Single-energy X-ray radiation device based on Si single crystal diffraction and generation method

Abstract

The invention relates to a single-energy X-ray radiation device based on Si single crystal diffraction and a generation method, belongs to the technical field of space optics, and solves the technical problems that an existing single-energy radiation source is single in energy point and complex in device structure. The single-energy X-ray radiation device comprises an X-ray source, a first slit regulator, a second slit regulator, a third slit regulator, a fourth slit regulator, an X-ray detector, a lower rotary table, an upper rotary table, a sample placing table, an X-ray source guide rail, a detector guide rail, an optical platform, a Si single crystal, an X-ray source placing table, an expansion table and a support. The single-energy X-ray generation method comprises the steps of installing the Si single crystal, setting the angle range and the rotation step length of the lower rotary table and the upper rotary table, and testing the X-ray energy spectrum. The device is used for generating single-energy X-rays and calibrating the X-ray detector on the ground.

Description

Technical Field

[0001] The present invention belongs to the field of space optics technology, and in particular relates to a monoenergetic X-ray radiation device based on Si single crystal diffraction and a generation method thereof. Background Art

[0002] In recent years, X-ray astronomical observation has entered a period of vigorous development. A large number of X-ray astronomical satellites with complex structures and superior performance have been successfully launched, greatly broadening the scope of observation and data quality. During this period, representative satellite missions in the world include: ROSAT, ASCA, RXTE, CXO, XMM-Newton, Swift, etc. my country also successfully launched the "Insight" satellite and the "Einstein Probe" (EP) in June 2017 and January 2024, respectively. The enhanced X-ray Timing and Polarization (eXTP) satellite is also in the project establishment stage. This series of satellites are equipped with different types of X-ray detectors. The performance indicators of the detectors, such as energy spectrum response and energy resolution, directly determine the accuracy of space X-ray observations. Therefore, it is very necessary to conduct ground calibration tests of X-ray detectors. As the core component of the ground calibration system, the key technology breakthrough and successful development of the monoenergetic X-ray source are crucial.

[0003] Monoenergetic radiation sources that meet the requirements generally include radioisotope sources, synchrotron radiation sources, Bragg diffraction monoenergetic radiation sources, and K fluorescence radiation sources. The Bragg diffraction monoenergetic radiation source obtains the required monoenergetic X-rays through crystal Bragg diffraction. The device has a low manufacturing cost, is easy to implement, and has good controllability. Compared with radioisotope sources, it is more accurate in the energy calibration of detectors, safer to use, and easier to manage; compared with synchrotron radiation sources, the device has low maintenance costs and is easy to control; compared with K fluorescence radiation sources, the energy can be continuously adjusted by adjusting the crystal angle, which can meet the calibration conditions of different types of detectors. Summary of the invention

[0004] In order to overcome the shortcomings of the existing monoenergetic radiation source, such as single energy point and complex device structure, the present invention proposes a monoenergetic X-ray radiation device and a generation method based on Si single crystal diffraction.

[0005] The technical solution adopted by the present invention to solve the technical problem is:

[0006] A monoenergetic X-ray radiation device based on Si single crystal diffraction comprises an X-ray source, a first slit adjuster, a second slit adjuster, a third slit adjuster, a fourth slit adjuster, an X-ray detector, a lower turntable, an upper turntable, a sample placement table, an X-ray source guide rail, a detector guide rail, an optical platform, a Si single crystal, an X-ray source placement table, an extension table, and a bracket.

[0007] The first slit adjuster and the third slit adjuster are provided with horizontal slits, and the second slit adjuster and the fourth slit adjuster are provided with vertical slits. The slit widths of the horizontal slits and the vertical slits are adjustable, and the horizontal slits and the vertical slits are used to limit the beam size and collimate the optical path.

[0008] The X-ray source generates continuous spectrum X-rays, which pass through the first slit adjuster and the second slit adjuster in sequence, are reflected by the Si single crystal, and the reflected light beam passes through the third slit adjuster and the fourth slit adjuster in sequence before being emitted. The X-ray detector detects the X-rays emitted by the fourth slit adjuster.

