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Effect of metallicity on low mass X-ray binaries in globular clusters

Natalia Ivanova
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Abstract

We propose that the observed difference in the formation rates of bright low-mass X-ray binaries in metal-rich and metal-poor globular clusters can be explained by taking into account the difference in the stellar structure of main sequence donors with masses between ~0.85 Msun and ~1.25 Msun at different metallicities. This difference is caused by the absence of an outer convective zone in metal-poor main sequence stars in this mass range. In the result, magnetic braking, a powerful mechanism of orbital shrinkage, does not operate and dynamically formed main sequence - neutron star binaries fail to start mass transfer or appear as bright low-mass X-ray binaries.

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Natalia Ivanova. 2005-09-18. Effect of metallicity on low mass X-ray binaries in globular clusters. https://doi.org/10.1017/s1743921306008751

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