Astro Seminar

Date: 
10/12/2022 - 3:00pm
Location: 
CP179 and on zoom
Speaker(s) / Presenter(s): 
John Pritchard (UL)
Type of Event (for grouping events):

THE GALEX EXTRAGALACTIC SPECTRA DATA BASE

Abstract: 
 
We have matched objects in the Galaxy Evolution Explorer (GALEX) spectroscopic fields with publicly available ultraviolet, optical, and infrared surveys, to construct a photometric and spectroscopic catalog for non-stellar objects with GALEX spectroscopic counterparts. Of the total sample of GALEX spectra recorded in the database, approximately 20\% are determined to reliably correspond to non-stellar objects. These objects have been cross-matched with SDSS, WISE, and 2MASS photometric and spectroscopic survey catalogs, and VISTA and UKIRT near-IR catalogs where available, to construct spectral energy distributions (SED's) from the GALEX-FUV to WISE-w4 magnitudes for all non-stellar objects within the fields. Analysis of 209 fields with at least one object matched in SDSS give a total of 12,020 extragalactic objects, comprising 1974 known QSOs and AGNs, 2274 star-forming galaxies, 6327 quiescent spiral galaxies, and 386 elliptical galaxies.