[0009] The X-ray source is located on an X-ray source rail, and the X-ray source can move along the X-ray source rail. The X-ray source rail, the first slit adjuster, and the second slit adjuster are located on an X-ray source placement table, and the X-ray source placement table is fixed on the optical platform through a bracket.

[0010] The Si single crystal is mounted on a sample placement table, which is located on an upper turntable. The upper turntable can rotate along an axis perpendicular to a horizontal plane.

[0011] The X-ray detector is placed on a detector guide rail, and the X-ray detector can move along the detector guide rail.

[0012] The upper turntable, the third slit adjuster, the fourth slit adjuster, and the detector guide rail are fixed on the extension table, and the extension table is fixed on the lower turntable. Both the lower turntable and the upper turntable are electric turntables. The center line of the lower turntable's shaft coincides with the center line of the upper turntable's shaft. The lower turntable is installed on the optical platform.

[0013] In the above-mentioned single-energy X-ray radiation device, the slit widths of the horizontal slit and the vertical slit are 0.05 mm to 5 mm, and the slit lengths of the horizontal slit and the vertical slit are both 100 mm.

[0014] In the above-mentioned single-energy X-ray radiation device, the target material of the X-ray source is one of W target, Mo target, and Cu target, the maximum tube voltage of the X-ray source is 50 kV, the maximum tube current is 1 mA, and the focal spot size is 1 mm×1 mm.

[0015] In the above-mentioned single-energy X-ray radiation device, the target material of the X-ray source is a W target, the tube voltage is set to 8 kV, and the tube current is set to 0.8 mA.

[0016] In the above-mentioned single-energy X-ray radiation device, the Si single crystal is one of Si(220), Si(311), Si(400), Si(331), and Si(224).

[0017] In the above-mentioned single-energy X-ray radiation device, the lower turntable and the upper turntable are both electric turntables, and the angle rotation accuracy is 0.01°.

[0018] In the above-mentioned single-energy X-ray radiation device, the X-ray detector is one of a silicon drift detector, a CdZnTe detector, and a high-purity germanium detector, with a response energy range of 1keV to 100keV, an energy resolution of <5%, and a detection efficiency of >80%.

[0019] A method for generating monoenergetic X-rays based on Si single crystal diffraction comprises the following steps:

[0020] Step 1: Install Si single crystal

[0021] Set up X-ray detector and Si single crystal.

[0022] The set X-ray detector is mounted on the detector rail, and the set Si single crystal is mounted on the sample placement table.

[0023] Step 2: Set the angle range and rotation step of the lower and upper turntables

[0024] Set the rotation angle range and rotation step of the lower turntable, and the rotation angle range and rotation step of the upper turntable.

[0025] The relationship between the lower turntable rotation angle α1 and the upper turntable rotation angle α2 is:

[0026] α1=-2α2

[0027] A positive rotation angle α1 of the lower turntable or a positive rotation angle α2 of the upper turntable indicates a clockwise direction; a negative rotation angle α1 of the lower turntable or a negative rotation angle α2 of the upper turntable indicates a counterclockwise direction.

[0028] Step 3: Test the X-ray spectrum

[0029] Start the X-ray source, X-ray detector, lower turntable and upper turntable.

[0030] According to the set rotation angle range and rotation step of the lower turntable and the upper turntable, the lower turntable and the upper turntable are rotated, and the X-ray energy spectrum is tested once with the X-ray detector every time the lower turntable and the upper turntable rotate one step.

[0031] In the above-mentioned monoenergetic X-ray generation method, the Si single crystal is set to Si(400), and the X-ray detector is set to a silicon drift detector.

[0032] The rotation angle of the lower turntable is 84°~98°, the step length is 0.2°, and the direction is clockwise; the rotation angle of the upper turntable is -42°~-49°, the step length is -0.1°, and the direction is counterclockwise; for each step, the X-ray energy spectrum is tested once with a silicon drift detector, and the integration time is 60s.

[0033] In the above-mentioned monoenergetic X-ray generation method, the Si single crystal is set to Si(311), and the X-ray detector is set to a silicon drift detector.

