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arXiv · 1711.05081

The apparent decay of pulsar magnetic fields

Anton Biryukov·Artyom Astashenok·Sergey Karpov·Gregory Beskin
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Abstract

Neutron stars are extremely strong cosmic magnets which fields are expected to decay with time. Here we report on the simple test of this process. Adopting a novel approach, we have estimated surface magnetic fields $B$ for 76 radiopulsars (the most numerous subclass of the known isolated neutron stars) which ages $t$ are known independently. Focusing on the accurate evaluation of the precision of both quantities, we determined a significant power-law trend $B(t) \propto t^{-\beta}$ with index $\beta = 0.19^{+0.05}_{-0.06}$ at 95\% C.L. The effects of the observational selection turn this value into the upper limit for the intrinsic field decay rate. If so, then neutron star crusts are close to the "impurity-free crystals", which results in a relatively slow magnetic fields decay.

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Anton Biryukov, Artyom Astashenok, Sergey Karpov, Gregory Beskin. 2017-11-14. The apparent decay of pulsar magnetic fields. https://doi.org/10.1088/1742-6596%2F932%2F1%2F012044

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