English

Probable detection of HI at $z\simeq 1.3$ from DEEP2 galaxies using the GMRT

Cosmology and Nongalactic Astrophysics 2013-05-20 v1

Abstract

We have observed the DEEP2 galaxies using the Giant Meterwave Radio Telescope in the frequency band of 610 MHz. There are 400\simeq 400 galaxies in the redshift range 1.24<z<1.361.24 < z < 1.36 and within the field of view 44\simeq 44', of the GMRT dishes. We have coadded the HI 21 cm-line emissions at the locations of these DEEP2 galaxies. We apply stacking on three different data cubes: primary beam uncorrected, primary beam corrected (uniform weighing ) and primary beam corrected (optimal weighing). We obtain a peak signal strength in the range 825μ8\hbox{--}25 \, \rm \muJy/beam for a velocity width in the range 270810kmsec1270\hbox{--} 810 \, \rm km \, sec^{-1}. The error on the signal, computed by bootstrapping, lies in the range 2.56μ2.5\hbox{--}6 \, \rm \muJy/beam, implying a 2.5--4.7-σ\sigma detection of the signal at z1.3z \simeq 1.3. We compare our results with N-body simulations of the signal at z1z\simeq 1 and find reasonable agreement. We also discuss the impact of residual continuum and systematics.

Keywords

Cite

@article{arxiv.1305.4017,
  title  = {Probable detection of HI at $z\simeq 1.3$ from DEEP2 galaxies using the GMRT},
  author = {Shiv K. Sethi and K. S. Dwarakanath and Chandrashekar Murugesan},
  journal= {arXiv preprint arXiv:1305.4017},
  year   = {2013}
}

Comments

24 pages, 6 figures