Spatial correlation between submillimetre and Lyman-alpha galaxies in the SSA 22 protocluster

Y Tamura
K Kohno
K Nakanishi
B Hatsukade
D Iono
GW Wilson
Min Yun, University of Massachusetts - Amherst
T Takata
Y Matsuda
T Tosaki
H Ezawa
TA Perera
KS Scott
JE Austermann
DH Hughes
I Aretxaga
A Chung
T Oshima
N Yamaguchi
K Tanaka
R Kawabe

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This is the pre-published version harvested from ArXiv. The published version is located at http://www.nature.com/nature/journal/v459/n7243/abs/nature07947.html

Abstract

Lyman- emitters are thought to be young, low-mass galaxies with ages of 10⁸ yr (refs 1, 2). An overdensity of them in one region of the sky (the SSA 22 field) traces out a filamentary structure in the early Universe at a redshift of z 3.1 (equivalent to 15 per cent of the age of the Universe) and is believed to mark a forming protocluster^{3, 4}. Galaxies that are bright at (sub)millimetre wavelengths are undergoing violent episodes of star formation^{5, 6, 7, 8}, and there is evidence that they are preferentially associated with high-redshift radio galaxies⁹, so the question of whether they are also associated with the most significant large-scale structure growing at high redshift (as outlined by Lyman- emitters) naturally arises. Here we report an imaging survey of 1,100-m emission in the SSA 22 region. We find an enhancement of submillimetre galaxies near the core of the protocluster, and a large-scale correlation between the submillimetre galaxies and the low-mass Lyman- emitters, suggesting synchronous formation of the two very different types of star-forming galaxy within the same structure at high redshift. These results are in general agreement with our understanding of the formation of cosmic structure.