Concepedia

Publication | Closed Access

300 GeV gamma rays from VELA X-1

DOI

17

Citations

0

References

1989

Year

A. Carramiñana, P. M. Chadwick, N. A. Dipper, E. W. Lincoln, V. Mannings, T. J. L. McComb, K. J. Orford, S. M. Rayner, K. E. Turver, D. G. Williams
The Astrophysical Journal

Abstract

The high-mass X-ray binary Vela X-1 has been observed using the Narrabri 300 GeV gamma-ray telescope. The results show evidence for pulsed very high energy (VHE) gamma-ray emission, with a conservative overall Rayleigh chance probability of 0.00011. The long-term period derivative during our observations of 1986-1988 was negative, indicating a spin-up similar to that noted between 1975 and 1979. The time-averaged luminosity in VHE gamma rays is estimated to be about 3.6 x 10 to the 34th ergs/s.