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تسجيل مستخدم جديدProbable detection of HI at $zsimeq 1.3$ from DEEP2 galaxies using the GMRT
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We have observed the DEEP2 galaxies using the Giant Meterwave Radio Telescope in the frequency band of 610 MHz. There are $simeq 400$ galaxies in the redshift range $1.24 < z < 1.36$ and within the field of view $simeq 44$, 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 $8hbox{--}25 , rm mu$Jy/beam for a velocity width in the range $270hbox{--} 810 , rm km , sec^{-1}$. The error on the signal, computed by bootstrapping, lies in the range $2.5hbox{--}6 , rm mu$Jy/beam, implying a 2.5--4.7-$sigma$ detection of the signal at $z simeq 1.3$. We compare our results with N-body simulations of the signal at $zsimeq 1$ and find reasonable agreement. We also discuss the impact of residual continuum and systematics.
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