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Discovery of 101-s Pulsations from AX J0057.4-7325 in the SMC with ASCA

Jun Yokogawa·Ken'ichi Torii·Takayoshi Kohmura·Kensuke Imanishi·Katsuji Koyama
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Abstract

The results from two ASCA observations of AX J0057.4-7325 = RX J0057.3-7325 are presented. Coherent pulsations with a barycentric period of 101.45 +/- 0.07 s were discovered in the second observation. The X-ray spectrum was found to be hard (photon index ~ 0.9) and unchanged through these observations, except for the flux. The ROSAT archival data show that AX J0057.4-7325 exhibits a flux variation with a factor >~ 10. A discussion on a possible optical counterpart is given.

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Jun Yokogawa, Ken'ichi Torii, Takayoshi Kohmura, Kensuke Imanishi, Katsuji Koyama. 2000-11-02. Discovery of 101-s Pulsations from AX J0057.4-7325 in the SMC with ASCA. https://doi.org/10.1093/pasj%2F52.6.l53

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