Discovery of 172-s pulsations from a Be/X-ray binary candidate AX J0051.6-7311 in the SMC with ASCA

被引:18
作者
Yokogawa, J
Torii, K
Imanishi, K
Koyama, K
机构
[1] Kyoto Univ, Grad Sch Sci, Dept Phys, Sakyo Ku, Kyoto 6068502, Japan
[2] Natl Space Dev Agcy Japan, Tsukuba, Ibaraki 3058505, Japan
关键词
pulsars : individual (AX J0051.6-7311); stars; emission-line; Be; stars : neutron; X-rays : stars;
D O I
10.1093/pasj/52.5.L37
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
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.
引用
收藏
页码:L37 / L41
页数:5
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