Fermi meets Jansky: AGN in Radio and Gamma-Rays

248 Pages·2010·13.2 MB·English

by  Krzysztof Nalewajko

Proceedings of the
Workshop
“Fermi meets Jansky:
AGN in Radio and Gamma-Rays”
held in Bonn
June 21st-23rd 2010
Edited by
1
Tuomas Savolainen
Eduardo Ros1,2
1
Richard W. Porcas
1
J. Anton Zensus
1: Max-Planck-Institut f¨ur Radioastronomie
2: Universitat de Val`encia
Published by the Max-Planck-Institut f¨ur Radioastronomie, Bonn, Germany
c MPIfR 2010
(cid:13)
Proceedings of the Workshop: “Fermi meets Jansky: AGN in Radio and Gamma-Rays”,
held at the Max-Planck-Institut f¨ur Radioastronomie, Bonn, Germany, on 21-23 June,
2010.
Edited by: Tuomas Savolainen, Eduardo Ros, Richard W. Porcas, J. Anton Zensus.
Cover illustration: Matthias Kadler
(Collage showing gamma-ray emission observed by the Large Area Telescope (LAT) onboard NASA’s Fermi Gamma-Ray
Space Telescope in its first-flight all-sky image (Credit: NASA/DOE/International LAT Team) and associations of the
brightestpointsourceswithpowerfulparsec-scalejetsinAGNfromtheMOJAVEVeryLongBaselineArrayprogram. Image
courtesy of M. Kadler, Sternwarte Bamberg (Univ. Erlangen), the MOJAVE- and Fermi/LAT-teams.)
Cover design: Eduardo Ros
Printed by in puncto druck + medien GmbH, Bauscheidtstr. 11, Bonn, Germany.
Table of Contents
AGN in the Gamma-Ray and Radio Skies
General properties of Fermi/LAT blazars
B. Lott .................................................................................................. 1
The radio gamma-ray connection in AGNs in the era of Fermi/LAT
M. Giroletti, A. Reimer, L. Fuhrmann, V. Pavlidou, J.L. Richards, on behalf of the Fermi/LAT collaboration,
E. Angelakis .............................................................................................. 9
Identifying Fermi–LAT AGN using high-frequency radio surveys
E.K. Mahony, E.M. Sadler, T. Murphy, R.D. Ekers, P.G. Edwards, M. Massardi, on behalf of the AT20G team . 13
The γ-ray properties of radio-selected extragalactic jets
M. B¨ock, M. Kadler, G. Tosti, T.H. Burnett, C. M¨uller, R. Ojha, on behalf of the LAT collaboration,J. Wilms 17
Study of a microwave selected sample at gamma-ray energies
D. Gasparrini, E. Cavazzuti, P. Giommi, C. Pittori, S. Colafrancesco, on behaf of the Fermi/LAT collaboration . 21
Multi-band properties of superluminal AGN detected by Fermi/LAT
T.G. Arshakian, J. Leo´n-Tavares, J. Torrealba, V.H. Chavushyan ............................................ 25
Young radio sources: a radio-gamma perspective
M. Orienti, G. Migliori .................................................................................... 29
Redshift properties of MASIV sources
T.Pursimo,R.Ojha,D.L.Jauncey,J.E.J.Lovell,B.J.Rickett,J.-P.Macquart,H.E.Bignall,L.Kedziora-Chudczer,
M. Dutka, C. Senkbell, S. Shabala ......................................................................... 33
The first IRAM/PdBI polarimetric millimeter survey of AGN
S. Trippe, R. Neri, M. Krips, A. Castro-Carrizo, M. Bremer, V. Pi´etu, A.L. Fontana .......................... 37
Blazar Emission Models
Models for the spectral energy distributions and variability of blazars
M. B¨ottcher .............................................................................................. 41
Combined synchrotron and nonlinear synchrotron-self-Compton cooling of relativistic electrons
R. Schlickeiser, M. B¨ottcher, U. Menzler, M. Zacharias ..................................................... 49
Electromagnetic cascade in the vicinity of a supermassive black hole
S. Vincent, S. LeBohec ................................................................................... 53
Radio-sub-mm flares from blazars in a discontinuous jet model
J. Rachen, M. H¨aberlein, F. Reimold, T.P. Krichbaum ...................................................... 57
Hadronic γ-ray emission from extragalactic mini radio lobes
M. Kino, K. Asano ....................................................................................... 61
Radio Variability of Gamma-Ray AGN
Probing the physics of gamma-ray blazars with single-dish monitoring data
M.F. Aller, P.A. Hughes, H.D. Aller ....................................................................... 65
From EGRET to Fermi: mm-radio data and the origin of gamma-ray emission
