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Coherence, as a core element of cutting-edge X-ray research technology, has driven the vigorous development of many experiments such as coherent X-ray diffraction imaging and X-ray holography in the past two decades, and has also promoted the construction of fourth generation synchrotron radiation sources and hard X-ray free electron lasers. To measure the size of synchrotron radiation light source and coherence of beamline, an X-ray measurement system based on 2D single grating interferometry was established. Conduct research on the measurement principles and propagation models used in the system. Firstly, based on the VanCittert-Zernike theorem, the relationship between the visibility of the interference lattice and the spatial coherence of X-rays is given. Secondly, combined with the Talbot self imaging effect of a single grating, the X-ray spatial coherence length of the plane where the grating is located is measured, and the spatial distribution of the corresponding light source is obtained through further calculation. The relevant measurement experiments of this study were conducted at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility (SSRF). A 2D checkerboard π phase-shift grating was used as the core device in the experiment. This setup not only enabled the acquisition of transverse coherence lengths in the vertical and horizontal directions but also further measured the transverse coherence lengths in the directions forming 45° and 135° angles with the horizontal direction. The experimental process strictly followed the technical specifications outlined in this paper: along the beam propagation direction, interferograms were measured at different positions downstream of the phase grating. For each interferogram, the corresponding visibility values were extracted by analyzing the harmonic peaks in its Fourier-transformed image. Ultimately, the transverse coherence length in each direction could be derived based on the evolution law of visibility as a function of the grating-to-detector distance. The experimental results show that the coherence length of the emitted X-rays on SSRF testline is 4.2 μm (H)x13.8 μm (V) @ 15 keV, and the size of the bending magnet source is 124 μm (H)x38 μm (V). The results obtained by this method can provide important references for measuring the electron source size and the development of experimental methods with high requirements for uniform illumination.
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Keywords:
- Synchrotron radiation /
- X-ray single-grating interferometry /
- Coherence /
- Source size
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[1] Zhou G Z, Tong Y J, Chen C, Ren Y Y, Wang Y D, Xiao T Q 2011 Acta Phys. Sin. 60 028701 (in Chinese) [周光照, 佟亚军, 陈灿, 任玉琦, 王玉丹, 肖体乔. 2011物理学报 60 28701]
[2] Mcnulty I, Kirz J, Jacobsen C, Anderson E H, Howells M R, Kern D P 1992 Science 256 1009
[3] Grubel G, Zontone F 2004 Alloys. Compd. 362 3
[4] Wilkins S W, Nesterets Y I, Gureyev T E 2014 Phil. Trans. R. Soc. A 372 0021
[5] Yoshio S 2004 Rev. Sci. Instrum. 75 1026
[6] Guigay JP, Zabler S, Cloetens P, David C, Mokso R, Schlenker M 2004 J. Synchrotron Rad. 11 476
[7] Rutishauser S, Samoylova L, Krzywinski J, Bunk O, Grünert J, Sinn H, Cammarata M, Fritz D M, David C 2012 Nature Communications 3 947
[8] Wang H, Sawhney K, Berujon S 2014 Opt. Lett. 39 2518
[9] Qi J C, Ye L L, Chen R C, Xie H L, Ren Y Q, Du G H, Deng B, Xiao T Q 2014 Acta Phys. Sin. 63 104202 (in Chinese) [戚俊成, 叶琳琳, 陈荣昌, 谢红兰,任玉琦,杜国浩,邓彪,肖体乔 2014 物理学报 63 104202]
[10] Matsuyama S, Yokoyama H, Fukui R, Kohmura Y, Tamasaku K, Yabashi M, Yashiro W, Momose A, Ishikawa T, Yamauchi K 2012 Opt. Express 20 24977
[11] Liu Y, Seaberg M, Zhu D, Krzywinski J, Seiboth F, Hardin C, Cocco D, Aquila A, Nagler B, Lee H J, Boutet S, Feng Y, Ding Y, Marcus G, Sakdinawat A 2018 Optica 5 967
[12] Inoue T, Matsuyama S, Kawai S, Yumoto H, Inubushi Y, Osaka T, Inoue I, Koyama T, Tono K, Ohashi H, Yabashi M, Ishikawa T, Yamauchi K 2018 Rev. Sci. Instrum. 89 043106
[13] Born M, Wolf, E 1999 Principles of Optics 7th ed.(Cambridgeshire: Cambridge University Press) pp 554-632
[14] Li Z, Fan Y, Xue L, Zhang Z, Wang J 2019 Proceedings Of The 13th International Conference On Synchrotron Radiation Instrumentation-Sri2018 Taipei, Taiwan June 11–15, 2018 060040
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