TY - JOUR
T1 - Development of a single-shot CCD-based data acquisition system for time-resolved X-ray photoelectron spectroscopy at an X-ray free-electron laser facility
AU - Oura, Masaki
AU - Wagai, Tatsuya
AU - Chainani, Ashish
AU - Miyawaki, Jun
AU - Sato, Hiromi
AU - Matsunami, Masaharu
AU - Eguchi, Ritsuko
AU - Kiss, Takayuki
AU - Yamaguchi, Takashi
AU - Nakatani, Yasuhiro
AU - Togashi, Tadashi
AU - Katayama, Tetsuo
AU - Ogawa, Kanade
AU - Yabashi, Makina
AU - Tanaka, Yoshihito
AU - Kohmura, Yoshiki
AU - Tamasaku, Kenji
AU - Shin, Shik
AU - Ishikawa, Tetsuya
PY - 2014/1
Y1 - 2014/1
N2 - In order to utilize high-brilliance photon sources, such as X-ray free-electron lasers (XFELs), for advanced time-resolved photoelectron spectroscopy (TR-PES), a single-shot CCD-based data acquisition system combined with a high-resolution hemispherical electron energy analyzer has been developed. The system's design enables it to be controlled by an external trigger signal for single-shot pump-probe-type TR-PES. The basic performance of the system is demonstrated with an offline test, followed by online core-level photoelectron and Auger electron spectroscopy in 'single-shot image', 'shot-to-shot image (image-to-image storage or block storage)' and 'shot-to-shot sweep' modes at soft X-ray undulator beamline BL17SU of SPring-8. In the offline test the typical repetition rate for image-to-image storage mode has been confirmed to be about 15 Hz using a conventional pulse-generator. The function for correcting the shot-to-shot intensity fluctuations of the exciting photon beam, an important requirement for the TR-PES experiments at FEL sources, has been successfully tested at BL17SU by measuring Au 4f photoelectrons with intentionally controlled photon flux. The system has also been applied to hard X-ray PES (HAXPES) in 'ordinary sweep' mode as well as shot-to-shot image mode at the 27 m-long undulator beamline BL19LXU of SPring-8 and also at the SACLA XFEL facility. The XFEL-induced Ti 1s core-level spectrum of La-doped SrTiO3 is reported as a function of incident power density. The Ti 1s core-level spectrum obtained at low power density is consistent with the spectrum obtained using the synchrotron source. At high power densities the Ti 1s core-level spectra show space-charge effects which are analysed using a known mean-field model for ultrafast electron packet propagation. The results successfully confirm the capability of the present data acquisition system for carrying out the core-level HAXPES studies of condensed matter induced by the XFEL.
AB - In order to utilize high-brilliance photon sources, such as X-ray free-electron lasers (XFELs), for advanced time-resolved photoelectron spectroscopy (TR-PES), a single-shot CCD-based data acquisition system combined with a high-resolution hemispherical electron energy analyzer has been developed. The system's design enables it to be controlled by an external trigger signal for single-shot pump-probe-type TR-PES. The basic performance of the system is demonstrated with an offline test, followed by online core-level photoelectron and Auger electron spectroscopy in 'single-shot image', 'shot-to-shot image (image-to-image storage or block storage)' and 'shot-to-shot sweep' modes at soft X-ray undulator beamline BL17SU of SPring-8. In the offline test the typical repetition rate for image-to-image storage mode has been confirmed to be about 15 Hz using a conventional pulse-generator. The function for correcting the shot-to-shot intensity fluctuations of the exciting photon beam, an important requirement for the TR-PES experiments at FEL sources, has been successfully tested at BL17SU by measuring Au 4f photoelectrons with intentionally controlled photon flux. The system has also been applied to hard X-ray PES (HAXPES) in 'ordinary sweep' mode as well as shot-to-shot image mode at the 27 m-long undulator beamline BL19LXU of SPring-8 and also at the SACLA XFEL facility. The XFEL-induced Ti 1s core-level spectrum of La-doped SrTiO3 is reported as a function of incident power density. The Ti 1s core-level spectrum obtained at low power density is consistent with the spectrum obtained using the synchrotron source. At high power densities the Ti 1s core-level spectra show space-charge effects which are analysed using a known mean-field model for ultrafast electron packet propagation. The results successfully confirm the capability of the present data acquisition system for carrying out the core-level HAXPES studies of condensed matter induced by the XFEL.
KW - X-ray free-electron laser
KW - data acquisition system
KW - hard X-ray photoelectron spectroscopy
KW - shot-to-shot measurement
KW - soft X-ray photoelectron spectroscopy
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U2 - 10.1107/S1600577513028233
DO - 10.1107/S1600577513028233
M3 - Article
AN - SCOPUS:84891587961
VL - 21
SP - 183
EP - 192
JO - Journal of Synchrotron Radiation
JF - Journal of Synchrotron Radiation
SN - 0909-0495
IS - 1
ER -