E. Valtaoja, M. Tornikoski,J. Leo´n-Tavares, E. Nieppola, A. L¨ahteenm¨aki, J. Tammi, T. Hovatta ............. 73
i
The relation between the radio and gamma-ray emission in blazars from 15 GHz monitoring with the
OVRO 40-m Telescope and Fermi observations
W. Max-Moerbeck, J.L. Richards, V. Pavlidou, T.J. Pearson, A.C.S. Readhead, M.A. Stevenson, O. King,
R. Reeves, K. Karkare, E. Angelakis, L. Fuhrmann, J.A. Zensus, S.E. Healey, R.W. Romani, M.S. Shaw ....... 77
The F-GAMMA program: multi-wavelength AGN studies in the Fermi-GST era
E. Angelakis L. Fuhrmann I. Nestoras J.A. Zensus N. Marchili V. Pavlidou T.P. Krichbaum ................... 81
Studyof a completesample of radio-brightAGNs: propertiesof gamma-raybright and gamma-ray faint
radio sources in the first year of Fermi operations
M. Tornikoski,E. Nieppola, E. Valtaoja, J. Leo´n-Tavares, A. L¨ahteenm¨aki ................................... 85
Correlations between the Fermi/LATgamma-ray and 37 GHz radio properties of AGN averaged over 11
months
E. Nieppola, M. Tornikoski,E. Valtaoja, J. Leo´n-Tavares, T. Hovatta, A. L¨ahteenm¨aki, J. Tammi ............. 89
The connection between γ-ray emission and radio flares in Fermi/LAT blazars
J. Leo´n-Tavares, E. Valtaoja, M. Tornikoski,A. , L¨ahteenm¨aki, E. Nieppola .................................. 93
Shock-shock interaction in the jet of CTA102
C.M.Fromm,E.Ros,T.Savolainen,A.P.Lobanov,M.Perucho,J.A.Zensus,M.F.Aller,H.D.Aller,M.A.Gurwell,
A. L¨ahteenm¨aki .......................................................................................... 97
Multi-Frequency Studies
Cross-analyzing radio and γ-Ray time series data: Fermi marries Jansky
J.D. Scargle .............................................................................................. 101
Modeling AGN spectral energy distributions with leptonic models
J.D. Finke for the Fermi-LAT Collaboration ................................................................ 109
Localization of the gamma-ray emission site using multi-waveband data and mm-VLBI
S.G. Jorstad, A.P. Marscher, P.S. Smith, V.M. Larionov, I. Agudo ........................................... 115
Recent multi-wavelength campaigns in the Fermi-GST era
L. Fuhrmann ............................................................................................. 121
Monitoring of γ-ray blazars with AGILE
F. D’Ammando, on behalf of the AGILE team .............................................................. 127
Long-term multi-wavelength monitoring of the blazar 3C 454.3
S. Vercellone, on behaf of the AGILE AGN Working Group .................................................. 135
The broadband spectral energy distribution of the MOJAVE sample
C.-S. Chang, E. Ros, M. Kadler, M.F. Aller, H.D. Aller, E. Angelakis, L. Fuhrmann, I. Nestoras, H. Ungerechts 139
The multi–spectral–range behavior of OJ 287 in 2005–2010
I. Agudo, S.G. Jorstad, A.P. Marscher, V.M. Larionov, J.L. G´omez, H. Wiesemeyer, C. Thum, M.A Gurwell,
J. Heidt, F.D. D’Arcangelo ................................................................................ 143
The unusual radio & gamma-ray Properties of the quasar 4C+55.17
W. McConville, L. Stawarz, L. Ostorero, R. Moderski, C.C. Cheung ......................................... 147
ii
VLBI Observations of Gamma-Ray AGN
Physical properties of the blazar jets from VLBI observations
A.P. Lobanov ............................................................................................ 151
Parsec-scale jet properties of Fermi-detected AGN
M.L. Lister ............................................................................................... 159
Radio-gamma time delay in the cores of AGN
A.B. Pushkarev, Y.Y. Kovalev, M.L. Lister ................................................................. 163
Constraints on the gamma-ray emitting region in blazars from multifrequency VLBI measurements
K.V. Sokolovsky, Y.Y. Kovalev, A.P. Lobanov, J.D. Finke, T. Savolainen, A.B. Pushkarev, M. Kadler,
F.K. Schinzel, V.H. Chavushyan, L. Carrasco, A. Carrami˜nana, M.A. Gurwell ................................ 167
Rapid variability of gamma-ray emission from sites near the 43GHz cores of blazar jets
A.P. Marscher, S.G. Jorstad ............................................................................... 171
