188 citations · 741 across the 24 of their papers we have counts for
24 papers
Impact of Large-Scale Anisotropies on Galaxy Clustering and Cosmological Constraints
Prabhakar Tiwari
We critically assess the impact of significant dipole and large-scale anisotropies on galaxy clustering signals, with a focus on radio continuum surveys. Our study reveals that the…
An Independent Measure of the Kinematic Dipole from SDSS
Prabhakar Tiwari, Dominik J. Schwarz, Gong-Bo Zhao +3
We utilize the Sloan Digital Sky Survey (SDSS) extended Baryon Oscillation Spectroscopic Survey (eBOSS) and Baryon Oscillation Spectroscopic Survey (BOSS) catalogs with precise spe…
Probing Cosmology beyond CDM using the SKA
Shamik Ghosh, Pankaj Jain, Rahul Kothari +3
The cosmological principle states that the Universe is statistically homogeneous and isotropic at large distance scales. There currently exist many observations which indicate a de…
A study of Dipolar Signal in distant Quasars with various observables
Rahul Kothari, Mohit Panwar, Gurmeet Singh +2
We study the signal of anisotropy in AGNs/quasars of CatWISE2020 catalogue using different observables. It has been reported earlier that this data shows a strong signal of dipole…
The clustering properties of AGNs/quasars in CatWISE2020 catalog
Prabhakar Tiwari, Gong-Bo Zhao, Adi Nusser
We study the clustering properties of 1,307,530 AGNs/quasars in the CatWISE2020 catalog prepared using the Wide-field Infrared Survey Explorer (WISE) and Near-Earth Object Wide-fie…
Superhorizon perturbations: A possible explanation of the Hubble--Lemaître Tension and the Large Scale Anisotropy of the Universe
Prabhakar Tiwari, Rahul Kothari, Pankaj Jain
Current cosmological observations point to a serious discrepancy between the observed Hubble parameter obtained using direct and cosmic microwave background radiation (CMBR) measur…
A mechanism to explain Galaxy alignment over a range of scales
Prabhakar Tiwari, Pankaj Jain
The observed large-scale alignment of polarization angles and galaxy axis have been challenging the fundamental assumption of homogeneity and isotropy in standard cosmology since m…
Galaxy power spectrum and biasing results from the LOFAR Two-metre Sky Survey (first data release)
Prabhakar Tiwari, Ruiyang Zhao, Jinglan Zheng +3
The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing survey aiming to observe the entire Northern sky, providing an excellent opportunity to study the distribution and evolution of…
The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the emission line galaxy sample from the anisotropic power spectrum between redshift 0.6 and 1.1
Arnaud de Mattia, Vanina Ruhlmann-Kleider, Anand Raichoor +33
We analyse the large-scale clustering in Fourier space of emission line galaxies (ELG) from the Data Release 16 of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spect…
The galaxy power spectrum from TGSS ADR1 and the effect of flux calibration systematics
Prabhakar Tiwari, Shamik Ghosh, Pankaj Jain
We explore the large to moderate scale anisotropy in distant radio sources using the TGSS ADR1 catalog. We use different measures, i.e. number counts, sky brightness and flux per s…
Weak Lensing Effect on CMB in the Presence of a Dipole Anisotropy
Abhineet Agarwal, Naveen K. Singh, Pankaj Jain +1
We investigate weak lensing effect on cosmic microwave background (CMB) in the presence of dipole anisotropy. The approach of flat-sky approximation is considered. We determine the…
Large angular scale multipoles at redshift ~0.8
Prabhakar Tiwari, Pavan K. Aluri
We prepare the full sky radio galaxy map () using the north NVSS and south SUMSS galaxy catalogs and study the large scale multipoles anomalies. These galaxies are…
Evidence of isotropy at large-scale from polarizations of radio sources
Prabhakar Tiwari, Pankaj Jain
We test the isotropy of radio polarization angle orientations with a robust and reliable dual frequency polarimetric survey of active galactic nuclei (AGN). We find that the polari…
Probing statistical isotropy of cosmological radio sources using SKA
Shamik Ghosh, Pankaj Jain, Gopal Kashyap +3
There currently exist many observations which are not consistent with the cosmological principle. We review these observations with a particular emphasis on those relevant for Squa…
Constraining axionlike particles using the distance-duality relation
Prabhakar Tiwari
One of the fundamental results used in observational cosmology is the distance duality relation (DDR), which relates the luminosity distance, , with angular diameter distance,…
Radio spectral index from NVSS and TGSS
Prabhakar Tiwari
I extract the radio spectral index, , from 541,195 common sources observed in the 150 MHz TIFR GMRT Sky Survey (TGSS) and the 1.4 GHz NRAO VLA Sky Survey (NVSS). This large comm…
Revisiting the NVSS number count dipole
Prabhakar Tiwari, Adi Nusser
We present a realistic modeling of the dipole component of the projected sky distribution of NVSS radio galaxies. The modeling relies on mock catalogs generated within the context…
The clustering of radio galaxies: biasing and evolution versus stellar mass
Adi Nusser, Prabhakar Tiwari
We study the angular clustering of NVSS sources on scales Mpc in the context of the CDM scenario. The analysis partially relies on the re…
Extracting Spectral Index of Intergalactic Magnetic Field from Radio Polarizations
Prabhakar Tiwari, Pankaj Jain
We explain the large scale correlations in radio polarization in terms of the correlations of galaxy cluster/supercluster magnetic field. Assuming that the polarization correlation…
Dipole Anisotropy in Integrated Linearly Polarized Flux Density in NVSS Data
Prabhakar Tiwari, Pankaj Jain
We study the dipole anisotropy in integrated linearly polarization flux density in NRAO VLA Sky Survey (NVSS). We extract the anisotropy parameters in the number counts, number cou…
Dipole anisotropy in sky brightness and source count distribution in radio NVSS data
Prabhakar Tiwari, Rahul Kothari, Abhishek Naskar +2
We study the dipole anisotropy in number counts and flux density weighted number counts {or sky brightness} in the NRAO VLA Sky Survey (NVSS) data. The dipole anisotropy is expecte…
New limit on pseudoscalar-photon mixing from WMAP Observations
Prabhakar Tiwari
The pseudoscalar-photon mixing in presence of large scale magnetic field induces polarization in light from distant cosmological sources. We study the effect of these pseudoscalars…
Polarization Alignment in JVAS/CLASS flat spectrum radio surveys
Prabhakar Tiwari, Pankaj Jain
We present a detailed statistical analysis of the alignment of polarizations of radio sources at high redshift. We use the JVAS/CLASS 8.4-GHz surveys for our study. This study is m…
A complete 3D numerical study of the effects of pseudoscalar-photon mixing on quasar polarizations
Nishant Agarwal, Pavan K. Aluri, Pankaj Jain +2
We present the results of three-dimensional simulations of quasar polarizations in the presence of pseudoscalar-photon mixing in the intergalactic medium. The intergalactic magneti…