On-line high-temperature X-ray radiation source with uniformly distributed space

Abstract

The invention discloses a spatially uniformly-distributed online high-temperature X-ray radiation source, and relates to the technical field of X-ray radiation sources, the spatially uniformly-distributed online high-temperature X-ray radiation source comprises a laser beam and a black cavity, the black cavity is of a columnar structure with upper and lower openings and a hollowed middle, a partition plate is added to the waist to uniformly divide the black cavity into two sections, and shielding sheets are arranged at the two ends of the black cavity respectively; laser beams enter the black cavity from the holes in the upper end and the lower end, the laser and the wall of the black cavity act and are converted into X-rays, and therefore a high-temperature X-ray radiation source is formed in the black cavity. The on-line high-temperature X-ray radiation source provided by the invention is simple in structure, easy to implement, stable in light source intensity and uniform in black cavity radiation temperature space distribution, and can provide a good on-line calibration light source for FXRD and other radiation temperature measuring devices.

Description

Technical Field

[0001] The invention relates to the technical field of X-ray radiation sources, and in particular to an online high-temperature X-ray radiation source with uniform spatial distribution. Background Art

[0002] The high-temperature X-ray radiation source generated by laser-driven high-Z black cavity is an important means for conducting high-energy density physical experimental research such as indirect-driven inertial confinement fusion, laboratory astrophysics and high-pressure state equation. Precise measurement of black cavity radiation temperature is the basis for accurately evaluating processes such as fluid movement and material compression during radiation loading. Flat response radiation flow detector (FXRD) is usually used to measure black cavity radiation temperature. FXRD consists of a combined filter and Au cathode. In order to ensure the measurement accuracy of FXRD, it is necessary to calibrate the filter transmittance and cathode response respectively using the standard X-ray radiation source provided by the synchrotron radiation device before the formal experiment. However, in the actual physical experiment process, the filter transmittance and cathode response will gradually change over time. For example, the filter "sand eyes" formed by target fragments cause the filter transmittance to gradually increase, and the oxidation of the cathode causes the cathode response to gradually decrease. For this reason, it is necessary to establish a simple and stable online high-temperature X-ray radiation source to facilitate real-time assessment of the measurement accuracy of FXRD.

[0003] Laser injection into a vacuum column cavity can obtain a relatively stable and robust high-temperature X-ray radiation source. The physical process is as follows: the laser deposits energy at the spot on the cavity wall through the reverse bremsstrahlung absorption process, and the high-temperature plasma at the spot emits X-rays. These X-rays are then continuously absorbed and reflected on the cavity wall, and finally form a quasi-blackbody radiation field in the black cavity. The radiation temperature of the black cavity is directly measured using FXRD, and the black cavity radiation temperature is normalized according to the laser energy. By comparing it with the historical standard data of the black cavity radiation temperature, the measurement state of FXRD can be judged. However, the radiation field in the black cavity is not an ideal blackbody radiation. In fact, the number of spots on the cavity wall is limited. At the same time, due to the influence of two pairs of perforations on the black cavity, the radiation temperature of the black cavity at different angles will significantly deviate from the spatial uniform distribution, which is not conducive to cross-checking FXRD at different angles; in addition, due to the limited spot area in the field of view, the spot position deviation of the laser beam and the energy balance between the laser beams will lead to statistical fluctuations in the radiation temperature of the black cavity, which is also not conducive to the assessment of FXRD. Therefore, a spatially uniformly distributed and stable X-ray radiation source has become an urgent problem to be solved. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an online X-ray radiation source with uniform spatial distribution and stable intensity. The influence of the black cavity on perforation is avoided by adding a partition plate at the waist of the black cavity. The situation of limited spot area in the field of view is improved by increasing the number of spots on the cavity wall. The radiation field in the black cavity is closer to the ideal blackbody radiation, and the spatial distribution of the black cavity radiation temperature is more uniform.

[0005] In order to solve the above technical problems, the technical solution provided by the present invention is: an online high-temperature X-ray radiation source with uniform spatial distribution, including a laser beam and a black cavity, the black cavity is a columnar structure with upper and lower openings and a hollow middle, a partition is provided in the middle of the black cavity to evenly divide the black cavity into upper and lower parts, and shielding plates are provided on the outer sides of the upper and lower ends of the black cavity, the laser beam is emitted into the interior of the black cavity from the openings at the upper and lower ends of the black cavity, and the laser beam reacts with the black cavity wall to be converted into X-rays, thereby forming a high-temperature X-ray radiation source in the black cavity.

[0006] Furthermore, the height of the black cavity is 1800 μm, the diameter of the black cavity is 1600 μm, the diameters of the openings at the upper and lower ends of the black cavity are both 1400 μm, and the center of the opening coincides with the center of the end faces on both sides.

[0007] Furthermore, the black cavity is made of Au, and the thickness of the cavity wall of the black cavity is 25-50 μm.

[0008] Furthermore, the partition is in a disc shape, is made of Au, has a thickness of 25 to 50 μm, and is located in the middle plane of the black cavity.

[0009] Furthermore, the shielding piece is in the shape of a hollow ring, and is made of Cu and has CH (carbon hydrogen plastic) plated on the surface.

[0010] Furthermore, the wavelength of the laser beam is 351 nm, the energy of a single laser beam is 700-900 J, and the laser pulse is a 1 ns square wave; the number of incident laser beams is 48 beams, which are incident from both ends of the black cavity in groups of 24 beams.

