Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory

P. L. Nolan; Z. Arzoumanian; D. L. Bertsch; J. Chiang; C. E. Fichtel; J. M. Fierro; R. C. Hartman; S. D. Hunter; G. Kanbach; D. A. Kniffen; P. W. Kwok; Y. C. Lin; J. R. Mattox; H. A. Mayer-Hasselwander; P. F. Michelson; C. Von Montigny; H. I. Nel; D. Nice; K. Pinkau; H. Rothermel; E. Schneid; M. Sommer; P. Sreekumar; J. H. Taylor; D. J. Thompson

doi:10.1086/172699

Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory

P. L. Nolan^*
, Z. Arzoumanian
, D. L. Bertsch
, J. Chiang
, C. E. Fichtel
, J. M. Fierro
, R. C. Hartman
, S. D. Hunter
, G. Kanbach
, D. A. Kniffen
, P. W. Kwok
, Y. C. Lin
, J. R. Mattox
, H. A. Mayer-Hasselwander
, P. F. Michelson
, C. Von Montigny
, H. I. Nel
, D. Nice
, K. Pinkau
, H. Rothermel

E. Schneid, M. Sommer, P. Sreekumar, J. H. Taylor, D. J. Thompson

^*Corresponding author for this work

Manipal Centre for Natural Sciences, Manipal

Research output: Contribution to journal › Article › peer-review

130 Citations (Scopus)

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 of the form (4.11 ± 0.16) × 10^-9(E/274 MeV)^-2.15±0.04 photons cm^-2 s^-1 MeV^-1 , softer than the spectrum measured by COS B (Clear et al. 1987). The interpuise 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.

Original language	English
Pages (from-to)	697-704
Number of pages	8
Journal	Astrophysical Journal
Volume	409
Issue number	2
DOIs	https://doi.org/10.1086/172699
Publication status	Published - 1993

All Science Journal Classification (ASJC) codes

Astronomy and Astrophysics
Space and Planetary Science

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10.1086/172699

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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., ... Thompson, D. J. (1993). Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory. Astrophysical Journal, 409(2), 697-704. https://doi.org/10.1086/172699

@article{04364c7589d547848df230d3200469d3,

title = "Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory",

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 of the form (4.11 ± 0.16) × 10-9(E/274 MeV)-2.15±0.04 photons cm-2 s-1 MeV-1 , softer than the spectrum measured by COS B (Clear et al. 1987). The interpuise 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.",

author = "Nolan, \{P. L.\} and Z. Arzoumanian and Bertsch, \{D. L.\} and J. Chiang and Fichtel, \{C. E.\} and Fierro, \{J. M.\} and Hartman, \{R. C.\} and Hunter, \{S. D.\} and G. Kanbach and Kniffen, \{D. A.\} and Kwok, \{P. W.\} and Lin, \{Y. C.\} and Mattox, \{J. R.\} and Mayer-Hasselwander, \{H. A.\} and Michelson, \{P. F.\} and \{Von Montigny\}, C. and Nel, \{H. I.\} and D. Nice and K. Pinkau and H. Rothermel and E. Schneid and M. Sommer and P. Sreekumar and Taylor, \{J. H.\} and Thompson, \{D. J.\}",

year = "1993",

doi = "10.1086/172699",

language = "English",

volume = "409",

pages = "697--704",

journal = "Astrophysical Journal",

issn = "0004-637X",

publisher = "American Astronomical Society",

number = "2",

}

Nolan, PL, Arzoumanian, Z, Bertsch, DL, Chiang, J, Fichtel, CE, Fierro, JM, Hartman, RC, Hunter, SD, Kanbach, G, Kniffen, DA, Kwok, PW, Lin, YC, Mattox, JR, Mayer-Hasselwander, HA, Michelson, PF, Von Montigny, C, Nel, HI, Nice, D, Pinkau, K, Rothermel, H, Schneid, E, Sommer, M, Sreekumar, P, Taylor, JH & Thompson, DJ 1993, 'Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory', Astrophysical Journal, vol. 409, no. 2, pp. 697-704. https://doi.org/10.1086/172699

TY - JOUR

T1 - Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory

AU - Nolan, P. L.

AU - Arzoumanian, Z.

AU - Bertsch, D. L.

AU - Chiang, J.

AU - Fichtel, C. E.

AU - Fierro, J. M.

AU - Hartman, R. C.

AU - Hunter, S. D.

AU - Kanbach, G.

AU - Kniffen, D. A.

AU - Kwok, P. W.

AU - Lin, Y. C.

AU - Mattox, J. R.

AU - Mayer-Hasselwander, H. A.

AU - Michelson, P. F.

AU - Von Montigny, C.

AU - Nel, H. I.

AU - Nice, D.

AU - Pinkau, K.

AU - Rothermel, H.

AU - Schneid, E.

AU - Sommer, M.

AU - Sreekumar, P.

AU - Taylor, J. H.

AU - Thompson, D. J.

PY - 1993

Y1 - 1993

N2 - 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 of the form (4.11 ± 0.16) × 10-9(E/274 MeV)-2.15±0.04 photons cm-2 s-1 MeV-1 , softer than the spectrum measured by COS B (Clear et al. 1987). The interpuise 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.

AB - 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 of the form (4.11 ± 0.16) × 10-9(E/274 MeV)-2.15±0.04 photons cm-2 s-1 MeV-1 , softer than the spectrum measured by COS B (Clear et al. 1987). The interpuise 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.

UR - https://www.scopus.com/pages/publications/12044257079

UR - https://www.scopus.com/pages/publications/12044257079#tab=citedBy

U2 - 10.1086/172699

DO - 10.1086/172699

M3 - Article

AN - SCOPUS:12044257079

SN - 0004-637X

VL - 409

SP - 697

EP - 704

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 2

ER -

Observations of the Crab pulsar and nebula by the egret telescope on the compton gamma-ray observatory

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