THE 2012 FLARE OF PG 1553+113 SEEN WITH H.E.S.S. AND FERMI-LAT

Journal Article · Fri Mar 20 00:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/802/1/65· OSTI ID:22522024

Abramowski, A. ^[1]; Aharonian, F.; Benkhali, F. Ait ^[2]; Akhperjanian, A. G. ^[3]; Angüner, E. O. ^[4]; Backes, M. ^[5]; Balenderan, S. ^[6]; Balzer, A. ^[7]; Barnacka, A. ^[8]; Becherini, Y. ^[9]; Tjus, J. Becker ^[10]; Berge, D. ^[11]; Bernhard, S. ^[12]; others, and

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1. Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, D-22761 Hamburg (Germany)
2. Max-Planck-Institut für Kernphysik, P.O. Box 103980, D-69029 Heidelberg (Germany)
3. National Academy of Sciences of the Republic of Armenia, Marshall Baghramian Avenue, 24, 0019 Yerevan, Republic of Armenia (Armenia)
4. Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, D-12489 Berlin (Germany)
5. University of Namibia, Department of Physics, Private Bag 13301, Windhoek (Namibia)
6. University of Durham, Department of Physics, South Road, Durham DH1 3LE (United Kingdom)
7. GRAPPA, Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)
8. Obserwatorium Astronomiczne, Uniwersytet Jagielloński, ul. Orla 171, 30-244 Kraków (Poland)
9. Department of Physics and Electrical Engineering, Linnaeus University, SE-351 95 Växjö (Sweden)
10. Institut für Theoretische Physik, Lehrstuhl IV: Weltraum und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)
11. GRAPPA, Anton Pannekoek Institute for Astronomy and Institute of High-Energy Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)
12. Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität Innsbruck, A-6020 Innsbruck (Austria)

Very high energy (VHE, E > 100 GeV) γ-ray flaring activity of the high-frequency peaked BL Lac object PG 1553+113 has been detected by the H.E.S.S. telescopes. The flux of the source increased by a factor of 3 during the nights of 2012 April 26 and 27 with respect to the archival measurements with a hint of intra-night variability. No counterpart of this event has been detected in the Fermi-Large Area Telescope data. This pattern is consistent with VHE γ-ray flaring being caused by the injection of ultrarelativistic particles, emitting γ-rays at the highest energies. The dataset offers a unique opportunity to constrain the redshift of this source at z = 0.49 ± 0.04 using a novel method based on Bayesian statistics. The indication of intra-night variability is used to introduce a novel method to probe for a possible Lorentz invariance violation (LIV), and to set limits on the energy scale at which Quantum Gravity (QG) effects causing LIV may arise. For the subluminal case, the derived limits are E{sub QG,1} > 4.10 × 10{sup 17} GeV and E{sub QG,2} > 2.10 × 10{sup 10} GeV for linear and quadratic LIV effects, respectively.

• OSTI ID: 22522024
• Journal Information: Astrophysical Journal, Vol. 802, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BL LACERTAE OBJECTS
DISTANCE
GALAXIES
GAMMA RADIATION
GEV RANGE
LORENTZ INVARIANCE
PROBES
QUANTUM GRAVITY
RED SHIFT
RELATIVISTIC RANGE
STELLAR FLARES
TELESCOPES