Discovery of very high energy gamma-ray emission coincident with molecular clouds in the W 28 (G6.4-0.1) field

被引:231
作者
Aharonian, F. [1 ,14 ]
Akhperjanian, A. G. [2 ]
Bazer-Bachi, A. R. [3 ]
Behera, B. [15 ]
Beilicke, M. [4 ]
Benbow, W. [1 ]
Berge, D. [1 ]
Bernloehr, K. [1 ,5 ]
Boisson, C. [6 ]
Bolz, O. [1 ]
Borrel, V. [3 ]
Braun, I. [1 ]
Brion, E. [7 ]
Brown, A. M. [8 ]
Buehler, R. [1 ]
Bulik, T. [25 ]
Buesching, I. [9 ]
Boutelier, T. [18 ]
Carrigan, S. [1 ]
Chadwick, P. M. [8 ]
Chounet, L. -M. [10 ]
Clapson, A. C. [1 ]
Coignet, G. [11 ]
Cornils, R. [4 ]
Costamante, L. [1 ]
Degrange, B. [10 ]
Dickinson, H. J. [8 ]
Djannati-Atai, A. [12 ,13 ]
Domainko, W. [1 ]
Drury, L. O'C. [14 ]
Dubus, G. [10 ]
Dyks, J. [25 ]
Egberts, K. [1 ]
Emmanoulopoulos, D. [15 ]
Espigat, P. [12 ,13 ]
Farnier, C. [16 ]
Feinstein, F. [16 ]
Fiasson, A. [16 ]
Foerster, A.
Fontaine, G. [10 ]
Fukui, Y. [26 ]
Funk, Seb. [5 ]
Funk, S. [1 ]
Fuessling, M. [5 ]
Gallant, Y. A. [16 ]
Giebels, B. [10 ]
Glicenstein, J. F. [7 ]
Glueck, B. [17 ]
Goret, P. [7 ]
Hadjichristidis, C. [8 ]
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 Berlin, Germany
[5] Humboldt Univ, Inst Phys, D-12489 Berlin, Germany
[6] Observ Paris, CNRS, LUTH, Sect Meudon,UMR 8102, F-92195 Meudon, France
[7] CE Saclay, CEA, DAPNIA, 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, CNRS, IN2P3, Lab Leprince Ringuet, F-91128 Palaiseau, France
[11] CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France
[12] APC, F-75231 Paris, France
[13] Univ Paris 07, Observ Paris, CEA, CNRS,UMR 7164, F-75221 Paris 05, France
[14] Dublin Inst Adv Studies, Dublin 2, Ireland
[15] Heidelberg Univ, D-69117 Heidelberg, Germany
[16] Univ Montpellier 2, IN2P3, CNRS, Lab Phys Theor & Astroparticules, F-34095 Montpellier 5, France
[17] Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany
[18] Univ Grenoble 1, CNRS, INSU, Lab Astrophys Grenoble, F-38041 Grenoble 9, France
[19] Univ Tubingen, Inst Astron & Astrophys, D-72076 Tubingen, Germany
[20] Univ Paris 07, Univ Paris 06, LPNHE, CNRS,IN2P3, F-75252 Paris 5, France
[21] Charles Univ Prague, Inst Particle & Nucl Phys, CR-18000 Prague 8, Czech Republic
[22] Ruhr Univ Bochum, Lehrstuhl Weltraum & Astrophys 4, Inst Theoret Phys, D-44780 Bochum, Germany
[23] Univ Namibia, Windhoek, Namibia
[24] Uniwersytet Jagiellonski, Astron Observ, Krakow, Poland
[25] Nicholas Copernicus Astron Ctr, Warsaw, Poland
[26] Nagoya Univ, Dept Astrophys, Chikusa Ku, Nagoya, Aichi 4648602, Japan
基金
英国科学技术设施理事会;
关键词
gamma rays : observations;
D O I
10.1051/0004-6361:20077765
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Aims. Observations of shell-type supernova remnants (SNRs) in the GeV to multi-TeV gamma-ray band, coupled with those at millimetre radio wavelengths, are motivated by the search for cosmic-ray accelerators in our Galaxy. The old-age mixed-morphology SNRW28 (distance similar to 2 kpc) is a prime target due to its interaction with molecular clouds along its northeastern boundary and other clouds situated nearby. Methods. We observed the W28 field (for similar to 40 h) at very high energy (VHE) gamma-ray energies (E > 0.1 TeV) with the HESS. Cherenkov telescopes. A reanalysis of EGRET E > 100 MeV data was also undertaken. Results from the NANTEN 4 m telescope Galactic