engleski

TeV gamma-ray emission from PSR J2032+4127/ MT91 213

The VERITAS and MAGIC collaborations report the detection of an enhanced TeV gamma-ray flux from the pulsar/ Be-star binary system PSR J2032+4127/ MT91 213 (RA 20h32m13.13s, Dec +41d27m24.4s, J2000.0). The binary nature of this system was identified in 2015 through radio and gamma-ray timing observations (Lyne et al., MNRAS, 451, 581, 2015). The orbital period is estimated at 45-50 years, with periastron expected to occur around November 2017. The X-ray flux has been steadily increasing as the system approaches periastron (Bird et al., arXiv:1708.04718). PSR J2032+4127 is co-located with the extended TeV gamma-ray source, TeV J2032+4130, and may be physically associated with it. Both VERITAS and MAGIC observations were conducted as part of a coordinated long-term monitoring campaign. The source was observed most recently by VERITAS between 16 September and 27 September 2017 for a total exposure of 15.3 hours. In a preliminary analysis, the integral flux measured by VERITAS above 200 GeV is 4.2e-12 ± 0.7e-12 photons cm^-2 s^-1 (~2% of the Crab Nebula flux), corresponding to approximately twice the flux measured at the same location in archival VERITAS observations from spring 2017. The emission is consistent with a point source at the location of PSR J2032+4127, offset from the center of the previously known extended TeV source. The VERITAS source name is VER J2032+414. The statistical significance of the gamma-ray excess at the pulsar position is 6.8 standard deviations. MAGIC observations comprise 5.6 hours taken between 10 September and 25 September. A preliminary analysis of the MAGIC data indicates a flux of 5.6e-12 ± 1.2e-12 photons cm^-2 s^-1 above 200 GeV, which implies an increase by about a factor of 2 with respect to the mean flux observed by MAGIC in June-August 2017. The MAGIC source name is MAGIC J2032+4127. The gamma-ray flux is predicted to continue to increase over the coming months (e.g. Takata et al., ApJ, 836, 241), and VERITAS and MAGIC observations will continue with highest priority. We strongly encourage coordinated multiwavelength observations.

Gamma Ray ; TeV ; VHE ; Request for Observations ; Binary ; Neutron Star ; Transient ; Pulsar

nije evidentirano