TESS Light Curve of the Interacting Binary W Serpentis

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gies, Douglas R., Shepard, Katherine A., Kar, Aman, Richardson, Noel D.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916690811420672
author Gies, Douglas R.
Shepard, Katherine A.
Kar, Aman
Richardson, Noel D.
author_facet Gies, Douglas R.
Shepard, Katherine A.
Kar, Aman
Richardson, Noel D.
contents The unusual light curve of the massive eclipsing binary W Ser was recently observed with high S/N and fast cadence by the NASA TESS mission. The TESS light curve records two eclipses and relatively fast variations outside of the eclipses. The eclipse timings verify the period increase of the binary, and the period derivative implies a mass transfer rate in excess of 10^{-5} solar masses per year.. The light curve shows a fading trend from just after an eclipse until the start of the next eclipse. The brightest flux source in the system is the accretion torus surrounding the mass gainer star, and we argue that these orbital-phase related fadings are the result of the injection of cooler gas from the mass donor entering the outskirts of the accretion torus. There are cyclic variations in the out-of-eclipse sections of the light curve that vary on a 2.8 day timescale. This equals the orbital period for gas in the outer regions of the accretion torus, so the photometric variations are probably the result of transitory, over-dense regions that form at the rim of the accretion torus.
format Preprint
id arxiv_https___arxiv_org_abs_2504_10608
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle TESS Light Curve of the Interacting Binary W Serpentis
Gies, Douglas R.
Shepard, Katherine A.
Kar, Aman
Richardson, Noel D.
Solar and Stellar Astrophysics
The unusual light curve of the massive eclipsing binary W Ser was recently observed with high S/N and fast cadence by the NASA TESS mission. The TESS light curve records two eclipses and relatively fast variations outside of the eclipses. The eclipse timings verify the period increase of the binary, and the period derivative implies a mass transfer rate in excess of 10^{-5} solar masses per year.. The light curve shows a fading trend from just after an eclipse until the start of the next eclipse. The brightest flux source in the system is the accretion torus surrounding the mass gainer star, and we argue that these orbital-phase related fadings are the result of the injection of cooler gas from the mass donor entering the outskirts of the accretion torus. There are cyclic variations in the out-of-eclipse sections of the light curve that vary on a 2.8 day timescale. This equals the orbital period for gas in the outer regions of the accretion torus, so the photometric variations are probably the result of transitory, over-dense regions that form at the rim of the accretion torus.
title TESS Light Curve of the Interacting Binary W Serpentis
topic Solar and Stellar Astrophysics
url https://arxiv.org/abs/2504.10608