Variability and Spectra of Two Neutron Stars in 47
نویسندگان
چکیده
We report spectral and variability analysis of two quiescent low mass x-ray binaries (previously identified with ROSAT HRI as X5 and X7) in the globular cluster 47 Tuc, from a Chandra ACIS-I observation. X5 demonstrates sharp eclipses with an 8.666±0.008 hr period, as well as dips showing an increased N H column. Their thermal spectra are well-modelled by unmagnetized hydrogen atmospheres of hot neutron stars, most likely heated by transient accretion, with little to no hard power law component.
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