593 citations · 28.6k across the 519 of their papers we have counts for
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Black hole lightning due to particle acceleration at subhorizon scales
MAGIC Collaboration, J. Aleksić, S. Ansoldi +151
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 inte…
Unprecedented study of the broadband emission of Mrk 421 during flaring activity in March 2010
The MAGIC Collaboration, J. Aleksić, S. Ansoldi +251
A flare from the TeV blazar Mrk 421, occurring in March 2010, was observed for 13 consecutive days from radio to very high energy (VHE, E > 100 GeV) gamma-rays with MAGIC, VERITAS,…
The power of relativistic jets is larger than the luminosity of their accretion disks
G. Ghisellini, F. Tavecchio, L. Maraschi +2
Theoretical models for the production of relativistic jets from active galactic nuclei predict that jet power arises from the spin and mass of the central black hole, as well as th…
High-energy cosmic neutrinos from spine-sheath BL Lac jets
F. Tavecchio, G. Ghisellini
We recently proposed that structured (spine-sheath) jets associated to BL Lac objects offer a suitable environment for the production of the extragalactic high-energy ( TeV)…
No axions from the Sun
M. Roncadelli, F. Tavecchio
Preliminary evidence of solar axions in XMM-Newton observations has quite recently been claimed by Fraser et al. as an interpretation of their detection of a seasonally-modulated e…
Discovery of very high energy gamma-ray emission from the blazar 1ES 0033+595 by the MAGIC telescopes
J. Aleksić, S. Ansoldi, L. A. Antonelli +157
The number of known very high energy (VHE) blazars is , which is very small in comparison to the number of blazars detected in other frequencies. This situation is a hand…
Multiwavelength observations of Mrk 501 in 2008
MAGIC Collaboration, J. Aleksić, S. Ansoldi +256
Mrk 501 is one of the brightest blazars at TeV energies and has been extensively studied since its first VHE detection in 1996. Our goal is to characterize in detail the source gam…
Blazar candidates beyond redshift 4 observed by Swift
T. Sbarrato, G. Ghisellini, G. Tagliaferri +4
We have selected SDSS J222032.50+002537.5 and SDSS J142048.01+120545.9 as best blazar candidates out of a complete sample of extremely radio-loud quasars at z>4, with highly massiv…
Hints for an axion-like particle from PKS 1222+216?
Giorgio Galanti, Marco Roncadelli, Fabrizio Tavecchio +1
Flat spectrum radio quasars (FSRQs) are a particular class of blazars rich of optical/ultraviolet photons inside the broad line region (BLR), necessarily implying a huge optical de…
First broadband characterization and redshift determination of the VHE blazar MAGIC J2001+439
MAGIC Collaboration, J. Aleksić, S. Ansoldi +167
We aim to characterize the broadband emission from 2FGL J2001.1+4352, which has been associated with the unknown-redshift blazar MG4 J200112+4352. Based on its gamma-ray spectral p…
Photon-ALP conversions inside AGN
F. Tavecchio, G. Galanti, M. Roncadelli
An intriguing possibility to partially circumvent extragalactic background light (EBL) absorption in very-high-energy (VHE) observations of blazars is that photons convert into axi…
The major upgrade of the MAGIC telescopes, Part I: The hardware improvements and the commissioning of the system
MAGIC Collaboration, J. Aleksic, S. Ansoldi +162
The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. The telescopes are designed to measure Cherenkov light from…
The major upgrade of the MAGIC telescopes, Part II: A performance study using observations of the Crab Nebula
MAGIC Collaboration, J. Aleksic, S. Ansoldi +163
MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary island of La Palma, Spain. During summer 2011 and 2012 it underwent a series of upgrades, in…
Structured jets in BL Lac objects: efficient PeV neutrino factories?
F. Tavecchio, G. Ghisellini, D. Guetta
The origin of the high-energy neutrinos (0.11 PeV range) detected by IceCube remains a mystery. In this work we explore the possibility that efficient neutrino production can oc…
Probing the very-high-energy gamma-ray spectral curvature in the blazar PG 1553+113 with the MAGIC telescopes
MAGIC Collaboration, J. Aleksić, S. Ansoldi +152
PG 1553+113 is a very-high-energy (VHE, ) -ray emitter classified as a BL Lac object. Its redshift is constrained by intergalactic absorption lines in the r…
MAGIC search for VHE -ray emission from AE Aquarii in a multiwavelength context
J. Aleksić, S. Ansoldi, L. A. Antonelli +152
It has been claimed that the nova-like cataclysmic variable (CV) AE Aquarii (AE Aqr) is a very-high-energy (VHE, 100 GeV) source both on observational and theoretical grounds.…
Measurement of the Crab Nebula spectrum over three decades in energy with the MAGIC telescopes
MAGIC Collaboration, J. Aleksić, S. Ansoldi +150
The MAGIC stereoscopic system collected 69 hours of Crab Nebula data between October 2009 and April 2011. Analysis of this data sample using the latest improvements in the MAGIC st…
Photons to axion-like particles conversion in Active Galactic Nuclei
Fabrizio Tavecchio, Marco Roncadelli, Giorgio Galanti
The idea that photons can convert into axion-like particles (ALPs) in or around an AGN and reconvert back into photons in the Milky Way magnetic field has been p…
Discovery of TeV gamma-ray emission from the pulsar wind nebula 3C 58 by MAGIC
MAGIC Collaboration, J. Aleksić, S. Ansoldi +145
The pulsar wind nebula (PWN) 3C 58 is one of the historical very-high-energy (VHE; E>100 GeV) gamma-ray source candidates. It is energized by one of the highest spin-down power pul…
Polarimetric Tomography of Blazar Jets
Ulisses Barres de Almeida, Fabrizio Tavecchio, Nijil Mankuzhiyil
In this paper we propose a way to use optical polarisation observations to provide independent constraints and guide to the modelling of the spectral energy distribution (SED) of b…
On the spine-layer scenario for the very high-energy emission of NGC 1275
F. Tavecchio, G. Ghisellini
We discuss the -ray emission of the radiogalaxy NGC 1275 (the central galaxy of the Perseus Cluster), detected by Fermi-LAT and MAGIC, in the framework of the "spine-layer" scen…
Multifrequency Studies of the Peculiar Quasar 4C +21.35 During the 2010 Flaring Activity
M. Ackermann, M. Ajello, A. Allafort +288
The discovery of rapidly variable Very High Energy (VHE; E > 100 GeV) gamma-ray emission from 4C +21.35 (PKS 1222+216) by MAGIC on 2010 June 17, triggered by the high activity dete…
SDSS J114657.79+403708.6: the third most distant blazar at z=5.0
G. Ghisellini, T. Sbarrato, G. Tagliaferri +5
The radio-loud quasar SDSS J114657.79+403708.6 at a redshift z=5.0 is one of the most distant radio-loud objects. The IR-optical luminosity and spectrum suggest that its black hole…
Search for Very-High-Energy Gamma Rays from the z = 0.896 Quasar 4C +55.17 with the MAGIC telescopes
MAGIC Collaboration, J. Aleksić, S. Ansoldi +157
The bright gamma-ray quasar 4C +55.17 is a distant source () with a hard spectrum at GeV energies as observed by the Large Area Telescope (LAT) on board the {\it Fermi}…