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Current cosmic microwave background (CMB) bounds on the sum of the neutrino masses assume a sudden reionization scenario described by a single parameter that determines the onset of reionization. We i...
Extrapolating the Evolution of Galaxy Sizes to the Epoch of Reionization
galaxies evolution formation high-redshift cosmology theory
2010/11/16
We use data on the high-redshift evolution of the size distribution and luminosity function of galaxies to constrain the relationship between their star formation eciency and starburst lifetime. Base...
HST SpectralObservations near the He II Ly-alpha Break: Implications for He II Reionization
galaxies active intergalactic medium quasars general ultraviolet galaxies
2010/11/12
Quasars that allow the study of IGM He II are very rare, since they must be at high redshift along sightlines free of substantial hydrogen absorption, but recent work has dramatically expanded the num...
Reionization constraints using Principal Component Analysis
dark ages reionization first stars intergalactic medium cosmology
2010/11/12
Using a semi-analytical model developed by Choudhury & Ferrara (2005) we study the observational
constraints on reionization via a principal component analysis (PCA). Assuming
that reionization at z...
Early star-forming galaxies and the reionization of the Universe
Early star-forming galaxies reionization of the Universe
2010/11/10
Star forming galaxies represent a valuable tracer of cosmic history. Recent observational progress with Hubble Space Telescope has led to the discovery and study of the earliest-known galaxies corresp...
GMRT observation towards detecting the Post-reionization 21-cm signal
GMRT the Post-reionization 21-cm signal
2011/1/10
We have analyzed 610 MHz GMRT observations towards detecting the redshifted 21-cm signal from z=1.32. The multi-frequency angular power spectrum C_l(Delta nu) is used to characterize the statistical p...
The lack of intense Lyman~alpha in ultradeep spectra of z=7 candidates in GOODS-S: imprint of reionization?
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/4
We present ultradeep optical spectroscopy obtained with FORS2 on VLT of seven Lyman-break galaxy (LBG) candidates at z>6.5 selected in the GOODS-S field from Hawk-I/VLT and WFC3/HST imaging. For one g...
Reionization of the universe and the photoevaporation of cosmological minihalos
cosmological minihalos Reionization photoevaporation
2009/6/8
Reionization of the universe and the photoevaporation of cosmological minihalos。