The Common Fundamental Plane of X-ray Emissions from Pulsars and Magnetars in Quiescence

Che-Yen Chu; Hsiang-Kuang Chang

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arXiv · 2306.04943

The Common Fundamental Plane of X-ray Emissions from Pulsars and Magnetars in Quiescence

Che-Yen Chu·Hsiang-Kuang Chang

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Abstract

Magnetars are a unique class of neutron stars characterized by their incredibly strong magnetic fields. Unlike normal pulsars whose X-ray emission was driven by rotational energy loss, magnetars exhibit distinct X-ray emissions thought to be driven by their strong magnetic fields. Here we present the results of magnetar X-ray spectra analysis in their quiescent state. Most of the spectra of magnetars can be fitted with a model consisting of a power-law and a black body component. We found that the luminosity of the power-law component can be described by a function of black-body temperature and emission-region radius. The same relation was seen in pulsars whose X-ray emission mechanism is thought to be different. The fact that magnetars and pulsars share a common fundamental plane in the space spanned by non-thermal X-ray luminosity, surface temperature and the radius of the thermally emitting region presents both challenges and hints to theoretical models for a complete comprehension of the magnetospheric emissions from these two classes of neutron stars.

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Che-Yen Chu, Hsiang-Kuang Chang. 2023-06-08. The Common Fundamental Plane of X-ray Emissions from Pulsars and Magnetars in Quiescence. https://arxiv.org/abs/2306.04943

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