[0034] The rotation angle of the lower turntable is 84°~92°, the step length is 1°, and the direction is clockwise; the rotation angle of the upper turntable is -42°~-46°, the step length is -0.5°, and the direction is counterclockwise. For each step, the X-ray energy spectrum is tested once with the silicon drift detector, and the integration time is 60s.

[0035] The beneficial effects of the present invention are:

[0036] A monoenergetic X-ray radiation device based on Si single crystal diffraction utilizes a first slit adjuster, a second slit adjuster, a third slit adjuster and a fourth slit adjuster to limit the beam size and collimate the optical path, thereby reducing the solid angle of the X-ray emitted by the X-ray source, avoiding the broadening of the diffracted X-ray energy spectrum caused by the poor diffraction angle resolution when the continuous spectrum X-ray reaches the Si single crystal, and significantly improving the monochromaticity of the X-ray.

[0037] A monoenergetic X-ray radiation device based on Si single crystal diffraction utilizes the lower turntable and the upper turntable to adjust the diffraction angle of the Si single crystal and matches Si single crystals with different crystal orientations. It can realize continuous adjustment of the monoenergetic X-ray energy with an adjustment accuracy of 10eV, which meets the ground calibration requirements of X-ray detectors in different energy ranges and is very practical.

[0038] A mono-energy X-ray radiation device based on Si single crystal diffraction uses a lower turntable and an upper turntable to adjust the rotation angle of the X-ray detector and the Si single crystal, and satisfies the double angle relationship through program control, which significantly improves the efficiency of ground calibration of X-ray detectors using the mono-energy X-ray radiation device. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic structural diagram of a monoenergetic X-ray radiation device based on Si single crystal diffraction according to the present invention;

[0040] Figure 2 This is a schematic diagram of the optical path of the monoenergetic X-ray radiation device based on Si single crystal diffraction of the present invention;

[0041] Figure 3 The X-ray energy spectra at different diffraction angles of Example 1 of the present invention;

[0042] Figure 4This is a graph showing the change in the peak position of the Bragg diffraction peak with the diffraction angle when the diffraction angle step is 0.5° in Example 1 of the present invention;

[0043] Figure 5 is a graph showing the change in the peak position of the Bragg diffraction peak with the diffraction angle at a diffraction angle step of 0.1° in Example 1 of the present invention;

[0044] Figure 6 This is a graph showing the change in the peak position of the Bragg diffraction peak with the diffraction angle when the diffraction angle step is 0.5° in Example 2 of the present invention.

[0045] Figure numerals: 1. X-ray source, 2. 1st slit adjuster, 3. 2nd slit adjuster, 4. 3rd slit adjuster, 5. 4th slit adjuster, 6. X-ray detector, 7. Lower turntable, 8. Upper turntable, 9. Sample placement table, 10. X-ray source guide rail, 11. Detector guide rail, 12. Optical platform, 13. Si single crystal, 14. X-ray source placement table, 15. Extension table, 16. Bracket. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] A monoenergetic X-ray radiation device based on Si single crystal diffraction, such as Figure 1 As shown, it includes an X-ray source 1, a first slit adjuster 2, a second slit adjuster 3, a third slit adjuster 4, a fourth slit adjuster 5, an X-ray detector 6, a lower turntable 7, an upper turntable 8, a sample placement table 9, an X-ray source guide rail 10, a detector guide rail 11, an optical platform 12, a Si single crystal 13, an X-ray source placement table 14, an extension table 15, and a bracket 16; the X-ray source 1 is used to generate continuous spectrum X-rays; the first slit adjuster 2, the second slit adjuster 3, the third slit adjuster 4, the ... The regulator 4 and the fourth slit adjuster 5 are used to limit the beam size and collimate the optical path; the X-ray detector 6 is used to record the number of X-ray photons; the lower turntable 7 and the upper turntable 8 are used to adjust the rotation angle of the X-ray detector 6 and the sample placement table 9; the sample placement table 9 is used to place the Si single crystal 13; the X-ray source guide rail 10 and the detector guide rail 11 are used to adjust the position of the X-ray source 1 and the X-ray detector 6; the optical platform 12 is used to fix the above-mentioned devices; the Si single crystal 13 is used to diffract and produce monoenergetic X-rays.

