The pre-cataclysmic variable, LTT560

TL;DR

This study characterizes the binary system LTT560, revealing its components, orbital parameters, and activity, to better understand its evolutionary status as a pre-cataclysmic variable.

Contribution

The paper provides detailed system parameters of LTT560, including component temperatures, mass ratio, and activity indicators, using combined photometric and spectroscopic observations.

Findings

LTT560 consists of a 7500K white dwarf and an M5.5 main-sequence star.

Orbital period is approximately 3.54 hours.

System shows activity likely due to flaring or accretion.

Abstract

System parameters of the object LTT560 are determined in order to clarify its nature and evolutionary status. We apply time-series photometry to reveal orbital modulations of the light curve, time-series spectroscopy to measure radial velocities of features from both the primary and the secondary star, and flux-calibrated spectroscopy to derive temperatures of both components. We find that LTT560 is composed of a low temperature T~7500K DA white dwarf as the primary and an M5.5+-1 main-sequence star as the secondary component. The current orbital period is Porb=3.54(07)h. We derive a mass ratio Msec/Mwd = 0.36(03) and estimate the distance to d=25-40pc. Long-term variation of the orbital light curve and an additional H-alpha emission component on the white dwarf indicate activity in the system, probably in the form of flaring and/or accretion events.