Detectability of the 21 cm-CMB cross-correlation from the EoR (2009)
Tashiro, Hiroyuki, Aghanim, Nabila, Langer, Mathieu, Douspis, Marian, Zaroubi, Saleem, Jelic, Vibor
The 21-cm line fluctuations and the cosmic microwave background (CMB) are powerful probes of the epoch of reionisation of the universe. We study the potential of the cross-correlation between 21-cm...
Jelic, Vibor, Zaroubi, Saleem, Aghanim, Nabila, Douspis, Marian, Koopmans, Leon V. E., Langer, Mathieu, ...
The Universe's Epoch of Reionization (EoR) can be studied using a number of observational probes that provide complementary or corroborating information. Each of these probes suffers from its own...
Non-parametric foreground subtraction for 21cm epoch of reionization experiments (2009)
Harker, Geraint, Zaroubi, Saleem, Bernardi, Gianni, Brentjens, Michiel A., De Bruyn, A. G., Ciardi, Benedetta, ...
An obstacle to the detection of redshifted 21cm emission from the epoch of reionization (EoR) is the presence of foregrounds which exceed the cosmological signal in intensity by orders of magnitude....
Labropoulos, Panagiotis, Koopmans, Leon V. E., Jelic, Vibor, Yatawatta, Sarod, Thomas, Rajat M., Bernardi, Gianni, ...
A number of experiments are set to measure the 21-cm signal of neutral hydrogen from the Epoch of Reionization (EoR). The common denominator of these experiments are the large data sets produced,...
Fast large-scale reionization simulations (2009)
Thomas, Rajat M., Zaroubi, Saleem, Ciardi, Benedetta, Pawlik, Andreas H., Labropoulos, Panagiotis, Jelic, Vibor, ...
Harker, Geraint J. A., Zaroubi, Saleem, Thomas, Rajat M., Jelic, Vibor, Labropoulos, Panagiotis, Mellema, Garrelt, ...
Non-parametric foreground subtraction for 21-cm epoch of reionization experiments (2009)
Harker, Geraint, Zaroubi, Saleem, Bernardi, Gianni, Brentjens, Michiel A., De Bruyn, A. G., Ciardi, Benedetta, ...
Radio Interferometric Calibration Using The SAGE Algorithm (2008)
Yatawatta, Sarod, Zaroubi, Saleem, De Bruyn, Ger, Koopmans, Leon, Noordam, Jan
Radio Interferometry is an essential method for astronomical observations. Self-calibration techniques have increased the quality of the radio astronomical observations (and hence the science) by...
Harker, Geraint J. A., Zaroubi, Saleem, Thomas, Rajat M., Jelic, Vibor, Labropoulos, Panagiotis, Mellema, Garrelt, ...
Detecting redshifted 21cm emission from neutral hydrogen in the early Universe promises to give direct constraints on the epoch of reionization (EoR). It will, though, be very challenging to extract...
Fast Large-Scale Reionization Simulations (2008)
Thomas, Rajat M., Zaroubi, Saleem, Ciardi, Benedetta, Pawlik, Andreas H., Labropoulos, Panagiotis, Jelic, Vibor, ...
We present an efficient method to generate large simulations of the Epoch of Reionization (EoR) without the need for a full 3-dimensional radiative transfer code. Large dark-matter-only simulations...
Foreground simulations for the LOFAR - Epoch of Reionization Experiment (2008)
Jelic, Vibor, Zaroubi, Saleem, Labropoulos, Panagiotis, Thomas, Rajat M., Bernardi, Gianni, Brentjens, Michiel A., ...
Future high redshift 21-cm experiments will suffer from a high degree of contamination, due both to astrophysical foregrounds and to non-astrophysical and instrumental effects. In order to reliably...
Tashiro, Hiroyuki, Aghanim, Nabila, Langer, Mathieu, Douspis, Marian, Zaroubi, Saleem
The cosmic microwave background (CMB) polarisation and the 21 cm line fluctuations are powerful probes of cosmological reionisation. We study how the cross-correlation between the CMB polarisation...
Large-Scale Power Spectrum and Cosmological Parameters from SFI Peculiar Velocities (2007)
Wolfram Freudling, Idit Zehavi, Avishai Dekel, Amiram Eldar, Riccardo Giovanelli, ...
