126 citations · 1k across the 43 of their papers we have counts for
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The MeerKAT Absorption Line Survey: Homogeneous continuum catalogues towards a measurement of the cosmic radio dipole
J. D. Wagenveld, H. -R. Klöckner, N. Gupta +21
The number counts of homogeneous samples of radio sources are a tried and true method of probing the large scale structure of the Universe, as most radio sources outside the galact…
A GMRT Narrowband vs. Wideband Analysis of the ACT-CLJ0034.4+0225 Field Selected from the ACTPol Cluster Sample
Sinenhlanhla P. Sikhosana, Kenda Knowles, C. H. Ishwara-Chandra +3
Low frequency radio observations of galaxy clusters are a useful probe of the non-thermal intracluster medium (ICM), through observations of diffuse radio emission such as radio ha…
GMRT 610 MHz observations of galaxy clusters in the ACT equatorial sample
Kenda Knowles, Andrew J. Baker, J. Richard Bond +11
We present Giant Metrewave Radio Telescope 610 MHz observations of 14 Atacama Cosmology Telescope (ACT) clusters, including new data for nine. The sample includes 73\% of ACT equat…
The Radio Relics and Halo of El Gordo, a Massive Cluster Merger
Robert R. Lindner, Andrew J. Baker, John P. Hughes +8
We present 610 MHz and 2.1 GHz imaging of the massive SZE-selected z=0.870 cluster merger ACT-CL J0102-4915 (El Gordo), obtained with the GMRT and the ATCA, respectively. We detect…
Associated 21-cm absorption towards the cores of radio galaxies
Yogesh Chandola, Neeraj Gupta, D. J. Saikia
We present the results of Giant Metrewave Radio Telescope (GMRT) observations to detect H{\sc i} in absorption towards the cores of a sample of radio galaxies. From observations of…
Parsec-scale structures and diffuse bands in a translucent interstellar medium at z 0.079
R. Srianand, N. Gupta, H. Rahmani +3
We present a detailed study of the QSO-galaxy pair [SDSS J163956.35+112758.7 (zq = 0.993) and SDSS J163956.38+112802.1 (zg = 0.079)] based on observations carried out using the Gia…
Constraining the variation of fundamental constants at z ~ 1.3 using 21-cm absorbers
H. Rahmani, R. Srianand, N. Gupta +3
We present high resolution optical spectra obtained with the Ultraviolet and Visual Echelle Spectrograph (UVES) at the Very Large Telescope (VLT) and 21-cm absorption spectra obtai…
Search for cold gas in z>2 damped Lyman-alpha systems: 21-cm and H_2 absorption
R. Srianand, N. Gupta, P. Petitjean +4
(Abridged) We present the results of a systematic GBT and GMRT survey for 21-cm absorption in a sample of 10 DLAs at 2<z_abs<3.4. Analysis of L-band VLBA images of the background Q…
GMRT mini-survey to search for 21-cm absorption in Quasar-Galaxy Pairs at z~0.1
N. Gupta, R. Srianand, D. V. Bowen +2
We present the results from our 21-cm absorption survey of a sample of 5 quasar-galaxy pairs (QGPs), with the redshift of the galaxies in the range 0.03<zg<0.18, selected from the…
Constraining fundamental constants of physics with quasar absorption line systems
Patrick Petitjean, Raghunathan Srianand, Hum Chand +3
We summarize the attempts by our group and others to derive constraints on variations of fundamental constants over cosmic time using quasar absorption lines. Most upper limits res…
A complete sample of 21-cm absorbers at z~1.3: Giant Metrewave Radio Telescope Survey Using MgII Systems
N. Gupta, R. Srianand, P. Petitjean +2
We present the results of a systematic Giant Metrewave Radio Telescope (GMRT) survey of 21-cm absorption in a representative and unbiased sample of 35 strong MgII systems in the re…