ausblenden:
Schlagwörter:
Astrophysics, Galaxy Astrophysics, astro-ph.GA,Astrophysics, Cosmology and Extragalactic Astrophysics, astro-ph.CO
MPINP:
Infrarot-Astrophysik - Abteilung Hofmann
Zusammenfassung:
The Galaxy And Mass Assembly (GAMA) survey furnishes a deep redshift catalog
that, when combined with the Wide-field Infrared Explorer ($WISE$), allows us
to explore for the first time the mid-infrared properties of $> 110, 000$
galaxies over 120 deg$^2$ to $z\simeq 0.5$. In this paper we detail the
procedure for producing the matched GAMA-$WISE$ catalog for the G12 and G15
fields, in particular characterising and measuring resolved sources; the
complete catalogs for all three GAMA equatorial fields will be made available
through the GAMA public releases. The wealth of multiwavelength photometry and
optical spectroscopy allows us to explore empirical relations between optically
determined stellar mass (derived from synthetic stellar population models) and
3.4micron and 4.6micron WISE measurements. Similarly dust-corrected
Halpha-derived star formation rates can be compared to 12micron and 22micron
luminosities to quantify correlations that can be applied to large samples to
$z<0.5$. To illustrate the applications of these relations, we use the 12micron
star formation prescription to investigate the behavior of specific star
formation within the GAMA-WISE sample and underscore the ability of WISE to
detect star-forming systems at $z\sim0.5$. Within galaxy groups (determined by
a sophisticated friends-of-friends scheme), results suggest that galaxies with
a neighbor within 100$\,h^{-1} $kpc have, on average, lower specific star
formation rates than typical GAMA galaxies with the same stellar mass.