We estimate the power spectrum of mass density fluctuations from peculiar velocities of galaxies by applying an improved maximum-likelihood technique to the new all-sky SFI catalog. Parametric models...
Time-evolution of ionization and heating around first stars and miniquasars (2007)
Thomas, Rajat M., Zaroubi, Saleem
A one dimensional radiative transfer code is developed to track the ionization and heating pattern around the first miniquasars and Population III stars. The code follows the evolution of the...
Heating of the Intergalactic Medium by Primordial Miniquasars (2006)
Zaroubi, Saleem, Thomas, Rajat M., Sugiyama, Naoshi, Silk, Joe
A simple analytical model is used to calculate the X-ray heating of the IGM for a range of black hole masses. This process is efficient enough to decouple the spin temperature of the intergalactic...
LOFAR as a Probe of the Sources of Cosmological Reionisation (2004)
We propose use of the thickness of the ionisation front as a discriminant between alternative modes of reionisation in the early universe, by stars or by miniquasars. Assuming a...
Zaroubi, Saleem, Branchini, Enzo
We introduce a simple linear equation relating the line-of-sight peculiar velocity and density contrast correlation functions. The relation, which we call the "Gaussian cell two-point energy-like...
The 2dF Galaxy Redshift Survey: Wiener reconstruction of the cosmic web (2004)
Erdogdu, Pirin, Lahav, Ofer, Zaroubi, Saleem, Efstathiou, George P., Moody, Stephen J., Peacock, John A., ...
We reconstruct the underlying density field of the Two-degree Field Galaxy Redshift Survey (2dFGRS) for the redshift range 0.035 < z < 0.200 using the Wiener filtering method. The Wiener filter...
The 2dF Galaxy Redshift Survey: Wiener reconstruction of the cosmic web (2004)
Erdogdu, Pirin, Lahav, Ofer, Zaroubi, Saleem, Efstathiou, George P., Moody, Stephen J., Peacock, John A., ...
We reconstruct the underlying density field of the Two-degree Field Galaxy Redshift Survey (2dFGRS) for the redshift range 0.035 < z < 0.200 using the Wiener filtering method. The Wiener filter...
The 2dF Galaxy Redshift Survey: Wiener Reconstruction of the Cosmic Web (2003)
Erdogdu, Pirin, Lahav, Ofer, Zaroubi, Saleem, Efstathiou, George, Moody, Steve, Peacock, John A., ...
We reconstruct the underlying density field of the 2 degree Field Galaxy Redshift Survey (2dFGRS) for the redshift range 0.035
Isocurvature Fluctuations Induce Early Star Formation (2003)
Sugiyama, Naoshi, Zaroubi, Saleem, Silk, Joseph
The early reionisation of the Universe inferred from the WMAP polarisation results, if confirmed, poses a problem for the hypothesis that scale-invariant adiabatic density fluctuations account for...
Schaefer, Bjoern Malte, Pfrommer, Christoph, Zaroubi, Saleem
A method for estimating redshifts of galaxy clusters based solely on resolved Sunyaev-Zel'dovich (SZ) images is proposed. Given a high resolution SZ cluster image (with FWHM of approx. 1 arcmin), the...
Consistent beta values from density-density and velocity-velocity comparisons (2002)
Zaroubi, Saleem, Branchini, Enzo, Hoffman, Yehuda, Da Costa, Luiz N.
We apply a new algorithm, called the Unbiased Minimal Variance (hereafter UMV) estimator, to reconstruct the cosmic density and peculiar velocity fields in our local universe from the SEcat catalog...
Cosmic Flows: Review of Recent Developments (2002)
I review the recent developments in the analysis of cosmic flow data, in particular, latest results of bulk flow measurements, comparison between redshift and peculiar velocity catalogs with emphasis...
Constraints on reionization from the thermal history of the intergalactic medium (2002)
Theuns, Tom, Schaye, Joop, Zaroubi, Saleem, Kim, Tae-Sun, Tzanavaris, Panayiotis, Carswell, Bob
The temperature of the diffuse, photo-heated intergalactic medium (IGM) depends on its reionization history because the thermal time scales are long. The widths of the hydrogen Lyman-alpha absorption...
