SDSSJ1156-0207: A 0.54 M_sun + 0.19 M_sun Double-lined M Dwarf Eclipsing Binary System

TL;DR

This paper reports the discovery and characterization of a faint double-lined M-dwarf eclipsing binary system, SDSSJ1156-0207, using photometric data from the Catalina survey and spectroscopic follow-up from Gemini, providing key stellar parameters.

Contribution

It presents the first detailed measurement of stellar masses and radii for a faint double-lined M-dwarf eclipsing binary using combined photometric and spectroscopic data.

Findings

Both components are M dwarfs with well-constrained masses and radii.

The primary is 0.54 M_sun and 0.46 R_sun; the secondary is 0.19 M_sun and 0.30 R_sun.

Spectroscopic follow-up enables precise stellar parameter determination.

Abstract

Eclipsing binaries are instrumental to our understanding of fundamental stellar parameters. With the arrival of ultra-wide cameras and large area photometric monitoring programs, numerous eclipsing binaries systems have been reported photometrically. However, due to the expensive efforts to follow up them spectroscopically, most of their basic properties remain unexplored. In this paper we exploited the eclipsing binary light curves delivered by the all-sky Catalina sky surveys, in tandem with the single shot spectroscopic survey from SDSS, and identify a double-lined M-dwarf eclipsing binary SDSSJ1156-0207. Because this system is very faint (V=15.89 mag), we obtained follow-up radial velocity measurements using Gemini Multi-Object Spectrograph onboard Gemini north telescope. This provides us a spectral resolution R~4000, enabling us to determine the mass and radius of each stellar components when jointly fitted with light curve. Our best-fit results indicate that both components are of M dwarf, with the primary component to be 0.54+/-0.20 M_sun and 0.46+/-0.08 R_sun, while the secondary component to be 0.19+/-0.08 M_sun and 0.30+/-0.08 R_sun. High resolution spectroscopic observations in the future will help pin down the stellar parameters, providing insights to the stellar models at low mass regimes, as well as shedding lights on the internal structure of close-in low mass objects and their inflation mechanism.