SRG/ART-XC discovery of pulsations from RX J0535.0-6700: another X-ray pulsar in the LMC

TL;DR

The paper reports the first detection of X-ray pulsations from RX J0535.0-6700 in the LMC, confirming it as a neutron star with a magnetic field, and highlights its variability and classification as a Be-type X-ray pulsar.

Contribution

First detection of X-ray pulsations from RX J0535.0-6700, establishing it as a neutron star in the LMC and expanding the catalog of Be-type X-ray pulsars.

Findings

Detected ~106 s X-ray pulsations confirming neutron star nature.

Archival data support pulsation detection.

IR variability suggests disk evolution.

Abstract

Using the Mikhail Pavlinsky ART-XC onboard the SRG observatory we have detected, for the first time, X-ray pulsations with a period of ~106 s from the poorly-studied high-mass X-ray binary RX J0535.0-6700 located in the Large Magellanic Cloud (LMC), thus proving that the accretor is a neutron star with strong magnetic field. Pulsations with similar period were also found in archival archival data from Chandra and XMM-Newton telescopes. Using photometry from WISE we shown that the source demonstrate significant variability in IR during the last twenty years, which could be caused by a secular evolution of the decretion disk. This discovery makes RX J0535.0-6700 another member of the large family of X-ray pulsars with Be-type companions in the LMC.