The white dwarf companion to PSR B 0820 + 02 ?
نویسنده
چکیده
We report new spectroscopic and photometric observations of the white dwarf companion to the pulsar PSR B0820+02. The white dwarf is a normal DA white dwarf with an effective temperature of 15000 K and a mass of 0.6 M . The mass and orbital period of this system confirm recent simulations of the evolution of a neutron star – main sequence binary with mass exchange and thus implicitely theoretical predictions of the dependence of the red giant radius on the He-core mass. The cooling age of the white dwarf is larger than the spin-down age of the pulsar, unless a braking index of 2.2 is assumed.
منابع مشابه
ar X iv : a st ro - p h / 95 09 10 1 v 1 1 9 Se p 19 95 Spectroscopy of the white - dwarf companions of PSR 0655 + 64 and 0820 + 02
We present spectra of the white-dwarf companions of the radio pulsars 0655+64 and 0820+02. For the latter, we find a spectrum showing strong lines of hydrogen, i.e., that of a DA star. From modelling these lines, the mass of a white dwarf can, in principle, be determined accurately, thus leading to constraints on the evolution of the binary and the mass of the neutron star. Our present spectrum...
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