IXPE observations of the blazar Mrk 501 in 2022: a multiwavelength view
Journal article, 2026
The blazar Markarian 501 (Mrk 501) was observed on three occasions over a 4-month period between 2022 March and July with the Imaging X-ray Polarimetry Explorer (IXPE). In this paper, we report for the first time on the third IXPE observation, performed between 2022 July 9 and 12, during which IXPE detected a linear polarization degree of (Formula presented) per cent at a polarization angle, measured east of north, of (Formula presented) within the 2 – 8 keV X-ray band. The X-ray polarization angle and degree during this observation are consistent with those obtained during the first two observations. The chromaticity of the polarization across radio, optical, and X-ray bands is likewise consistent with the result from the simultaneous campaigns during the first two observations. Furthermore, we present two types of models to explain the observed spectral energy distributions (SEDs) and energy-resolved polarization: a synchrotron self-Compton model with an anisotropic magnetic field probability distribution in the emitting volume, as well as an energy-stratified shock model. Our results support both the shock scenario as well as support that small levels of magnetic field anisotropy can explain the observed polarization.
polarization
radiation mechanisms: non-thermal
techniques: spectroscopic
BL Lacertae objects: individual: Mrk501
galaxies: active
galaxies: jets
Author
L. Lisalda
Washington University in St. Louis
E. Gau
Washington University in St. Louis
H. Krawczynski
Washington University in St. Louis
F. Tavecchio
Istituto nazionale di astrofisica (INAF)
I. Liodakis
University of Turku
A. Gokus
Washington University in St. Louis
N. Rodriguez Cavero
Washington University in St. Louis
Michael A. Nowak
Washington University in St. Louis
M. Negro
Louisiana State University
R. Middei
Agenzia Spaziale Italiana
M. Perri
Agenzia Spaziale Italiana
Simonetta Puccetti
Agenzia Spaziale Italiana
S.G. Jorstad
Boston University
I. Agudo
Spanish National Research Council (CSIC)
A. Marscher
Boston University
Beatriz Agís-González
Spanish National Research Council (CSIC)
A.V. Berdyugin
University of Turku
M. Bernardos
Spanish National Research Council (CSIC)
D. Blinov
University of Crete
G. Bonnoli
Istituto nazionale di astrofisica (INAF)
G.A. Borman
Crimean Astrophysical Observatory
I.G. Bourbah
University of Crete
C. Casadio
University of Crete
Víctor Casanova
Spanish National Research Council (CSIC)
A.J. Castro-Tirado
Spanish National Research Council (CSIC)
E. Fernández-García
Spanish National Research Council (CSIC)
M. Garcia-Comas
Spanish National Research Council (CSIC)
T.S. Grishina
Saint Petersburg State University - Spsu
P. Hakala
University of Turku
T. Hovatta
University of Turku
Y.D. Hu
Spanish National Research Council (CSIC)
C. Husillos
Instituto Geológico y Minero de España (IGME)
J. Escudero
Spanish National Research Council (CSIC)
J. Jormanainen
University of Turku
F. José Aceituno
Spanish National Research Council (CSIC)
M. Kagitani
Tohoku University
S. Kiehlmann
University of Crete
E. Kontopodis
University of Crete
E.N. Kopatskaya
Saint Petersburg State University - Spsu
P.M. Kouch
University of Turku
V. Kravtsov
University of Turku
A. Lähteenmäki
Aalto University
E.G. Larionova
Saint Petersburg State University - Spsu
E. Lindfors
University of Turku
N. Mandarakas
University of Crete
A. Marchini
University of Siena
J. R. Masiero
California Institute of Technology (Caltech)
D. Mawet
California Institute of Technology (Caltech)
W. Max-Moerbeck
University of Chile (UCH)
D.A. Morozova
Saint Petersburg State University - Spsu
I. Myserlis
Institut de Radioastronomie Millimétrique (IRAM)
K. Nilsson
University of Turku
Georgia Virginia Panopoulou
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
T. J. Pearson
California Institute of Technology (Caltech)
A. C.S. Readhead
California Institute of Technology (Caltech)
R. Reeves
University of Concepcion
S. Romanopoulos
University of Crete
T. Sakanoi
Tohoku University
Q. Salomé
University of Turku
S.S. Savchenko
Saint Petersburg State University - Spsu
R. Skalidis
California Institute of Technology (Caltech)
Alfredo Sota
Spanish National Research Council (CSIC)
I. Syrjärinne
Aalto University
S. Tinyanont
National Astronomical Research Institute of Thailand
M. Tornikoski
Aalto University
Yu V Troitskaya
Saint Petersburg State University - Spsu
I.S. Troitskiy
Saint Petersburg State University - Spsu
A.A. Vasilyev
Saint Petersburg State University - Spsu
A. Vervelaki
University of Crete
