Composition of the Chandra ACIS contaminant

被引:76
作者
Marshall, HL [1 ]
Tennant, A [1 ]
Grant, CE [1 ]
Hitchcock, AP [1 ]
O'Dell, S [1 ]
Plucinsky, PP [1 ]
机构
[1] MIT, Ctr Space Res, Cambridge, MA 02139 USA
来源
X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XIII | 2004年 / 5165卷
关键词
contamination; X-rays; telescopes; spectroscopy;
D O I
10.1117/12.508310
中图分类号
V [航空、航天];
学科分类号
08 ; 0825 ;
摘要
The Advanced CCD Imaging Spectrometer (ACIS) on the Chandra X-ray Observatory is suffering a gradual loss of low energy sensitivity due to a buildup of a contaminant. High resolution spectra of bright astrophysical sources using the Chandra Low Energy Transmission Grating Spectrometer (LETGS) have been analyzed in order to determine the nature of the contaminant by measuring the absorption edges. The dominant element in the contaminant is carbon. Edges due to oxygen and fluorine are also detectable. Excluding H, we find that C, O, and F comprise >80%, 7%, and 7% of the contaminant by number, respectively. Nitrogen is less than 3% of the contaminant. We will assess various candidates for the contaminating material and investigate the growth of the layer with time. For example, the detailed structure of the C-K absorption edge provides information about the bonding structure of the compound, eliminating aromatic hydrocarbons as the contaminating material.
引用
收藏
页码:497 / 508
页数:12
相关论文
共 6 条
[1]   ACIS UV/Optical blocking filter calibration at the National Synchrotron Light Source [J].
Chartas, G ;
Garmire, G ;
Nousek, J ;
Townsley, L ;
Powell, F ;
Blake, R ;
Graessle, D .
MULTILAYER AND GRAZING INCIDENCE X-RAY/EUV OPTICS III, 1996, 2805 :44-54
[2]   Advanced CCD imaging spectrometer (ACIS) instrument on the Chandra X-ray Observatory [J].
Garmire, GP ;
Bautz, MW ;
Ford, PG ;
Nousek, JA ;
Ricker, GR .
X-RAY AND GAMMA-RAY TELESCOPES AND INSTRUMENTS FOR ASTRONOMY, PTS 1 AND 2, 2003, 4851 :28-44
[3]   Interferometer-controlled scanning transmission X-ray microscopes at the Advanced Light Source [J].
Kilcoyne, ALD ;
Tyliszczak, T ;
Steele, WF ;
Fakra, S ;
Hitchcock, P ;
Franck, K ;
Anderson, E ;
Harteneck, B ;
Rightor, EG ;
Mitchell, GE ;
Hitchcock, AP ;
Yang, L ;
Warwick, T ;
Ade, H .
JOURNAL OF SYNCHROTRON RADIATION, 2003, 10 :125-136
[4]  
MARSHALL HL, 2003, P SPIE, V5165
[5]   The flight spectral response of the ACIS instrument [J].
Plucinsky, PP ;
Schulz, NS ;
Marshall, HL ;
Grant, CE ;
Chartas, G ;
Sanwal, D ;
Teter, MA ;
Vikhlinin, AA ;
Edgar, RJ ;
Wise, MW ;
Allen, GE ;
Virani, SN ;
DePasquale, JM ;
Raley, MT .
X-RAY AND GAMMA-RAY TELESCOPES AND INSTRUMENTS FOR ASTRONOMY, PTS 1 AND 2, 2003, 4851 :89-100
[6]   An overview of the performance and scientific results from the Chandra X-ray Observatory [J].
Weisskopf, MC ;
Brinkman, B ;
Canizares, C ;
Garmire, G ;
Murray, S ;
Van Speybroeck, LP .
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 2002, 114 (791) :1-24