plane survey and other CO observations were used to study molecular clouds. Results. We have discovered VHE gamma-ray emission (HESS J1801-233) coincident with the northeastern boundary of W 28 and a complex of sources (HESS J1800-240A, B and C) similar to 0.5 degrees south of W 28 in the Galactic disc. The EGRET source (GRO J1801-2320) is centred on HESS J1801-233 but may also be related to HESS J1800-240 given the large EGRET point spread function. The VHE differential photon spectra are well fit by pure power laws with indices Gamma similar to 2.3 to 2.7. The spectral indices of HESS J1800-240A, B, and C are consistent within statistical errors. All VHE sources are similar to 10' in intrinsic radius except for HESS J1800-240C, which appears pointlike. The NANTEN (CO)-C-12(J = 1-0) data reveal molecular clouds positionally associating with the VHE emission, spanning a similar to 15 km s(-1) range in local standard of rest velocity. Conclusions. The VHE/molecular cloud association could indicate a hadronic origin for HESS J1801-233 and HESS J1800-240, and several cloud components in projection may contribute to the VHE emission. The clouds have components covering a broad velocity range encompassing the distance estimates for W28 (similar to 2 kpc) and extending up to similar to 4 kpc. Assuming hadronic origin and distances of 2 and 4 kpc for cloud components, the required cosmic-ray density enhancement factors (with respect to the solar value) are in the range similar to 10 to similar to 30. If situated at 2 kpc distance, such cosmic-ray densities may be supplied by SNRs like W 28. Additionally and/or alternatively, particle acceleration may come from several catalogued SNRs and SNR candidates, the energetic ultra compact HII region W 28A2, and the HII regions M 8 and M 20, along with their associated open clusters. Further sub-mm observations would be recommended to probe in detail the dynamics of the molecular clouds at velocites > 10 km s(-1) and their possible connection to W 28.
引用
收藏
页码:401 / U69
页数:11
相关论文
共 80 条
[1]   The extraordinary outflow toward G5.89-0.39 [J].
Acord, JM ;
Walmsley, CM ;
Churchwell, E .
ASTROPHYSICAL JOURNAL, 1997, 475 (02) :693-704
[2]   H.E.S.S. observations of the supernova remnant RX J0852.0-4622:: Shell-type morphology and spectrum of a widely extended very high energy gamma-ray source [J].
Aharonian, F. ;
Akhperjanian, A. G. ;
Bazer-Bachi, A. R. ;
Beilicke, M. ;
Benbow, W. ;
Berge, D. ;
Bernloehr, K. ;
Boisson, C. ;
Bolz, O. ;
Borrel, V. ;
Braun, I. ;
Brown, A. M. ;
Buehler, R. ;
Buesching, I. ;
Carrigan, S. ;
Chadwick, P. M. ;
Chounet, L.-M. ;
Coignet, G. ;
Cornils, R. ;
Costamante, L. ;
Degrange, B. ;
Dickinson, H. J. ;
Djannati-Atai, A. ;
Drury, L. O'C. ;
Dubus, G. ;
Egberts, K. ;
Emmanoulopoulos, D. ;
Espigat, P. ;
Feinstein, F. ;
Ferrero, E. ;
Fiasson, A. ;
Filipovic, M. D. ;
Fontaine, G. ;
Fukui, Y. ;
Funk, Seb. ;
Funk, S. ;
Fussling, M. ;
Gallant, Y. A. ;
Giebels, B. ;
Glicenstein, J. F. ;
Goret, P. ;
Hadjichristidis, C. ;
Hauser, D. ;
Hauser, M. ;
Heinzelmann, G. ;
Henri, G. ;
Hermann, G. ;
Hinton, J. A. ;
Hiraga, J. S. ;
Hoffmann, A. .
ASTROPHYSICAL JOURNAL, 2007, 661 (01) :236-249
[3]   Detection of extended very-high-energy γ-ray emission towards the young stellar cluster Westerlund 2 [J].
