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arXiv · 1106.5497

The White Dwarf Companion of a 2 M_sun Neutron Star

Varun B. Bhalerao·S. R. Kulkarni
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Abstract

We report the optical discovery of the companion to the 2 M_sun millisecond pulsar PSR J1614-2230. The optical colors show that the 0.5 M_sun companion is a 2.2 Gyr old He-CO white dwarf. We infer that $\dot{M}$ during the accretion phase is <10^{-2}\dot{M}_{edd}. We show that the pulsar was born with a spin close to its current value, well below the rebirth line. The spin-down parameters, the mass of the pulsar, and the age of the system challenge the simple recycling model for the formation of millisecond pulsars.

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Varun B. Bhalerao, S. R. Kulkarni. 2011-06-27. The White Dwarf Companion of a 2 M_sun Neutron Star. https://doi.org/10.1088/2041-8205%2F737%2F1%2Fl1

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