相关论文: Significant Limb-Brightening in the Inner Parsec o…

We present the first polarimetric space VLBI imaging observations at 22 GHz. BL Lacertae was observed in 2013 November 10 with the RadioAstron space VLBI mission, including a ground array of 15 radio telescopes. The instrumental…

In this paper we present a multifrequency and multiepoch study of \object{PKS 1502+106} at radio frequencies. The analysis is based on an EVN (European VLBI Network) dataset at 5 GHz and archive VLBA (Very Long Baseline Array) datasets at…

We present a comprehensive 5-43 GHz VLBA study of the blazar 3C 273 initiated after an onset of a strong $\gamma$-ray flare in this source. We have analyzed the kinematics of new-born components, light curves, and position of the apparent…

We present thirty VLBI images of the TeV blazar Markarian 421 (1101+384) at fifteen epochs spanning the time range from 1994 to 1997, and at six different frequencies from 2.3 to 43 GHz. The imaged observations include a high-resolution 5…

The quasar 3C~286 is one of two compact steep spectrum sources detected by the {\it Fermi}/LAT. Here, we investigate the radio properties of the parsec(pc)-scale jet and its (possible) association with the $\gamma$-ray emission in 3C~286.…

Radio observations of the M87 jet reveal limb-brightened features that exhibit temporal variations, with the brighter limb side not remaining consistently fixed at the subparsec scales. Utilizing a force-free jet model that considers…

Nearby radio galaxies that contain jets are extensively studied with VLBI, addressing jet launching and the physical mechanisms at play around massive black holes. 3C 84 is unique in this regard, because the combination of its proximity and…

We present images of NRAO530 observed with the EVN (VLBI) at 5 GHz, the MERLIN at 1 .6 and 5 GHz, and the VLA at 5 and 8 GHz showing the complex morphology on scales from pc to kpc. The VLBI image shows a core-jet structure indicating a…

(Abridged) We investigate the flux density variability and changes in the parsec-scale radio structure of the flat spectrum radio quasar PKS 1510-089. This source was target of multi-epoch VLBI and Space-VLBI observations at 4.8, 8.4 and 22…

We present RadioAstron Space VLBI imaging observations of the BL Lac object S5 0716+71 made on January 3-4 2015 at a frequency of 22 GHz (wavelength $\lambda=1.3$ cm). The observations were made in the framework of the AGN Polarization Key…

We have studied the inner regions of the LINER galaxy NGC1052 since the mid 1990s at high resolution with 15 GHz very-long-baseline interferometry observations. A compact, two-sided jet structure is revealed, with multiple sub-parsec scale…

When a radio jet is partially optically thick in the launching region, its apparent compact core may display frequency-dependent positional shifts. High-precision astrometric measurements of core shifts enable astronomers to pinpoint the…

Previous VLBI kinematic studies of the blazar 3C 66A have unveiled complex jet kinematic behaviors. Using follow-up high-resolution VLBI observations and archival data, we investigate the morphology and the variations in orientation and…

Ground-space interferometer RadioAstron provides unique opportunity to probe detail structure of the distant active galactic nuclei at $\mu$as scales. Here we report on RadioAstron observations of the BL Lac object S5 0716$+$71, performed…

We present 23 interferometric images of parsec-scale jet of the quasar PKS 1741--03 at 15, 24 and 43 GHz spanning about 13 yr. We model the images as a superposition of discrete two--dimensional elliptical Gaussian components, with…

A sub-parsec scale radio counterjet has been detected in the nucleus of the closest radio galaxy, Centaurus A (NGC 5128), with VLBI imaging at 2.3 and 8.4 GHz. This is one of the first detections of a VLBI counterjet and provides new…

We analyze a single-epoch Global mm-VLBI Array (GMVA) observation of the blazar BL Lacertae (BL Lac) at 86 GHz from April 2021. The participation of the upgraded, phased Northern Extended Millimetre Array (NOEMA) adds additional sensitivity…

Parsec scale jet properties are shortly presented and discussed. Observational data are used to derive constraints on the jet velocity and orientation, the presence of velocity structures, and the connection between the pc and kpc scale.…

We present images from a long term program (MOJAVE: Monitoring of Jets in AGN with VLBA Experiments) to survey the structure and evolution of parsec-scale jet phenomena associated with bright radio-loud active galaxies in the northern sky.…

We present results from the first 22 GHz space very-long-baseline interferometric (VLBI) imaging observations of M87 by RadioAstron. As a part of the Nearby AGN Key Science Program, the source was observed in Feb 2014 at 22 GHz with 21…