OGLE-LMC-ECL-11893: Evidence of an Eclipsing Disk Around Another Companion?

OGLE-LMC-ECL-11893: THE DISCOVERY OF A LONG-PERIOD ECLIPSING BINARY WITH A CIRCUMSTELLAR DISK

Authors:

Dong et al

Abstract:

We report the serendipitous discovery of a disk-eclipse system OGLE-LMC-ECL-11893. The eclipse occurs with a period of 468 days, a duration of about 15 days, and a deep (up to ΔmI ≈ 1.5), peculiar, and asymmetric profile. A possible origin of such an eclipse profile involves a circumstellar disk. The presence of the disk is confirmed by the H-α line profile from the follow-up spectroscopic observations, and the star is identified as Be/Ae type. Unlike the previously known disk-eclipse candidates, the eclipses of OGLE-LMC-ECL-11893 retain the same shape throughout the span of ~17 yr (13 orbital periods), indicating no measurable orbital precession of the disk.