X-raying the Beating Heart of a Newborn Star: Rotational Modulation of High-energy Radiation from V1647 Ori

TL;DR

This study detects a ~1 day periodicity in X-ray emissions from the protostar V1647 Ori, revealing stable, high-temperature magnetic structures likely heated by accretion processes, and demonstrating long-term stability of protostellar magnetic configurations.

Contribution

It provides the first evidence of stable, near-breakup rotational modulation in X-ray emissions from a young protostar over multiple years.

Findings

Detected ~1 day periodicity in X-ray emission.

Identified high-temperature plasma in dense magnetic footprints.

Showed long-term stability of protostellar magnetic structures.

Abstract

We report a periodicity of ~1 day in the highly elevated X-ray emission from the protostar V1647 Ori during its two recent multiple-year outbursts of mass accretion. This periodicity is indicative of protostellar rotation at near-breakup speed. Modeling of the phased X-ray light curve indicates the high-temperature (~50 MK), X-ray-emitting plasma, which is most likely heated by accretion-induced magnetic reconnection, resides in dense (>~5e10 cm-3), pancake-shaped magnetic footprints where the accretion stream feeds the newborn star. The sustained X-ray periodicity of V1647 Ori demonstrates that such protostellar magnetospheric accretion configurations can be stable over timescales of years.