FERMI LARGE AREA TELESCOPE DETECTION OF EXTENDED GAMMA-RAY EMISSION FROM THE RADIO GALAXY FORNAX A

Journal article


Publication Details

Author(s): Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bellazzini R, Bissaldi E, Blandford RD, Bloom ED, Bonino R, Brandt TJ, Bregeon J, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caragiulo M, Caraveo PA, Cavazzuti E, Cecchi C, Charles E, Chekhtman A, Cheung CC, Chiaro G, Ciprini S, Cohen JM, Cohen-Tanugi J, Costanza F, Cutini S, D'Ammando F, Davis DS, De Angelis A, De Palma F, Desiante R, Digel SW, Di Lalla N, Di Mauro M, Di Venere L, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Georganopoulos M, Giglietto N, Giordano F, Giroletti M, Godfrey G, Green D, Grenier IA, Guiriec S, Hays E, Hewitt JW, Hill AB, Jogler T, Johnnesson G, Kensei S, Kuss M, Larsson S, Latronico L, Li J, Li L, Longo F, Loparco F, Lubrano P, Magill JD, Maldera S, Manfreda A, Mayer M, Mazziotta MN, Mcconville W, Mcenery JE, Michelson PF, Mitthumsiri W, Mizuno T, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Negro M, Nuss E, Ohno M, Ohsugi T, Orienti M, Orlando E, Ormes JF, Paneque D, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Schmid J, Sgro C, Simone D, Siskind EJ, Spada F, Spandre G, Spinelli P, Stawarz L, Takahashi H, Thayer JB, Thompson DJ, Torres DF, Tosti G, Troja E, Vianello G, Wood KS, Wood M, Zimmer S
Journal: Astrophysical Journal
Publisher: American Astronomical Society
Publication year: 2016
Volume: 826
Journal issue: 1
ISSN: 0004-637X


Abstract


We report the Fermi Large Area Telescope detection of extended gamma-ray emission from the lobes of the radio galaxy Fornax. A using 6.1 years of Pass. 8 data. After Centaurus. A, this is now the second example of an extended gamma-ray source attributed to a radio galaxy. Both an extended flat disk morphology and a morphology following the extended radio lobes were preferred over a point-source description, and the core contribution was constrained to be < 14% of the total gamma-ray flux. A preferred alignment of the gamma-ray elongation with the radio lobes was demonstrated by rotating the radio lobes template. We found no significant evidence for variability on similar to 0.5 year timescales. Taken together, these results strongly suggest a lobe origin for the gamma-rays. With the extended nature of the > 100 MeV gamma-ray emission established, we model the source broadband emission considering currently available total lobe radio and millimeter flux measurements, as well as X-ray detections attributed to inverse Compton (IC) emission off the cosmic microwave background (CMB). Unlike the Centaurus. A case, we find that a leptonic model involving IC scattering of CMB and extragalactic background light (EBL) photons underpredicts the gamma-ray fluxes by factors of about similar to 2-3, depending on the EBL model adopted. An additional gamma-ray spectral component is thus required, and could be due to hadronic emission arising from proton-proton collisions of cosmic rays with thermal plasma within the radio lobes.



FAU Authors / FAU Editors

Funk, Stefan Prof. Dr.
Lehrstuhl für Physik


External institutions
AlbaNova University Centre / Kungliga Tekniska Högskolan AlbaNova Universitetscentrum
Clemson University
Deutsches Elektronen-Synchrotron DESY
École Polytechnique - Université Paris-Saclay
George Mason University
Hiroshima University
Italian Space Agency / Agenzia Spaziale Italiana (ASI)
Jagiellonian University / Uniwersytet Jagielloński (UJ)
Mahidol University / มหาวิทยาลัยมหิดล
National Aeronautics and Space Administration (NASA)
National Institute for Astrophysics / Istituto Nazionale Astrofisica (INAF)
National Institute for Nuclear Physics / Istituto Nazionale di Fisica Nucleare (INFN)
NYCB Real-Time Computing, Inc.
Spanish National Research Council / Consejo Superior de Investigaciones Científicas (CSIC)
Stanford University
University of California Irvine
University of Denver
University of Geneva / Université de Genève (UNIGE)
University of Iceland (UI)
University of Maryland
University of Maryland, Baltimore County
University of Montpellier / Université Montpellier
University of North Florida (UNF)
University of Padua
University of Paris 7 - Denis Diderot / Université Paris VII Denis Diderot
University of Pisa / Università di Pisa (UniPi)
University of Udine / Università degli Studi di Udine
U.S. Naval Research Laboratory


How to cite

APA:
Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D.,... Zimmer, S. (2016). FERMI LARGE AREA TELESCOPE DETECTION OF EXTENDED GAMMA-RAY EMISSION FROM THE RADIO GALAXY FORNAX A. Astrophysical Journal, 826(1). https://dx.doi.org/10.3847/0004-637X/826/1/1

MLA:
Ackermann, M., et al. "FERMI LARGE AREA TELESCOPE DETECTION OF EXTENDED GAMMA-RAY EMISSION FROM THE RADIO GALAXY FORNAX A." Astrophysical Journal 826.1 (2016).

BibTeX: 

Last updated on 2018-06-08 at 14:40