Optical identification of the companion to PSR J1911-5958A, the pulsar binary in the outskirts of NGC 6752

C. G. Bassa; F. Verbunt; M. H. van Kerkwijk; L. Homer

doi:10.1051/0004-6361:20031339

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Optical identification of the companion to PSR J1911-5958A, the pulsar binary in the outskirts of NGC 6752

C. G. Bassa·F. Verbunt·M. H. van Kerkwijk·L. Homer

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Abstract

We report on the identification of the optical counterpart of the binary millisecond pulsar PSR J1911-5958A, located in the outskirts of the globular cluster NGC 6752. At the position of the pulsar we find an object with V=22.08, B-V=0.38, U-B=-0.49. The object is blue with respect to the cluster main sequence by 0.8 magnitudes in B-V. We argue that the object is the white dwarf companion of the pulsar. Comparison with white dwarf cooling models shows that this magnitude and colors are consistent with a low-mass white dwarf at the distance of NGC 6752. If associated with NGC 6752, the white dwarf is relatively young, <2 Gyr, which sets constraints on the formation of the binary and its ejection from the core of the globular cluster.

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C. G. Bassa, F. Verbunt, M. H. van Kerkwijk, L. Homer. 2003-09-02. Optical identification of the companion to PSR J1911-5958A, the pulsar binary in the outskirts of NGC 6752. https://doi.org/10.1051/0004-6361%3A20031339

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