Radio flaring activity of 3C 345 and its connection to γ-ray emission
F.K. Schinzel, A.P. Lobanov, S.G. Jorstad, A.P. Marscher, G.B. Taylor, J.A. Zensus .......................... 175
The TANAMI program
R. Ojha, M. Kadler, M. B¨ock, F. Hungwe, C. M¨uller, J. Wilms, E. Ros, the TANAMI team ................... 179
A new sample of faint blazars
F. Mantovani, M. Bondi, K.-H. Mack ...................................................................... 183
The jet in M87 from e-EVN observations
G. Giovannini, C. Casadio, M. Giroletti, M. Beilicke, A. Cesarini, H. Krawczynski ............................. 187
Revealing the jets of the faintest BL Lacs
M.Giroletti,E.Masaro,M.Kadler,G.Tosti,G.B.Taylor,onbehalfoftheFermi/LATcollaboration,G.Giovannini,
C. Casadio, E. Liuzzo, S. Tamburri ........................................................................ 191
Gamma-ray duty cycle in the bright parsec-scale AGN jets
T. Hovatta, M.L. Lister, Y.Y. Kovalev, A.B. Pushkarev ..................................................... 195
VLBI monitoring of the bright gamma-ray blazar PKS0537-441
F. Hungwe, R. Ojha, M. Kadler, R. Booth, J. Blanchard, J.E.J. Lovell, C. M¨uller, M. B¨ock, the TANAMI team 199
Superluminal motion in AGNs and GRBs
Z.-B. Zhang .............................................................................................. 203
Jet Physics
M87 and the dynamics and microphysics inside the blazar zone
P. Hardee ................................................................................................ 207
Resolving the Doppler-factor crisis in AGNs: non-steady magnetized outflows
M. Lyutikov, M.L. Lister .................................................................................. 213
Gamma-ray emission from mini-jets
K. Nalewajko ............................................................................................. 217
iii
Non-Blazar Gamma-Ray AGN
VLBI monitoring of 3C 84 in gamma-ray active phase
H. Nagai, K. Suzuki, K. Asada, S. Kameno, A. Doi, M. Inoue, U. Bach ...................................... 221
Centaurus A as a cosmic ray accelerator
R.J. Protheroe ........................................................................................... 225
Subparsec scale imaging of Centaurus A
C. M¨uller, M. Kadler, R. Ojha, M. B¨ock, C.M. Fromm, E. Ros, R.E. Rothschild, J. Wilms .................... 229
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Preface
This volume contains the papers to be presented at the Workshop “Fermi meets Jansky: AGN
in Radio and Gamma-Rays”, held at the Max-Planck-Institut f¨ur Radioastronomie in Bonn on
June 21–23 2010. Around 70 scientists from around the world will come together to discuss
the recent rapid advances in the field of active galactic nuclei (AGN) research, triggered by the
first results from the Fermi Gamma-ray Space Telescope. The number of scientists interested
in the topic was significantly greater than the number which could be accommodated. We offer
our apologies to all those who therefore could not be admitted to the workshop.
Itisnotknownwhether EnricoFermi, oneoftheeminentphysicistsofthe20thcentury, andKarl
Jansky, the father of radio astronomy, ever met. Fermi emigrated to the United States 12 years
before Jansky’s death, thus creating a chance for an encounter, but at this point Jansky was not
pursuing astronomical research any more. Most likely the two did not have professional contact
during their lifetimes, but today their scientific legacies, particle physics and radio astronomy,
are tightly inter-twined in the field of high energy astrophysics. Radio synchrotron radiation is a
tell-tale sign of highly energetic particles in our Universe, particles which may have gained their
energy via acceleration processes named after Fermi.
Thehighlyrelativistic particlesfoundinAGNs arenotonlyradio-emitters, buttheyalsogenerate
copious amounts of radiationthroughout the whole electromagnetic spectrum up to TeV γ-rays.
Since the EGRET instrument on-board the Compton Gamma-ray Observatory opened up the
γ-ray sky, the origin of the prominent high energy radiation from AGNs has been one of the
major open questions in modern astrophysics. It is fair to say that this discovery strongly
influenced the field of AGN studies.
