534 citations · 6.9k across the 89 of their papers we have counts for
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Testing two-component models on very-high-energy gamma-ray emitting BL Lac objects
MAGIC Collaboration, V. A. Acciari, S. Ansoldi +201
Context. It has become evident that one-zone synchrotron self-Compton models are not always adequate for very-high-energy (VHE) gamma-ray emitting blazars. While two-component mode…
Long-term optical monitoring of TeV emitting Blazars
K. Nilsson, E. Lindfors, L. O. Takalo +17
We present 10 years of R-band monitoring data of 31 northern blazars which were either detected at very high energy (VHE) gamma rays or listed as potential VHE gamma-ray emitters.…
Authenticating the Presence of a Relativistic Massive Black Hole Binary in OJ 287 Using its General Relativity Centenary Flare: Improved Orbital Parameters
Lankeswar Dey, M. J. Valtonen, A. Gopakumar +5
Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show…
The broad-band properties of the intermediate synchrotron peaked BL Lac S2 0109+22 from radio to VHE gamma rays
MAGIC Collaboration, S. Ansoldi, L. A. Antonelli +163
The MAGIC telescopes observed S2 0109+22 in 2015 July during its flaring activity in high energy gamma rays observed by Fermi-LAT. We analyse the MAGIC data to characterise the ver…
Stochastic modeling of multiwavelength variability of the classical BL Lac object OJ 287 on timescales ranging from decades to hours
A. Goyal, L. Stawarz, S. Zola +109
We present the results of our power spectral density analysis for the BL Lac object OJ\,287, utilizing the {\it Fermi}-LAT survey at high-energy -rays, {\it Swift}-XRT in X-rays…
Gamma-ray and Optical Oscillations of 0716+714, MRK 421, and BL Lac
A. Sandrinelli, S. Covino, A. Treves +12
We examine the 2008-2016 -ray and optical light curves of three bright BL Lac objects, 0716+714, MRK 421, BL Lac, which exhibit large structured variability. We searched for per…
A luminous and isolated gamma-ray flare from the blazar B2 1215+30
VERITAS Collaboration, A. U. Abeysekara, S. Archambault +84
B2 1215+30 is a BL Lac-type blazar that was first detected at TeV energies by the MAGIC atmospheric Cherenkov telescopes, and subsequently confirmed by the VERITAS observatory with…
The RINGO2 and DIPOL Optical Polarisation Catalogue of Blazars
H. Jermak, I. A. Steele, E. Lindfors +9
We present ~2000 polarimetric and ~3000 photometric observations of 15 gamma-ray bright blazars over a period of 936 days (11/10/2008 - 26/10/2012) using data from the Tuorla blaza…
Optical and Radio variability of the Northern VHE gamma-ray emitting BL Lac objects
E. J. Lindfors, T. Hovatta, K. Nilsson +9
We compare the variability properties of very high energy gamma-ray emitting BL Lac objects in the optical and radio bands. We use the variability information to distinguish multip…
A significant hardening and rising shape detected in the MeV/GeV nuFnu spectrum from the recently-discovered very-high-energy blazar S4 0954+65 during the bright optical flare in 2015 February
Y. T. Tanaka, J. Becerra Gonzalez, R. Itoh +18
We report on Fermi Large Area Telescope (LAT) and multi-wavelength results on the recently-discovered very-high-energy (VHE, 100 GeV) blazar S4 0954+65 () during an e…
Multi-Wavelength Observations of the Blazar 1ES 1011+496 in Spring 2008
The MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +158
The BL Lac object 1ES 1011+496 was discovered at Very High Energy gamma-rays by MAGIC in spring 2007. Before that the source was little studied in different wavelengths. Therefore…
Primary black hole spin in OJ287 as determined by the General Relativity centenary flare
M. J. Valtonen, S. Zola, S. Ciprini +87
OJ287 is a quasi-periodic quasar with roughly 12 year optical cycles. It displays prominent outbursts which are predictable in a binary black hole model. The model predicted a majo…
Insights into the emission of the blazar 1ES 1011+496 through unprecedented broadband observations during 2011 and 2012
J. Aleksić, S. Ansoldi, L. A. Antonelli +161
1ES 1011+496 was discovered in very high energy (VHE, E >100 GeV) -rays with MAGIC in 2007. The absence of simultaneous data at lower energies led to a rather incomp…
Investigating the peculiar emission from the new VHE gamma-ray source H1722+119
MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +159
The MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov) telescopes observed the BL Lac object H1722+119 (redshift unknown) for six consecutive nights between 2013 May 17 and 22,…
Polarization angle swings in blazars: The case of 3C 279
S. Kiehlmann, T. Savolainen, S. G. Jorstad +61
Over the past few years, several occasions of large, continuous rotations of the electric vector position angle (EVPA) of linearly polarized optical emission from blazars have been…
Multiwavelength Study of Quiescent States of Mrk 421 with Unprecedented Hard X-Ray Coverage Provided by NuSTAR in 2013
M. Baloković, D. Paneque, G. Madejski +305
We present coordinated multiwavelength observations of the bright, nearby BL Lac object Mrk 421 taken in 2013 January-March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, V…
Locating the gamma-ray emission site in Fermi/LAT blazars. II Multifrequency correlations
V. Ramakrishnan, T. Hovatta, M. Tornikoski +6
In an attempt to constrain and understand the emission mechanism of gamma rays, we perform a cross-correlation analysis of 15 blazars using light curves in millimetre, optical and…
Multiwavelength Evidence for Quasi-periodic Modulation in the Gamma-ray Blazar PG 1553+113
The Fermi LAT collaboration, M. Ackermann, M. Ajello +139
We report for the first time a gamma-ray and multi-wavelength nearly-periodic oscillation in an active galactic nucleus. Using the Fermi Large Area Telescope (LAT) we have discover…
Teraelectronvolt pulsed emission from the Crab pulsar detected by MAGIC
MAGIC Collaboration, S. Ansoldi, L. A. Antonelli +139
Aims: To investigate the extension of the very-high-energy spectral tail of the Crab pulsar at energies above 400 GeV. Methods: We analyzed 320 hours of good quality data of…
First NuSTAR Observations of Mrk 501 within a Radio to TeV Multi-Instrument Campaign
A. Furniss, K. Noda, S. Boggs +273
We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 1 April and 10 August 2013, including the first detailed characterization of the s…
Very-high-energy γ-ray observations of novae and dwarf novae with the MAGIC telescopes
MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +148
Context. In the last five years the Fermi Large Area Telescope (LAT) instrument detected GeV γ-ray emission from five novae. The GeV emission can be interpreted in terms of an inve…
The 2009 multiwavelength campaign on Mrk 421: Variability and correlation studies
MAGIC Collaboration, J. Aleksić, S. Ansoldi +270
We performed a 4.5-month multi-instrument campaign (from radio to VHE gamma rays) on Mrk421 between January 2009 and June 2009, which included VLBA, F-GAMMA, GASP-WEBT, Swift, RXTE…
MAGIC observations of MWC 656, the only known Be/BH system
J. Aleksić, S. Ansoldi, L. A. Antonelli +149
Context: MWC 656 has recently been established as the first observationally detected high-mass X-ray binary system containing a Be star and a black hole (BH). The system has been a…
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…