chamber fusion device; The analysis module includes a magnet, which is an electromagnet or a permanent magnet.

2. A neutral particle analysis system with both mass and energy resolution capabilities as claimed in claim 1, characterized in that: The detector signal is energy resolved and counted through pulse height analysis, and mass and energy resolution are achieved simultaneously through momentum analysis of the magnetic field combined with the energy resolution of the detector.

3. A neutral particle analysis system with both mass and energy resolution capabilities as claimed in claim 1, characterized in that: The box body is a hollow cavity and is made of 304 stainless steel.

4. A neutral particle analysis system with both mass and energy resolution capabilities as claimed in claim 1, characterized in that: The detector array uses semiconductor detectors.

5. A neutral particle analysis system with both mass and energy resolution capabilities as claimed in claim 1, characterized in that: The main vacuum chamber is made of 304 stainless steel.

6. A neutral particle analysis system with both mass and energy resolution capabilities as claimed in claim 1, characterized in that: The first collimating baffle and the second collimating baffle are both provided with small holes with a diameter of about 2 mm on the central axis of the device connecting straight tube.

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