Long-term monitoring of mrk 501 for its very high energy γ emission and a flare in 2011 october

6533b7d1fe1ef96bd125cc9a

RESEARCH PRODUCT

Long-term monitoring of mrk 501 for its very high energy γ emission and a flare in 2011 october

B. Bartoli1 2 P. Bernardini3 4 X. J. Bi5 C. Bleve3 4 I. Bolognino6 7 P. Branchini8 A. Budano8 A. K. Calabrese Melcarne9 P. Camarri10 11 Z. Cao5 R. Cardarelli11 S. Catalanotti1 2 C. Cattaneo7 S. Z. Chen5 T. L. Chen12 Y. Chen5 P. Creti4 S. W. Cui13 B. Z. Dai14 G. D’al´ı Staiti15 Danzengluobu12 16 M. Dattoli17 19 18 I. De Mitri3 4 B. D’ettorre Piazzoli1 2 T. Di Girolamo1 2 X. H. Ding12 G. Di Sciascio11 C. F. Feng20 Zhaoyang Feng5 Zhenyong Feng21 F. Galeazzi8 E. Giroletti6 7 Q. B. Gou5 Y. Q. Guo5 H. H. He5 Haibing Hu12 Hongbo Hu5 Q. Huang21 M. Iacovacci1 2 R. Iuppa10 11 I. James8 22 H. Y. Jia21 Labaciren12 H. J. Li12 J. Y. Li20 X. X. Li5 G. Liguori6 7 C. Liu5 C. Q. Liu14 J. Liu14 M. Y. Liu12 H. Lu5 L. L. Ma5 X. H. Ma5 G. Mancarella3 4 22 8 G. Marsella3 4 D. Martello3 4 S. Mastroianni2 P. Montini8 22 C. C. Ning12 A. Pagliaro16 23 M. Panareo3 4 B. Panico10 11 L. Perrone3 4 P. Pistilli8 22 F. Ruggieri8 P. Salvini7 R. Santonico10 11 P. R. Shen5 X. D. Sheng5 F. Shi5 C. Stanescu8 A. Surdo4 Y. H. Tan5 P. Vallania17 18 S. Vernetto17 18 C. Vigorito18 19 B. Wang5 H. Wang5 C. Y. Wu5 H. R. Wu5 B. Xu21 L. Xue20 Q. Y. Yang14 X. C. Yang14 Z. G. Yao5 A. F. Yuan12 M. Zha5 H. M. Zhang5 Jilong Zhang5 Jianli Zhang5 L. Zhang14 P. Zhang14 X. Y. Zhang20 Y. Zhang5 J. Zhao5 Zhaxisangzhu12 Zhaxiciren12 X. X. Zhou21 F. R. Zhu21 Q. Q. Zhu5 G. Zizzi91 Dipartimento Di Fisica Dell’universita` Di Napoli “Federico Ii ” Complesso Universitario Di Monte Sant’angelo Via Cinthia I. 80126 Napoli Italy2 Istituto Nazionale Di Fisica Nucleare Sezione Di Napoli Complesso Universitario Di Monte Sant’angelo Via Cinthia I. 80126 Napoli Italy3 Dipartimento Di Matematica E. Fisica “.E. De Giorgi” Dell’universita` Del Salento Via Per Arnesano I. 73100 Lecce Italy4 Istituto Nazionale Di Fisica Nucleare Sezione Di Lecce Via Per Arnesano I. 73100 Lecce Italy5 Key Laboratory Of Particle Astrophysics Institute Of High Energy Physics Chinese Academy Of Sciences P. O. Box 918 100049 Beijing China C.h.e.n.s.z.@.i.h.e.p. A.c. Cn6 Dipartimento Di Fisica Nucleare E. Teorica Dell’universita` Di Pavia Via Bassi 6 I. 27100 Pavia Italy7 Istituto Nazionale Di Fisica Nucleare Sezione Di Pavia Via Bassi 6 I. 27100 Pavia Italy8 Istituto Nazionale Di Fisica Nucleare Sezione Di Roma Tre Via Della Vasca Navale 84 I. 00146 Roma Italy9 Istituto Nazionale Di Fisica Nucleare–cnaf Viale Berti Pichat 6/2 I. 40127 Bologna Italy10 Dipartimento Di Fisica Dell’universita` Di Roma “Tor Vergata ” Via Della Ricerca Scientifica 1 I. 00133 Roma Italy11 Istituto Nazionale Di Fisica Nucleare Sezione Di Roma Tor Vergata Via Della Ricerca Scientifica 1 I. 00133 Roma Italy12 Tibet University 850000 Lhasa Xizang China13 Hebei Normal University Shijiazhuang 050016 Hebei China14 Yunnan University 2 North Cuihu R.d.650091 Kunming Yunnan China15 Dipartimento Di Fisica E. Tecnologie Relative Universita` Degli Studi Di Palermo Viale Delle Scienze Edificio 18 I. 90128 Palermo Italy16 Istituto Nazionale Di Fisica Nucleare Sezione Di Catania Viale A. Doria 6 I. 95125 Catania Italy17 Osservatorio Astrofisico Di Torino Istituto Nazionale Di Astrofisica Corso Fiume 4 I. 10133 Torino Italy18 Istituto Nazionale Di Fisica Nucleare Sezione Di Torino Via P. Giuria 1 I. 10125 Torino Italy19 Dipartimento Di Fisica Generale Dell’universita` Di Torino Via P. Giuria 1 I. 10125 Torino Italy20 Shandong University 250100 Jinan Shandong China21 Southwest Jiaotong University 610031 Chengdu Sichuan China22 Dipartimento Di Fisica Dell’universita` “Roma Tre ” Via Della Vasca Navale 84 I. 00146 Roma Italy23 Istituto Di Astrofisica Spaziale E. Fisica Cosmica Dell’istituto Nazionale Di Astrofisica Via La Malfa 153 I. 90146 Palermo Italyreceived 2012 March 8 Accepted 2012 July 27 Published 2012 September 18 Stefano Maria Mari

