A study of the long-term behavior of galactic X-ray sources with RXTE

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2001.

Bibliographic Details
Main Author: Wen, Linqing, 1969-
Other Authors: Hale V.D. Bradt.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2005
Subjects:
Online Access:http://hdl.handle.net/1721.1/8278
_version_ 1811088432116531200
author Wen, Linqing, 1969-
author2 Hale V.D. Bradt.
author_facet Hale V.D. Bradt.
Wen, Linqing, 1969-
author_sort Wen, Linqing, 1969-
collection MIT
description Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2001.
first_indexed 2024-09-23T14:02:06Z
format Thesis
id mit-1721.1/8278
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T14:02:06Z
publishDate 2005
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/82782019-04-12T20:33:50Z A study of the long-term behavior of galactic X-ray sources with RXTE Wen, Linqing, 1969- Hale V.D. Bradt. Massachusetts Institute of Technology. Dept. of Physics. Massachusetts Institute of Technology. Dept. of Physics. Physics. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2001. Includes bibliographical references (p. 145-157). I have carried out several investigations of the long-term behavior of galactic X-ray sources using the 4.5-year database of the All Sky Monitor (ASM), and pointed observations made with the Proportional Counter Array (PCA) on board the Rossi X-ray Timing Explorer (RXTE). I have conducted a systematic search through the ASM data of all the 300 X-ray sources monitored for evidence of periodic behavior. Follow-up investigations are pursued on the discoveries I made in (1) the state transition and orbital modulation of the black hole candidate Cyg X-1; (2) a 4.4-d period in a previously poorly-known X-ray source X 1908+075; and (3) a 98-d period in another previously poorly known X-ray source XTE J1716-389. In Cyg X-1, I have detected its orbital period in the low-hard state but not in the high-soft state. I show that absorption of X-rays by a stellar wind from the companion star can reproduce the observed modulations in the hard state. To explain the low orbital modulation in the soft-state data, a reduction of the wind density during the soft state would be required. In addition, I have discovered an evolution of the correlation between the 1.5-12 keV X-ray count rate of Cyg X-1 and its spectral hardness during the 1996 spectral state transition. I present a quantitative study of this evolution using both the ASM and the PCA data. Implications of our findings are discussed. I have discovered a 4.4-d period in the ASM light curves of the X-ray source XTE J1716-389. I present the results of the investigations on this 98-d periodic modulation using both the ASM and the PCA data. The possible cause of this period and the nature of this system are discussed. by Linqing Wen. Ph.D. 2005-08-23T18:50:16Z 2005-08-23T18:50:16Z 2001 2001 Thesis http://hdl.handle.net/1721.1/8278 50419445 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 157 p. 11021930 bytes 11021685 bytes application/pdf application/pdf application/pdf Massachusetts Institute of Technology
spellingShingle Physics.
Wen, Linqing, 1969-
A study of the long-term behavior of galactic X-ray sources with RXTE
title A study of the long-term behavior of galactic X-ray sources with RXTE
title_full A study of the long-term behavior of galactic X-ray sources with RXTE
title_fullStr A study of the long-term behavior of galactic X-ray sources with RXTE
title_full_unstemmed A study of the long-term behavior of galactic X-ray sources with RXTE
title_short A study of the long-term behavior of galactic X-ray sources with RXTE
title_sort study of the long term behavior of galactic x ray sources with rxte
topic Physics.
url http://hdl.handle.net/1721.1/8278
work_keys_str_mv AT wenlinqing1969 astudyofthelongtermbehaviorofgalacticxraysourceswithrxte
AT wenlinqing1969 studyofthelongtermbehaviorofgalacticxraysourceswithrxte