Volume 464, Number 3, March IV 2007
|Page(s)||L49 - L52|
|Published online||05 February 2007|
Letter to the Editor
Rotation at 1122 Hz and the neutron star structure
N. Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warszawa, Poland
2 LUTh, UMR 8102 du CNRS, Pl. Jules Janssen, 92195 Meudon, France e-mail: [bejger;haensel;jlz]@camk.edu.pl
Accepted: 26 January 2007
Aims.Recent observations of XTE J1739-285 suggest that it contains a neutron star rotating at 1122 Hz. Such rotation imposes bounds on the structure of neutron star in XTE J1739-285. These bounds may be used to constrain poorly known equation of state of dense matter at densities .
Methods.One-parameter families of stationary configurations rotating rigidly at 1122 Hz are constructed, using a precise 2D code solving Einstein equations. Hydrostatic equilibrium solutions are tested for stability with respect to axi-symmetric perturbations. A set of ten diverse EOSs of neutron stars is considered. Hypothetical strange stars are also studied.
Results.For each EOS, the family of possible neutron star models is limited by the mass shedding limit, corresponding to maximum allowed equatorial radius, , and by the instability with respect to the axi-symmetric perturbations, reached at the minimum allowed equatorial radius, Rmin. We get km, and km, with allowed mass . Allowed stars with hyperonic or exotic-phase core are supramassive and have a very narrow mass range. Quark star with accreted crust might be allowed, provided such a model is able to reproduce X-ray bursts from XTE J1739-285.
Key words: dense matter / equation of state / stars: neutron / stars: rotation
© ESO, 2007
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.