Simultaneous multiwavelength observations of the second exceptional γ-ray flare of PKS2155-304 in July 2006

被引：102

作者：

Aharonian, F. ^{[1
,13
]}

Akhperjanian, A. G. ^{[2
]}

Anton, G. ^{[16
]}

de Almeida, U. Barres ^{[8
]}

Bazer-Bachi, A. R. ^{[3
]}

Becherini, Y. ^{[12
]}

Behera, B. ^{[14
]}

Benbow, W. ^{[1
]}

Bernloehr, K. ^{[1
,5
]}

Boisson, C.

Bochow, A. ^{[1
]}

Borrel, V. ^{[3
]}

Brion, E. ^{[7
]}

Brucker, J. ^{[16
]}

Brun, P. ^{[7
]}

Buehler, R. ^{[1
]}

Bulik, T. ^{[24
]}

Buesching, I. ^{[9
]}

Boutelier, T. ^{[17
]}

Chadwick, P. M. ^{[8
]}

Charbonnier, A. ^{[19
]}

Chaves, R. C. G. ^{[1
]}

Cheesebrough, A. ^{[8
]}

Chounet, L. -M. ^{[10
]}

Clapson, A. C. ^{[1
]}

Coignet, G. ^{[11
]}

Costamante, L. ^{[1
,30
,31
]}

Dalton, M. ^{[5
]}

Daniel, M. K. ^{[8
]}

Davids, I. D. ^{[9
,22
]}

Degrange, B. ^{[10
]}

Deil, C. ^{[1
]}

Dickinson, H. J. ^{[8
]}

Djannati-Atai, A. ^{[12
]}

Domainko, W. ^{[1
]}

Drury, L. O'C. ^{[13
]}

Dubois, F. ^{[11
]}

Dubus, G. ^{[17
]}

Dyks, J. ^{[24
]}

Dyrda, M. ^{[28
]}

Egberts, K. ^{[1
]}

Emmanoulopoulos, D. ^{[14
]}

Espigat, P. ^{[12
]}

Farnier, C. ^{[15
]}

Feinstein, F. ^{[15
]}

Fiasson, A. ^{[15
]}

Foerster, A. ^{[1
]}

Fontaine, G. ^{[10
]}

Fuessling, M. ^{[5
]}

Gabici, S. ^{[13
]}

机构：

[1] Max Planck Inst Kernphys, D-69029 Heidelberg, Germany

[2] Yerevan Phys Inst, Yerevan 375036, Armenia

[3] UPS, CNRS, Ctr Etud Spatiale Rayonnements, F-31029 Toulouse 4, France

[4] Univ Hamburg, Inst Expt Phys, D-22761 Hamburg, Germany

[5] Humboldt Univ, Inst Phys, D-12489 Berlin, Germany

[6] Univ Paris Diderot, CNRS, Observ Paris, LUTH, F-92190 Meudon, France

[7] CE Saclay, CEA, IRFU, DSM, F-91191 Gif Sur Yvette, France

[8] Univ Durham, Dept Phys, Durham DH1 3LE, England

[9] North West Univ, Unit Space Phys, ZA-2520 Potchefstroom, South Africa

[10] Ecole Polytech, Lab Leprince Ringuet, F-91128 Palaiseau, France

[11] CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France

[12] Univ Paris 07, CNRS, UMR 7164, CEA,Observ Paris, F-75205 Paris 13, France

[13] Dublin Inst Adv Studies, Dublin 2, Ireland

[14] Heidelberg Univ, D-69117 Heidelberg, Germany

[15] Univ Montpellier 2, CNRS, IN2P3, Lab Phys Theor & Astroparticules, F-34095 Montpellier 5, France

[16] Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany

[17] Univ Grenoble 1, CNRS, INSU, Lab Astrophys Grenoble, F-38041 Grenoble 9, France

[18] Univ Tubingen, Inst Astron & Astrophys, D-72076 Tubingen, Germany

[19] Univ Paris 07, Univ Paris 06, LPNHE, CNRS,IN2P3, F-75252 Paris 5, France

[20] Charles Univ Prague, Fac Math & Phys, Inst Particle & Nucl Phys, Prague 18000, Czech Republic

[21] Ruhr Univ Bochum, Lehrstuhl Weltraum & Astrophys 4, Inst Theoret Phys, D-44780 Bochum, Germany

[22] Univ Namibia, Windhoek, Namibia

[23] Uniwersytet Jagiellonski, Astron Observ, PL-30244 Warsaw, Poland

[24] Nicolaus Copernicus Astron Ctr, PL-00716 Warsaw, Poland

[25] Univ Leeds, Sch Phys & Astron, Leeds LS2 9JT, W Yorkshire, England

[26] Univ Adelaide, Sch Chem & Phys, Adelaide, SA 5005, Australia

[27] Nicholas Copernicus Univ, Torun Ctr Astron, PL-87100 Torun, Poland

[28] PAN, Inst Fiz Jadrowej, PL-31342 Krakow, Poland

[29] CBA Pretoria, Bronberg Observ, ZA-0056 Tiegerpoort, South Africa

[30] Stanford Univ, WW Hansen Expt Phys Lab, Stanford, CA 94305 USA

[31] Kavli Inst Particle Astrophys & Cosmol, Stanford, CA 94305 USA

来源：

ASTRONOMY & ASTROPHYSICS | 2009年 / 502卷 / 03期

基金：

新加坡国家研究基金会; 美国国家航空航天局; 英国科学技术设施理事会;

