Related papers: Redshift space 21 cm power spectra from reionizati…
We present detailed predictions for the redshifted 21cm signal from the epoch of reionization. These predictions are obtained from radiative transfer calculations on the results of large scale (100/h Mpc), high dynamic range, cosmological…
We present spatially-resolved spectroscopic observations of 10 isolated Galactic HII regions using data from the LAMOST Medium-Resolution Spectroscopic Survey of Nebulae (LAMOST MRS-N). The high spatial resolution of the data allows us to…
Foreground subtraction is the biggest challenge for future redshifted 21 cm observations to probe reionization. We use a short GMRT observation at 153 MHz to characterize the statistical properties of the background radiation across ~ one…
We study the detectability of the cross-correlation between 21 cm emission from the intergalactic medium and the galaxy distribution during (and before) reionization. We show that first-generation 21 cm experiments, such as the Mileura…
The reionization process is driven by ionizing photons from dwarf galaxies in halos with virial temperature $T_{\rm vir} \gtrsim 10^4$ K, while minihalos whose $T_{\rm vir}\lesssim 10^4$ K consume ionizing photons and have negative…
We explore features of redshift distortion in Fourier analysis of N-body simulations. The phases of the Fourier modes of the dark matter density fluctuation are generally shifted by the peculiar motion along the line of sight, the induced…
Radio interferometers, such as the Low-Frequency Array and the future Square Kilometre Array, are attempting to measure the spherically averaged 21-cm power spectrum from the Epoch of Reionization. Understanding of the dominant physical…
In the coming decade, low-frequency radio arrays will begin to probe the epoch of reionization via the redshifted 21-cm hydrogen line. Successful interpretation of these observations will require effective statistical techniques for…
We present measurements of the large-scale (~40 comoving Mpc) effective optical depth of HeII Ly$\alpha$ absorption, $\tau_{\rm eff}$, at 2.54<z<3.86 toward 16 HeII-transparent quasars observed with the Cosmic Origins Spectrograph (COS) on…
After reionization, emission in the 21 cm hyperfine transition provides a direct probe of neutral hydrogen distributed in galaxies. Different from galaxy redshift surveys, observation of baryon acoustic oscillations in the cumulative 21 cm…
Using the CoDa II simulation, we study the Ly$\alpha$ transmissivity of the intergalactic medium (IGM) during reionization. At $z>6$, a typical galaxy without an active galactic nucleus fails to form a proximity zone around itself due to…
HII regions made of gas ionized by radiations from young massive stars, are widely distributed in the Milky Way. They are tracers for star formation, and their distributions are correlated with the Galactic spiral structure. Radio…
The 21 cm brightness temperature during the Epoch of Reionisation is widely modelled using semi-numeric simulations, used for their computational speed and flexibility in testing astrophysical and cosmological parameters. However, it is…
Upon an expansion of all of the searches for redshifted HI 21-cm absorption (0.0021 < z 5.19), we update recent results regarding the detection of 21-cm in the non-local Universe. Specifically, we confirm that photo-ionisation of the gas is…
21cm emission from residual neutral hydrogen after the epoch of reionization can be used to trace the cosmological power spectrum of density fluctuations. Using a Fisher matrix formulation, we provide a detailed forecast of the constraints…
Low-frequency radio observations of neutral hydrogen during and before the epoch of cosmic reionization will provide hundreds of quasi-independent source planes, each of precisely known redshift, if a resolution of ~ 1 arcminutes or better…
The 21-cm PDF (i.e., distribution of pixel brightness temperatures) is expected to be highly non-Gaussian during reionization and to provide important information on the distribution of density and ionization. We measure the 21-cm PDF as a…
Initial density distribution provides a basis for understanding the complete evolution of cosmological density fluctuations. While reconstruction in our local Universe exploits the observations of galaxy surveys with large volumes,…
We study statistics of the 21-cm signal from the epoch of reionization. We propose to use [OIII] line emitting galaxies to cross-correlate with the 21-cm signal from $z = 7 - 10$. To this aim, we employ simulations of reionization obtained…
We investigate the possibility of detecting the 3D cross correlation power spectrum of the Ly-$\alpha$ forest and HI 21 cm signal from the post reionization epoch. The cross-correlation signal is directly dependent on the dark matter power…