English
Related papers

Related papers: Detecting sub-mJy sources with the EVN

200 papers

We have used the VLBA at 5 GHz to observe all galaxies with nuclear radio flux densities above 3.5 mJy found in a VLA survey at 15 GHz of a sample of nearby LINER galaxies. All galaxies were detected revealing high brightness temperature…

Astrophysics · Physics 2009-10-31 Heino Falcke , Neil M. Nagar , Andrew S. Wilson , James S. Ulvestad

The large majority of extragalactic very high energy (VHE; E>100 GeV) sources belongs to the class of active galactic nuclei (AGN), in particular the BL Lac sub-class. AGNs are characterized by an extremely bright and compact emission…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-15 Martin Raue , Lukasz Stawarz , Daniel Mazin , Pierre Colin , Michelle Hui , Matthias Beilicke , Craig Walker

The East Asian very-long-baseline interferometry (VLBI) Network (EAVN) is a rapidly evolving international VLBI array that is currently promoted under joint efforts among China, Japan, and Korea. EAVN aims at forming a joint VLBI Network by…

In this letter, we report on dual-frequency European VLBI Network (EVN) observations of the faintest and least luminous radio cores in Seyfert nuclei, going to sub-mJy flux densities and radio luminosities around 10^19 W/Hz. We detect radio…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Marcello Giroletti , Francesca Panessa

When comparing modern fundamental reference frames in the radio (International Celestial Reference Frame) and optical (Gaia), a couple of bright radio reference sources appear to have very large radio-optical offsets, from tens up to…

Astrophysics of Galaxies · Physics 2025-01-14 S. Frey , O. Titov , A. Melnikov , S. Lambert

Traditionally VLBI observations focus on a small patch of sky and image typically a few 100 mas around a bright source, which is often used to self-calibrate the data. High spectral and time resolution is needed to image a larger area, in…

We present the results of EVN polarization observations of fourteen GHz-Peaked-Spectrum (GPS) radio sources at 5 GHz. These sources were selected from bright GPS source samples and we aimed at finding Compact Symmetric Objects (CSOs). We…

Astrophysics · Physics 2016-08-30 Liu Xiang , Cormac Reynolds , Richard Strom , Daniele Dallacasa

Mini-extreme-mass-ratio inspirals (mini-EMRIs), composed of a stellar-mass compact object and a much lighter companion, are promising sources of continuous gravitational waves in the frequency band of ground-based interferometers such as…

General Relativity and Quantum Cosmology · Physics 2025-12-29 Zi-Xuan Wang , Gong Cheng , Ju Chen , Huai-Ke Guo , Andrew L. Miller

Eighteen days of MERLIN data and 42 hours of A-array VLA data at 1.4 GHz have been combined to image a 10-arcmin field centred on the Hubble Deep and Flanking Fields (HDF and HFF). A complete sample of 92 radio sources with 1.4-GHz flux…

I present an introductory review text, focusing on recent deep field studies using radio telescopes, including high-resolution, wide-field VLBI observations. The nature of the faint radio source population is discussed, taking into account…

Astrophysics · Physics 2009-11-10 M. A. Garrett

We present the results of a multi-wavelength study of blazars selected from the 5th ROMABZCAT catalog. We selected from this sample a subsample of 2435 objects having at least one counterpart in one of the three main archival X-ray…

We have developed a new phase referencing technique for high frequency VLBI observations. In conventional phase referencing, one interleaves short scans on a nearby phase calibrator between the target source observations. In fast frequency…

Astrophysics · Physics 2009-11-10 E. Middelberg , A. L Roy , R. C. Walker , H. Falcke

Aims. The X-ray luminous and radio-loud AGN SRGE J170245.3+130104 discovered at z $\sim$ 5.5 provides unique chances to probe the SMBH growth and evolution with powerful jets in the early Universe. Methods. We present 1.35 - 5.1 GHz Very…

In the time domain, the radio sky in particular along the Galactic plane direction may vary significantly because of various energetic activities associated with stars, stellar and supermassive black holes. Using multi-epoch Very Large…

High Energy Astrophysical Phenomena · Physics 2022-01-12 Jun Yang , Yongjun Chen , Leonid I. Gurvits , Zsolt Paragi , Aiyuan Yang , Xiaolong Yang , Zhiqiang Shen

We study the most central regions of AGN jets with an angular resolution of tens of micro-arcseconds using VLBI at millimeter wavelengths (mm-VLBI). We present and discuss a new 86 GHz VLBI survey of compact radio sources. We show new high…

Astrophysics · Physics 2007-08-30 T. P. Krichbaum , S. S. Lee , A. P. Lobanov , A. P. Marscher , M. A. Gurwell

Many low-luminosity active galactic nuclei (AGNs) contain a compact radio core which can be observed with high angular resolution using very long baseline interferometry (VLBI). Combining arcsec-scale structural information with…

Astrophysics of Galaxies · Physics 2020-04-06 Máté Krezinger , Sándor Frey , Zsolt Paragi , Roger Deane

Surveys at mm wavelengths emphasize rare classes of extragalactic radio sources characterized by spectra keeping flat or inverted up to high frequencies (such as blazars, GPS sources, advection dominated sources, or even gamma-ray burst…

We present an analysis of the detection fraction and the number counts of radio sources imaged with Very Long Baseline Interferometry (VLBI) at 1.4 GHz as part of the mJIVE-20 survey. From a sample of 24,903 radio sources identified by…

Astrophysics of Galaxies · Physics 2023-08-31 S. Rezaei , J. P. McKean , A. T. Deller , J. F. Radcliffe

We report the results of high-resolution 5 GHz Very Long Baseline Array and European VLBI Network observations of 36 nearby galaxies, an extension of the Legacy e-MERLIN Multi-band Imaging of Nearby Galaxies (LeMMINGs) survey. Our sample…

High Energy Astrophysical Phenomena · Physics 2025-02-19 Xiaopeng Cheng , Tao An , Willem Baan , Raneri D. Baldi , David R. A. Williams-Baldwin , Bong Won Sohn , Robert Beswick , Ian M. Mchardy

The European VLBI Network (EVN) has been used at two epochs in 2003 and 2009 to obtain multi-frequency high-resolution images of the merger galaxy NGC6240 in order to study the radio properties of all compact high-brightness components in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Y. Hagiwara , W. A. Baan , H. -R. Kloeckner