Temperature fluctuations in the intergalactic medium (2001)
Theuns, Tom, Zaroubi, Saleem, Kim, Tae-Sun, Tzanavaris, Panayiotis, Carswell, Robert F.
The temperature of the low-density intergalactic medium is set by the balance between adiabatic cooling resulting from the expansion of the universe, and photo-heating by the UV-background. We have...
Theuns, Tom, Zaroubi, Saleem, Kim, Tae-Sun
The temperature of the low-density intergalactic medium is set by the balance between adiabatic cooling resulting from the expansion of the universe, and photo-heating by the UV-background. A sudden...
Unbiased Reconstruction of the Large Scale Structure (2000)
We present a new Unbiased Minimal Variance (UMV) estimator for the purpose of reconstructing the large--scale structure of the universe from noisy, sparse and incomplete data. Similar to the Wiener...
Bumpy Power Spectra and dT/T (2000)
Griffiths, Louise M., Silk, Joseph, Zaroubi, Saleem
With the recent publication of the measurements of the radiation angular power spectrum from the BOOMERanG Antarctic flight (de Bernardis et al. 2000), it has become apparent that the currently...
Reconstructing the ZOA from Galaxy Peculiar Velocities (2000)
Galaxy peculiar velocity data provide important dynamical clues to the structures obscured by the Zone of Avoidance (hereafter, ZOA) with resolution >~ 500km/s. This indirect probe complements the...
Goodness-of-Fit Analysis of Radial Velocities Surveys (2000)
Hoffman, Yehuda, Zaroubi, Saleem
Using eigenmode expansion of the Mark-3 and SFI surveys of cosmological radial velocities a goodness-of-fit analysis is applied on a mode-by-mode basis. This differential analysis complements...
A wavelet analysis of QSO spectra (2000)
The temperature of the intergalactic medium (IGM) is an important factor in determining the line-widths of the absorption lines in the Lyman-alpha forest. We present a method to characterise the...
Large-Scale Power Spectrum and Cosmological Parameters from SFI Peculiar Velocities (1999)
Freudling, Wolfram, Zehavi, Idit, Da Costa, Luiz N., Dekel, Avishai, Eldar, Amiram, Giovanelli, Riccardo, ...
We estimate the power spectrum of mass density fluctuations from peculiar velocities of galaxies by applying an improved maximum-likelihood technique to the new all-sky SFI catalog. Parametric models...
Wiener Reconstruction of Large-Scale Structure from Peculiar Velocities (1998)
Zaroubi, Saleem, Hoffman, Yehuda, Dekel, Avishai
We present an alternative, Bayesian method for large-scale reconstruction from observed peculiar velocity data. The method stresses a rigorous treatment of the random errors and it allows...
Secondary Infall: Theory {\it Versus} Simulations (1995)
Zaroubi, Saleem, Naim, Avi, Hoffman, Yehuda
The applicability of the highly idealized secondary infall model to `realistic' initial conditions is investigated. The collapse of proto-halos seeded by $3\sigma$ density perturbations to an...
The formalism of Wiener filtering is applied to reconstruct, in terms of spherical harmonics, the projected $4\pi$ galaxy distribution of a mock IRAS 1.2 Jy catalog with a `Zone of Avoidance' $|b| =...
Fisher, Karl, Lahav, Ofer, Hoffman, Yehuda, Lynden-Bell, Donald, Zaroubi, Saleem
We present a new method for recovering the cosmological density, velocity, and potential fields from all-sky redshift catalogues. The method is based on an expansion of the fields in orthogonal...
Wiener Filtering of the COBE DMR Data (1994)
Bunn, Emory F., Fisher, Karl B., Hoffman, Yehuda, Lahav, Ofer, Silk, Joseph, Zaroubi, Saleem
We derive an optimal linear filter to suppress the noise from the COBE DMR sky maps for a given power spectrum. We then apply the filter to the first-year DMR data, after removing pixels within...
Clustering in Redshift Space: Linear Theory (1993)
Zaroubi, Saleem, Hoffman, Yehuda
The clustering in redshift space is studied here to first order within the framework of gravitational instability. The distortion introduced by the peculiar velocities of galaxies results in...