Search results for "X-shaped radio galaxy"
showing 5 items of 5 documents
Black hole lightning due to particle acceleration at subhorizon scales
2015
Supermassive black holes with masses of millions to billions of solar masses are commonly found in the centers of galaxies. Astronomers seek to image jet formation using radio interferometry, but still suffer from insufficient angular resolution. An alternative method to resolve small structures is to measure the time variability of their emission. Here, we report on gamma-ray observations of the radio galaxy IC 310 obtained with the MAGIC telescopes revealing variability with doubling time scales faster than 4.8 min. Causality constrains the size of the emission region to be smaller than 20\% of the gravitational radius of its central black hole. We suggest that the emission is associated …
Three Peculiar Objects From a New Sample of Radio Galaxies
2001
We have constructed a new sample of 84 large angular size radio galaxies selected from the NRAO VLA Sky Survey (NVSS). Radio sources with declination above +60°, total flux density greater than 100 mJy at 1.4 GHz and angular size larger then 4′ have been selected and observed with the VLA at 1.4 and 4.9 GHz. A number of peculiar radio galaxies have been discovered, of which we present here results on J1835+620, J2114+820 and J2157+664.
VLBI Observations of FRI Radio Galaxies
1996
The Fanaroff-Riley type I radio galaxies (Fanaroff & Riley, 1974) presented in this paper belong to the complete sample of low-intermediate luminosity radio galaxies published in Giovannini, Feretti & Comoretto (1990). This sample includes radio galaxies with different morphologies on the arcsecond scale, such as compact sources, core-halos, FRIs and FRIIs.
VLBI Observations of Radio Galaxies
1994
We undertook a project of observation of a complete sample of radio galaxies with the VLBI technique, in order to test: a) current models on jet dynamics and b) the radio source unified schemes. A preliminary analysis based on the data obtained by us for 10 galaxies of our sample indicates that the parsec scale structure in low power radio galaxies (FR-I) and high power radio galaxies (FR-II) is essentially the same.
VLBI Observations of a Complete Sample of Radio Galaxies. VII. Study of the FR I Sources 3C 31, 4C 35.03, and 3C 264
1997
We present results from global VLBI and VLA observations of three FanaroU-Riley type I radio gal- axies, 3C 31, 4C 35.03, and 3C 264, at a frequency of 5 GHz. In all three cases, we observe asymmetric parsec-scale structures consisting of a compact core and a single jet pointing in the direction of the more prominent kiloparsec jet. We interpret such alignment as evidence for the relativistic nature of FR I radio jets at parsec scales. Comparing the VLBI and VLA images of these sources, we —nd a progressive deceleration of the plasma —ow from parsec to kiloparsec scales. We consider another —ve FR I radio galaxies studied previously by us and —nd that, in a set of eight FR I objects, the es…