H.E.S.S. discovery of very high energy γ -ray emission from PKS 0625-354

H.E.S.S. Collaboration

doi:10.1093/mnras/sty439

H.E.S.S. discovery of very high energy γ -ray emission from PKS 0625-354

H.E.S.S. Collaboration

Research output: Contribution to journal › Article › peer-review

25 Scopus citations

Abstract

PKS 0625-354 (z = 0.055) was observed with the four High Energy Stereoscopic System (H.E.S.S.) telescopes in 2012 during 5.5 h. The source was detected above an energy threshold of 200 GeV at a significance level of 6.1σ. No significant variability is found in these observations. The source is well described with a power-law spectrum with photon index G = 2.84 ± 0.50_stat ± 0.10_syst and normalization (at E₀ = 1.0 TeV) N₀(E₀)=(0.58±0.22_stat ±0.12_syst)×10^-12 TeV^-1 cm-2 s^-1. Multiwavelength data collected with Fermi-LAT, Swift-XRT, Swift-UVOT, ATOMand WISE are also analysed. Significant variability is observed only in the Fermi-LAT γ -ray and Swift-XRT X-ray energy bands. Having a good multiwavelength coverage from radio to very high energy, we performed a broad-band modelling from two types of emission scenarios. The results from a one zone lepto-hadronic and a multizone leptonic models are compared and discussed. On the grounds of energetics, our analysis favours a leptonic multizone model. Models associated to the X-ray variability constraint support previous results, suggesting a BL Lac nature of PKS 0625-354 with, however, a large-scale jet structure typical of a radio galaxy.

Original language	English
Pages (from-to)	4187-4198
Number of pages	12
Journal	Monthly Notices of the Royal Astronomical Society
Volume	476
Issue number	3
DOIs	https://doi.org/10.1093/mnras/sty439
State	Published - 21 May 2018
Externally published	Yes

Keywords

Galaxies: active
Galaxies: individual: PKS 0625-354
Galaxies: jets
Gamma-rays: galaxies
Radiation mechanisms: non-thermal

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

Access to Document

10.1093/mnras/sty439

Cite this

@article{c2a56818d0754ddea5b7308daebffc84,

title = "H.E.S.S. discovery of very high energy γ -ray emission from PKS 0625-354",

abstract = "PKS 0625-354 (z = 0.055) was observed with the four High Energy Stereoscopic System (H.E.S.S.) telescopes in 2012 during 5.5 h. The source was detected above an energy threshold of 200 GeV at a significance level of 6.1σ. No significant variability is found in these observations. The source is well described with a power-law spectrum with photon index G = 2.84 ± 0.50stat ± 0.10syst and normalization (at E0 = 1.0 TeV) N0(E0)=(0.58±0.22stat ±0.12syst)×10-12 TeV-1 cm-2 s-1. Multiwavelength data collected with Fermi-LAT, Swift-XRT, Swift-UVOT, ATOMand WISE are also analysed. Significant variability is observed only in the Fermi-LAT γ -ray and Swift-XRT X-ray energy bands. Having a good multiwavelength coverage from radio to very high energy, we performed a broad-band modelling from two types of emission scenarios. The results from a one zone lepto-hadronic and a multizone leptonic models are compared and discussed. On the grounds of energetics, our analysis favours a leptonic multizone model. Models associated to the X-ray variability constraint support previous results, suggesting a BL Lac nature of PKS 0625-354 with, however, a large-scale jet structure typical of a radio galaxy.",

keywords = "Galaxies: active, Galaxies: individual: PKS 0625-354, Galaxies: jets, Gamma-rays: galaxies, Radiation mechanisms: non-thermal",

author = "{H.E.S.S. Collaboration} and H. Abdalla and A. Abramowski and F. Aharonian and {Ait Benkhali}, F. and Akhperjanian, {A. G.} and T. Andersson and Ang{\"u}ner, {E. O.} and M. Arrieta and P. Aubert and M. Backes and A. Balzer and M. Barnard and Y. Becherini and {Becker Tjus}, J. and D. Berge and S. Bernhard and K. Bernl{\"o}hr and R. Blackwell and M. B{\"o}ttcher and C. Boisson and J. Bolmont and P. Bordas and J. Bregeon and F. Brun and P. Brun and M. Bryan and T. Bulik and M. Capasso and J. Carr and S. Casanova and M. Cerruti and N. Chakraborty and R. Chalme-Calvet and Chaves, {R. C.G.} and A. Chen and J. Chevalier and M. Chr{\'e}tien and S. Colafrancesco and G. Cologna and B. Condon and J. Conrad and Y. Cui and Davids, {I. D.} and J. Decock and B. Degrange and C. Deil and J. Devin and P. deWilt and L. Dirson and I. Shilon",

note = "Publisher Copyright: {\textcopyright} 2018 The Author(s).",

year = "2018",

month = may,

day = "21",

doi = "10.1093/mnras/sty439",

language = "English",

volume = "476",

pages = "4187--4198",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

publisher = "Oxford University Press",

number = "3",

}

TY - JOUR

T1 - H.E.S.S. discovery of very high energy γ -ray emission from PKS 0625-354

AU - H.E.S.S. Collaboration

AU - Abdalla, H.

