Related papers: A shrinking Compact Symmetric Object: J11584+2450?
We report on two optical candidates for the counterpart to an X-ray source in the SMC, 1WGA J0053.8-7226, identified as a serendipitous X-ray source from the ROSAT PSPC archive, and also observed by the Einstein IPC. Its X-ray properties,…
Relativistic jets are a common feature of radio loud active galactic nuclei. Multifrequency observations are a unique tool to constrain their physics. We report on a detailed study of the properties of the jet of the nearby BL Lac object…
Based on the FIRST and SDSS catalogues a flux density limited sample of weak Compact Steep Spectrum (CSS) sources with radio luminosity below 10^26 [W/Hz] at 1.4 GHz has been constructed. Our previous multifrequency observations of CSS…
Opacity-driven shifts of the apparent VLBI core position with frequency (the "core shift" effect) probe physical conditions in the innermost parts of jets in active galactic nuclei. We present the first detailed investigation of this effect…
We investigate the nature and classification of PMNJ1603-4904, a bright radio source close to the Galactic plane, which is associated with one of the brightest hard-spectrum gamma-ray sources detected by Fermi/LAT. It has previously been…
We discovered an X-ray cluster in a recent pointed Chandra observation of the radio-loud compact-steep-spectrum source 1321+045 at the redshift of 0.263. 1321+045 is part of larger survey which aims to study the X-rays properties of weak…
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…
According to a generally accepted paradigm, small intrinsic sizes of Compact Steep Spectrum (CSS) radio sources are a direct consequence of their youth, but in later stages of their evolution they are believed to become large-scale sources.…
We report on multi-band observations of the transient source Swift J0840.7-3516, which was detected in outburst in 2020 February by the Neil Gehrels Swift Observatory. The outburst episode lasted just ~5 days, during which the X-ray…
We present the results of a number of high resolution radio observations of the AGN 1156+295. These include multi-epoch and multi-frequency VLBI, VSOP, MERLIN and VLA observations made over a period of 50 months. The 5 GHz MERLIN images…
We present optical, X-ray and radio observations of the black hole transient (BHT) XTE J1752-223 towards and in quiescence. Optical photometry shows that the quiescent magnitude of XTE J1752-223 is fainter than 24.4 magnitudes in the…
Aims. We wish to clarify the origin of the multiple jet features emanating from the binary protostar SVS 13A (= VLA4A/VLA4B). Methods. We used the Plateau de Bure Interferometer to map at 0.3-0.8" (~70-190 au) dust emission at 1.4 mm,…
We report further results from our imaging survey at 15GHz (lambda=2 cm) with the Very Long Baseline Array. This paper presents single epoch images for 39 sources, bringing the total number of objects in the sample to 171. Our sample is…
We present a model to determine the physical parameters of jets and hot spots of a sample of CSOs under very basic assumptions like synchrotron emission and minimum energy conditions. Based on this model we propose a simple evolutionary…
We report results from Chandra observations of the X-ray jet of 3C~273 during the calibration phase in 2000 January. The zeroeth-order images and spectra from two 40-ks exposures with the HETG and LETG+ACIS-S show a complex X-ray structure.…
We present the first unambiguous case of external variability of a radio gravitational lens, CLASS B1600+434. The VLA 8.5-GHz difference light curve of the lensed images, taking the proper time-delay into account, shows the presence of…
This paper presents high-resolution ALMA observations of the massive young stellar object G25.65+1.05, which is known to host water maser super flares. To investigate the nature of compact continuum sources that have been previously…
We investigate the relativistic jet of the powerful radio-emitting blazar J1429+5406 at redshift z=3.015. Our understanding of jet kinematics in z>3 quasars is still rather limited, based on a sample of less than about 50 objects. The…
We have used the Very Large Array (VLA) to conduct a survey for radio continuum emission in the sample of 52 Seyfert nuclei selected from the optical spectroscopic galaxy catalog of Ho, Filippenko, and Sargent. This Seyfert sample is the…
We present a Chandra observation of the candidate BL Lac object EXO 0423.4-0840. The X-ray emission from EXO 0423.4-0840 is clearly extended, and is associated with an optical early-type galaxy, MCG-01-12-005, at the centre of cluster ClG…