Computer Science – Graphics
Scientific paper
Jan 2012
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012aas...21924304a&link_type=abstract
American Astronomical Society, AAS Meeting #219, #243.04
Computer Science
Graphics
Scientific paper
Discoveries from Chandra, Spitzer and SDSS have revealed a substantial population of luminous dust-obscured quasars. It is now apparent that quasar demographics based on optically bright objects are missing a substantial fraction of the quasar population; at low redshifts (z < 0.8), SDSS studies have shown that of order half of all high-luminosity quasars are obscured. Many obscured quasars have narrow-line regions illuminated by the central engine, and thus are recognized from their emission-line ratios as excited by an accreting black hole.
A search for quasars at z>1 with narrow lines from SDSS-I/II turned up high-redshift analogues to Narrow-Line Seyfert 1 galaxies. But BOSS includes substantially lower-luminosity objects at all redshifts. This project is to explore the emission-line width distribution of quasars in BOSS, specifically with the goal of finding examples of obscured quasars at high redshift. Preliminary examination found a population of 207 strong candidates at redshifts 1.55 < z < 4.22. All objects have FWHM < 2100 km/s and have high equivalent width lines for the CIV line (1549A) and Lyman-alpha line (1216A). We are currently using NIR spectroscopy (to look at the [OIII], H-alpha and H-beta lines) on the Apache Point Observatory 3.5m telescope in an attempt to examine several of our candidates for a broad component to the Balmer lines, the luminosity of [OIII], a proxy for the intrinsic bolometric luminosity of the objects, and the continuum slope at rest-frame 5000A to constrain the stellar population and stellar masses of host galaxies. Future plans include higher resolution NIR spectroscopy and spectroplarimetry (to look for evidence of a scattered broad-line region) of our candidates as well as comparison to existing data sets such as FIRST, WISE, and UKIDSS.
Alexandroff Rachael
Greene Joshua
Strauss Michael
Zakamska Nadia
No associations
LandOfFree
Searching for High-Redshift Obscured Quasars in the Sloan Digital Sky Survey (SDSS) Baryonic Oscillation Spectroscopic Survey (BOSS) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Searching for High-Redshift Obscured Quasars in the Sloan Digital Sky Survey (SDSS) Baryonic Oscillation Spectroscopic Survey (BOSS), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Searching for High-Redshift Obscured Quasars in the Sloan Digital Sky Survey (SDSS) Baryonic Oscillation Spectroscopic Survey (BOSS) will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1578691