Related papers: A Fast Method for Power Spectrum and Foreground An…
We describe a new technique for constraining the radio loud population of active galactic nuclei at high redshift by measuring the imprint of 21 cm spectral absorption features (the 21 cm forest) on the 21 cm power spectrum. Using…
The radio interferometric closure phases can be a valuable tool for studying cosmological {H\scriptsize{I}}~from the early Universe. Closure phases have the advantage of being immune to element-based gains and associated calibration errors.…
The redshifted cosmic 21 cm line signal of neutral hydrogen provides the possibility to constrain the matter power spectrum. Cross correlating temperature maps at different frequencies (corresponding to different redshifts along the line of…
Recent theoretical developments for observing the Epoch of Reionization (EOR) have concentrated on the power spectrum signature of redshifted 21 cm emission. These studies have demonstrated the great potential of statistical EOR…
The 21-cm power spectrum (PS) has been shown to be a powerful discriminant of reionization and cosmic dawn astrophysical parameters. However, the 21-cm tomographic signal is highly non-Gaussian. Therefore there is additional information…
The fluctuations in the dark matter-baryon relative velocity field are imprinted as acoustic oscillations in the 21-cm power spectrum during cosmic dawn (CD). These velocity acoustic oscillations (VAOs) keep the imprints of the comoving…
The 21 cm hyperfine transition of neutral hydrogen offers a promising probe of the large scale structure of the universe before and during the Epoch of Reionization, when the first ionizing sources formed. Bright radio emission from…
The X-ray background during the epoch of reionization is currently poorly constrained. We demonstrate that it is possible to use first generation 21 cm experiments to calibrate it. Using the semi-numerical simulation, 21cmFAST, we calculate…
In measuring the power spectrum of the distribution of large numbers of dark matter particles in simulations, or galaxies in observations, one has to use Fast Fourier Transforms (FFT) for calculational efficiency. However, because of the…
Observation of the 21cm line signal from neutral hydrogen during the Epoch of Reionization is challenging due to extremely bright Galactic and extragalactic foregrounds and complicated instrumental calibration. A reasonable approach for…
Studies of the cosmic dark ages ($30 \lesssim z \lesssim 150$) using the highly redshifted 21 cm line of neutral hydrogen offer unparalleled amounts of cosmological information, and recent years have seen the refinement of concepts for such…
Massive neutrinos modify the expansion history of the universe and suppress the structure formation below their free streaming scale. Cosmic microwave background (CMB) observations at small angular scales can be used to constrain the total…
The 21\,cm transition of neutral hydrogen is opening an observational window into the cosmic dawn of the universe---the epoch of first star formation. We use 28\,hr of data from the Owens Valley Radio Observatory Long Wavelength Array…
We estimate CMB polarization and temperature power spectra using WMAP 5-year foreground contaminated maps. The power spectrum is estimated by using a model independent method, which does not utilize directly the diffuse foreground templates…
Experiments aimed at detecting highly-redshifted 21 centimeter emission from the Epoch of Reionization (EoR) are plagued by the contamination of foreground emission. A potentially important source of contaminating foregrounds may be…
We develop a pseudo power spectrum technique for measuring the lensing power spectrum from weak lensing surveys in both the full sky and flat sky limits. The power spectrum approaches have a number of advantages over the traditional…
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…
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…
We present a method for subtracting point sources from interferometric radio images via forward modeling of the instrument response and involving an algebraic nonlinear minimization. The method is applied to simulated maps of the Murchison…
We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes…