Classification and Characterization of Objects from GALEX and SDSS surveys

Luciana Bianchi; M. Seibert; W. Zheng; D. Thilker; P. Friedman; T. Wyder; J. Donas; T. Barlow; Yong-Ik Byun; K. Forster; T. Heckman; P. Jelinsky; Y. -W. Lee; B. Madore; R. Malina; C. Martin; B. Milliard; P. Morrissey; S. Neff; M. Rich; D. Schiminovich; O. Siegmund; T. Small; A. Szalay; B. Welsh

arXiv · astro-ph/0411406

Classification and Characterization of Objects from GALEX and SDSS surveys

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Abstract

We use the GALEX (Galaxy Evolution Explorer) Medium Imaging Survey (MIS) and All-Sky Imaging Survey (AIS) data available in the first internal release, matched to the SDSS catalogs in the overlapping regions, to classify objects by comparing the multi-band photometry to model colors. We show an example of the advantage of such broad wavelength coverage (GALEX far-UV and near-UV, SDSS ugriz) in classifying objects and augmenting the existing samples and catalogs. From the MIS [AIS] sample over an area of 75 [92] square degrees, we select a total of 1736 [222] QSO candidates at redshift less than 2, significantly extending the number of fainter candidates, and moderately increasing the number of bright objects in the SDSS list of spectroscopically confirmed QSO. Numerous hot stellar objects are also revealed by the UV colors, as expected.

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Luciana Bianchi, M. Seibert, W. Zheng, D. Thilker, P. Friedman, T. Wyder, J. Donas, T. Barlow, Yong-Ik Byun, K. Forster, T. Heckman, P. Jelinsky, Y. -W. Lee, B. Madore, R. Malina, C. Martin, B. Milliard, P. Morrissey, S. Neff, M. Rich, D. Schiminovich, O. Siegmund, T. Small, A. Szalay, B. Welsh. 2004-11-15. Classification and Characterization of Objects from GALEX and SDSS surveys. https://arxiv.org/abs/astro-ph/0411406

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