464 citations · 9.7k across the 212 of their papers we have counts for
152 papers · 1 filter
mm-jets in the multi-messenger era
Karri I. I. Koljonen, Thomas D. Russell, Britton Jeter +16
Jets and outflows operate across the full cosmic mass scale from young stellar objects (YSOs) and X-ray binaries (XRBs) to active galactic nuclei (AGN), gamma-ray bursts (GRBs), an…
Multiband ALMA polarimetry of the jet base and kiloparsec-scale jet of 3C 273: A multicomponent Faraday structure in the nucleus
T. Hovatta, S. P. O'Sullivan, I. Marti-Vidal +1
Polarization observations at millimeter wavelengths can be used to study magnetized plasma in jets launched by supermassive black holes. We used multiband Atacama Large Millimeter…
SKA-VLBI Probes of High-energy Emission Processes in Relativistic Jets
M. Kadler, E. K. Bempong-Manful, P. G. Edwards +10
Relativistic jets in the nuclei of active galaxies are ubiquitous sources of high-energy emission. In particular, blazars represent the most luminous persistent X-ray and gamma-ray…
Investigating Active Galactic Nuclei variability with the Cherenkov Telescope Array Observatory
G. Grolleron, J. Biteau, M. Cerruti +21
Blazars, a type of active galactic nuclei (AGN) with relativistic jets pointed at the observer, exhibit flux variability across the electromagnetic spectrum due to particle acceler…
Compelling Evidence for a Harmonic in the Light Curve of the Supermassive Black Hole Binary Candidate PKS J1309+1154
A. C. S. Readhead, M. F. Aller, A. G. Sullivan +23
We recently discovered a supermassive black hole binary (SMBHB) candidate, PKS J1309+1154, in the combined 46-yr University of Michigan Radio Astronomy Observatory (UMRAO) plus Owe…
A Search for Supermassive Black Hole Binary Candidates in 46-Year Radio Light Curves of 83 Blazars
B. Molina, P. Mróz, P. V. De la Parra +23
The combined University of Michigan Radio Astronomy Observatory (UMRAO) and Owens Valley Radio Observatory (OVRO) blazar monitoring programs at 14.5/15 GHz provide uninterrupted li…
Association of the IceCube neutrinos with CAZ blazar light curves
Pouya M. Kouch, Talvikki Hovatta, Elina Lindfors +3
The IceCube Neutrino Observatory has detected several hundred high-energy neutrinos from cosmic sources. Despite numerous studies searching for their origin, it is still not known…
CAZ catalog and optical light curves of 7918 blazar-selected active galactic nuclei
Pouya M. Kouch, Elina Lindfors, Talvikki Hovatta +10
Active galactic nuclei (AGN) are some of the brightest and most variable objects in the Universe. Those with relativistic jets observed at small viewing angles are blazars. Due to…
Pinpointing the location of the gamma-ray emitting region in the FSRQ 4C+01.28
F. Rösch, M. Kadler, E. Ros +5
The FSRQ 4C+01.28 is a bright and highly variable radio and -ray emitter. We aim to pinpoint the location of the -ray emitting region within its jet in order to derive strong…
IXPE Observations of the Blazar Mrk 501 in 2022: A Multiwavelength View
L. Lisalda, E. Gau, H. Krawczynski +157
The blazar Markarian 501 (Mrk 501) was observed on three occasions over a 4-month period between 2022 March and 2022 July with the Imaging X-ray Polarimetry Explorer (IXPE). In thi…
Very-high-energy gamma-ray detection and long-term multi-wavelength view of the flaring blazar B2 1811+31
K. Abe, S. Abe, J. Abhir +231
Among the blazars whose emission has been detected up to very-high-energy (VHE; 100 GeV < E < 100 TeV) gamma rays, intermediate synchrotron-peaked BL Lacs (IBLs) are quite rare. Th…
Optimizing the hunt for extraterrestrial high-energy neutrino counterparts
Pouya M. Kouch, Elina Lindfors, Talvikki Hovatta +6
It has been a decade since the IceCube collaboration began detecting high-energy (HE) neutrinos originating from cosmic sources. Despite a few well-known individual associations an…
Characterizing Candidate Blazar Counterparts of the Ultra-High-Energy Event KM3-230213A
