39 citations · 199 across the 13 of their papers we have counts for
13 papers
Intensity fluctuations of radio halo in galaxy cluster: Insights from power spectrum estimation
Srijita Pal, Nirupam Roy, Sameer Salunkhe +3
Non-thermal synchrotron emissions from radio halo allow us to study mechanisms of particle (re)acceleration, magnetic field distribution, merger history, and turbulence in the intr…
Detection of non-thermal radio emission components from the Orion Nebula: stellar jets, cloud collision or feedback from stellar winds?
Md Rashid, Nirupam Roy, Prasun Dutta +5
The Orion Nebula is the closest high-mass star-forming region, making it an ideal laboratory to investigate physical processes in complex star-forming environments. At radio freque…
ELAIS-N1 deep field uGMRT Band-2: constraints on diffuse Galactic synchrotron emission power spectrum
Rashmi Sagar, Abhirup Datta, Arnab Chakraborty +13
We present high sensitivity, low radio frequency continuum observations of the ELAIS-N1 field with 32 hours of observations of the uGMRT Band-2 ( MHz) covering $5.86\,\tex…
Towards -cm intensity mapping at with uGMRT using the tapered gridded estimator -- IV. Wideband analysis
Khandakar Md Asif Elahi, Somnath Bharadwaj, Srijita Pal +8
We present a Wideband Tapered Gridded Estimator (TGE), which incorporates baseline migration and variation of the primary beam pattern for neutral hydrogen (${\rm H\hspace{0.5mm}}{…
Towards -cm intensity mapping at with uGMRT using the tapered gridded estimator III: Foreground removal
Khandakar Md Asif Elahi, Somnath Bharadwaj, Srijita Pal +8
Neutral hydrogen (HI) -cm intensity mapping (IM) is a promising probe of the large-scale structures in the Universe. However, a few orders of magnitude brighter foregrounds obs…
Towards -cm intensity mapping at with uGMRT using the tapered gridded estimator II: Cross-polarization power spectrum
Kh. Md. Asif Elahi, Somnath Bharadwaj, Abhik Ghosh +8
Neutral hydrogen () -cm intensity mapping (IM) offers an efficient technique for mapping the large-scale structures in the universe. We introduce the 'Cross' Tapered G…
Probing early universe through redshifted 21-cm signal: Modelling and observational challenges
Abinash Kumar Shaw, Arnab Chakraborty, Mohd Kamran +8
The redshifted 21-cm radiation from the atomic hydrogen (HI) provides an excellent direct probe to study the evolution of HI in IGM and thus reveal the nature of the first luminous…
Towards 21-cm Intensity Mapping at with uGMRT using the Tapered Gridded Estimator I: Foreground Avoidance
Srijita Pal, Kh. Md. Asif Elahi, Somnath Bharadwaj +8
The post-reionization neutral hydrogen (HI) 21-cm intensity mapping signal holds the potential to probe the large scale structures, study the expansion history and cons…
Demonstrating the Tapered Gridded Estimator (TGE) for the Cosmological HI 21-cm Power Spectrum using GMRT observations
Srijita Pal, Somnath Bharadwaj, Abhik Ghosh +1
We apply the Tapered Gridded Estimator (TGE) for estimating the cosmological 21-cm power spectrum from GMRT observations which corresponds to the neutral hydroge…
First multi-redshift limits on post-Epoch of Reionization (post-EoR) 21 cm signal from z = 1.96 - 3.58 using uGMRT
Arnab Chakraborty, Abhirup Datta, Nirupam Roy +8
Measurement of fluctuations in diffuse HI 21 cm background radiation from the post-reionization epoch (z < 6) is a promising avenue to probe the large-scale structure of the Univer…
Detailed study of ELAIS N1 field with the uGMRT -- II. Source Properties and Spectral Variation Of Foreground Power Spectrum from 300-500 MHz Observations
Arnab Chakraborty, Nirupam Roy, Abhirup Datta +8
Understanding the low-frequency radio sky in depth is necessary to subtract foregrounds in order to detect the redshifted 21 cm signal of neutral hydrogen from the Cosmic Dawn, Epo…
Detailed study of the ELAIS N1 field with the uGMRT - I. Characterizing the 325 MHz foreground for redshifted 21 cm observations
Arnab Chakraborty, Abhirup Datta, Samir Choudhuri +8
In this first paper of the series, we present initial results of newly upgraded Giant Meterwave Radio Telescope (uGMRT) observation of European Large-Area ISO Survey-North 1 (ELAIS…
A Tapered Gridded Estimator (TGE) for the Multi-Frequency Angular Power Spectrum (MAPS) and the Cosmological HI 21-cm Power Spectrum
Somnath Bharadwaj, Srijita Pal, Samir Choudhuri +1
In this work we present a new approach to estimate the power spectrum of redshifted HI 21-cm brightness temperature fluctuations. The MAPS complete…