相关论文: Compact Symmetric Objects -- II Confirmation of a …
Compact symmetric objects (CSOs) are intrinsically compact extragalactic radio sources that are thought to be the progenitors of classical radio galaxies. To date, evolutionary models have mainly focused on the formation and growth of…
Most of the gamma-ray emitting active galactic nuclei (AGN) are blazars, although there is still a small fraction of non-blazar AGN in the Fermi/LAT catalog. Among these misaligned gamma-ray-emitting AGN, a few can be classified as Compact…
The $\gamma$-ray emitting compact symmetric objects (CSOs) PKS 1718--649, NGC 3894, and TXS 0128+554 are lobe-dominated in the radio emission. In order to investigate their $\gamma$-ray radiation properties, we analyze the $\sim$14-yr…
Compact steep-spectrum sources (CSSs) likely represent a population of young radio-loud active galactic nuclei (AGNs) and have been identified as gamma-ray emitting sources. We present a comprehensive analysis of their gamma-ray emission…
The evolutionary stage of a powerful radio source originated by an AGN is related to its linear size. In this context, compact symmetric objects (CSOs), which are powerful and intrinsically small (< 1 kpc) radio sources with a convex…
We present the kinematic properties of a type-2 QSO, SDSS J132323.33-015941.9 at z~0.35, based on the analysis of Very Large Telescope integral field spectroscopy and Hubble Space Telescope (HST) imaging, which suggest that the target is a…
We present the discovery of rare active galactic nuclei (AGNs) in nearby (z < 0.05) compact elliptical galaxies (cEs) located in isolated environments. Using spectroscopic data from the Sloan Digital Sky Survey (SDSS) Data Release 12, four…
Central compact objects (CCOs) are a handful of young neutron stars found at the center of supernova remnants (SNRs). They show high thermal X-ray luminosities but no radio emission. Spin-down rate measurements of the three CCOs with X-ray…
We explore host galaxy properties and environment of a sample of Type 1 and 2 active galactic nuclei (AGN) taken from the COSMOS2015 catalog, within 0.3 $\leq z \leq$ 1.1 selected for their emission in X-rays, optical spectra and SED…
The evolutionary stage of a powerful radio source originated by an AGN is related to its linear size. In this context, compact symmetric objects (CSOs), which are powerful and intrinsically small objects, should represent the young stage in…
The evolution of symmetric extragalactic radio sources can be characterized by four distinct growth stages of the radio luminosity versus size of the source. The interaction of the jet with the ambient medium results in the formation and…
We study a sample of 43 early-type galaxies, selected from the SDSS because they appeared to have velocity dispersion > 350 km/s. High-resolution photometry in the SDSS i passband using HRC-ACS on board the HST shows that just less than…
Highly collimated supersonic jets are observed to emerge from a wide variety of astrophysical objects, ranging from Active Nuclei of Galaxies (AGN's) to Young Stellar Objects (YSOs) within our own Galaxy. Despite their different physical…
The class of radio sources known as Compact Symmetric Objects (CSOs) is of particular interest in the study of the evolution of radio galaxies. CSOs are thought to be young (probably ~10^4 years), and a very high fraction of them exhibit HI…
We investigate the nature of low-luminosity radio-loud active galactic nuclei (RLAGN) selected from the LOFAR Two-metre Sky Survey (LoTSS) first data release (DR1). Using optical, mid-infrared, and radio data, we have conservatively…
Central Compact Objects (CCOs) are a handful of sources located close to the geometrical center of young supernova remnants. They only show thermal-like, soft X-ray emission and have no counterparts at any other wavelength. While the first…
We present pc-scale images of ten Compact Symmetric Objects (CSO) candidates observed with the European VLBI network (EVN). Five radio sources have been observed at 1.6 GHz, and five more at 2.3/8.4 GHz, the latter subsample with the…
We present results from the first intensive monitoring campaign of a sample of Compact Symmetric Objects (CSOs). We observed seven CSOs at 8.5 GHz over a period of eight months, with an average spacing between observations of 2.7 days. Our…
Compact Symmetric Objects (CSOs) have been observed with Chandra and XMM-Newton to gain insights into the initial stages of a radio source evolution and probe the black hole activity at the time of relativistic outflow formation. However,…
Compact symmetric objects (CSOs) trace the earliest phases of radio-galaxy growth; however, robust classification is difficult when radio cores are weak or invisible. We aim to develop and test a Gaia+VLBI approach that utilizes the…