Thermal emission from low-field neutron stars
نویسنده
چکیده
We present a new grid of LTE model atmospheres for weakly magnetic (B <∼ 10 10 G) neutron stars, using opacity and equation of state data from the OPAL project and employing a fully frequency and angle dependent radiation transfer. We discuss the differences to earlier models, including a comparison with a detailed NLTE calculation. As a first application of the new synthetic spectra, we re-analyze the available ROSAT PSPC data of the isolated neutron star candidate RXJ1856.5–3754. Our iron and solar abundance model spectra provide satisfactory fits to the X-ray spectrum and are consistent with the distance of RXJ1856.5–3754 recently measured by the Hubble Space Telescope, although pulse fractions as small as those observed are difficult to obtain for canonical neutron star radii.
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