GINGA observation of the X-ray pulsar 1E 2259+586 in the supernova remnant G109.1-1.0
Author
Japanese:
Koyama, K.,
Nagase, F.,
Ogawara, Y.,
Shinoda, K.,
河合 誠之,
Jones, M. H.,
Williams, O. R.,
Watson, M. G.,
Makishima, K.,
Ohashi, T..
English:
Koyama, K.,
Nagase, F.,
Ogawara, Y.,
Shinoda, K.,
Kawai, N.,
Jones, M. H.,
Williams, O. R.,
Watson, M. G.,
Makishima, K.,
Ohashi, T..
Language
English
Journal/Book name
Japanese:
English:
Publications of the Astronomical Society of Japan
Volume, Number, Page
Vol. 41
pp. 461-471
Published date
1989
Publisher
Japanese:
English:
Conference name
Japanese:
English:
Conference site
Japanese:
English:
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.