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Full-Text Articles in Astrophysics and Astronomy

Veritas Observations Of The Unusual Extragalactic Transient Swift J164449.3+573451, P. T. Reynolds, Et Al Aug 2011

Veritas Observations Of The Unusual Extragalactic Transient Swift J164449.3+573451, P. T. Reynolds, Et Al

Physical Sciences Publications

We report on very high energy (>100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the Swift Observatory and later detected by multiple radio, optical, and X-ray observatories. A total exposure of 28 hr was obtained on Swift J164449.3+573451 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) during 2011 March 28-April 15. We do not detect the source and place a differential upper limit on the emission at 500 GeV during these observations of 1.4 × 10–12 erg cm–2 s–1 (99% confidence level). We also present time-resolved upper limits and use a …


Discovery Of Tev Gamma Ray Emission From Tycho's Supernova Remnant, P. T. Reynolds, Et Al Mar 2011

Discovery Of Tev Gamma Ray Emission From Tycho's Supernova Remnant, P. T. Reynolds, Et Al

Physical Sciences Publications

We report the discovery of TeV gamma-ray emission from the Type Ia supernova remnant (SNR) G120.1+1.4, known as Tycho's SNR. Observations performed in the period 2008-2010 with the VERITAS ground-based gamma-ray observatory reveal weak emission coming from the direction of the remnant, compatible with a point source located at 00h25m270, + 64°10'50'' (J2000). The TeV photon spectrum measured by VERITAS can be described with a power law dN/dE = C(E/3.42 TeV)–Γ with Γ = 1.95 ± 0.51stat ± 0.30sys and C = (1.55 ± 0.43stat ± 0.47sys) × 10–14 cm–2 s–1 TeV–1. The integral …


The Two-Component Jet Of Grb 080413b, R. Filgas, T. Krühler, J. Greiner, A. Rau, E. Palazzi, S. Klose, P. Schady, A. Rossi, P. M.J. Afonso, L. A. Antonelli, C. Clemens, S. Covino, P. D’Avanzo, A. Küpcü Yoldas, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares, Adria Updike, A. Yoldas Jan 2011

The Two-Component Jet Of Grb 080413b, R. Filgas, T. Krühler, J. Greiner, A. Rau, E. Palazzi, S. Klose, P. Schady, A. Rossi, P. M.J. Afonso, L. A. Antonelli, C. Clemens, S. Covino, P. D’Avanzo, A. Küpcü Yoldas, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

Aims. The quick and precise localization of GRBs by the Swift telescope allows the early evolution of the afterglow light curve to be captured by ground-based telescopes. With GROND measurements we can investigate the optical/near-infrared light curve of the afterglow of gamma-ray burst 080413B in the context of late rebrightening. Methods. Multi-wavelength follow-up observations were performed on the afterglow of GRB 080413B. X-ray emission was detected by the X-ray telescope onboard the Swift satellite and obtained from the public archive. Optical and near-infrared photometry was performed with the seven-channel imager GROND mounted at the MPG/ESO 2.2 m telescope and additionally …