Published by
EDP Sciences
EDP Sciences Journals List
Subscriber Authentication Point
Home All issues Volume 405/ 3 Article
Free access
Issue A&A
Volume 405, Number 3, July III 2003
Page(s) 833 - 849
Section Extragalactic astronomy
DOI http://dx.doi.org/10.1051/0004-6361:20030661



A&A 405, 833-849 (2003)
DOI: 10.1051/0004-6361:20030661

A deep 6.7 ${{\mu}}$m survey in the SSA13 field with ISO

Y. Sato1, 2, K. Kawara2, L. L. Cowie3, Y. Taniguchi4, D. B. Sanders3, 5, H. Matsuhara1, H. Okuda6, K. Wakamatsu7, Y. Sofue2, R. D. Joseph3 and T. Matsumoto1

1  Institute of Space and Astronautical Science (ISAS), 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan
2  Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015, Japan
3  Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
4  Astronomical Institute, Graduate School of Science, Tohoku University, Aramaki, Aoba, Sendai 980-8578, Japan
5  Max-Planck Institut fur Extraterrestrische Physik, 85740 Garching, Germany
6  Gunma Astronomical Observatory, 6860-86 Nakayama, Takayama, Agatsuma, Gunma 377-0702, Japan
7  Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan

(Received 29 August 2001 / Accepted 18 April 2003 )

Abstract
We present results of a deep mid-infrared survey in the SSA13 field with the Infrared Space Observatory (ISO). In order to probe the near-infrared light at high redshifts, we surveyed the field with the broad band LW2 (5-8.5 ${{\mu}}$m) filter of the mid-infrared camera ISOCAM. Adopting a highly redundant imaging strategy for the 23 h observation and carefully treating gradual changes in the detector responsivity caused by a very high rate of cosmic ray impacts, we succeeded in reaching an 80% completeness limit of 16 ${{\mu}}$Jy in the central 7 arcmin 2 region. Utilizing the signal-to-noise ratio map, we detected 65 sources down to 6 ${{\mu}}$Jy in the 16 arcmin 2 field. Integral galaxy number counts at 6.7 ${{\mu}}$m are then derived, reaching $1.3\times10^4$ deg -2 at the faint limit with a slope of  -1.6 between 13 ${{\mu}}$Jy and 130 ${{\mu}}$Jy. Integrating individual sources in this flux range, the resolved fraction of the extragalactic background light at 6.7 ${{\mu}}$m is estimated to be 0.56 nW m -2 sr -1. These results, which reach a flux limit three times fainter than those in the Hubble Deep Fields, are in fairly good agreement with a model prediction by Franceschini et al. (1997). Finally, we discuss the relation of distant massive E/S0 galaxies to the faint 6.7 ${{\mu}}$m galaxy population.


Key words: Galaxy: evolution -- infrared: galaxies -- cosmology: observations -- surveys -- galaxies: photometry -- methods: data analysis

Offprint request: Y. Sato, ysato@ioa.s.u-tokyo.ac.jp

SIMBAD Objects



© ESO 2003

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.