[0048] The optical path of the X-rays emitted from the X-ray source 1 to the X-ray detector 6 is as follows: Figure 2 shown.

[0049] The target material of the X-ray source 1 includes but is not limited to W target, Mo target, Cu target, the maximum tube voltage is 50 kV, the maximum tube current is 1 mA, and the focal spot size is 1 mm×1 mm. For example, the target material of the X-ray source 1 is W target, the tube voltage is set to 8 kV, and the tube current is set to 0.8 mA.

[0050] The first slit adjuster 2 and the third slit adjuster 4 are provided with horizontal slits, and the second slit adjuster 3 and the fourth slit adjuster 5 are provided with vertical slits. The slit widths of the horizontal and vertical slits are both in the range of 0.05 mm to 5 mm. For example, the slit width is 2 mm and the slit length is 100 mm.

[0051] The X-ray detector 6 includes but is not limited to a silicon drift detector, a CdZnTe detector, and a high-purity germanium detector, with a response energy range covering 1 keV to 100 keV, an energy resolution of <5%, and a detection efficiency of >80%.

[0052] For example, the X-ray detector 6 is a silicon drift detector, with a response energy range covering 1 keV to 33 keV, an energy resolution of <3%, and a detection efficiency of >80%.

[0053] The lower turntable 7 and the upper turntable 8 are both electric turntables, which are rotated by program control, and the center line of the rotation axis of the lower turntable 7 coincides with the center line of the rotation axis of the upper turntable 8.

[0054] The rotation angle of the lower turntable 7 is α1, and the rotation angle of the upper turntable 8 is α2, and the two form a double angle relationship, that is, α1=-2α2; the rotation angle α1 of the lower turntable 7 is positive, indicating a clockwise direction, and the rotation angle α2 of the upper turntable 8 is negative, indicating a counterclockwise direction, and the size of the rotation angle α2 corresponds to the diffraction angle of the Si single crystal; the angular rotation accuracy of the lower turntable 7 and the upper turntable 8 is 0.01°.

[0055] The Si single crystal 13 includes, but is not limited to, Si(220), Si(311), Si(400), Si(331), and Si(224).

[0056] A method for generating monoenergetic X-rays using a monoenergetic X-ray radiation device based on Si single crystal diffraction, the specific steps are as follows:

[0057] Step 1: Install Si single crystal

[0058] An X-ray detector 6 and a Si single crystal 13 are provided.

[0059] The set X-ray detector 6 is mounted on the detector rail 11 , and the set Si single crystal 13 is mounted on the sample placement table 9 .

[0060] Step 2: Set the angle range and rotation step length of the lower turntable 7 and the upper turntable 8

[0061] Set the rotation angle range and rotation step of the lower turntable 7, and the rotation angle range and rotation step of the upper turntable 8.

[0062] The relationship between the rotation angle α1 of the lower turntable 7 and the rotation angle α2 of the upper turntable 8 is:

[0063] α1=-2α2

[0064] The rotation angle α1 of the lower turntable 7 or the rotation angle α2 of the upper turntable 8 is positive, indicating a clockwise direction; the rotation angle α1 of the lower turntable 7 or the rotation angle α2 of the upper turntable 8 is negative, indicating a counterclockwise direction;

[0065] Step 3: Test the X-ray spectrum

[0066] The X-ray source 1 , the X-ray detector 6 , the lower turntable 7 and the upper turntable 8 are started.

[0067] According to the set rotation angle range and rotation step of the lower turntable 7 and the upper turntable 8, the lower turntable 7 and the upper turntable 8 are rotated, and the X-ray energy spectrum is tested once by the X-ray detector 6 every time the lower turntable 7 and the upper turntable 8 rotate one step.

[0068] Example 1

[0069] This embodiment is described by a monoenergetic X-ray radiation device based on Si single crystal diffraction, as follows:

[0070] As the Si single crystal 13 , Si (400) is selected.

