The results from three ASCA observations of AX J0051.6-7311 = RX J0051.9-7311 are reported. Coherent pulsations with a barycentric period of 172.40 +/- 0.03 s were discovered in the third observation, with an exceptionally long exposure time of similar to 177 ks. The X-ray spectrum was found to remain unchanged through these observations, with a photon index of of similar to 0.9. Energy-resolved pulse profiles in the third observation reveal that the pulsations are mostly due to photons with an energy above similar to 2 keV. Archival data of ROSAT and Einstein Observatory indicate that AX J0051.6-7311 exhibits a flux variation having a factor greater than or similar to 20.
机构:
Natl Res Council Canada, Dominion Astrophys Observ, Victoria, BC V8X 4M6, CanadaNatl Res Council Canada, Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada
机构:
Natl Res Council Canada, Dominion Astrophys Observ, Victoria, BC V8X 4M6, CanadaNatl Res Council Canada, Dominion Astrophys Observ, Victoria, BC V8X 4M6, Canada