Aharonian, F. ;
Akhperjanian, A. G. ;
Bazer-Bachi, A. R. ;
Beilicke, M. ;
Benbow, W. ;
Berge, D. ;
Bernloehr, K. ;
Boisson, C. ;
Bolz, O. ;
Borrel, V. ;
Braun, I. ;
Brion, E. ;
Brown, A. M. ;
Buehler, R. ;
Buesching, I. ;
Boutelier, T. ;
Carrigan, S. ;
Chadwick, P. M. ;
Chounet, L.-M. ;
Coignet, G. ;
Cornils, R. ;
Costamante, L. ;
Degrange, B. ;
Dickinson, H. J. ;
Djannati-Atai, A. ;
Drury, L. O'C. ;
Dubus, G. ;
Egberts, K. ;
Emmanoulopoulos, D. ;
Espigat, P. ;
Farnier, C. ;
Feinstein, F. ;
Ferrero, E. ;
Fiasson, A. ;
Fontaine, G. ;
Funk, Seb. ;
Funk, S. ;
Fuessling, M. ;
Gallant, Y. A. ;
Giebels, B. ;
Glicenstein, J. F. ;
Glueck, B. ;
Goret, P. ;
Hadjichristidis, C. ;
Hauser, D. ;
Heinzelmann, G. ;
Henri, G. ;
Hermann, G. ;
Hinton, J. A. ;
Hoffmann, A. .
ASTRONOMY & ASTROPHYSICS, 2007, 467 (03) :1075-1080
[4]   Primary particle acceleration above 100 TeV in the shell-type supernova remnant RX J1713.7-3946 with deep HESS observations [J].
Aharonian, F. ;
Akhperjanian, A. G. ;
Bazer-Bachi, A. R. ;
Beilicke, M. ;
Benbow, W. ;
Berge, D. ;
Bernloehr, K. ;
Boisson, C. ;
Bolz, O. ;
Borrel, V. ;
Braun, I. ;
Brion, E. ;
Brown, A. M. ;
Buehler, R. ;
Buesching, I. ;
Carrigan, S. ;
Chadwick, P. M. ;
Chounet, L. -M. ;
Coignet, G. ;
Cornils, R. ;
Costamante, L. ;
Degrange, B. ;
Dickinson, H. J. ;
Djannati-Atai, A. ;
Drury, L. O'C. ;
Dubus, G. ;
Egberts, K. ;
Emmanoulopoulos, D. ;
Espigat, P. ;
Feinstein, F. ;
Ferrero, E. ;
Fiasson, A. ;
Fontaine, G. ;
Funk, Seb. ;
Funk, S. ;
Fuessling, M. ;
Gallant, Y. A. ;
Giebels, B. ;
Glicenstein, J. F. ;
Glueck, B. ;
Goret, P. ;
Hadjichristidis, C. ;
Hauser, D. ;
Hauser, M. ;
Heinzelmann, G. ;
Henri, G. ;
Hermann, G. ;
Hinton, J. A. ;
Hoffmann, A. ;
Hofmann, W. .
ASTRONOMY & ASTROPHYSICS, 2007, 464 (01) :235-243
[5]   Energy dependent γ-ray morphology in the pulsar wind nebula HESS J1825-137 [J].
Aharonian, F. ;
Akhperjanian, A. G. ;
Bazer-Bachi, A. R. ;
Beilicke, M. ;
Benbow, W. ;
Berge, D. ;
Bernloehr, K. ;
Boisson, C. ;
Bolz, O. ;
Borrel, V. ;
Braun, I. ;
Brown, A. M. ;
Buehler, R. ;
Buesching, I. ;
Carrigan, S. ;
Chadwick, P. M. ;
Chounet, L. -M. ;
Cornils, R. ;
Costamante, L. ;
Degrange, B. ;
Dickinson, H. J. ;
Djannati-Atai, A. ;
Drury, L. O'C. ;
Dubus, G. ;
Egberts, K. ;
Emmanoulopoulos, D. ;
Espigat, P. ;
Feinstein, F. ;
Ferrero, E. ;
Fiasson, A. ;
Fontaine, G. ;
Funk, Seb. ;
Funk, S. ;
Fuessling, M. ;
Gallant, Y. A. ;
Giebels, B. ;
Glicenstein, J. F. ;
Goret, P. ;
Hadjichristidis, C. ;
Hauser, D. ;
Hauser, M. ;
Heinzelmann, G. ;
Henri, G. ;
Hermann, G. ;
Hinton, J. A. ;
Hoffmann, A. ;
Hofmann, W. ;
Holleran, M. ;
Horns, D. ;
Jacholkowska, A. .
