dc.contributor.author | Anderson, Scott | |
dc.contributor.author | Voges, Wolfgang | |
dc.contributor.author | Margon, Bruce | |
dc.contributor.author | Trumper, Joachim | |
dc.contributor.author | Agueros, Marcel | |
dc.contributor.author | Boller, Thomas | |
dc.contributor.author | Collinge, Matthew | |
dc.contributor.author | Homer, Lee | |
dc.contributor.author | Stinson, Gregory | |
dc.contributor.author | Strauss, Michael | |
dc.contributor.author | Annis, James | |
dc.contributor.author | Gomez, Percy | |
dc.contributor.author | Hall, Patrick | |
dc.contributor.author | Nichol, Robert | |
dc.contributor.author | Richards, Gordon | |
dc.contributor.author | Schneider, Donald | |
dc.contributor.author | Vanden Berk, Daniel | |
dc.contributor.author | Fan, Xiaohui | |
dc.contributor.author | Ivezic, Zeljko | |
dc.contributor.author | Munn, Jeffrey | |
dc.contributor.author | Newberg, Heidi Jo | |
dc.contributor.author | Richmond, Michael | |
dc.contributor.author | Weinberg, David | |
dc.contributor.author | Yanny, Brian | |
dc.contributor.author | Bahcall, Neta | |
dc.contributor.author | Brinkmann, Jonathan | |
dc.contributor.author | Fukugita, Masataka | |
dc.contributor.author | York, Donald | |
dc.date.accessioned | 2008-11-19T15:36:10Z | |
dc.date.available | 2008-11-19T15:36:10Z | |
dc.date.issued | 2003-11 | |
dc.identifier.citation | The Astronomical Journal 126 (2003) 2209-2229 | en_US |
dc.identifier.uri | http://hdl.handle.net/1850/7547 | |
dc.description | RIT community members may access full-text via RIT Libraries licensed databases: http://library.rit.edu/databases/ | |
dc.description.abstract | Many open questions in X-ray astronomy are limited by the relatively small number
of objects in uniform optically-identified and observed samples, especially when rare
subclasses are considered, or when subsets are isolated to search for evolution or
correlations between wavebands. We describe initial results of a new program aimed
to ultimately yield 104 fully characterized X-ray source identifications—a sample about an order of magnitude larger than earlier efforts. The technique is detailed, and
employs X-ray data from the ROSAT All-Sky Survey (RASS), and optical imaging and
spectroscopic follow-up from the Sloan Digital Sky Survey (SDSS); these two surveys
prove to be serendipitously very well matched in sensitivity. As part of the SDSS
software pipelines, optical objects in the SDSS photometric catalogs are automatically
positionally cross-correlated with RASS X-ray sources. Then priorities for follow-on
SDSS optical spectra of candidate counterparts are automatically assigned using an
algorithm based on the known ratios of fx/fopt for various classes of X-ray emitters
at typical RASS fluxes of 10−13 erg cm−2 s−1. SDSS photometric parameters for
optical morphology, magnitude, colors, plus FIRST radio information, serve as proxies
for object class.
Initial application of this approach to RASS/SDSS data from 1400 deg2 of sky
provides a catalog of more than 1200 spectroscopically confirmed quasars and other
AGN that are probable RASS identifications. Most of these are new identifications,
and only a few percent of the AGN counterparts are likely to be random superpositions.
The magnitude and redshift ranges of the counterparts are very broad, extending over
15 < m < 21 and 0.03 < z < 3.6, respectively. Although most identifications are
quasars and Seyfert 1s, a variety of other AGN subclasses are also sampled. Substantial
numbers of rare AGN types are found, including more than 130 narrow-line Seyfert 1s
and 45 BL Lac candidates. These early results already provide a very sizeable
set of source identifications, demonstrate utility of the sample in multi-waveband
investigations, and show the capability of the joint RASS/SDSS approach to efficiently
proceed towards the largest homogeneously selected/observed sample of X-ray emitting
quasars and other kinds of AGN. | en_US |
dc.language.iso | en_US | en_US |
dc.publisher | American Astronomical Society - The Astronomical Journal | en_US |
dc.relation.ispartofseries | vol. 126 | en_US |
dc.relation.ispartofseries | no. 5 | en_US |
dc.relation.ispartofseries | pps. 2209-2229 | en_US |
dc.subject | Catalogs - surveys | en_US |
dc.subject | Quasars - general | en_US |
dc.subject | Quasars - individual | en_US |
dc.subject | X-rays | en_US |
dc.title | A large, uniform sample of X-ray emitting AGN: selection approach and an initial catalog from the ROSAT All-Sky and Sloan Digital Sky Surveys | en_US |
dc.type | Article | en_US |
dc.identifier.url | http://dx.doi.org/10.1086/378999 | |