DISCOVERY OF GeV {gamma}-RAY EMISSION FROM PSR B1259-63/LS 2883
- Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China)
- Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong)
The binary system PSR B1259-63/LS 2883 consists of a 47.8 ms radio pulsar that orbits the companion Be star with a period of 3.4 years in a highly eccentric orbit. The system has been well sampled in radio, X-ray, and TeV {gamma}-ray bands, and shows orbital phase-dependent variability in all observed frequencies. Here we report on the discovery of >100 MeV {gamma}-rays from PSR B1259-63/LS 2883 through the 2010 periastron passage. Using data collected with the Large Area Telescope on board Fermi from 33 days before periastron to 75 days after periastron, PSR B1259-63/LS 2883 was detected at a significance of 13.6 standard deviations. The {gamma}-ray light curve was highly variable over this period, with a changing photon index that correlates with the {gamma}-ray flux. In particular, two major flares that occur after the periastron passage were observed. The onset of {gamma}-ray emission occurs close to, but not at the same orbital phases as, the two disk passages that occur {approx}1 month before and {approx}1 month after the periastron passage. The fact that the GeV orbital light curve is different from that of the X-ray and TeV light curves strongly suggests that GeV {gamma}-ray emission originates from a different component. We speculate that the observed GeV flares may be resulting from Doppler boosting effects.
- OSTI ID:
- 21562530
- Journal Information:
- Astrophysical Journal Letters, Vol. 736, Issue 1; Other Information: DOI: 10.1088/2041-8205/736/1/L10; ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
Similar Records
HIGH-ENERGY OBSERVATIONS OF PSR B1259–63/LS 2883 THROUGH THE 2014 PERIASTRON PASSAGE: CONNECTING X-RAYS TO THE GeV FLARE
DISCOVERY OF EXTENDED AND VARIABLE RADIO STRUCTURE FROM THE GAMMA-RAY BINARY SYSTEM PSR B1259-63/LS 2883