Despite the seminal discoveries made by EGRET, its sensitivity was not great and the resulting
γ-ray light curves were too poorly sampled to be able to decisively select among the various
models that were proposed to explain the AGN γ-ray emission, thus creating a long-lasting
controversy amongstthe proponents of different hypotheses. Now, two decades after the launch
of CGRO, we are at a turning point. The MeV-GeV γ-ray sky is currently being observed with
unprecedented sensitivity by two new satellites, AGILE and Fermi. At the same time the latest
generation of ground-based atmospheric imaging Cherenkov telescopes is detecting new TeV-
emittingAGNataneverincreasingrate. Inparticular,Fermihasrevolutionisedγ-raystudiesdue
to its high sensitivity, wide energy range, large field-of-view, and an observing mode that allows
continuous all-sky monitoring. Equipped with these state-of-the-art instruments, astrophysicists
are now able to draw a comprehensive picture of the γ-ray emitting AGN population.
The emission from the high-energy particles in AGN is, however, a broadband phenomenon,
and it has been clear for a while that, in order to understand the physics behind the high
v
energy emission, a multi-wavelength approach is necessary. Since the EGRET era there have
been indications that the γ-ray brightness of AGN is linked to their radio–mm-wavelength
properties, and the first results from joint Fermi γ-ray and radio studies have now confirmed
this. The connection is there, and one big question now is how intimate it is. Are the radio–
mm-wavelength properties andtheγ-raybrightness correlated justbecausethe radiationatboth
extremes of the spectrum is emitted from a relativistic jet? Or are the two emission processes
more tightly knit with a possibly co-spatial production of both? The goal of the “Fermi meets
Jansky” workshop is to bring together experts from both the radio and γ-ray communities to
discuss our understanding of high energy physics in AGN. One of the central themes will be the
location of the γ-ray emitting region. How close is it to the central black hole? We hope that
the workshop serves to converge the views about this and other open questions or at least helps
to outline what observations are needed to settle the long-standing debates.
Tomaximisetheusefulness ofthese proceedingsitwasdecided thatthey bepublished beforethe
workshop, so that the proceedings can serve as a reference during the discussions at the meeting
and that they may help foster further interaction among scientists soon after the meeting. We
thank the authors for their co-operation in delivering publication-ready electronic manuscripts
and for meeting the strict deadlines. It is highly gratifying that—except for a handful—almost
all of the 55 presentations could be included in this book.
The editorial work was limited to copy editing and to some amount of language editing in order
to improve the readability of the book. No refereeing regarding the scientific content of the
contributions was performed. The editors take responsibility for any errors generated in the
papers by their editorial work.
Besides the authors, many individuals have contributed to the preparation of the meeting and
the proceedings. The organisers are indebted to the members of the scientific organising com-
mittee, who did a terrific job in creating the scientific program of the meeting. In addition to
many members of the MPIfR staff, we especially wish to thank E. Fingas, C.M. Fromm, H.
Kalisch, B. Naunheim, F.K. Schinzel, and H. Sturm for the local organisation, and M. Kadler
(Sternwarte Bamberg) for providing the illustration of the book cover. Financial support for the
Symposium came from the 7th Framework Programme of the European Commission, Advanced
Radio Astronomy in Europe, grant agreement no.: 227290, and from the Max-Planck-Institut
f¨ur Radioastronomie.
