MEDSI2018 - List of Authors (Tang, S.)

Paper	Title	Page
WEOAMA03	High-Accuracy Small Roll Angle Measurement Method Based on Dual-Grating Diffraction Heterodyne Interferometer	163
	S. Tang, M. Li, H. Liang, W.F. Sheng, J. Yang IHEP, Beijing, People's Republic of China
	Funding: The work is supported by National Natural Science Foundation of China, NSFC (Grant No. 61505213). Small roll angle (ROLL) is an crucial parameter for the motion performances of ultra-precision guide way often applied in fine mechanics and instruments of synchrotron radiation, such as long trace profiler (LTP). However, it is difficult to be measured by conventional methods including interferometer and autocollimator owing to their low sensitivities in axial direction. There is an orthogonal dilemma between measured direction and angular displacement plane for ROLL measurement. Therefore, a novel method based on dual-grating diffraction heterodyne interferometer is presented, which uses the combining scheme of diffraction grating and heterodyne interferometer to overcome the orthogonal problem. Moreover, the design of differential structure with dual-grating and grating interferometer instead of pure interferometer, is adopted to improve the practicability against the environment, e. g. air fluctuation, inconstant rotation center. It has inherited advantages of high-resolution up to 2nrad, high sampling rate up to 50kHz, and contactless by mathematical modeling and analysis. So, theoretcial and experimental verifications are both implemented to its validation.
	Slides WEOAMA03 [2.304 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-WEOAMA03
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FROAMA02	A High Heat Load Double Crystal Monochromator and Its Cryo Cooling System for Heps	430
	H. Liang, L. Gao, Y.C. Jiang, W.F. Sheng, S. Tang, A.Y. Zhou IHEP, Beijing, People's Republic of China G. Cao University of Chinese Academy of Sciences, Beijing, People's Republic of China
	A high heat load double crystal monochromator and its cryo cooling system were designed and their prototypes were fabricated for the future HEPS. The mechanical and cooling structure of the DCM are introduced. The FEA results show the DCM is capable of cooling 870 watts of heat load. The cryo cooling system is also introduced. Test results show the pressure stability of the cryo cooling system is less than 2 mbar RMS. Offline heat load test of the DCM were carried out by a ceramic heater attached to the center of the incident surface of the first crystal, and 834 watts heat load were applied by the heater without boiling the liquid nitrogen. Offline absolute vibration measurement of the second crystal assembly was carried out by a laser interferometer under different cryo pump speed, pressure and heat load conditions, to find out the stability performance accordingly. An absolute vibration of 41 nrad RMS was measured, with the pump running at 45Hz, which has a cooling capability of 400 watts.
	Slides FROAMA02 [7.370 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-FROAMA02
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROAMA03	R&D of Mirror Bending Techniques in BSRF
	M. Li, L. Gao, H. Han, Q. Han, X. Liu, S. Tang IHEP, Beijing, People's Republic of China
	High precision bending technology is development at Beijing Synchrotron Radiation Facility. We adopted two independent bending moment and variable width mirror geometry design, and no gravity compensation system, and use four rollers structure in long mirror bender and a special flexible hinge structure in short mirror bender. We test the benders' performance by our Flag-type LTP and get sub-200nrad RMS elliptical bending surface shape accuracy in full range, with 72h stability: 66nrad RMS for long mirror and 6nrad RMS for short mirror.
	Slides FROAMA03 [13.722 MB]
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Paper

Title

Page

High-Accuracy Small Roll Angle Measurement Method Based on Dual-Grating Diffraction Heterodyne Interferometer

163

S. Tang, M. Li, H. Liang, W.F. Sheng, J. Yang
IHEP, Beijing, People's Republic of China

Funding: The work is supported by National Natural Science Foundation of China, NSFC (Grant No. 61505213).
Small roll angle (ROLL) is an crucial parameter for the motion performances of ultra-precision guide way often applied in fine mechanics and instruments of synchrotron radiation, such as long trace profiler (LTP). However, it is difficult to be measured by conventional methods including interferometer and autocollimator owing to their low sensitivities in axial direction. There is an orthogonal dilemma between measured direction and angular displacement plane for ROLL measurement. Therefore, a novel method based on dual-grating diffraction heterodyne interferometer is presented, which uses the combining scheme of diffraction grating and heterodyne interferometer to overcome the orthogonal problem. Moreover, the design of differential structure with dual-grating and grating interferometer instead of pure interferometer, is adopted to improve the practicability against the environment, e. g. air fluctuation, inconstant rotation center. It has inherited advantages of high-resolution up to 2nrad, high sampling rate up to 50kHz, and contactless by mathematical modeling and analysis. So, theoretcial and experimental verifications are both implemented to its validation.

Slides WEOAMA03 [2.304 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-WEOAMA03

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROAMA02

A High Heat Load Double Crystal Monochromator and Its Cryo Cooling System for Heps

430

H. Liang, L. Gao, Y.C. Jiang, W.F. Sheng, S. Tang, A.Y. Zhou
IHEP, Beijing, People's Republic of China
G. Cao
University of Chinese Academy of Sciences, Beijing, People's Republic of China

A high heat load double crystal monochromator and its cryo cooling system were designed and their prototypes were fabricated for the future HEPS. The mechanical and cooling structure of the DCM are introduced. The FEA results show the DCM is capable of cooling 870 watts of heat load. The cryo cooling system is also introduced. Test results show the pressure stability of the cryo cooling system is less than 2 mbar RMS. Offline heat load test of the DCM were carried out by a ceramic heater attached to the center of the incident surface of the first crystal, and 834 watts heat load were applied by the heater without boiling the liquid nitrogen. Offline absolute vibration measurement of the second crystal assembly was carried out by a laser interferometer under different cryo pump speed, pressure and heat load conditions, to find out the stability performance accordingly. An absolute vibration of 41 nrad RMS was measured, with the pump running at 45Hz, which has a cooling capability of 400 watts.

Slides FROAMA02 [7.370 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2018-FROAMA02

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROAMA03

R&D of Mirror Bending Techniques in BSRF

M. Li, L. Gao, H. Han, Q. Han, X. Liu, S. Tang
IHEP, Beijing, People's Republic of China

High precision bending technology is development at Beijing Synchrotron Radiation Facility. We adopted two independent bending moment and variable width mirror geometry design, and no gravity compensation system, and use four rollers structure in long mirror bender and a special flexible hinge structure in short mirror bender. We test the benders' performance by our Flag-type LTP and get sub-200nrad RMS elliptical bending surface shape accuracy in full range, with 72h stability: 66nrad RMS for long mirror and 6nrad RMS for short mirror.

Slides FROAMA03 [13.722 MB]

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)