0000000000697417
AUTHOR
D. Eisenacher
The blazar-like radio structure of the TeV source IC310
Context. The radio galaxy IC310 in the Perseus cluster has recently been detected in the gamma-ray regime at GeV and TeV energies. The TeV emission shows time variability and an extraordinarily hard spectrum, even harder than the spectrum of the similar nearby gamma-ray emitting radio galaxy M87. Aims. High-resolution studies of the radio morphology help to constrain the geometry of the jet on sub-pc scales and to find out where the high-energy emission might come from. Methods. We analyzed May 2011 VLBA data of IC310 at a wavelength of 3.6 cm, revealing the parsec-scale radio structure of this source. We compared our findings with more information available from contemporary single-dish fl…
TANAMI Blazars in the IceCube PeV Neutrino Fields
The IceCube Collaboration has announced the discovery of a neutrino flux in excess of the atmospheric background. Due to the steeply falling atmospheric background spectrum, events at PeV energies are most likely of extraterrestrial origin. We present the multiwavelength properties of the six radio brightest blazars positionally coincident with these events using contemporaneous data of the TANAMI blazar sample, including high-resolution images and spectral energy distributions. Assuming the X-ray to {\gamma}-ray emission originates in the photoproduction of pions by accelerated protons, the integrated predicted neutrino luminosity of these sources is large enough to explain the two detecte…
Multifrequency Studies of the Peculiar Quasar 4C +21.35 during the 2010 Flaring Activity
著者人数: 290名
Black hole lightning due to particle acceleration at subhorizon scales
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 …
The aftermath of an exceptional tev flare in the agn jet of ic 310
The nearby active galaxy IC 310 (z=0.019), located in the Perseus cluster of galaxies is a bright and variable multi-wavelength emitter from the radio regime up to very high gamma-ray energies above 100 GeV. Very recently, a blazar-like compact radio jet has been found by parsec-scale VLBI imaging. Along with the unusually flat gamma-ray spectrum and variable high-energy emission, this suggests that IC 310 is the closest known blazar and therefore a key object for AGN research. As part of an intense observing program at TeV energies with the MAGIC telescopes, an exceptionally bright flare of IC 310 was detected in November 2012 reaching a flux level of up to >0.5 Crab units above 300 GeV…