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Full-Text Articles in Physical Sciences and Mathematics
A Search For Very High-Energy Gamma Rays From The Missing Link Binary Pulsar J1023+0038 With Veritas, P. T. Reynolds, Et Al
A Search For Very High-Energy Gamma Rays From The Missing Link Binary Pulsar J1023+0038 With Veritas, P. T. Reynolds, Et Al
Physical Sciences Publications
The binary millisecond radio pulsar PSR J1023+0038 exhibits many characteristics similar to the gamma-ray binary system PSR B1259–63/LS 2883, making it an ideal candidate for the study of high-energy nonthermal emission. It has been the subject of multiwavelength campaigns following the disappearance of the pulsed radio emission in 2013 June, which revealed the appearance of an accretion disk around the neutron star. We present the results of very high energy (VHE) gamma-ray observations carried out by the Very Energetic Radiation Imaging Telescope Array System before and after this change of state. Searches for steady and pulsed emission of both data …
Very High Energy Observations Of The Binaries V 404 Cyg And 4u 0115+634 During Giant X-Ray Outbursts, P. T. Reynolds, Et Al
Very High Energy Observations Of The Binaries V 404 Cyg And 4u 0115+634 During Giant X-Ray Outbursts, P. T. Reynolds, Et Al
Physical Sciences Publications
Transient X-ray binaries produce major outbursts in which the X-ray flux can increase over the quiescent level by factors as large as 107. The low-mass X-ray binary V 404 Cyg and the high-mass system 4U 0115+634 underwent such major outbursts in 2015 June and October, respectively. We present here observations at energies above hundreds of GeV with the VERITAS observatory taken during some of the brightest X-ray activity ever observed from these systems. No gamma-ray emission has been detected by VERITAS in 2.5 hr of observations of the microquasar V 404 Cyg from 2015, June 20–21. The upper flux limits …
Exceptionally Bright Tev Flares From The Binary Ls I+61 Degrees 303, P. T. Reynolds, Et Al
Exceptionally Bright Tev Flares From The Binary Ls I+61 Degrees 303, P. T. Reynolds, Et Al
Physical Sciences Publications
The TeV binary system LS I +61° 303 is known for its regular, non-thermal emission pattern that traces the orbital period of the compact object in its 26.5 day orbit around its B0 Ve star companion. The system typically presents elevated TeV emission around apastron passage with flux levels between 5% and 15% of the steady flux from the Crab Nebula (>300 GeV). In this article, VERITAS observations of LS I +61° 303 taken in late 2014 are presented, during which bright TeV flares around apastron at flux levels peaking above 30% of the Crab Nebula flux were detected. …
Veritas Observations Of The Microquasar Cygnus X-3, P. T. Reynolds, Et Al
Veritas Observations Of The Microquasar Cygnus X-3, P. T. Reynolds, Et Al
Physical Sciences Publications
We report results from TeV gamma-ray observations of the microquasar Cygnus X-3. The observations were made with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) over a time period from 2007 June 11 to 2011 November 28. VERITAS is most sensitive to gamma rays at energies between 85 GeV and 30 TeV. The effective exposure time amounts to a total of about 44 hr, with the observations covering six distinct radio/X-ray states of the object. No significant TeV gamma-ray emission was detected in any of the states, nor with all observations combined. The lack of a positive signal, especially …