首页 | 本学科首页   官方微博 | 高级检索  
     检索      


The RHESSI Imaging Concept
Authors:Hurford  GJ  Schmahl  EJ  Schwartz  RA  Conway  AJ  Aschwanden  MJ  Csillaghy  A  Dennis  BR  Johns-Krull  C  Krucker  S  Lin  RP  McTiernan  J  Metcalf  TR  Sato  J  Smith  DM
Institution:(1) Space Sciences Laboratory, University of California, Berkeley, CA, 94720, U.S.A;(2) Astronomy Department, University of Maryland, College Park, MD, 20742, U.S.A;(3) Lab for Astronomy and Solar Physics, NASA Goddard Space Flight Center, USA;(4) Department of Physics and Astronomy, The Open University, Milton Keynes, MK7 6AA, U.K;(5) Solar & Astrophysics Laboratory, Dept. L9-41, Lockheed Martin Advanced Technology Center, Palo Alto, CA, 94304, U.S.A;(6) University of Applied Sciences, CH-5210 Windisch, Switzerland;(7) Department of Physics and Astronomy, Rice University, Houston, TX, 77005, U.S.A;(8) Department of Physics, University of California, Berkeley, CA, 94720, U.S.A;(9) Department of Physics, Montana State University, Bozeman, MT, 59717, U.S.A
Abstract:The Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) observes solar hard X-rays and gamma-rays from 3 keV to 17 MeV with spatial resolution as high as 2.3 arc sec. Instead of focusing optics, imaging is based on nine rotating modulation collimators that time-modulate the incident flux as the spacecraft rotates. Starting from the arrival time of individual photons, ground-based software then uses the modulated signals to reconstruct images of the source. The purpose of this paper is to convey both an intuitive feel and the mathematical basis for this imaging process. Following a review of the relevant hardware, the imaging principles and the basic back-projection method are described, along with their relation to Fourier transforms. Several specific algorithms (Clean, MEM, Pixons and Forward-Fitting) applicable to RHESSI imaging are briefly described. The characteristic strengths and weaknesses of this type of imaging are summarized.
Keywords:
本文献已被 SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号