GINGA observation of the X-ray pulsar 1E 2259+586 in the supernova remnant G 109.1-1.0
Abstract
The X-ray pulsar 1E 2259+586 in the supernova remnant G109.1-1.0 was observed with the Ginga satellite from June 21 to 23, 1987. The heliocentric pulse period is found to be 6.978759 + or - 0.000002 s, confirming a secular spin down rate of 6.2 x 10 to the -13th s/s. The pulsation was observed to have asymmetric double peaks in the energy range from 1 keV to 10 keV. The upper limit on the projected semimajor axis is 0.08 1t-s (3sigma) throughout the period range searched. The constraint on the binary system is discussed in the light of this new upper limit. The energy spectrum of 1E 2259+586 does not show a single power law spectrum but exhibits a complex structure which mimics an emission line at 7.2 keV. An attempt to ascribe the structure to a cyclotron line feature is presented. This interpretation implies a weak magnetic field of 5 x 10 to the 11th G at the neutron star surface of 1E 2259+586.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- 1989
- Bibcode:
- 1989PASJ...41..461K
- Keywords:
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- Ginga Satellite;
- Pulsars;
- Pulse Modulation;
- Satellite Observation;
- Supernova Remnants;
- X Ray Binaries;
- Emission Spectra;
- Energy Spectra;
- Japanese Space Program;
- Line Spectra;
- Neutron Stars;
- Astrophysics