ASTRONOMY & ASTROPHYSICS, 2006, 460 (02) :365-374
[6]   The HESS survey of the inner galaxy in very high energy gamma rays [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-Ataï, A ;
Drury, LO ;
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 .
ASTROPHYSICAL JOURNAL, 2006, 636 (02) :777-797
[7]   A detailed spectral and morphological study of the gamma-ray supernova remnant RX J1713.7-3946 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-Ataï, A ;
Drury, LO ;
Dubus, G ;
Emmanoulopoulos, D ;
Espigat, P ;
Feinstein, F ;
Fontaine, G ;
Fuchs, Y ;
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 ;
Klages, S ;
Komin, N ;
Konopelko, A ;
Latham, IJ ;
Le Gallou, R .
ASTRONOMY & ASTROPHYSICS, 2006, 449 (01) :223-242
[8]   Discovery of very-high-energy γ-rays from the Galactic Centre ridge [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-Ataï, A ;
Drury, LO ;
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, D ;
Hauser, M ;
Heinzelmann, G ;
Henri, G ;
Hermann, G ;
Hinton, JA ;
Hofmann, W ;
Holleran, M ;
Horns, D ;
Jacholkowska, A ;
de Jager, OC ;
Khélifi, B ;
Klages, S ;
Komin, N ;
Konopelko, A ;
Latham, IJ .
NATURE, 2006, 439 (7077) :695-698
[9]   A new population of very high energy gamma-ray sources in the Milky Way [J].
Aharonian, F ;
Akhperjanian, AG ;
Aye, KM ;
Bazer-Bachi, AR ;
Beilicke, M ;
Benbow, W ;
Berge, D ;
Berghaus, P ;
Bernlöhr, K ;
Boisson, C ;
Bolz, O ;
Borgmeier, C ;
Braun, I ;
Breitling, F ;
Brown, AM ;
Gordo, JB ;
Chadwick, PM ;
Chounet, LM ;
Cornils, R ;
Costamante, L ;
Degrange, B ;
Djannati-Ata, A ;
Drury, LO ;
Dubus, G ;
Ergin, T ;
Espigat, P ;
Feinstein, F ;
Fteury, P ;
Fontaine, G ;
Funk, S ;
Gallant, YA ;
Giebels, B ;
Gillessen, S ;
Goret, P ;
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 .
SCIENCE, 2005, 307 (5717) :1938-1942
[10]   The unidentified TeV source (TeV J2032+4130) and surrounding field:: Final HEGRA IACT-system results [J].
Aharonian, F ;
Akhperjanian, A ;
Beilicke, M ;
Bernlöhr, K ;
Börst, HG ;
Bojahr, H ;
Bolz, O ;
Coarasa, T ;
Contreras, J ;
Cortina, J ;
Denninghoff, S ;
Fonseca, V ;
Girma, M ;
Götting, N ;
Heinzelmann, G ;
Hermann, G ;
Heusler, A ;
Hofmann, W ;
Horns, D ;
Jung, I ;
Kankanyan, R ;
Kestel, M ;
Kohnle, A ;
Konopelko, A ;
Kranich, D ;
Lampeitl, H ;
Lopez, M ;
Lorenz, E ;
Lucarelli, F ;
Mang, O ;
Mazin, D ;
Meyer, H ;
Mirzoyan, R ;
Moralejo, A ;
Oña-Wilhelmi, E ;
Panter, M ;
Plyasheshnikov, A ;
Pühlhofer, G ;
de los Reyes, R ;
Rhode, W ;
Ripken, J ;
Rowell, GP ;
Sahakian, V ;
Samorski, M ;
Schilling, M ;
Siems, M ;
Sobzynska, D ;
Stamm, W ;
Tluczykont, M ;
Vitale, V .
ASTRONOMY & ASTROPHYSICS, 2005, 431 (01) :197-202