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arXiv · 1602.08522

TeV Gamma-ray Observations of The Galactic Center Ridge By VERITAS

A. Archer·W. Benbow·R. Bird·M. Buchovecky·J. H. Buckley·V. Bugaev·K. Byrum·J. V Cardenzana·M. Cerruti·X. Chen·L. Ciupik·E. Collins-Hughes·M. P. Connolly·J. D. Eisch·A. Falcone·Q. Feng·J. P. Finley·H. Fleischhack·A. Flinders·L. Fortson·A. Furniss·G. H. Gillanders·S. Griffin·J. Grube·G. Gyuk·N. Hakansson·D. Hanna·J. Holder·T. B. Humensky·M. Hutten·C. A. Johnson·P. Kaaret·P. Kar·N. Kelley-Hoskins·M. Kertzman·D. Kieda·M. Krause·F. Krennrich·S. Kumar·M. J. Lang·S. McArthur·A. McCann·K. Meagher·J. Millis·P. Moriarty·R. Mukherjee·D. Nieto·R. A. Ong·N. Park·V. Pelassa·M. Pohl·A. Popkow·E. Pueschel·J. Quinn·K. Ragan·G. Ratliff·P. T. Reynolds·G. T. Richards·E. Roache·J. Rousselle·M. Santander·G. H. Sembroski·K. Shahinyan·A. W. Smith·D. Staszak·I. Telezhinsky·J. V. Tucci·J. Tyler·V. V. Vassiliev·S. P. Wakely·O. M. Weiner·A. Weinstein·A. Wilhelm·D. A. Williams·B. Zitzer·F. Yusef-Zadeh
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Abstract

The Galactic Center Ridge has been observed extensively in the past by both GeV and TeV gamma-ray instruments revealing a wealth of structure, including a diffuse component as well as the point sources G0.9+0.1 (a composite supernova remnant) and Sgr A* (believed to be associated with the supermassive black hole located at the center of our Galaxy). Previous very high energy (VHE) gamma-ray observations with the H.E.S.S. experiment have also detected an extended TeV gamma-ray component along the Galactic plane in the >300 GeV gamma-ray regime. Here we report on observations of the Galactic Center Ridge from 2010-2014 by the VERITAS telescope array in the >2 TeV energy range. From these observations we 1.) provide improved measurements of the differential energy spectrum for Sgr A* in the >2 TeV gamma-ray regime, 2.) provide a detection in the >2 TeV gamma-ray emission from the composite SNR G0.9+0.1 and an improved determination of its multi-TeV gamma-ray energy spectrum, 3.) report on the detection of VER J1746-289, a localized enhancement of >2 TeV gamma-ray emission along the Galactic plane.

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A. Archer, W. Benbow, R. Bird, M. Buchovecky, J. H. Buckley, V. Bugaev, K. Byrum, J. V Cardenzana, M. Cerruti, X. Chen, L. Ciupik, E. Collins-Hughes, M. P. Connolly, J. D. Eisch, A. Falcone, Q. Feng, J. P. Finley, H. Fleischhack, A. Flinders, L. Fortson, A. Furniss, G. H. Gillanders, S. Griffin, J. Grube, G. Gyuk, N. Hakansson, D. Hanna, J. Holder, T. B. Humensky, M. Hutten, C. A. Johnson, P. Kaaret, P. Kar, N. Kelley-Hoskins, M. Kertzman, D. Kieda, M. Krause, F. Krennrich, S. Kumar, M. J. Lang, S. McArthur, A. McCann, K. Meagher, J. Millis, P. Moriarty, R. Mukherjee, D. Nieto, R. A. Ong, N. Park, V. Pelassa, M. Pohl, A. Popkow, E. Pueschel, J. Quinn, K. Ragan, G. Ratliff, P. T. Reynolds, G. T. Richards, E. Roache, J. Rousselle, M. Santander, G. H. Sembroski, K. Shahinyan, A. W. Smith, D. Staszak, I. Telezhinsky, J. V. Tucci, J. Tyler, V. V. Vassiliev, S. P. Wakely, O. M. Weiner, A. Weinstein, A. Wilhelm, D. A. Williams, B. Zitzer, F. Yusef-Zadeh. 2016-02-26. TeV Gamma-ray Observations of The Galactic Center Ridge By VERITAS. https://doi.org/10.3847/0004-637x%2F821%2F2%2F129

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