th
In Bonn, on the 11 of June 2010,
Tuomas Savolainen
Eduardo Ros
Richard W. Porcas
J. Anton Zensus
vi
List of Participants
Iva´n Agudo ChristianM. Fromm YuriY. Kovalev
Boston University MPI fu¨r Radioastronomie AstroSpaceCenterofLebedevPhysical
[email protected] [email protected] Institute
[email protected]
HughD. Aller Lars Fuhrmann
ThomasP. Krichbaum
University of Michigan MPI fu¨r Radioastronomie
[email protected] [email protected] MPI fu¨r Radioastronomie
[email protected]
MargoF. Aller KrisztinaEva Gabanyi
Anne La¨hteenma¨ki
University of Michigan Hungarian Academ Res. Groupy of Sci-
[email protected] ences, Phys. Geodesy and Geodynamics Aalto University Mets¨ahovi Radio Ob-
Res. Group servatory
Emmanouil Angelakis
[email protected] [email protected]
MPI fu¨r Radioastronomie
Dario Gasparrini Jonathan Leo´n-Tavares
[email protected]
Agenzia Spaziale Italiana Aalto University Mets¨ahovi Radio Ob-
TigranG. Arshakian
[email protected] servatory
MPI fu¨r Radioastronomie
[email protected]
Gabriele Giovannini
[email protected]
MatthewL. Lister
Astronomy Dept.- Bologna University
Peter Biermann
[email protected] PurdueUniversity
MPI fu¨r Radioastronomie
[email protected]
Marcello Giroletti
[email protected]
AndreiP. Lobanov
INAF Istituto di Radioastronomia
Roger Blandford
[email protected] MPI fu¨r Radioastronomie
Stanford University
[email protected]
Philip Hardee
[email protected]
Benoit Lott
University of Alabama
Moritz Bo¨ck
[email protected] CENBG/IN2P3/CNRS
Dr. Remeis-Observatory and ECAP,
[email protected]
Talvikki Hovatta
Bamberg
Maxim Lyutikov
[email protected] PurdueUniversity
[email protected] PurdueUniversity
Markus Bo¨ttcher
[email protected]
Faith Hungwe
Ohio University
Elizabeth Mahony
[email protected] HartRAO
[email protected] TheUniversity of Sydney
Silke Britzen
[email protected]
SvetlanaJ. Jorstad
MPI fu¨r Radioastronomie
Franco Mantovani
[email protected] Boston University
[email protected] Istituto diRadioastronomia - INAF
Chin-Shin Chang
[email protected]
Matthias Kadler
MPI fu¨r Radioastronomie
AlanP. Marscher
[email protected] Dr. Remeis Sternwarte, Bamberg
[email protected] Boston University
ChiC. Cheung
[email protected]
KennethI. Kellermann
Naval Research Laboratory
Maria Massi
[email protected] National Radio Astronomy Observatory
[email protected] MPI fu¨r Radioastronomie
Filippo D’Ammando
[email protected]
Motoki Kino
INAF-IASF Palermo
Walter Max-Moerbeck
[email protected] National Astronomical Observatory of
Japan California Instituteof Technology
Justin Finke
[email protected] [email protected]
Naval Research Laboratory
[email protected]
vii
William McConville Tapio Pursimo Merja Tornikoski
Univ. of Maryland Nordic OpticalTelescope Aalto University Mets¨ahovi Radio Ob-
[email protected] [email protected] servatory
[email protected]
Cornelia Mu¨ller AlexanderB. Pushkarev
Gino Tosti
Dr. Remeis-Observatory and ECAP, MPI fu¨r Radioastronomie
Bamberg [email protected] University of Perugia andINFN Perugia
[email protected] [email protected]
Jo¨rg Rachen
Hiroshi Nagai Sascha Trippe
MPI for Astrophysics
National Astronomical Observatory of [email protected] IRAM Grenoble
Japan [email protected]
AnthonyC.S. Readhead
[email protected]
Tasso Tzioumis
California Institute of Technology
Krzysztof Nalewajko
[email protected] CSIRO,ATNF
Nicolaus Copernicus Astronomical Cen- [email protected]
Patrizia Romano
ter
Esko Valtaoja
INAF/IASF Palermo
[email protected]
[email protected] Tuorla Observatory, University of Turku
Elina Nieppola
[email protected]
Eduardo Ros
Mets¨ahovi RadioObservatory
Stefano Vercellone
Univ. Valencia and MPI fu¨r Radioas-
[email protected]
tronomie INAF/IASF Palermo
Roopesh Ojha
[email protected] [email protected]
NVI / USNO
Tuomas Savolainen Stephane Vincent
[email protected]
MPI fu¨r Radioastronomie University of Utah
Monica Orienti
[email protected] [email protected]
INAF - Bologna
JeffreyD. Scargle Jo¨rn Wilms
[email protected]
NASA Ames Research Center Dr. Remeis-Observatory and ECAP,
TimothyJ. Pearson
[email protected] Bamberg
California Instituteof Technology [email protected]
FrankK. Schinzel
[email protected]
Mohammad Zamaninasab
MPI fu¨r Radioastronomie
RichardW. Porcas
[email protected] MPI fu¨r Radioastronomie
MPI fu¨r Radioastronomie [email protected]
Reinhard Schlickeiser
[email protected]
J.Anton Zensus
Ruhr-University Bochum
Ray Protheroe
[email protected] MPI fu¨r Radioastronomie
University of Adelaide [email protected]
Kirill Sokolovsky
[email protected]
Zhibin Zhang
MPI fu¨r Radioastronomie
[email protected] Guizhou University
[email protected]
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