DISCOVERY OF HIGH-ENERGY GAMMA-RAY EMISSION FROM THE BINARY SYSTEM PSR B1259-63/LS 2883 AROUND PERIASTRON WITH FERMI
2011 (English)In: Astrophysical Journal Letters, ISSN 2041-8205, Vol. 736, no 1, L11- p.Article in journal (Refereed) Published
We report on the discovery of >= 100 MeV gamma-rays from the binary system PSR B1259-63/LS 2883 using the Large Area Telescope (LAT) on board Fermi. The system comprises a radio pulsar in orbit around a Be star. We report on LAT observations from near apastron to similar to 128 days after the time of periastron, t(p), on 2010 December 15. No gamma-ray emission was detected from this source when it was far from periastron. Faint gamma-ray emission appeared as the pulsar approached periastron. At similar to t(p) + 30 days, the >= 100 MeV gamma-ray flux increased over a period of a few days to a peak flux 20-30 times that seen during the pre-periastron period, but with a softer spectrum. For the following month, it was seen to be variable on daily timescales, but remained at similar to(1-4) x 10(-6) cm(-2) s(-1) before starting to fade at similar to t(p) + 57 days. The total gamma-ray luminosity observed during this period is comparable to the spin-down power of the pulsar. Simultaneous radio and X-ray observations of the source showed no corresponding dramatic changes in radio and X-ray flux between the pre-periastron and post-periastron flares. We discuss possible explanations for the observed gamma-ray-only flaring of the source.
Place, publisher, year, edition, pages
2011. Vol. 736, no 1, L11- p.
binaries: eclipsing, gamma rays: stars, pulsars: individual (PSR B1259-63), X-rays: binaries
IdentifiersURN: urn:nbn:se:su:diva-66599DOI: 10.1088/2041-8205/736/1/L11ISI: 000293138300011OAI: oai:DiVA.org:su-66599DiVA: diva2:468215
authorCount :1722011-12-202011-12-202011-12-20Bibliographically approved