AU - Abramowski, A.

AU - Aharonian, F.

AU - Ait Benkhali, F.

AU - Akhperjanian, A. G.

AU - Andersson, T.

AU - Angüner, E. O.

AU - Arrieta, M.

AU - Aubert, P.

AU - Backes, M.

AU - Balzer, A.

AU - Barnard, M.

AU - Becherini, Y.

AU - Becker Tjus, J.

AU - Berge, D.

AU - Bernhard, S.

AU - Bernlöhr, K.

AU - Blackwell, R.

AU - Böttcher, M.

AU - Boisson, C.

AU - Bolmont, J.

AU - Bordas, P.

AU - Bregeon, J.

AU - Brun, F.

AU - Brun, P.

AU - Bryan, M.

AU - Bulik, T.

AU - Capasso, M.

AU - Carr, J.

AU - Casanova, S.

AU - Cerruti, M.

AU - Chakraborty, N.

AU - Chalme-Calvet, R.

AU - Chaves, R. C.G.

AU - Chen, A.

AU - Chevalier, J.

AU - Chrétien, M.

AU - Colafrancesco, S.

AU - Cologna, G.

AU - Condon, B.

AU - Conrad, J.

AU - Cui, Y.

AU - Davids, I. D.

AU - Decock, J.

AU - Degrange, B.

AU - Deil, C.

AU - Devin, J.

AU - deWilt, P.

AU - Dirson, L.

AU - Shilon, I.

PY - 2018/5/21

Y1 - 2018/5/21

N2 - PKS 0625-354 (z = 0.055) was observed with the four High Energy Stereoscopic System (H.E.S.S.) telescopes in 2012 during 5.5 h. The source was detected above an energy threshold of 200 GeV at a significance level of 6.1σ. No significant variability is found in these observations. The source is well described with a power-law spectrum with photon index G = 2.84 ± 0.50stat ± 0.10syst and normalization (at E0 = 1.0 TeV) N0(E0)=(0.58±0.22stat ±0.12syst)×10-12 TeV-1 cm-2 s-1. Multiwavelength data collected with Fermi-LAT, Swift-XRT, Swift-UVOT, ATOMand WISE are also analysed. Significant variability is observed only in the Fermi-LAT γ -ray and Swift-XRT X-ray energy bands. Having a good multiwavelength coverage from radio to very high energy, we performed a broad-band modelling from two types of emission scenarios. The results from a one zone lepto-hadronic and a multizone leptonic models are compared and discussed. On the grounds of energetics, our analysis favours a leptonic multizone model. Models associated to the X-ray variability constraint support previous results, suggesting a BL Lac nature of PKS 0625-354 with, however, a large-scale jet structure typical of a radio galaxy.

AB - PKS 0625-354 (z = 0.055) was observed with the four High Energy Stereoscopic System (H.E.S.S.) telescopes in 2012 during 5.5 h. The source was detected above an energy threshold of 200 GeV at a significance level of 6.1σ. No significant variability is found in these observations. The source is well described with a power-law spectrum with photon index G = 2.84 ± 0.50stat ± 0.10syst and normalization (at E0 = 1.0 TeV) N0(E0)=(0.58±0.22stat ±0.12syst)×10-12 TeV-1 cm-2 s-1. Multiwavelength data collected with Fermi-LAT, Swift-XRT, Swift-UVOT, ATOMand WISE are also analysed. Significant variability is observed only in the Fermi-LAT γ -ray and Swift-XRT X-ray energy bands. Having a good multiwavelength coverage from radio to very high energy, we performed a broad-band modelling from two types of emission scenarios. The results from a one zone lepto-hadronic and a multizone leptonic models are compared and discussed. On the grounds of energetics, our analysis favours a leptonic multizone model. Models associated to the X-ray variability constraint support previous results, suggesting a BL Lac nature of PKS 0625-354 with, however, a large-scale jet structure typical of a radio galaxy.

KW - Galaxies: active

KW - Galaxies: individual: PKS 0625-354

KW - Galaxies: jets

KW - Gamma-rays: galaxies

KW - Radiation mechanisms: non-thermal

UR - http://www.scopus.com/inward/record.url?scp=85052199128&partnerID=8YFLogxK

U2 - 10.1093/mnras/sty439

DO - 10.1093/mnras/sty439

M3 - Article

AN - SCOPUS:85052199128

SN - 0035-8711

VL - 476

SP - 4187

EP - 4198

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

IS - 3

ER -

H.E.S.S. discovery of very high energy γ -ray emission from PKS 0625-354

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this