Observations of the Crab pulsar and nebula by the EGRET telescope on the Compton Gamma-Ray Observatory

Abstract

view Abstract Citations (167) References (35) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Observations of the Crab Pulsar and Nebula by the EGRET Telescope on the Compton Gamma-Ray Observatory Nolan, P. L. ; Arzoumanian, Z. ; Bertsch, D. L. ; Chiang, J. ; Fichtel, C. E. ; Fierro, J. M. ; Hartman, R. C. ; Hunter, S. D. ; Kanbach, G. ; Kniffen, D. A. ; Kwok, P. W. ; Lin, Y. C. ; Mattox, J. R. ; Mayer-Hasselwander, H. A. ; Michelson, P. F. ; von Montigny, C. ; Nel, H. I. ; Nice, D. ; Pinkau, K. ; Rothermel, H. ; Schneid, E. ; Sommer, M. ; Sreekumar, P. ; Taylor, J. H. ; Thompson, D. J. Abstract The Crab pulsar and nebula were observed three times in 1991 April to June by the Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory (CGRO): April 23 to May 7, May 16 to 30, and June 8 to 15. The results of analysis of the gamma-ray emission in the energy range from 50 MeV to more than 10 GeV are reported. The observed gamma-ray light curve exhibits two peaks separated in phase by 0.40 +/- 0.02, consistent with previous observations. The total pulsed emission from the Crab pulsar is found to be well represented by a power-law spectrum, softer than the spectrum measured by COS B (Clear et al., 1987). The interpulse emission has a harder spectrum than either of the pulses. The evidence for pulsed emission above 5 GeV in the EGRET data is not conclusive. Unpulsed emission in the energy range 50 MeV to 5 GeV was detected, with an indication of a hardening of the unpulsed spectrum above about 1 GeV. There was a significant change in the light curve over the 2 months of these observations, although the shape of the spectrum remained constant. Publication: The Astrophysical Journal Pub Date: June 1993 DOI: 10.1086/172699 Bibcode: 1993ApJ...409..697N Keywords: Crab Nebula; Gamma Ray Astronomy; Gamma Ray Observatory; Gamma Ray Telescopes; Pulsars; Light Curve; Spaceborne Astronomy; Astronomy; GAMMA RAYS: OBSERVATIONS; ISM: INDIVIDUAL NAME: CRAB NEBULA; STARS: PULSARS: INDIVIDUAL NAME: CRAB NEBULA full text sources ADS | data products SIMBAD (2) HEASARC (1)