126 citations · 1k across the 43 of their papers we have counts for
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MALS discovery of a rare HI 21-cm absorber at : origin of the absorbing gas in powerful AGN
P. P. Deka, N. Gupta, H. W. Chen +14
We report a new, rare detection of HI 21-cm absorption associated with a quasar (only six known at ) here towards J2339-5523 at = 1.3531, discovered through the Mee…
Proximate molecular quasar absorbers: Chemical enrichment and kinematics of the neutral gas
P. Noterdaeme, S. Balashev, R. Cuellar +7
Proximate molecular quasar absorbers (PH2) are an intriguing population of absorption systems recently uncovered through strong H2 absorption at small velocity separation from the…
Discovery of Hydrogen Radio Recombination Lines at z=0.89 towards PKS 1830-211
Kimberly L. Emig, Neeraj Gupta, Pedro Salas +14
We report the detection of stimulated hydrogen radio recombination line (RRL) emission from ionized gas in a galaxy using 580--1670 MHz observations from the MeerKAT Absor…
PKS1413+135: OH and HI at z = 0.247 with MeerKAT
F. Combes, N. Gupta, S. Muller +13
The BL Lac PKS 1413+135 was observed by the Large Survey Project "MeerKAT Absorption Line Survey" (MALS) in the L-band, at 1139 MHz and 1293-1379 MHz, targeting the HI and OH lines…
Mapping HI 21-cm in the Klemola 31 group at z = 0.029: emission and absorption towards PKS2020-370
E. K. Maina, Abhisek Mohapatra, G. I. G. Jozsa +11
We present MeerKAT Absorption Line Survey (MALS) observations of the HI gas in the Klemola31 galaxy group (), located along the line of sight to the radio-loud quasar PKS2…
Emergence of a new HI 21-cm absorption component at z~1.1726 towards the gamma-ray blazar PKS~2355-106
Raghunathan Srianand, Neeraj Gupta, Patrick Petitjean +12
We report the emergence of a new HI 21-cm absorption at z_abs = 1.172635 in the damped Lyman-alpha absorber (DLA) towards the gamma-ray blazar PKS 2355-106 (z_em~1.639) using scien…
HI gas playing hide-and-seek around a powerful FRI-type quasar at z2.1
N. Gupta, R. Srianand, E. Momjian +5
We present optical spectroscopic and milli-arcsecond scale radio continuum observations of the quasar M1540-1453 ( = 2.1040.002) that shows associated HI 21-cm absorpt…
Discovery of a damped Ly absorber originating in a spectacular interacting dwarf galaxy pair at
Erin Boettcher, Neeraj Gupta, Hsiao-Wen Chen +18
We present the discovery of neutral gas detected in both damped Ly absorption (DLA) and HI 21-cm emission outside of the stellar body of a galaxy, the first such detection in th…
Multi-phase gas properties of extremely strong intervening DLAs towards quasars
A. Ranjan, R. Srianand, P. Petitjean +6
We present the results of a spectroscopic analysis of extremely strong damped Lyman-α absorbers (ESDLAs, log N(Hi)>=21.7) observed with VLT-XShooter. ESDLAs probe gas from within t…
Damped Ly-alpha Absorbers in Star-forming Galaxies at z < 0.15 Detected with the Hubble Space Telescope and Implications for Galaxy Evolution
Varsha P. Kulkarni, David V. Bowen, Lorrie A. Straka +4
We report {\it HST} COS spectroscopy of 10 quasars with foreground star-forming galaxies at 0.02 0.14 within impact parameters of 1-7 kpc. We detect damped/sub-dampe…
Spatially resolved Lyman- emission around radio bright quasars
Gitika Shukla, Raghunathan Srianand, Neeraj Gupta +4
We use Southern African Large Telescope (SALT) to perform long-slit spectroscopic observations of 23 newly discovered radio-loud quasars (RLQs) at . The sample consists…
MALS SALT-NOT survey of MIR-selected powerful radio-bright AGN at 0<z<3.5
N. Gupta, G. Shukla, R. Srianand +20
We present results of an optical spectroscopic survey using SALT and NOT to build a WISE mid-infrared color-based, dust-unbiased sample of powerful radio-bright (200 mJy at 1.4…
Lyman- emission from a WISE-selected optically faint powerful radio galaxy M151304.72-252439.7 at = 3.132
Gitika Shukla, Raghunathan Srianand, Neeraj Gupta +4
We report the detection of a large ( kpc) and luminous nebula [ = ] around an optically f…
OH in the diffuse interstellar medium: physical modelling and prospects with upcoming SKA precursor/pathfinder surveys
Sergei Balashev, Neeraj Gupta, Daria Kosenko
Hydroxyl () is known to form efficiently in cold gas (K) along with the molecule and can be used as an efficient tracer of the diffuse molecular gas in…
uGMRT HI 21-cm absorption observations of two extremely inverted spectrum sources
Mukul Mhaskey, Surajit Paul, Neeraj Gupta +2
We report the detection of HI 21-cm absorption in a member of the rare and recently discovered class of compact radio sources, 'Extremely Inverted Spectrum Extragalactic Radio Sour…
uGMRT search for cold gas at z~1-1.4 towards red quasars
Rajeshwari Dutta, Raghunathan Srianand, Neeraj Gupta +1
We present results from our search for HI 21-cm and OH 18-cm absorption at z~1-1.4 towards red quasars showing strong MgII absorption using uGMRT. The quasars J1501+1822 and J1521+…
Prevalence of neutral gas in centres of merging galaxies
Rajeshwari Dutta, Raghunathan Srianand, Neeraj Gupta
We present Giant Metrewave Radio Telescope and Very Large Array observations of HI 21-cm absorption in ten z<=0.2 galaxy mergers that host strong radio sources. Seven of these merg…
Molecular gas and star formation in an absorption-selected galaxy: Hitting the bull's eye at z = 2.46
A. Ranjan, P. Noterdaeme, J. -K. Krogager +8
We present the detection analysis of a diffuse molecular cloud at z=2.4636 towards the quasar SDSS J1513+0352(z 2.68) observed with the X-shooter spectrograp…
Incidence of HI 21-cm absorption in strong FeII systems at
R. Dutta, R. Srianand, N. Gupta +5
We present the results from our search for HI 21-cm absorption in a sample of 16 strong FeII systems ((MgII ) Å and (FeII )…
Mapping kiloparsec-scale structures in the extended HI disc of the galaxy UGC 00439 by HI 21-cm absorption
Rajeshwari Dutta, Neeraj Gupta, Raghunathan Srianand +1
We study the properties of HI gas in the outer regions (~2r_25) of a spiral galaxy, UGC 00439 (z = 0.01769), using HI 21-cm absorption towards different components of an extended b…
A giant radio halo in a low-mass SZ-selected galaxy cluster: ACT-CL J0256.5+0006
Kenda Knowles, Huib T. Intema, Andrew J. Baker +18
We present the detection of a giant radio halo (GRH) in the Sunyaev-Zel'dovich (SZ)-selected merging galaxy cluster ACT-CL J0256.5+0006 (), observed with the Giant Metre…
Associated H{\sc i} absorption towards the core of the radio galaxy 3C 321
Yogesh Chandola, S. K. Sirothia, D. J. Saikia +1
We report the results of Giant Metrewave Radio Telescope (GMRT) observations of H{\sc i} absorption towards the FRII radio galaxy 3C321 (J1531+2404), which is associated with an ac…