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The Birthrate of Magnetars

Ramandeep Gill·Jeremy Heyl
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Abstract

Magnetars, neutron stars with ultra strong magnetic fields ($B\sim 10^{14} - 10^{15}$G), manifest their exotic nature in the form of soft gamma-ray repeaters and anomalous X-ray pulsars. This study estimates the birthrate of magnetars to be $\sim$ 0.22 per century with a galactic population comprising of $\sim$17 objects. A population synthesis was carried out based on the five anomalous X-ray pulsars detected in the ROSAT All-Sky Survey by comparing their number to that of massive OB stars in a well defined volume. Additionally, the group of seven X-ray dim isolated neutron stars detected in the same survey were found to have a birthrate of $\sim$ 2 per century with a galactic population of $\sim$ 22,000 objects.

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Ramandeep Gill, Jeremy Heyl. 2007-09-07. The Birthrate of Magnetars. https://doi.org/10.1111/j.1365-2966.2007.12254.x

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