A new method is proposed here aiming at designing a shielding wall with the efficiency significantly higher than that of traditional designs. This new design arises from the idea of using channeling in multilayered sh...A new method is proposed here aiming at designing a shielding wall with the efficiency significantly higher than that of traditional designs. This new design arises from the idea of using channeling in multilayered shielding wall structure, each layer composed of bent crystallites distributed in a way that each layer covers a small section of 2π angular range of which wall is exposed. Part of the incident charged particles will get channeled in bent crystallites in each layer. Bending of channeled particles in bent crystallites will change their directions in the wall increasing their path lengths in the wall which would enhance its shielding efficiency for charged particle radiations. Proposed design is useful for radiation shielding in fission power plants, future fusion reactors and air travel.展开更多
In spectral diagnostic physics experiments of inertial confinement fusion, the spectral signal is weak due to the low diffraction efficiency when using bent crystals. A spectral diagnostic instrument with high efficie...In spectral diagnostic physics experiments of inertial confinement fusion, the spectral signal is weak due to the low diffraction efficiency when using bent crystals. A spectral diagnostic instrument with high efficiency and wide spectral range is urgently needed. A multi-curvature bent crystal with multi-energy focusing ability is proposed based on the traditional conical crystal geometry. It has advantages of wide spectral range, strong focusing ability, and high spectral resolution. It also can eliminate the imaging aberration in principle due to rotational symmetry for the incoming X rays. A spectral diagnostic experiment based on a fabricated multi-curvatureα-quartz crystal was accomplished using a titanium X-ray tube of the bent crystal, and the corresponding experimental data using a plane α-quartz crystal was also acquired to demonstrate the strong focusing ability.The result shows that the Kα intensity of the multi-curvature α-quartz crystal is 157 times greater than that of the plane crystal, and the corresponding energy range is about 4.51–5.14 keV. This diagnostic instrument could be combined with a streak camera at a vertical direction so as to intensify the diffracted X-ray signal with a wide spectral range.展开更多
An aberration-free imaging technique was used to design a double-spherically bent crystal spectrometer with high energy and spatial resolutions to ensure that the individual spectral lines are represented as perfectly...An aberration-free imaging technique was used to design a double-spherically bent crystal spectrometer with high energy and spatial resolutions to ensure that the individual spectral lines are represented as perfectly straight lines on the detector.After obtaining the matched parameters of the two crystals via geometry-based optimization,an alignment method was employed to allow the spacing between the crystals and the detector to be coupled with the source.The working principle of this spectrum-measuring scheme was evaluated using a Cu X-ray tube.High-quality spectra with energy resolutions(E/ΔE)of approximately 3577 were obtained for a relatively large source size.展开更多
文摘A new method is proposed here aiming at designing a shielding wall with the efficiency significantly higher than that of traditional designs. This new design arises from the idea of using channeling in multilayered shielding wall structure, each layer composed of bent crystallites distributed in a way that each layer covers a small section of 2π angular range of which wall is exposed. Part of the incident charged particles will get channeled in bent crystallites in each layer. Bending of channeled particles in bent crystallites will change their directions in the wall increasing their path lengths in the wall which would enhance its shielding efficiency for charged particle radiations. Proposed design is useful for radiation shielding in fission power plants, future fusion reactors and air travel.
基金supported in part by the National Natural Science Foundation of China (Nos. 61604028 and61804019)the Venture&Innovation Support Program for Chongqing Overseas Returnees (No. cx2018023)the Science and Technology on Plasmas Physics Laboratory (No. 6142A04180207)。
文摘In spectral diagnostic physics experiments of inertial confinement fusion, the spectral signal is weak due to the low diffraction efficiency when using bent crystals. A spectral diagnostic instrument with high efficiency and wide spectral range is urgently needed. A multi-curvature bent crystal with multi-energy focusing ability is proposed based on the traditional conical crystal geometry. It has advantages of wide spectral range, strong focusing ability, and high spectral resolution. It also can eliminate the imaging aberration in principle due to rotational symmetry for the incoming X rays. A spectral diagnostic experiment based on a fabricated multi-curvatureα-quartz crystal was accomplished using a titanium X-ray tube of the bent crystal, and the corresponding experimental data using a plane α-quartz crystal was also acquired to demonstrate the strong focusing ability.The result shows that the Kα intensity of the multi-curvature α-quartz crystal is 157 times greater than that of the plane crystal, and the corresponding energy range is about 4.51–5.14 keV. This diagnostic instrument could be combined with a streak camera at a vertical direction so as to intensify the diffracted X-ray signal with a wide spectral range.
基金This work was supported by the National Natural Science Foundation of China(No.11575168).
文摘An aberration-free imaging technique was used to design a double-spherically bent crystal spectrometer with high energy and spatial resolutions to ensure that the individual spectral lines are represented as perfectly straight lines on the detector.After obtaining the matched parameters of the two crystals via geometry-based optimization,an alignment method was employed to allow the spacing between the crystals and the detector to be coupled with the source.The working principle of this spectrum-measuring scheme was evaluated using a Cu X-ray tube.High-quality spectra with energy resolutions(E/ΔE)of approximately 3577 were obtained for a relatively large source size.
