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Title: A Real-Time Imaging System for Stereo Atomic Microscopy at SPring-8's BL25SU

Abstract

We have developed a real-time photoelectron angular distribution (PEAD) and Auger-electron angular distribution (AEAD) imaging system at SPring-8 BL25SU, Japan. In addition, a real-time imaging system for circular dichroism (CD) studies of PEAD/AEAD has been newly developed. Two PEAD images recorded with left- and right-circularly polarized light can be regarded as a stereo image of the atomic arrangement. A two-dimensional display type mirror analyzer (DIANA) has been installed at the beamline, making it possible to record PEAD/AEAD patterns with an acceptance angle of {+-}60 deg. in real-time. The twin-helical undulators at BL25SU enable helicity switching of the circularly polarized light at 10Hz, 1Hz or 0.1Hz. In order to realize real-time measurements of the CD of the PEAD/AEAD, the CCD camera must be synchronized to the switching frequency. The VME computer that controls the ID is connected to the measurement computer with two BNC cables, and the helicity information is sent using TTL signals. For maximum flexibility, rather than using a hardware shutter synchronizing with the TTL signal we have developed software to synchronize the CCD shutter with the TTL signal. We have succeeded in synchronizing the CCD camera in both the 1Hz and 0.1Hz modes.

Authors:
; ;  [1]; ;  [2]
  1. JASRI/SPring-8, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo, 679-5198 (Japan)
  2. Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan)
Publication Date:
OSTI Identifier:
21049229
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436271; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ANGULAR DISTRIBUTION; CAMERAS; CHARGE-COUPLED DEVICES; COMPUTER CODES; CONTROL; DICHROISM; ELECTRONS; HELICITY; IMAGE PROCESSING; IMAGES; MIRRORS; PHOTOELECTRON COUNTING; REAL TIME SYSTEMS; SPRING-8 STORAGE RING; TIME MEASUREMENT; WIGGLER MAGNETS

Citation Formats

Matsushita, Tomohiro, Guo, Fang Zhun, Muro, Takayuki, Matsui, Fumihiko, and Daimon, Hiroshi. A Real-Time Imaging System for Stereo Atomic Microscopy at SPring-8's BL25SU. United States: N. p., 2007. Web. doi:10.1063/1.2436271.
Matsushita, Tomohiro, Guo, Fang Zhun, Muro, Takayuki, Matsui, Fumihiko, & Daimon, Hiroshi. A Real-Time Imaging System for Stereo Atomic Microscopy at SPring-8's BL25SU. United States. doi:10.1063/1.2436271.
Matsushita, Tomohiro, Guo, Fang Zhun, Muro, Takayuki, Matsui, Fumihiko, and Daimon, Hiroshi. Fri . "A Real-Time Imaging System for Stereo Atomic Microscopy at SPring-8's BL25SU". United States. doi:10.1063/1.2436271.
@article{osti_21049229,
title = {A Real-Time Imaging System for Stereo Atomic Microscopy at SPring-8's BL25SU},
author = {Matsushita, Tomohiro and Guo, Fang Zhun and Muro, Takayuki and Matsui, Fumihiko and Daimon, Hiroshi},
abstractNote = {We have developed a real-time photoelectron angular distribution (PEAD) and Auger-electron angular distribution (AEAD) imaging system at SPring-8 BL25SU, Japan. In addition, a real-time imaging system for circular dichroism (CD) studies of PEAD/AEAD has been newly developed. Two PEAD images recorded with left- and right-circularly polarized light can be regarded as a stereo image of the atomic arrangement. A two-dimensional display type mirror analyzer (DIANA) has been installed at the beamline, making it possible to record PEAD/AEAD patterns with an acceptance angle of {+-}60 deg. in real-time. The twin-helical undulators at BL25SU enable helicity switching of the circularly polarized light at 10Hz, 1Hz or 0.1Hz. In order to realize real-time measurements of the CD of the PEAD/AEAD, the CCD camera must be synchronized to the switching frequency. The VME computer that controls the ID is connected to the measurement computer with two BNC cables, and the helicity information is sent using TTL signals. For maximum flexibility, rather than using a hardware shutter synchronizing with the TTL signal we have developed software to synchronize the CCD shutter with the TTL signal. We have succeeded in synchronizing the CCD camera in both the 1Hz and 0.1Hz modes.},
doi = {10.1063/1.2436271},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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