Evidence for VHE γ-ray emission from the distant BL Lac PG 1553+113

被引：75

作者：

Aharonian, F ^{[1
]}

Akhperjanian, AG

Bazer-Bachi, AR

Beilicke, M

Benbow, W

Berge, D

Bernlöhr, K

Boisson, C

Bolz, O

Borrel, V

Braun, I

Breitling, F

Brown, AM

Bühler, R

Carrigan, S

Chadwick, PM

Chounet, LM

Cornils, R

Costamante, L

Degrange, B

Dickinson, HJ

Djannati-Ataï, A

Drury, LO

Dubus, G

Egberts, K

Emmanoulopoulos, D

Espigat, P

Feinstein, F

Fontaine, G

Funk, S

Gallant, YA

Giebels, B

Glicenstein, JF

Goret, P

Hadjichristidis, C

Hauser, D

Hauser, M

Heinzelmann, G

Henri, G

Hermann, G

Hinton, JA

Hofmann, W

Holleran, M

Horns, D

Jacholkowska, A

de Jager, OC

Khélifi, B

Komin, N

Konopelko, A

Latham, IJ

机构：

[1] Max Planck Inst Kernphys, D-69117 Heidelberg, Germany

[2] Yerevan Phys Inst, Yerevan, Armenia

[3] UPS, Ctr Etud Spatiale Rayonnements, CNRS, Toulouse, France

[4] Univ Hamburg, Inst Experimentalphys, Hamburg, Germany

[5] Humboldt Univ, Inst Phys, Berlin, Germany

[6] Observ Paris, CNRS, LUTH, UMR 8102, F-92195 Meudon, France

[7] Univ Durham, Dept Phys, Durham DH1 3HP, England

[8] Ecole Polytech, CNRS, Lab Leprince Ringuet, IN2P3, F-91128 Palaiseau, France

[9] Univ Paris 07, CNRS, UMR 7164, APC,CEA,Observ Paris, Paris, France

[10] Dublin Inst Adv Studies, Dublin, Ireland

[11] Landessternwarte Konigstuhl, D-6900 Heidelberg, Germany

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

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

[14] CE Saclay, DAPNIA DSM CEA, Gif Sur Yvette, France

[15] NW Univ, Unit Space Phys, Potchefstroom, South Africa

[16] Univ Paris 06, Lab Phys Nucl & Hautes Energies, IN2P3, CNRS, F-75252 Paris 05, France

[17] Univ Paris 07, Lab Phys Nucl & Hautes Energies, IN2P3, CNRS, F-75221 Paris 05, France

[18] Charles Univ Prague, Inst Nucl & Particle Phys, Prague, Czech Republic

[19] Ruhr Univ Bochum, Inst Theoret Phys, Lehrstuhl 4, D-4630 Bochum, Germany

[20] Univ Namibia, Windhoek, Namibia

来源：

ASTRONOMY & ASTROPHYSICS | 2006年 / 448卷 / 02期

关键词：

galaxies : active; BL lacertae objects : individual : PG1553+113; gamma rays : observations;

D O I：

10.1051/0004-6361:200600010

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The high-frequency peaked BL Lac PG1553+ 113 was observed in 2005 with the HESS stereoscopic array of imaging atmospheric-Cherenkov telescopes in Namibia. Using the HESS standard analysis, an excess was measured at the 4.0 sigma level in these observations (7.6 hours live time). Three alternative, lower-threshold analyses yield > 5 sigma excesses. The observed integral flux above 200 GeV is (4.8 +/- 1. 3(stat) +/- 1.0(syst)) x 10(-12) cm(-2) s(-1), and shows no evidence for variability. The measured energy spectrum is characterized by a very soft power law (photon index of Gamma = 4.0 +/- 0.6). Although the redshift of PG1553+ 113 is unknown, there are strong indications that it is greater than z = 0.25 and possibly larger than z = 0.78. The observed spectrum is interpreted in the context of VHE gamma-ray absorption by the Extragalactic Background Light, and is used to place an upper limit on the redshift of z < 0.74.

引用

页码：L19 / L23

页数：5

共 26 条

[1] Observations of selected AGN with HESS [J].

Aharonian, F ;

Akhperjanian, AG ;

Bazer-Bachi, AR ;

Beilicke, M ;

Benbow, W ;

Berge, D ;

Bernlöhr, K ;

Boisson, C ;

Bolz, O ;

Borrel, V ;

Braun, I ;

Breitling, F ;

Brown, AM ;

Chadwick, PM ;

Chounet, LM ;

Cornils, R ;

Costamante, L ;

Degrange, B ;

Dickinson, HJ ;

Djannati-Atai, A ;

Drury, LOC ;

Dubus, G ;

Emmanoulopoulos, D ;

Espigat, P ;

Feinstein, F ;

Fontaine, G ;

Fuchs, Y ;

Funk, S ;

Gallant, YA ;

Giebels, B ;

Gillessen, S ;

Glicenstein, JF ;

Goret, P ;

Hadjichristidis, C ;

Hauser, M ;

Heinzelmann, G ;

Henri, G ;

Hermann, G ;

Hinton, JA ;

Hofmann, W ;

Holleran, M ;

Horns, D ;

Jacholkowska, A ;

de Jager, OC ;

Khélifi, B ;

Komin, N ;

Konopelko, A ;

Latham, IJ ;

Le Gallou, R ;

Lemière, A .