[0071] The rotation angle of the lower turntable 7 is 84°~98°, the step length is 0.2°, and the direction is clockwise; the rotation angle of the upper turntable 8 is -42°~-49°, the step length is -0.1°, and the direction is counterclockwise; the corresponding diffraction angle of Si(400) single crystal is 42°~49°, the step length is 0.1°. For each rotation step, the X-ray energy spectrum is tested once with the silicon drift detector, and the integration time is 60s.

[0072] The X-ray energy spectrum at different diffraction angles, the change of the peak position of the Bragg diffraction peak with the diffraction angle at a diffraction angle step of 0.5°, and the change of the peak position of the Bragg diffraction peak with the diffraction angle at a diffraction angle step of 0.1° are shown in Figures 1 and 2. Figure 3 , Figure 4 and Figure 5 The single-energy X-ray covers the energy range of 6.20keV to 6.96keV and is continuously adjustable with an adjustment accuracy of 10eV.

[0073] Example 2

[0074] This embodiment is described by a monoenergetic X-ray radiation device based on Si single crystal diffraction, as follows:

[0075] As the Si single crystal 13 , Si(311) is selected.

[0076] The rotation angle of the lower turntable 7 is 84°~92°, the step length is 1°, and the direction is clockwise; the rotation angle of the upper turntable 8 is -42°~-46°, the step length is -0.5°, and the direction is counterclockwise; the corresponding diffraction angle of Si(311) single crystal is 42°~46°, the step length is 0.5°. For each rotation step, the X-ray energy spectrum is tested once with the silicon drift detector, and the integration time is 60s.

[0077] The change of Bragg diffraction peak position with diffraction angle at 0.5° diffraction angle step is shown in the figure Figure 6 The single-energy X-ray covers the energy range of 5.42keV to 5.83keV and is continuously adjustable.

[0078] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make modifications and changes according to the technical solution of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments on the existing basis according to the technical essence of the present invention should be within the scope of protection determined by the claims.

Claims

1. A monoenergetic X-ray radiation device based on Si single crystal diffraction, characterized in that: It comprises an X-ray source (1), a first slit adjuster (2), a second slit adjuster (3), a third slit adjuster (4), a fourth slit adjuster (5), an X-ray detector (6), a lower turntable (7), an upper turntable (8), a sample placement table (9), an X-ray source guide rail (10), a detector guide rail (11), an optical platform (12), a Si single crystal (13), an X-ray source placement table (14), an expansion table (15), and a bracket (16); The first slit adjuster (2) and the third slit adjuster (4) are provided with horizontal slits, and the second slit adjuster (3) and the fourth slit adjuster (5) are provided with vertical slits; the slit widths of the horizontal slits and the slit widths of the vertical slits are both adjustable, and the horizontal slits and the vertical slits are used to limit the beam size and collimate the optical path; The X-ray source (1) generates continuous spectrum X-rays, the generated X-rays sequentially pass through the first slit adjuster (2) and the second slit adjuster (3), are reflected by the Si single crystal (13), the reflected light beam sequentially passes through the third slit adjuster (4) and the fourth slit adjuster (5) before being emitted, and the X-ray detector (6) detects the X-rays emitted by the fourth slit adjuster (5); The X-ray source (1) is located on an X-ray source guide rail (10), and the X-ray source (1) can move along the X-ray source guide rail (10). The X-ray source guide rail (10), the first slit adjuster (2), and the second slit adjuster (3) are located on an X-ray source placement table (14), and the X-ray source placement table (14) is fixed on the optical platform (12) via a bracket (16); The Si single crystal (13) is mounted on a sample placement table (9), the sample placement table (9) is located on an upper turntable (8), and the upper turntable (8) can rotate along an axis perpendicular to a horizontal plane; The X-ray detector (6) is placed on a detector guide rail (11), and the X-ray detector (6) can move along the detector guide rail (11); The upper turntable (8), the third slit adjuster (4), the fourth slit adjuster (5), and the detector guide rail (11) are fixed on an extension table (15), and the extension table (15) is fixed on a lower turntable (7). Both the lower turntable (7) and the upper turntable (8) are electric turntables. The center line of the rotation axis of the lower turntable (7) coincides with the center line of the rotation axis of the upper turntable (8), and the lower turntable (7) is mounted on an optical platform (12).