A.V. Zhovtan
Crimean Astrophysical Observatory
L.A. Antonelli
Agenzia Spaziale Italiana
M. Bachetti
Istituto nazionale di astrofisica (INAF)
L. Baldini
National Institute for Nuclear Physics
W.H. Baumgartner
National Aeronautics and Space Administration (NASA)
R. Bellazzini
National Institute for Nuclear Physics
Stefano Bianchi
Universita degli studi - Roma Tre
S.D. Bongiorno
National Aeronautics and Space Administration (NASA)
R. Bonino
National Institute for Nuclear Physics
A. Brez
National Institute for Nuclear Physics
N. Bucciantini
Arcetri Astrophysical Observatory
F. Capitanio
Istituto nazionale di astrofisica (INAF)
S. Castellano
National Institute for Nuclear Physics
E. Cavazzuti
Agenzia Spaziale Italiana
C. Chen
Universities Space Research Association
S. Ciprini
Agenzia Spaziale Italiana
E. Costa
Istituto nazionale di astrofisica (INAF)
A. De Rosa
Istituto nazionale di astrofisica (INAF)
E. Del Monte
Istituto nazionale di astrofisica (INAF)
L. Di Gesu
Agenzia Spaziale Italiana
N. Di Lalla
Kavli Institute for Particle Astrophysics and Cosmology
A. Di Marco
Istituto nazionale di astrofisica (INAF)
I. Donnarumma
Agenzia Spaziale Italiana
V. Doroshenko
University of Tübingen
M. Dovčiak
Czech Academy of Sciences
S.R. Ehlert
National Aeronautics and Space Administration (NASA)
T. Enoto
RIKEN
Y. Evangelista
Istituto nazionale di astrofisica (INAF)
S. Fabiani
Istituto nazionale di astrofisica (INAF)
R. Ferrazzoli
Istituto nazionale di astrofisica (INAF)
J.A. Garcia
California Institute of Technology (Caltech)
S. Gunji
Yamagata University
M. Gurwell
Harvard-Smithsonian Center for Astrophysics
K. Hayashida
Osaka University
J. Heyl
University of British Columbia (UBC)
W. Iwakiri
Chiba University
P. Kaaret
National Aeronautics and Space Administration (NASA)
V. Karas
Czech Academy of Sciences
G. Keating
Harvard-Smithsonian Center for Astrophysics
F. Kislat
University of New Hampshire
T. Kitaguchi
RIKEN
J.J. Kolodziejczak
National Aeronautics and Space Administration (NASA)
F. La Monaca
Istituto nazionale di astrofisica (INAF)
L. Latronico
National Institute for Nuclear Physics
S. Maldera
National Institute for Nuclear Physics
A. Manfreda
National Institute for Nuclear Physics
F. Marin
Observatoire Astronomique de Strasbourg
A. Marinucci
Agenzia Spaziale Italiana
H.L. Marshall
Massachusetts Institute of Technology (MIT)
F. Massaro
National Institute for Nuclear Physics
G. Matt
Universita degli studi - Roma Tre
I. Mitsuishi
Nagoya University
T. Mizuno
Hiroshima University
F. Muleri
Istituto nazionale di astrofisica (INAF)
C. Ng
The University of Hong Kong
S.L. O’Dell
National Aeronautics and Space Administration (NASA)
N. Omodei
Kavli Institute for Particle Astrophysics and Cosmology
C. Oppedisano
National Institute for Nuclear Physics
A. Papitto
Osservatorio Astronomico di Roma
G.G. Pavlov
Pennsylvania State University
A.L. Peirson
Kavli Institute for Particle Astrophysics and Cosmology
M. Pesce-Rollins
National Institute for Nuclear Physics
P. Petrucci
Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)
M. Pilia
Istituto nazionale di astrofisica (INAF)
A. Possenti
Istituto nazionale di astrofisica (INAF)
J. Poutanen
University of Turku
B.D. Ramsey
National Aeronautics and Space Administration (NASA)
J. Rankin
Istituto nazionale di astrofisica (INAF)
R. Rao
Harvard-Smithsonian Center for Astrophysics
A. Ratheesh
Istituto nazionale di astrofisica (INAF)
O.J. Roberts
Universities Space Research Association
R.W. Romani
Kavli Institute for Particle Astrophysics and Cosmology
C. Sgrò
National Institute for Nuclear Physics
P. Slane
Harvard-Smithsonian Center for Astrophysics
P. Soffitta
Istituto nazionale di astrofisica (INAF)
G. Spandre
National Institute for Nuclear Physics
D.A. Swartz
Universities Space Research Association
T. Tamagawa
RIKEN
R. Taverna
University of Padua
Y. Tawara
Nagoya University
A.F. Tennant
National Aeronautics and Space Administration (NASA)
N.E. Thomas
National Aeronautics and Space Administration (NASA)
Francesco Tombesi
University of Rome Tor Vergata
A. Trois
Istituto nazionale di astrofisica (INAF)
S. Tsygankov
University of Turku
R. Turolla
University of Padua
J. Vink
Anton Pannekoek Institute for Astronomy
M.C. Weisskopf
National Aeronautics and Space Administration (NASA)
K. Wu
University College London (UCL)
F. Xie
Istituto nazionale di astrofisica (INAF)
S. Zane
University College London (UCL)
Monthly Notices of the Royal Astronomical Society
00358711 (ISSN) 13652966 (eISSN)
Vol. 549 1 staf1122Subject Categories (SSIF 2025)
Astronomy, Astrophysics, and Cosmology
DOI
10.1093/mnras/staf1122