ASTRONOMY & ASTROPHYSICS, 2005, 441 (02) :465-472

[2] Discovery of VHE gamma rays from PKS 2005-489 [J].

Aharonian, F ;

Akhperjanian, AG ;

Aye, KM ;

Bazer-Bachi, AR ;

Beilicke, MB ;

Benbow, W ;

Berge, D ;

Berghaus, P ;

Bernlöhr, K ;

Boisson, C ;

Bolz, O ;

Braun, I ;

Breitling, F ;

Brown, AM ;

Gordo, JB ;

Chadwick, PM ;

Chounet, LM ;

Cornils, R ;

Costamante, L ;

Degrange, B ;

Djannati-Ataï, A ;

Drury, LOC ;

Dubus, G ;

Emmanoulopoulos, D ;

Espigat, P ;

Feinstein, F ;

Fleury, P ;

Fontaine, G ;

Fuchs, Y ;

Funk, S ;

Gallant, YA ;

Giebels, B ;

Gillessen, S ;

Glicenstein, JF ;

Goret, P ;

Hadjichristidis, C ;

Hauser, M ;

Heinzelmann, G ;

Henri, G ;

Hermann, G ;

Hinton, JA ;

Hofmann, W ;

Holleran, M ;

Horns, D ;

de Jager, OC ;

Khélifi, B ;

Komin, N ;

Konopelko, A ;

Latham, IJ ;

Le Gallou, R .

ASTRONOMY & ASTROPHYSICS, 2005, 436 (02) :L17-L20

[3] HESS observations of PKS 2155-304 [J].

Aharonian, F ;

Akhperjanian, AG ;

Aye, KM ;

Bazer-Bachi, AR ;

Beilicke, M ;

Benbow, W ;

Berge, D ;

Berghaus, P ;

Bernlöhr, K ;

Bolz, O ;

Boisson, C ;

Borgmeier, C ;

Breitling, F ;

Brown, AM ;

Gordo, JB ;

Chadwick, PM ;

Chitnis, VR ;

Chounet, LM ;

Cornils, R ;

Costamante, L ;

Degrange, B ;

Djannati-Ataï, AD ;

Drury, LO ;

Ergin, T ;

Espigat, P ;

Feinstein, F ;

Fleury, P ;

Fontaine, G ;

Funk, S ;

Gallant, YA ;

Giebels, B ;

Gillessen, S ;

Goret, P ;

Guy, J ;

Hadjichristidis, C ;

Hauser, M ;

Heinzelmann, G ;

Henri, G ;

Hermann, G ;

Hinton, JA ;

Hofmann, W ;

Holleran, M ;

Horns, D ;

de Jager, OC ;

Jung, I ;

Khélifi, B ;

Komin, N ;

Konopelko, A ;

Latham, IJ ;

Le Gallou, R .

ASTRONOMY & ASTROPHYSICS, 2005, 430 (03) :865-875

[4] Calibration of cameras of the HESS detector [J].

Aharonian, F ;

Akhperjanian, AG ;

Aye, KM ;

Bazer-Bachi, AR ;

Beilicke, M ;

Benbow, W ;

Berge, D ;

Berghaus, P ;

Bernlöhr, K ;

Bolz, O ;

Boisson, C ;

Borgmeier, C ;

Breitling, F ;

Brown, AM ;

Chadwick, PM ;

Chitnis, VR ;

Chounet, LM ;

Cornils, R ;

Costamante, L ;

Degrange, B ;

de Jager, OC ;

Djannati-Ataï, A ;

Drury, LOC ;

Ergin, T ;

Espigat, P ;

Feinstein, F ;

Fleury, P ;

Fontaine, G ;

Funk, S ;

Gallant, YA ;

Giebels, B ;

Gillessen, S ;

Goret, P ;

Guy, J ;

Hadjichristidis, C ;

Hauser, M ;

Heinzelmann, G ;

Henri, G ;

Hermann, G ;

Hinton, J ;

Hofmann, W ;

Holleran, M ;

Horns, D ;

Jung, I ;

Khélifi, B ;

Komin, N ;

Konopelko, A ;

Latham, IJ ;

Le Gallou, R ;

Lemoine, M .

ASTROPARTICLE PHYSICS, 2004, 22 (02) :109-125

[5]

AHARONIAN F, 2005, ASTROPH0508073 HESS

[6] TeV candidate BL Lac objects [J].

Costamante, L ;

Ghisellini, G .

ASTRONOMY & ASTROPHYSICS, 2002, 384 (01) :56-71

[7]

DENAUROIS M, 2003, P 28 INT COSM RAY C, P2907

[8] Six years of BeppoSAX observations of blazars:: A spectral catalog [J].

Donato, D ;

Sambruna, RM ;

Gliozzi, M .

ASTRONOMY & ASTROPHYSICS, 2005, 433 (03) :1163-U109

[9] PG-1553+11 - A BRIGHT OPTICALLY SELECTED BL-LACERTAE OBJECT [J].

FALOMO, R ;

TREVES, A .

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 1990, 102 (656) :1120-1125

[10]

GIOMMI P, 1995, ASTRON ASTROPHYS SUP, V109, P267

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