Details

Autor(en) / Beteiligte

• Adams, C. B.
• Benbow, W.
• Brill, A.
• Brose, R.
• Buchovecky, M.
• Capasso, M.
• Christiansen, J. L.
• Chromey, A. J.
• Daniel, M. K.
• Errando, M.
• Falcone, A.
• Feng, Q.
• Finley, J. P.
• Fortson, L.
• Furniss, A.
• Gent, A.
• Gillanders, G. H.
• Giuri, C.
• Hanna, D.
• Hervet, O.
• Holder, J.
• Hughes, G.
• Humensky, T. B.
• Jin, W.
• Kaaret, P.
• Kelley-Hoskins, N.
• Kertzman, M.
• Kieda, D.
• Krennrich, F.
• Kumar, S.
• Lang, M. J.
• Lundy, M.
• Maier, G.
• Moriarty, P.
• Mukherjee, R.
• Nieto, D.
• Nievas-Rosillo, M.
• O’Brien, S.
• Ong, R. A.
• Otte, A. N.
• Pfrang, K.
• Pohl, M.
• Prado, R. R.
• Pueschel, E.
• Quinn, J.
• Ragan, K.
• Reynolds, P. T.
• Ribeiro, D.
• Richards, G. T.
• Roache, E.
• Ryan, J. L.
• Santander, M.
• Schlenstedt, S.
• Sembroski, G. H.
• Shang, R.
• Stevenson, B.
• Wakely, S. P.
• Weinstein, A.
• Williams, D. A.

Titel

VERITAS Observations of the Galactic Center Region at Multi-TeV Gamma-Ray Energies

Ist Teil von

• The Astrophysical journal, 2021-06, Vol.913 (2), p.115

Ort / Verlag

Philadelphia: The American Astronomical Society

Erscheinungsjahr

2021

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Abstract The Galactic Center (GC) region hosts a variety of powerful astronomical sources and rare astrophysical processes that emit a large flux of nonthermal radiation. The inner 375 pc × 600 pc region, called the Central Molecular Zone, is home to the supermassive black hole Sagittarius A*, massive cloud complexes, and particle accelerators such as supernova remnants (SNRs). We present the results of our improved analysis of the very-high-energy gamma-ray emission above 2 TeV from the GC using 125 hr of data taken with the Very Energetic Radiation Imaging Telescope Array System imaging-atmospheric Cerenkov telescope between 2010 and 2018. The central source VER J1745–290, consistent with the position of Sagittarius A*, is detected at a significance of 38 standard deviations above the background level (38 σ ), and we report its spectrum and light curve. Its differential spectrum is consistent with a power law with exponential cutoff, with a spectral index of , a flux normalization at 5.3 TeV of TeV −1 cm −2 s −1 , and cutoff energy of TeV. We also present results on the diffuse emission near the GC, obtained by combining data from multiple regions along the GC ridge, which yield a cumulative significance of 9.5 σ . The diffuse GC ridge spectrum is best fit by a power law with a hard index of 2.19 ± 0.20, showing no evidence of a cutoff up to 40 TeV. This strengthens the evidence for a potential accelerator of PeV cosmic rays being present in the GC. We also provide spectra of the other sources in our field of view with significant detections, composite SNR G0.9+0.1, and HESS J1746–285.