KM3NeT Collaboration, MessMapp Group, LAT Collaboration +13
High-energy astrophysical neutrinos serve as crucial messengers for understanding hadronic acceleration processes and identifying the origins of cosmic rays, with blazars among the…
The polarisation behaviour of OJ 287 viewed through radio, millimetre and optical observations between 2015 and 2017
J. Jormanainen, T. Hovatta, E. Lindfors +13
OJ 287 is a bright blazar with century-long observations, and one of the strongest candidates to host a supermassive black hole binary. Its polarisation behaviour between 2015 and…
Time-dependent modelling of short-term variability in the TeV-blazar VER J0521+211 during the major flare in 2020
MAGIC Collaboration, S. Abe, J. Abhir +228
The BL Lacertae object VER J0521+211 underwent a notable flaring episode in February 2020. A short-term monitoring campaign, led by the MAGIC (Major Atmospheric Gamma Imaging Chere…
Multi-wavelength study of OT 081: broadband modelling of a transitional blazar
MAGIC Collaboration, H. Abe, S. Abe +270
OT 081 is a well-known, luminous blazar that is remarkably variable in many energy bands. We present the first broadband study of the source which includes very-high-energy (VHE, $…
PKS~J08050111: A Second Owens Valley Radio Observatory Blazar Showing Highly Significant Sinusoidal Radio Variability -- The Tip of the Iceberg
P. V. de la Parra, S. Kiehlmann, P. Mroz +23
Owens Valley Radio Observatory (OVRO) observations of supermassive black hole binary (SMBHB) candidate PKS~2131021 revealed, for the first time, six likely characteristics of th…
Association of the IceCube neutrinos with blazars in the CGRaBS sample
Pouya M. Kouch, Elina Lindfors, Talvikki Hovatta +11
The origin of high-energy (HE) astrophysical neutrinos has remained an elusive hot topic in the field of HE astrophysics for the past decade. Apart from a handful of individual ass…
PKS 2131-021 -- Discovery of Strong Coherent Sinusoidal Variations from Radio to Optical Frequencies: Compelling Evidence for a Blazar Supermassive Black Hole Binary
S. Kiehlmann, P. V. de la Parra, A. G. Sullivan +31
Haystack and Owens Valley Radio Observatory (OVRO) observations recently revealed strong, intermittent, sinusoidal total flux-density variations that maintained coherence between 1…
Galactic transient sources with the Cherenkov Telescope Array Observatory
Cherenkov Telescope Array Observatory Consortium
A wide variety of Galactic sources show transient emission at soft and hard X-ray energies: low- and high-mass X-ray binaries containing compact objects, isolated neutron stars exh…
Broadband Multi-wavelength Properties of M87 during the 2018 EHT Campaign including a Very High Energy Flaring Episode
J. C. Algaba, M. Balokovic, S. Chandra +738
The nearby elliptical galaxy M87 contains one of the only two supermassive black holes whose emission surrounding the event horizon has been imaged by the Event Horizon Telescope (…
Distinguishing radiation mechanisms and particle populations in blazar jets through long-term multi-band monitoring with RINGO3 and Fermi
Callum McCall, Helen Jermak, Iain A. Steele +6
We present the results of seven years of multicolour photometric monitoring of a sample of 31 -ray bright blazars using the RINGO3 polarimeter on the Liverpool Telescope from 20…
The variability patterns of the TeV blazar PG 1553+113 from a decade of MAGIC and multi-band observations
MAGIC Collaboration, H. Abe, S. Abe +264
PG 1553+113 is one of the few blazars with a convincing quasi-periodic emission in the gamma-ray band. The source is also a very high-energy (VHE; >100 GeV) gamma-ray emitter. To b…
Insights into the broad-band emission of the TeV blazar Mrk 501 during the first X-ray polarization measurements
S. Abe, J. Abhir, V. A. Acciari +260
We present the first multi-wavelength study of Mrk 501 including very-high-energy (VHE) gamma-ray observations simultaneous to X-ray polarization measurements from the Imaging X-ra…