2014/08/27 by I. Sushch, M. Böttcher, Sushch, Iurii +1
Physics and Astronomy · #Astrophysical Phenomena and Observations #FOS: Physical sciences #Gamma-ray bursts and supernovae #High Energy Astrophysical Phenomena (astro-ph.HE) #Pulsars and Gravitational Waves Research
paper · pdf · doi:10.48550/arxiv.1408.6426
openalex publication_date 2014/08/27 · openalex created_date 2022/10/03 · openalex updated_date 2026/07/28
PSR B1259-63/LS 2883 is a very high energy (VHE; E > 100 GeV) \γ-ray\nemitting binary consisting of a 48 ms pulsar orbiting around a Be star with a\nperiod of \∼3.4 years. The Be star features a circumstellar disk which is\ninclined with respect to the orbit in such a way that the pulsar crosses it\ntwice every orbit. The circumstellar disk provides an additional field of\ntarget photons which may contribute to inverse Compton scattering and\n\γ\γ-absorption, leaving a characteristic imprint in the observed\nspectrum of the high energy emission. At GeV energies, the source was detected\nfor the first time during the previous periastron passage which took place on\nDecember 15, 2010. The Fermi Large Area Telescope (LAT) reported a spectacular\nand unexpected \γ-ray flare occurring around 30 days after periastron and\nlasting for about 7 weeks. In this paper, we study the signatures of\nCompton-supported, VHE \γ-ray induced pair cascades in the circumstellar\ndisc of the Be star and their possible contribution to the GeV flux. We show\nthat cascade emission generated in the disk cannot be responsible for the GeV\nflare, but it might explain the GeV emission observed close to periastron. We\nalso show that the \γ\γ-absorption in the disk might explain the\nobserved TeV light curve.\n