关键词：

galaxies: active; galaxies: BL Lacertae objects: individual: PKS 2155-304; gamma rays: observations; X-rays: galaxies; BL-LAC OBJECTS; EXTRAGALACTIC BACKGROUND LIGHT; TEVBL LACERTAE OBJECTS; ACTIVE GALACTIC NUCLEI; LOG-PARABOLIC SPECTRA; SIMULTANEOUS X-RAY; PKS; 2155-304; PARTICLE-ACCELERATION; BLAZAR SEQUENCE; XMM-NEWTON;

D O I：

10.1051/0004-6361/200912128

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Aims. The X-ray-TeV connection and the evolution of the emitting particle population is studied in high-energy peaked BL Lac objects, by obtaining spectral information in both bands on sub-hour timescales. Methods. Simultaneous observations with HESS, Chandra and the Bronberg optical observatory were performed on the BL Lac object PKS 2155-304 in the night of July 29-30 2006, when the source underwent a major gamma-ray outburst during its high-activity state of Summer 2006. This event took place about 44 h after the other major outburst of the night of July 27-28, which is known for its ultrafast variability. An unprecedented 6 to 8 h of simultaneous, uninterrupted coverage was achieved, with spectra and light curves measured down to 7 and 2 min timescales, respectively. Results. The source exhibited one major flare along the night, at high energies. The gamma-ray flux reached a maximum of similar to 11 times the Crab flux (>400 GeV), with rise/decay timescales of similar to 1 h, plus a few smaller-amplitude flares superimposed on the decaying phase. The emission in the X-ray and VHE gamma-ray bands is strongly correlated, with no evidence of lags. The spectra also evolve with similar patterns, and are always soft ( photon index G > 2), indicating no strong shift of the peaks in the spectral energy distribution towards higher energies. Only at the flare maximum is there evidence that the gamma-ray peak is inside the observed passband, at similar to 400-600 GeV. The VHE spectrum shows a curvature that is variable with time and stronger at higher fluxes. The huge VHE variations (similar to 22x) are only accompanied by small-amplitude X-ray and optical variations (factor 2 and 15% respectively). The source has shown for the first time in a high-energy peaked BL Lac object a large Compton dominance (L-C/L-S similar to 10) - rapidly evolving - and a cubic relation between VHE and X-ray flux variations, during a decaying phase. These results challenge the common scenarios for the TeV-blazar emission.

引用

页码：749 / 770

页数：22

共 103 条

[21] Bertone E, 2000, ASTRON ASTROPHYS, V356, P1
[22] A multiwavelength view of the TeV blazar markarian 421:: Correlated variability, flaring, and spectral evolution
Blazejowski, MB
Blaylock, G
Bond, IH
Bradbury, SM
Buckley, JH
Carter-Lewis, DA
Celik, O
Cogan, P
Cui, W
Daniel, M
Duke, C
Falcone, A
Fegan, DJ
Fegan, SJ
Finley, JP
Fortson, L
Gammell, S
Gibbs, K
Gillanders, GG
Grube, J
Gutierrez, K
Hall, J
Hanna, D
Holder, J
Horan, D
Humensky, B
Kenny, G
Kertzman, M
Kieda, D
Kildea, J
Knapp, J
Kosack, K
Krawczynski, H
Krennrich, F
Lang, M
LeBohec, S
Linton, E
Evans, JL
Maier, G
Mendoza, D
Milovanovic, A
Moriarty, P
Nagai, TN
Ong, RA
Mooney, BP
Quinn, J
Quinn, M
Ragan, K
Reynolds, PT
Rebillot, P
[J]. ASTROPHYSICAL JOURNAL, 2005, 630 (01) : 130 - 141
[23] An analysis of the synchrotron self-compton model for the multi-wave band spectra of blazars
Bloom, SD
Marscher, AP
[J]. ASTROPHYSICAL JOURNAL, 1996, 461 (02) : 657 - 663
[24] BOUTELIER T, 2008, MNRAS, pL102
[25] THE OPTICAL VARIABILITY OF PKS-2155-304
CARINI, MT
MILLER, HR
[J]. ASTROPHYSICAL JOURNAL, 1992, 385 (01) : 146 - 150
[26] Spectral evolution of PKS 2155-304 observed with BeppoSAX during an active gamma-ray phase
Chiappetti, L
Maraschi, L
Tavecchio, F
Celotti, A
Fossati, G
Ghisellini, G
Giommi, P
Pian, E
Tagliaferri, G
Treves, A
Urry, CM
Zhang, YH
[J]. ASTROPHYSICAL JOURNAL, 1999, 521 (02) : 552 - 560
[27] Simultaneous X-ray and gamma-ray observations of TeV blazars: Testing synchro-compton emission models and probing the infrared extragalactic background
Coppi, PS
Aharonian, FA
[J]. ASTROPHYSICAL JOURNAL, 1999, 521 (01) : L33 - L36
[28] Costamante L, 2007, AIP CONF PROC, V921, P157
[29] Extreme synchrotron BL Lac objects - Stretching the blazar sequence
Costamante, L
Ghisellini, G
Giommi, P
Tagliaferri, G
Celotti, A
Chiaberge, M
Fossati, G
Maraschi, L
Tavecchio, F
Treves, A
Wolter, A
[J]. ASTRONOMY & ASTROPHYSICS, 2001, 371 (02) : 512 - 526
[30] MODEL FOR THE HIGH-ENERGY EMISSION FROM BLAZARS
DERMER, CD
SCHLICKEISER, R
[J]. ASTROPHYSICAL JOURNAL, 1993, 416 (02) : 458 - 484

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