相关论文: Detecting sub-mJy sources with the EVN

Our previous work identified a class of SDSS quasars exhibiting multiple Gaia detections, classifying them as candidates for various astrophysical systems such as quasar-star pairs, dual quasars, and gravitationally lensed quasars. In this…

The Caltech-Jodrell Bank VLBI surveys of bright extragalactic radio sources north of declination 35 deg were carried out between 1990 and 1995 using the Mark-II system, achieving images with a resolution of about 1 mas at 5 GHz. The CJ1…

We present VLBI observations, carried out with the European Very Long Baseline Interferometry Network (EVN), of SDSSJ143244.91+301435.3, a radio-loud narrow-line Seyfert 1 (RLNLS1) characterized by a steep radio spectrum. The source,…

We investigate the nature of the compact, and possibly variable nuclear radio source in the centre of WISE J0716-19, the proposed host galaxy of fast radio burst, FRB 150418. We observed WISE J0716-19 at 5.0 GHz with the European VLBI…

We have used the Very Long Baseline Array (VLBA) to image five radio-quiet quasars (RQQs) at milliarcsecond resolution, at frequencies between 1.4 and 5 GHz. These quasars have typical total flux densities of a few millijansky at gigahertz…

Active galactic nuclei are the most luminous persistent (non-transient, even if often variable) objects in the Universe. They are bright in the entire electromagnetic spectrum. Blazars are a special class where the jets point nearly to our…

We present the results of deep, high-resolution, 5 GHz Expanded Very Large Array (EVLA) observations of the nearby, dwarf lenticular galaxy and intermediate mass black hole candidate (M ~4.5 x 10^5 M_sun), NGC 404. For the first time, radio…

Very-high-energy $\gamma$-ray observations of the active galaxy IC 310 with the MAGIC telescopes have revealed fast variability with doubling time scales of less than 4.8min. This implies that the emission region in IC 310 is smaller than…

The capabilities of the Global mm-VLBI Array are summarized and demonstrated through actual images from our monitoring of extragalactic radio jets. This sensitive 3mm-VLBI interferometer is able to provide images of up to 50 microarcseconds…

There are approximately 250 quasars discovered at redshift $z\geq6$, of which only a handful were detected in radio bands, and even fewer were imaged with the highest resolution very long baseline interferometry (VLBI) technique. Here we…

As part of an on-going study of radio transients in Epoch 1 (2017-2019) of the Very Large Array Sky Survey (VLASS), we have discovered a sample of 0.2<z<3.2 active galactic nuclei (AGN) selected in the optical/infrared that have recently…

The East Asian VLBI Network (EAVN) is an international VLBI facility in East Asia and is operated under mutual collaboration between East Asian countries, as well as part of Southeast Asian and European countries. EAVN currently consists of…

We present a census of sub-pc scale properties of the VLBI cores in a complete sample of local Seyfert galaxies. Seventeen out of 23 sources with a VLA detection are detected also with VLBI at 1.7 GHz and/or 5 GHz, with an average…

The nearby (d=3.6 Mpc) starburst galaxy M82 has been studied for several decades by very long baseline interferometry (VLBI) networks such as e-MERLIN and the European VLBI Network (EVN). The numerous supernova remnants (SNRs), HII regions…

Observations of gamma-ray bursts (GRBs) at Very High Energy (VHE) offer a unique opportunity to investigate particle acceleration processes, magnetic fields and radiation fields in these events. Very Long Baseline Interferometry (VLBI)…

A subset of ultraluminous X-ray sources (those with luminosities < 10^40 erg/s) are thought to be powered by the accretion of gas onto black holes with masses of ~5-20 M_solar, probably via an accretion disc. The X-ray and radio emission…

We conducted millimeter continuum observations for samples of nearby early-type galaxies (21 sources) and nearby low-luminosity active galactic nuclei (LLAGN; 16 sources) at 100 GHz (3 mm) using the Nobeyama Millimeter Array (NMA). In…

In order to find more examples of the elusive high-redshift molecular absorbers, we have embarked on a systematic discovery program for highly obscured, radio-loud "invisible AGN" using the VLA Faint Images of the Radio Sky at Twenty…

Star forming galaxies are thought to dominate the sub-mJy radio population, but recent work has shown that low luminosity AGN can still make a significant contribution to the faint radio source population. Spectral indices are an important…

Intermediate mass black holes (10^2 < M_BH< 10^5 Msun) are an open question in our understanding of black hole evolution and growth. They have long been linked to dense star cluster environments thanks to cluster dynamics, but there are a…