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arXiv · 1308.3560

UV-excess sources with a red/IR-counterpart: low-mass companions, debris disks and QSO selection

Kars Verbeek·Paul J. Groot·Simone Scaringi·Jorge Casares·Jesus M. Corral-Santana·Niall Deacon·Janet E. Drew·Boris T. Gänsicke·Eduardo González-Solares·Robert Greimel·Ulrich Heber·Ralf Napiwotzki·Roy H. Østensen·Danny Steeghs·Nicholas J. Wright·Albert Zijlstra
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Abstract

We present the result of the cross-matching between UV-excess sources selected from the UV-excess survey of the Northern Galactic Plane (UVEX) and several infrared surveys (2MASS, UKIDSS and WISE). From the position in the (J-H) vs. (H-K) colour-colour diagram we select UV-excess candidate white dwarfs with an M-dwarf type companion, candidates that might have a lower mass, brown-dwarf type companion, and candidates showing an infrared-excess only in the K-band, which might be due to a debris disk. Grids of reddened DA+dM and sdO+MS/sdB+MS model spectra are fitted to the U,g,r,i,z,J,H,K photometry in order to determine spectral types and estimate temperatures and reddening. From a sample of 964 hot candidate white dwarfs with (g-r)<0.2, the spectral energy distribution fitting shows that ~2-4% of the white dwarfs have an M-dwarf companion, ~2% have a lower-mass companion, and no clear candidates for having a debris disk are found. Additionally, from WISE 6 UV-excess sources are selected as candidate Quasi-Stellar Objects (QSOs). Two UV-excess sources have a WISE IR-excess showing up only in the mid-IR W3 band of WISE, making them candidate Luminous InfraRed Galaxies (LIRGs) or Sbc star-burst galaxies.

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Kars Verbeek, Paul J. Groot, Simone Scaringi, Jorge Casares, Jesus M. Corral-Santana, Niall Deacon, Janet E. Drew, Boris T. Gänsicke, Eduardo González-Solares, Robert Greimel, Ulrich Heber, Ralf Napiwotzki, Roy H. Østensen, Danny Steeghs, Nicholas J. Wright, Albert Zijlstra. 2013-08-16. UV-excess sources with a red/IR-counterpart: low-mass companions, debris disks and QSO selection. https://doi.org/10.1093/mnras%2Fstt1492

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