Be/X-Ray Binaries: Phenomenology, Variability, and Accretion~Dynamics

Pablo Reig

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arXiv · 2607.18980

Be/X-Ray Binaries: Phenomenology, Variability, and Accretion~Dynamics

Pablo Reig

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Abstract

Be/X-ray binaries constitute the largest and most diverse subgroup of neutron star high-mass X-ray binaries. These systems feature a rapidly rotating Be star surrounded by a circumstellar decretion disk that serves as the primary reservoir of accreted matter onto a strongly magnetized neutron star. While a few Be/X-ray binaries remain persistently active, the majority manifest as hard X-ray transient sources, becoming detectable only during X-ray outbursts. This review synthesizes current understanding of their rich phenomenology across optical and X-ray wavelengths, focusing on variability ocurring over timescales that span from seconds to years.

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Pablo Reig. 2026-07-21. Be/X-Ray Binaries: Phenomenology, Variability, and Accretion~Dynamics. https://arxiv.org/abs/2607.18980

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