相关论文: NGC 4869 in the Coma cluster: twist, wrap, overlap…

We present high-sensitivity follow-up observations of the giant fossil radio lobe in the Ophiuchus galaxy cluster with the upgraded Giant Metrewave Radio Telescope (uGMRT) in the 125-250 MHz and 300-500 MHz frequency bands. The new data…

We present the results of observations performed with the Sardinia Radio Telescope (SRT) at 1.3-1.8 GHz of the galaxy cluster CL 0217+70 and a $3^\circ \times 3^\circ$ region around it. We combine the SRT data with archival Very Large Array…

We report moderate resolution 3-5 micron spectroscopy of the nucleus of NGC 1068 obtained at 0.3 arcsec (20 pc) resolution with the spectrograph slit aligned approximately along the ionization cones of the AGN. The deconvolved FWHM of the…

(Abridged) We describe the results of the highest-resolution radio observations yet made of four relic radio sources in the Abell clusters A13, A85, A133 and A4038. Our VLA images at 1.4 GHz with 4" resolution show a remarkable variety of…

Abell 1351 is a massive merging cluster that hosts a giant radio halo and a bright radio edge blended in the halo. In this paper, we present the first ever spectral analysis of this cluster using GMRT 610 MHz and VLA 1.4 GHz archival data…

Some merging galaxy clusters host diffuse extended radio emission, so-called radio halos and relics. Here we present observations between 147 MHz and 4.9 GHz of a new radio-selected galaxy cluster 1RXS J0603.3+4214 (z=0.225). The cluster is…

We report a serendipitous discovery of a pair of relic lobes separated by 1.86 Mpc and straddling the radio-loud quasar 4C 34.47. The axis connecting them makes an appreciable angle with the axis of its well-known double-lobed radio…

We investigate the X-ray properties of the powerful radio galaxy Hercules A (3C 348) using ROSAT HRI, PSPC and ASCA observations. The ASCA data are well fit by a thermal plasma model with a temperature of about 4.3 keV and abundances 0.4…

We present polarization images from the Karl G. Jansky Very Large Array (VLA) and the Giant {Metrewave} Radio Telescope (GMRT) at 5.5, 10 GHz and 663 MHz of the changing-look (CL) AGN, NGC3516. A transverse gradient in the rotation measure…

We present the results of deep radio observations of 7 nearby large galaxies observed using the upgraded Giant Metrewave Radio Telescope (uGMRT) 0.3-0.5 GHz receivers with an angular resolution of $\sim$10 arcsec. The achieved sensitivities…

A strong effort has been devoted to understand the physical origin of radio emission from low-luminosity AGN (LLAGN), but a comprehensive picture is still missing. We used high-resolution ($\le$1 arcsec), multi-frequency (1.5, 5.5, 9 and 14…

Relativistic jets originating at the center of AGN are embedded in extreme environments with strong magnetic fields and high particle densities, which makes them a fundamental tool for studying the physics of magnetized plasmas. We aim to…

We present new imaging observations of the remnant of Supernova (SN) 1987A at 44 GHz, performed in 2011 with the Australia Telescope Compact Array (ATCA). The $0\farcs35\times0\farcs23$ resolution of the diffraction-limited image is the…

We present deep total intensity and polarization observations of the Coma cluster at 1.4 and 6.6 GHz performed with the Sardinia Radio Telescope. By combining the single-dish 1.4 GHz data with archival Very Large Array observations we…

The Seyfert galaxy NGC 4151 has been imaged at resolution better than 0.1 pc using a VLBI array consisting of the VLBA and three 100m-class telescopes. A flat-spectrum 3-mJy source with a monochromatic radio power of ~10^{37} ergs/s has…

We observed the cluster CIZA J2242.8+5301 with the Arcminute Microkelvin Imager at $16$ GHz and present the first high radio-frequency detection of diffuse, non-thermal cluster emission. This cluster hosts a variety of bright, extended,…

The head--tail (HT) morphology of radio galaxies is seen for a class of radio sources where the primary lobes are being bent in the intercluster weather due to strong interactions between the radio jets and their respective intracluster…

The low-luminosity active galactic nuclei in NGC 3147, NGC 4203, and NGC 4579 have been imaged at four frequencies with the Very Long Baseline Array. The galaxies are unresolved at all frequencies, with size upper limits of $10^3-10^4$…

We study the stellar population far into the halo of one of the two brightest galaxies in the Coma cluster, NGC 4889, based on deep medium resolution spectroscopy with FOCAS at the Subaru 8.2m telescope. We fit single stellar population…

We report on the discovery of four new radio galaxies with tailed morphology. Tailed radio galaxies are generally found in rich environments, therefore their presence can be used as tracer of a cluster. The radio galaxies were found in the…