Fermi Gamma-ray Space Telescope

High energy gamma-ray emission from PSR B1259-63/SS 2883 during 2014 periastron passage

JIAN LI
Andrea Caliandro, Teddy Cheung, Diego F. Torres, Kent Wood on behalf of the Fermi LAT collaboration

Abstract:

PSR B1259-63/SS 2883 is a gamma-ray binary system containing a radio pulsar in a long (1236.7 days) and elliptical (e~0.87) orbit around a Be star. In its 2010 periastron passage, multiwavelength emission from radio to TeV were observed, as well as an unexpected GeV flare by the Fermi Large Area Telescope (LAT). Here we present the results of LAT monitoring of PSR B1259-63 during its most recent 2014 periastron passage and compare it with the former 2010 periastron. We confirm that the GeV flare is recurrent and similar with 2010 flare in duration, average flux level, spectrum. However, there are interesting differences in the flare properties.