[0011] The advantages of the present invention over the prior art are as follows: the online high-temperature X-ray radiation source provided by the present invention has a simple structure and is easy to implement. By increasing the number of light spots on the waist baffle and the cavity wall of the black cavity, the radiation field in the black cavity is closer to the ideal blackbody radiation. The light source intensity is stable, and the spatial distribution of the black cavity radiation temperature is uniform, which can provide a good online calibration light source for radiation temperature measurement devices such as FXRD. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of a spatially uniformly distributed online high-temperature X-ray radiation source of the present invention.

[0013] Figure 2 It is a working schematic diagram of a spatially uniformly distributed online high-temperature X-ray radiation source of the present invention.

[0014] Figure 3 It is a black cavity radiation temperature curve obtained by measuring at different angles a spatially uniformly distributed online high-temperature X-ray radiation source of the present invention.

[0015] As shown in the figure: 1. Laser beam, 2. Black cavity, 3. Partition, 4. Shielding sheet, 5. FXRD. DETAILED DESCRIPTION

[0016] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “inside”, “outside”, “vertical” and “circumferential” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0017] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] The following is a further detailed description of a spatially uniformly distributed online high-temperature X-ray radiation source of the present invention in conjunction with the accompanying drawings.

[0019] Combined with Figure 1-3 , the present invention is introduced in detail.

[0020] Combined with Figure 1 A spatially uniformly distributed online high-temperature X-ray radiation source comprises a laser beam 1 and a black cavity 2. The black cavity 2 is a columnar structure with upper and lower openings and a hollow middle. A partition plate 3 is added at the waist to evenly divide the black cavity 2 into two sections. Shielding plates 4 are respectively provided at both ends of the black cavity 2. The laser beam 1 enters the black cavity 2 from the openings at the upper and lower ends. The laser reacts with the wall of the black cavity 2 to convert into X-rays, thereby forming a high-temperature X-ray radiation source in the black cavity 2.

[0021] During implementation, the height of the black cavity 2 is 1800 μm, the diameter of the black cavity 2 is 1600 μm, the diameter of the openings at both ends is 1400 μm, and the center of the opening coincides with the center of the end faces on both sides.

[0022] During implementation, the black cavity 2 is made of Au, and the cavity wall thickness is 25-50 μm.

[0023] During implementation, the partition 3 is in the shape of a disk, is made of Au, has a thickness of 25 to 50 μm, and is located in the middle plane of the black cavity 2 .

[0024] During implementation, the shielding piece 4 is in a hollow ring shape, and is made of Cu with CH (carbon hydrogen plastic) plated on the surface.

[0025] During implementation, the wavelength of the laser beam 1 is 351 nm, the energy of a single laser beam is 700-900 J, and the laser pulse is a 1 ns square wave; the incident laser beam 1 is 48 beams, which are incident from both ends of the black cavity 2 in groups of 24 beams.

[0026] The specific implementation process of the spatially uniformly distributed online high-temperature X-ray radiation source of the present invention is as follows:

[0027] In actual measurement, it is also necessary to introduce a black cavity 2 radiation temperature measurement instrument to measure the black cavity 2 radiation temperature at different angles. Figure 2 The black cavity 2 radiation temperature measuring instrument is preferably FXRD5, which is composed of a combined filter and an Au cathode. The laser beam 1 is incident from both ends of the black cavity 2, and the laser interacts with the wall of the black cavity 2 to generate a high-temperature X-ray radiation source. FXRD5 is placed at different angles of the black cavity 2 to measure the X-ray radiation flow leaked from the opening of the black cavity 2, so that the radiation temperature of the black cavity 2 at different angles can be obtained. Figure 3 The radiation temperature curve of the black cavity 2 is given, where Tr is the radiation temperature of the black cavity 2, and A, B, C, and D are the radiation temperature curves of the black cavity 2 measured at different angles.

[0028] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A spatially uniformly distributed online high-temperature X-ray radiation source, characterized in that: The invention comprises a laser beam (1) and a black cavity (2). The black cavity (2) is a columnar structure with upper and lower openings and a hollow middle portion. A partition (3) is provided in the middle of the black cavity (2) to evenly divide the black cavity (2) into upper and lower parts. Shielding plates (4) are provided on the outer sides of the upper and lower ends of the black cavity (2). The laser beam (1) is emitted into the interior of the black cavity (2) from the openings at the upper and lower ends of the black cavity (2). The laser beam (1) reacts with the wall of the black cavity (2) to convert into X-rays, thereby forming a high-temperature X-ray radiation source in the black cavity (2).

2. The spatially uniformly distributed online high-temperature X-ray radiation source according to claim 1, characterized in that: The height of the black cavity (2) is 1800 μm, the diameter of the black cavity (2) is 1600 μm, the diameters of the openings at the upper and lower ends of the black cavity (2) are both 1400 μm, and the center of the opening coincides with the center of the end faces on both sides.

3. The spatially uniformly distributed online high-temperature X-ray radiation source according to claim 2, characterized in that: The black cavity (2) is made of Au, and the wall thickness of the black cavity (2) is 25-50 μm.

4. The spatially uniformly distributed online high-temperature X-ray radiation source according to claim 3, characterized in that: The partition (3) is in the shape of a disk, is made of Au, has a thickness of 25 to 50 μm, and is located in the middle plane of the black cavity (2).

5. The spatially uniformly distributed online high-temperature X-ray radiation source according to claim 4, characterized in that: The shielding piece (4) is in the shape of a hollow ring, and is made of Cu and has a surface plated with CH.

6. The spatially uniformly distributed online high-temperature X-ray radiation source according to claim 5, characterized in that: The wavelength of the laser beam (1) is 351 nm, the energy of a single laser beam is 700-900 J, and the laser pulse is a 1 ns square wave; the incident laser beams (1) are 48 beams, which are incident from both ends of the black cavity (2) in groups of 24 beams.

Images