Green Bank Telescope Observations of the Eclipse of Pulsar “ A ” in the Double Pulsar Binary PSR J 0737 − 3039

We report on the first Green Bank Telescope observations at 427, 820 and 1400 MHz of the newly discovered, highly inclined and relativistic double pulsar binary. We focus on the brief eclipse of PSR J0737−3039A, the faster pulsar, when it passes behind PSR J0737−3039B. We measure a frequency-averaged eclipse duration of 26.6 ± 0.6 s, or 0.00301 ± 0.00008 in orbital phase. The eclipse duration is found to be significantly dependent on radio frequency, with eclipses longer at lower frequencies. Specifically, eclipse duration is well fit by a linear function having slope (−4.52± 0.03)× 10 orbits MHz. We also detect significant asymmetry in the eclipse. Eclipse ingress takes 3.51 ± 0.99 times longer than egress, independent of radio frequency. Additionally, the eclipse lasts (40± 7)× 10 in orbital phase longer after conjunction, also independent of frequency. We detect significant emission from the pulsar on short time scales during eclipse in some orbits. We discuss these results in the context of a model in which the eclipsing material is a shock-heated plasma layer within the slower PSR J0737−3039B’s light cylinder, where the relativistic pressure of the faster pulsar’s wind confines the magnetosphere of the slower pulsar. Subject headings: pulsars: general — pulsars: individual (PSR J0737−3039) — binaries: eclipsing — binaries: general — stars: neutron Department of Physics, Rutherford Physics Building, McGill University, 3600 University Street, Montreal, Quebec, H3A 2T8, Canada Department of Physics and Center for Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 Canada Research Chair; NSERC Steacie Fellow Department of Astronomy, University of California, 601 Campbell Hall, Berkeley, CA 94720 Theoretical Astrophysics Center and Physics Department, University of California, 601 Campbell Hall, Berkeley, CA 94720 KIPAC, Stanford University, P.O. Box 20450, MS 29, Stanford, CA 94309