430 citations · 3.1k across the 94 of their papers we have counts for
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325-MHz observations of the ELAIS-N1 field using the Giant Metrewave Radio Telescope
S. K. Sirothia, M . Dennefeld, D. J. Saikia +3
We present observations of the European Large-Area {\it ISO} Survey-North 1 (ELAIS-N1) at 325 MHz using the Giant Metrewave Radio Telescope (GMRT), with the ultimate objective of i…
Deep low-frequency observations with the Giant Metrewave Radio Telescope: a search for relic radio emission
S. K. Sirothia, D. J. Saikia, C. H. Ishwara-Chandra +1
We present deep multifrequency observations using the Giant Metrewave Radio Telescope at 153, 244, 610 and 1260 MHz of a field centered on J0916+6348, to search for evidence of fos…
Detection of the 2175Å~ extinction feature and 21-cm absorption in two MgII systems at z~1.3
R. Srianand, N. Gupta, P. Petitjean +2
We have discovered two dusty intervening MgII absorption systems at z~1.3 in the Sloan Digital Sky Survey (SDSS) database. The overall spectra of both QSOs are red (u-K>4.5 mag) an…
J1420--0545: The radio galaxy larger than 3C236
J. Machalski, D. Kozieł-Wierzbowska, M. Jamrozy +1
We report the discovery of the largest giant radio galaxy, J1420-0545: a FR type II radio source with an angular size of 17.4' identified with an optical galaxy at z=0.3067. Thus,…
A multifrequency study of giant radio sources I. Low-frequency Giant Metrewave Radio Telescope observations of selected sources
C. Konar, M. Jamrozy, D. J. Saikia +1
We present low-frequency observations with the Giant Metrewave Radio Telescope (GMRT) of a sample of giant radio sources (GRSs), and high-frequency observations of three of these s…
Radio morphology and spectral analysis of cD galaxies in rich and poor galaxy clusters
S. Giacintucci, T. Venturi, M. Murgia +5
We present a radio morphological study and spectral analysis for a sample of 13 cD galaxies in rich and poor clusters of galaxies.} Our study is based on new high sensitivity Giant…
NGC4438 and its environment at radio wavelengths
Ananda Hota, D. J. Saikia, Judith A. Irwin
We present multi-frequency, radio-continuum and HI observations of NGC4438, the highly-disturbed, active galaxy in the Virgo cluster, with the VLA and the GMRT. High-resolution obs…
Intermittent jet activity in the radio galaxy 4C29.30?
M. Jamrozy, C. Konar, D. J. Saikia +3
We present radio observations at frequencies ranging from 240 to 8460 MHz of the radio galaxy 4C29.30 (J0840+2949) using the Giant Metrewave Radio Telescope (GMRT), the Very Large…
High sensitivity low frequency radio observations of cD galaxies
S. Giacintucci, T. Venturi, S. Bardelli +3
We present the GMRT 235 MHz images of three radio galaxies and 610 MHz images of two sources belonging to a complete sample of cD galaxies in rich and poor galaxy clusters. The ana…
Detecting cold gas at intermediate redshifts: GMRT survey using Mg II systems
Neeraj Gupta, R. Srianand, P. Petitjean +3
Intervening HI 21-cm absorption systems at z > 1.0 are very rare and only 4 confirmed detections have been reported in the literature. Despite their scarcity, they provide interest…
3C254: MERLIN observations of a highly asymmetric quasar
P. Thomasson, D. J. Saikia, T. W. B. Muxlow
Multifrequency, high-resolution radio observations of the quasar 3C254 using MERLIN are presented. The quasar has a highly asymmetric radio structure, with the eastern component of…
Associated 21-cm HI absorption towards the radio galaxy 3C452 (J2245+3941)
Neeraj Gupta, D. J. Saikia
We report the detection of 21-cm HI absorption towards the core of the Fanaroff-Riley II radio galaxy 3C452 (J2245+3941). The absorption profile is well resolved into three compone…
Unification scheme and the distribution of neutral gas in compact radio sources
Neeraj Gupta, D. J. Saikia
We examine the consistency of HI properties with the unification scheme for radio galaxies and quasars, and any correlation with the symmetry parameters for a sample of CSS and GPS…
J0041+3224: a new double-double radio galaxy
D. J. Saikia, C. Konar, V. K. Kulkarni
We report the discovery of a double-double radio galaxy (DDRG), J0041+3224, with the Giant Metrewave Radio Telescope (GMRT) and subsequent high-frequency observations with the Very…
Jet propagation and the asymmetries of CSS radio sources
S. Jeyakumar, Paul J. Wiita, D. J. Saikia +1
As Compact Steep Spectrum radio sources have been shown to be more asymmetrical than larger sources of similar powers, there is a high probability that they interact with an asymme…
Radio sources at low Galactic latitudes
D. J. Saikia, P. Thomasson, S. Roy +2
We present high-resolution radio observations of a sample of 65 radio sources at low Galactic latitudes. The sources were all observed at 5 GHz with the Very Large Array A-array. M…
HI in NGC 5433 and its Environment: High-Latitude Emission in a Small Galaxy Group
K. Spekkens, J. A. Irwin, D. J. Saikia
We present HI synthesis maps of the edge-on starburst NGC 5433 and its environment, obtained with the VLA in its C and D configurations. The observations and spectral model residua…
J1432+158: the most distant giant quasar
A. K. Singal, C. Konar, D. J. Saikia
We present low-frequency, GMRT (Giant Metrewave Radio Telescope) observations at 333 and 617 MHz of the most-distant giant quasar, J1432+158, which is at a redshift of 1.005. The r…
3C459: A highly asymmetric radio galaxy with a starburst
P. Thomasson, D. J. Saikia, T. W. B. Muxlow
Multifrequency radio observations of the radio galaxy 3C459 using MERLIN, VLA and the EVN, and an optical HST image using the F702W filter are presented. The galaxy has a very asym…
Symmetry Parameters of CSS Sources: Evidence of Fuelling?
D. J. Saikia, S. Jeyakumar, F. Mantovani +4
The compact steep spectrum (CSS) and gigahertz peaked spectrum (GPS) sources are widely believed to be young radiosources, with ages <10^6 yr. If the activity in the nucleus is fue…
Polarization asymmetry in CSS sources: evidence of AGN fuel?
D. J. Saikia, Neeraj Gupta
The compact steep spectrum and gigahertz peaked spectrum sources are widely believed to be young radio sources, with ages <10^6 yr. If the activity in the nucleus is fuelled by the…
High Latitude Dust and the 617 MHz - 850 μm relation in NGC 5775
Rupinder Singh Brar, Judith A. Irwin, D. J. Saikia
We present continuum observations of the edge-on spiral galaxy NGC 5775 at 617 MHz with the Giant Metrewave Radio Telescope (GMRT) and at 850 μm with the Submillimetre Common-User…
CSSs in a sample of B2 radio sources of intermediate strength
D. J. Saikia, P. Thomasson, R. E. Spencer +3
We present radio observations of 19 candidate compact steep-spectrum (CSS) objects selected from a well-defined, complete sample of 52 B2 radio sources of intermediate strength. Th…
B1524-136: A CSS quasar with two-sided radio jets
F. Mantovani, D. J. Saikia, M. Bondi +3
We present MERLIN, global VLBI and VLBA observations of the high-luminosity, compact steep-spectrum quasar B1524136 at cm wavelengths. These observations reveal well-defined rad…