Millisecond X–Ray Pulsar SAX J1808.4–3658: Limits to the Mass and the Radius of the Compact Star
نویسنده
چکیده
We predict from a survey of equations of state and observations of X–ray pulsations from SAX J1808.4–3658, that the upper limit of the mass of the compact star is 2.27 M⊙ . The corresponding upper limit of the radius comes out to be 9.73 km. We also do a study to estimate the lower limit of the mass of the compact star. Such a limit is very useful to put constraints on equations of state. We also discuss the implications of the upper mass limit for the detection of the source in radio frequencies. We point out that the possible observation of radio–eclipse may be able to rule out several soft equation of state models, by setting a moderately high value for the lower limit of inclination angle.
منابع مشابه
Interior matter estimates of the X-ray pulsar in SAX J1808.4-3658 from mass-radius and rotation measurements
Aims. To constrain the equation of state of super-nuclear density matter and probe the interior composition of the X-ray pulsar in SAX J1808.4-3658. In our estimation, we consider both its persistent 2.49 ms X-ray pulsations discovered by Wijnands and van der Klis from using the Rossi X-ray Timing Explorer, which is interpreted to come from an accreting-powered millisecond X-ray pulsar in the l...
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