Related papers: A Multi-Frequency Study of 3C309.1
The "core" of a radio source is believed to mark the frequency-dependent location where the optical depth to synchrotron self--absorption tau_s~1. The frequency dependence can be used for derive physical conditions of the radio emitting…
We present multi-frequency observational results for the Compact Steep-Spectrum (CSS) quasar 3C309.1. The observations were carried out with the VSOP at 1.6 and 4.8GHz and the VLBA at 15.4GHz. The source has a distorted, one-sided radio…
The apparent position of the "core" in a parsec-scale radio jet (a compact, bright emitting region at the narrow end of the jet) depends on the observing frequency, owing to synchrotron self-absorption and external absorption. While…
In extragalactic jets, the apparent position of the bright/narrow end (the core) depends on the observing frequency, owing to synchrotron self-absorption and external absorption. The effect must be taken into account in order to achieve…
We present the results of six-epoch Very Long Baseline Array (VLBA) observations of 3C~66A. The high-resolution Very Long Baseline Interferometer (VLBI) maps obtained at multi-frequency (2.3, 8.4, and 22.2 GHz) simultaneously enabled us to…
One of the most well-known extragalactic sources in the sky, quasar 3C 454.3, shows a curved parsec-scale jet that has been exhaustively monitored with very-long-baseline interferometry (VLBI) over the recent years. In this work, we present…
We present the multi-frequency, multi-epoch Very Long Baseline Interferometry (VLBI) study of the two-sided jets in the low-luminosity active galactic nucleus NGC 3998, where physical properties of the jets on parsec scales remain poorly…
We present results from very-long-baseline-interferometry (VLBI) observations of the nucleus in the lobe-dominated quasar 3C207. These observations were completed at 8.4 or 10.7 GHz (X-band) from 1981 to 2010, spanning 29 years. The nucleus…
Previous spectral energy distribution modeling based on XMM-Newton X-ray observation of the classical double-lobed radio galaxy 3C 411 left the possibility open for the presence of a blazar-like core. We investigated this scenario by…
We present the analysis of VLA and VLBA observations of the radio source 3C 338, associated with the cD galaxy NGC 6166, the central dominant galaxy of the cluster Abell 2199. The VLBA observations were done at 8.4 and 15.4 GHz, while the…
We present Very Long Baseline Array (VLBA) observations of the radio source J1625+4134 at 22 and 15 GHz and analyze them in concurrence with other existing VLBI data on this source. The high resolution images at 15 and 22 GHz show a short…
We present new results on the parsec-scale jet of the quasar 3C395, derived from VLBI polarization sensitive observations made in 1995.91 and 1998.50 at 8.4, 15.4 and 22.2 GHz. The observations show a complex one-sided jet extending up to…
We present the first 86 GHz VLBI observations of the radio galaxy 3C~120, together with contemporaneous 43 and 22 GHz polarimetric VLBA observations. The very high angular resolution obtained at 86 GHz provides an upper limit to the size of…
Multi-frequency Very Long Baseline Array (VLBA) polarimetry observation of the GHz-Peaked Spectrum (GPS) quasar OQ172 (J1445+0958) has been performed at 1.6, 2.2, 4.8, 8.3 and 15.3 GHz in 2005. Core-jet structures are detected in all bands…
We present multi--frequency radio observational results of the quasar 3C~48. The observations were carried out with the Very Large Array (VLA) at five frequencies of 0.33, 1.5, 4.8, 8.4, and 22.5 GHz, and with the Multi--Element Radio…
We present new more sensitive high-resolution radio observations of a compact broad absorption line (BAL) quasar, 1045+352, made with the EVN+MERLIN at 5 GHz. They allowed us to trace the connection between the arcsecond structure and the…
The results of VLBI observations of the quasar 3C273, obtained during a multi-frequency campaign in late 1992 in the radio, millimeter and X-ray bands are presented and discussed. The VLBI observations were made at 22 GHz with a Global…
Using a combination of observations involving the VLA, MERLIN and global VLBI networks we have made a detailed study of the radio continuum and the neutral hydrogen (HI) kinematics and distribution within the central kiloparsec of the radio…
We carried out a multifrequency and multiepoch study of the highly polarized quasar, PKS 1502+106 at radio frequencies. The analysis is based on an EVN dataset at 5 GHz, archive VLBA datasets at 2.3, 8.3, 24.4 and 43.1 GHz and an archive…
The long-term evolution of the synchrotron emission from the parsec-scale jet in the quasar 3C345 is analysed, on the basis of multi-frequency monitoring with very long baseline interferometry (VLBI) and covering the period 1979-1994. We…