Starburst galaxies and structure in the submillimetre background towards the Hubble Deep Field
J. A. Peacock, M. Rowan-Robinson, A. W. Blain, J. S. Dunlop, A. Efstathiou, D. H. Hughes, T. Jenness, R. J. Ivison, A. Lawrence, M. S. Longair, R. G. Mann, S. J. Oliver, S. Serjeant;
MNRAS, 2000, 318, 535
ABSTRACT:We use an 850-μm SCUBA map of the Hubble Deep Field (HDF) to study the dust properties of optically-selected starburst galaxies at high
redshift.
The optical/infrared (IR) data in the HDF allow a photometric redshift to
be estimated for each galaxy, together with an estimate of the visible
star-formation rate.
The 850-μm flux density of each source provides the
complementary information: the amount of hidden, dust-enshrouded star formation
activity.
Although the 850-μm map does not allow detection of the majority of
individual sources, we show that the galaxies with the highest UV star-formation
rates are detected statistically, with a flux density of about
S850=0.2mJy for an apparent UV star-formation rate of
1h-2Msolaryr-1.
This level of submillimetre output indicates that the total star-forming
activity is on average a factor of approximately 6 times larger than the rate
inferred from the UV output of these galaxies.
The general population of
optical starbursts is then predicted to contribute at least 25per cent of the
850-μm background.
We carry out a power-spectrum analysis of the map, which
yields some evidence for angular clustering of the background source
population, but at a level lower than that seen in Lyman-break galaxies.
Together
with other lines of argument, particularly from the NICMOS HDF data, this
suggests that the 850-μm background originates over an extremely wide range
of redshifts - perhaps 1<~z<~6.
KEYWORDS: galaxies: evolution, galaxies: starburst, cosmology: observations
CODE: peacock2000