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Chasing the Identification of ASCA Galactic Objects (ChIcAGO): An X-Ray Survey of Unidentified Sources in the Galactic Plane. I. Source Sample and Initial Results

Anderson, Gemma E. and Gaensler, B. M. and Kaplan, David L. and Slane, Patrick O. and Muno, Michael P. and Posselt, Bettina and Hong, Jaesub and Murray, Stephen S. and Steeghs, Danny T. H. and Brogan, Crystal L. and Drake, Jeremy J. and Farrell, Sean A. and Benjamin, Robert A. and Chakrabarty, Deepto and Drew, Janet E. and Finley, John P. and Grindlay, Jonathan E. and Lazio, T. Joseph W. and Lee, Julia C. and Mauerhan, Jon C. and van Kerkwijk, Marten H. (2014) Chasing the Identification of ASCA Galactic Objects (ChIcAGO): An X-Ray Survey of Unidentified Sources in the Galactic Plane. I. Source Sample and Initial Results. Astrophysical Journal Supplement Series, 212 (1). Art. No. 13. ISSN 0067-0049. doi:10.1088/0067-0049/212/1/13.

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We present the Chasing the Identification of ASCA Galactic Objects (ChIcAGO) survey, which is designed to identify the unknown X-ray sources discovered during the ASCA Galactic Plane Survey (AGPS). Little is known about most of the AGPS sources, especially those that emit primarily in hard X-rays (2-10 keV) within the F_x ~ 10^(–13) to 10^(–11) erg cm^(–2) s^(–1) X-ray flux range. In ChIcAGO, the subarcsecond localization capabilities of Chandra have been combined with a detailed multiwavelength follow-up program, with the ultimate goal of classifying the >100 unidentified sources in the AGPS. Overall to date, 93 unidentified AGPS sources have been observed with Chandra as part of the ChIcAGO survey. A total of 253 X-ray point sources have been detected in these Chandra observations within 3' of the original ASCA positions. We have identified infrared and optical counterparts to the majority of these sources, using both new observations and catalogs from existing Galactic plane surveys. X-ray and infrared population statistics for the X-ray point sources detected in the Chandra observations reveal that the primary populations of Galactic plane X-ray sources that emit in the F_x ~ 10^(–13) to 10^(–11) erg cm^(–2) s^(–1) flux range are active stellar coronae, massive stars with strong stellar winds that are possibly in colliding wind binaries, X-ray binaries, and magnetars. There is also another primary population that is still unidentified but, on the basis of its X-ray and infrared properties, likely comprises partly Galactic sources and partly active galactic nuclei.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Gaensler, B. M.0000-0002-3382-9558
Kaplan, David L.0000-0001-6295-2881
Brogan, Crystal L.0000-0002-6558-7653
Drake, Jeremy J.0000-0002-0210-2276
Chakrabarty, Deepto0000-0001-8804-8946
Grindlay, Jonathan E.0000-0002-1323-5314
Lazio, T. Joseph W.0000-0002-3873-5497
Additional Information:© 2014 American Astronomical Society. Received 2013 July 2; accepted 2014 February 28; published 2014 April 28. G.E.A. acknowledges the support of an Australian Postgraduate Award. B.M.G. acknowledges the support of an Australian Laureate Fellowship through ARC grant FL100100114. P.O.S. acknowledges partial support from NASA contract NAS8- 03060. D.T.H.S. acknowledges a STFC Advanced Fellowship. J.J.D. was supported by NASA contract NAS8-39073 to the Chandra X-ray Center (CXC). Support for this work was also provided by NASA through Chandra award number GO9-0155X issued by the CXC,which is operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA. The access to major research facilities program is supported by the Commonwealth of Australia under the International Science Linkages program. This research makes use of data obtained with the Chandra X-ray Observatory and software provided by the CXC in the application packages CIAO. The ATCA is part of the Australia Telescope, funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. The MOST is operated with the support of the Australian Research Council and the Science Foundation for Physics within the University of Sydney. Observing time on the 6.5 m Baade Magellan Telescope, located at Las Campanas Observatory, was allocated through the Harvard-Smithsonian Center for Astrophysics and the Massachusetts Institute of Technology. 2MASS is a joint project of the University of Massachusetts and the IPAC/Caltech, funded by NASA and the NFS. GLIMPSE survey data are part of the Spitzer Legacy Program. The Spitzer Space Telescope is operated by JPL/Caltech under a contract with NASA. This research has made use of NASA’s Astrophysics Data System. Facilities: ASCA,ATCA,CXO(ACIS,HRC), CTIO:2MASS, FLWO:2MASS, Magellan:Baade (IMACS, MagIC, PANIC), Molonglo Observatory, Spitzer, VLA, XMM (EPIC)
Funding AgencyGrant Number
Australian Postgraduate AwardUNSPECIFIED
Australian Research CouncilFL100100114
Science and Technology Facilities Council (STFC)UNSPECIFIED
Commonwealth of Australia International Science Linkages ProgramUNSPECIFIED
University of Sydney Science Foundation for PhysicsUNSPECIFIED
Subject Keywords:surveys; X-rays: binaries; X-rays: galaxies; X-rays: general; X-rays: stars
Issue or Number:1
Record Number:CaltechAUTHORS:20140821-095351158
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Official Citation:Chasing the Identification of ASCA Galactic Objects (ChIcAGO): An X-Ray Survey of Unidentified Sources in the Galactic Plane. I. Source Sample and Initial Results Gemma E. Anderson et al. 2014 ApJS 212 13
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48769
Deposited By: Ruth Sustaita
Deposited On:21 Aug 2014 17:41
Last Modified:10 Nov 2021 18:35

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