2. The single-energy X-ray radiation device according to claim 1, characterized in that: The slit width of the horizontal slit and the slit width of the vertical slit are both 0.05 mm to 5 mm, and the slit length of the horizontal slit and the slit length of the vertical slit are both 100 mm.

3. The mono-energy X-ray radiation device according to claim 1, characterized in that: The target material of the X-ray source (1) is one of a W target, a Mo target and a Cu target. The maximum tube voltage of the X-ray source (1) is 50 kV, the maximum tube current is 1 mA, and the focal spot size is 1 mm×1 mm.

4. The mono-energy X-ray radiation device according to claim 1, characterized in that: The target material of the X-ray source (1) is a W target, the tube voltage is set to 8 kV, the tube current is set to 0.8 mA, and the focal spot size is 1 mm×1 mm.

5. The mono-energy X-ray radiation device according to claim 1, characterized in that: The Si single crystal (13) is one of Si (220), Si (311), Si (400), Si (331), and Si (224).

6. The mono-energy X-ray radiation device according to claim 1, characterized in that: The rotation accuracy of the lower turntable (7) and the upper turntable (8) is 0.01°.

7. The mono-energy X-ray radiation device according to claim 1, characterized in that: The X-ray detector (6) is one of a silicon drift detector, a CdZnTe detector and a high-purity germanium detector, with a response energy range of 1 keV to 100 keV, an energy resolution of less than 5%, and a detection efficiency of more than 80%.

8. A method for generating monoenergetic X-rays based on Si single crystal diffraction, using any monoenergetic X-ray radiation device according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1, install Si single crystal: Setting an X-ray detector (6) and a Si single crystal (13); Installing a set X-ray detector (6) on a detector guide rail (11), and installing a set Si single crystal (13) on a sample placement table (9); Step 2, set the angle range and rotation step of the lower turntable (7) and the upper turntable (8): Setting the rotation angle range and rotation step length of the lower turntable (7), and the rotation angle range and rotation step length of the upper turntable (8); The relationship between the rotation angle α1 of the lower turntable (7) and the rotation angle α2 of the upper turntable (8) is: α1＝-2α2 The rotation angle α1 of the lower turntable (7) or the rotation angle α2 of the upper turntable (8) is positive, indicating a clockwise direction; the rotation angle α1 of the lower turntable (7) or the rotation angle α2 of the upper turntable (8) is negative, indicating a counterclockwise direction; Step 3, test the X-ray spectrum: Starting the X-ray source (1), the X-ray detector (6), the lower turntable (7) and the upper turntable (8); The lower turntable (7) and the upper turntable (8) are rotated according to the set rotation angle range and rotation step length, and the X-ray energy spectrum is tested once by the X-ray detector (6) every time the lower turntable (7) and the upper turntable (8) rotate one step length.

9. The method for generating monoenergetic X-rays according to claim 8, characterized in that: The Si single crystal (13) is set to be Si (400), and the X-ray detector (6) is set to be a silicon drift detector; The lower turntable (7) rotates at an angle of 84° to 98°, with a step length of 0.2° and a clockwise direction; the upper turntable (8) rotates at an angle of -42° to -49°, with a step length of -0.1° and a counterclockwise direction; each time the lower turntable (7) and the upper turntable (8) rotate by one step, the X-ray energy spectrum is tested once using a silicon drift detector, and the integration time is 60 seconds.

10. The method for generating monoenergetic X-rays according to claim 8, characterized in that: The Si single crystal (13) is set to be Si (311), and the X-ray detector (6) is set to be a silicon drift detector; The lower turntable (7) rotates at an angle of 84° to 92°, with a step length of 1° and a clockwise direction; the upper turntable (8) rotates at an angle of -42° to -46°, with a step length of -0.5° and a counterclockwise direction; each time the lower turntable (7) and the upper turntable (8) rotate by one step, the X-ray energy spectrum is tested once using a silicon drift detector, and the integration time is 60 seconds.

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