Spitzer 70-micron Source Counts in GOODS-North
Abstract
We present ultra-deep Spitzer 70-micron observations of GOODS-North. For the first time, the turn-over in the 70-micron Euclidean-normalized differential source counts is observed. We derive source counts down to a flux density of 1.2mJy. From the measured source counts and fluctuation analysis, we estimate a power-law approximation of the faint 70-micron source counts of dN/dS proportional to S^{-1.6}, consistent with that observed for the faint 24-micron sources. An extrapolation of the 70-micron source counts to zero flux density implies a total extragalactic background light (EBL) of 7.4+/-1.9 nW m^{-2} sr^{-1}. The source counts above 1.2mJy account for about 60% of the estimated EBL. From fluctuation analysis, we derive a photometric confusion level of sigma_c = 0.30+/-0.15 mJy (q=5) for the Spitzer 70-micron band.
Cite
@article{arxiv.astro-ph/0606676,
title = {Spitzer 70-micron Source Counts in GOODS-North},
author = {D. T. Frayer and M. T. Huynh and R. Chary and M. Dickinson and D. Elbaz and D. Fadda and J. A. Surace and H. I. Teplitz and L. Yan and B. Mobasher},
journal= {arXiv preprint arXiv:astro-ph/0606676},
year = {2009}
}
Comments
6 pages including 2 figures and 1 table. Accepted ApJ Letters