相关论文: Does Planck 2015 polarization favor high redshift …
We propose a hybrid quadratic estimator to measure cross correlations between gravitational lensing of the cosmic microwave background (CMB) and differential screening effects arising from fluctuations in the electron column density, such…
There is growing interest in using 3-dimensional neutral hydrogen mapping with the redshifted 21 cm line as a cosmological probe, as it has been argued to have a greater long-term potential than the cosmic microwave background. However, its…
The Thomson scattering optical depth to reionisation, $\tau$, one of the six parameters of the $\Lambda$CDM model, is primarily constrained by the large-scale E-mode polarisation of the Cosmic Microwave Background (CMB). In this work, we…
The James Webb Space Telescope (JWST) has observed massive galaxies at high redshifts, which implies an earlier epoch of reionization (EoR) compared with the cosmic microwave background (CMB) results. In this paper, based on \texttt{Planck…
We investigate the dependence of the epoch of reionization on the properties of cosmological perturbations, in the context of cosmologies permitted by WMAP. We compute the redshift of reionization using a simple model based on the…
Recent results of ground-based telescopes, giving high-quality measurements of the CMB temperature power spectrum on small scales motivate the need for an accurate model of foregrounds, which dominate the primary signal at these multipoles.…
We present measurements of polarization lensing using the 150 GHz maps which include all data taken by the BICEP2 & Keck Array CMB polarization experiments up to and including the 2014 observing season (BK14). Despite their modest angular…
We use Bayesian model selection tools to forecast the Planck satellite's ability to distinguish between different models for the reionization history of the Universe, using the large angular scale signal in the cosmic microwave background…
We analyze BICEP2 and Planck data using a model that includes CMB lensing, gravity waves, and polarized dust. Planck dust polarization maps have highlighted the difficulty of estimating the dust polarization in low intensity regions,…
Future arcminute resolution polarization data from ground-based Cosmic Microwave Background (CMB) observations can be used to estimate the contribution to the temperature power spectrum from the primary anisotropies and to uncover the…
We analyze the Ly alpha forest properties of a sample of 15 high redshift quasars lying between z = 4.42 and z = 5.75, using high signal-to-noise spectra obtained with ESI on the Keck II 10 m telescope. The distribution of transmissions in…
We present a comparison between several observational tests of the post-reionization IGM and the numerical simulations of reionization completed under the Cosmic Reionization On Computers (CROC) project. The CROC simulations match the gap…
Reducing the power on small scales relative to the `standard' LCDM model alleviates a number of possible discrepancies with observations, and is favored by the recent analysis of WMAP plus galaxy and Lyman-alpha forest data. Here, we…
We present constraints on the cosmological and reionization parameters based on the cumulative mass function of the Ly-alpha systems. We find that the analysis of the cumulative mass function of the Ly-alpha systems indicates a reionization…
One of the main problems for extracting the Cosmic Microwave Background (CMB) from submm/mm observations is to correct for the Galactic components, mainly synchrotron, free - free and thermal dust emission with the required accuracy.…
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…
Recent years have brought strong observational evidences for the standard LCDM cosmological model. Cosmic microwave background (CMB) anisotropy and large scale structure (LSS) probes do not favour any extensions of the standard model.…
We point out that polarization measurements as planned for the upcoming PLANCK mission can significantly enhance the accuracy of cosmic parameter estimation compared to the temperature anisotropy spectrum alone. In order to illustrate this,…
CII is one of the brightest emission lines from star-forming galaxies and is an excellent tracer for star formation. Recent work measured the CII emission line amplitude for redshifts $2<z<3.2$ by cross-correlating Planck High Frequency…
Based on a new sample of 355 quasars with significant optical polarization and using complementary statistical methods, we confirm that quasar polarization vectors are not randomly oriented over the sky with a probability often in excess of…