subject

Active galactic nucleus active" ["galaxies]Astrophysics::High Energy Astrophysical Phenomena Flux Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics 7. Clean energy 01 natural sciences Spectral line law.invention law 0103 physical sciences Blazar 010303 astronomy & astrophysics Physics individual (Markarian 501) – galaxies: active – gamma rays: general – radiation mechanisms: non-thermal [BL Lacertae objects]" "general" ["gamma rays]010308 nuclear & particles physics BL Lacertae objects: individual (Markarian 501) – galaxies: active – gamma rays: general – radiation mechanisms: non-thermal Settore FIS/01 - Fisica Sperimentale Astronomy and Astrophysics Quasar Galaxy individual (Markarian 501)" ["BL Lacertae objects]13. Climate action Space and Planetary Science Spectral energy distribution Flare

description

"As one of the brightest active blazars in both X-ray and very high energy γ -ray bands, Mrk 501, is very useful for" "physics associated with jets from active galactic nuclei. The ARGO-YBJ experiment has monitored Mrk 501 for γ - rays above 0.3 TeV since 2007 November. The largest flare since 2005 was observed from 2011 October and lasted until about 2012 April. In this paper, a detailed analysis of this event is reported. During the brightest γ -ray flaring episodes from 2011 October 17 to November 22, an excess of the event rate over 6σ is detected by ARGO-YBJ in the direction of Mrk 501, corresponding to an increase of the γ -ray flux above 1 TeV by a factor of 6.6 ± 2.2 from its steady emission. In particular, the γ -ray flux above 8 TeV is detected with a significance better than 4σ . Based on time-dependent synchrotron self-Compton (SSC) processes, the broadband energy spectrum is interpreted as the emission from an electron energy distribution parameterized with a single power-law function with an exponential cutoff at its high-energy end. The average spectral energy distribution for the steady emission is well described by this simple one-zone SSC model. However, the detection of γ -rays above 8 TeV during the flare challenges this model due to the hardness of the spectra. Correlations between X-rays and γ -rays are also investigated."

year	journal	country	edition	language
2012-01-01

10.1088/0004-637x/758/1/2 http://hdl.handle.net/2318/124029