Hubble Space Telescope Imaging and Spectroscopy of the Sirius-Like Triple Star System HD 217411

TL;DR

This study uses Hubble Space Telescope imaging and spectroscopy to analyze the complex triple star system HD 217411, revealing detailed stellar components, their interactions, and evolutionary implications.

Contribution

First detailed imaging and spectroscopic analysis of the HD 217411 triple system, identifying its components and their interactions with implications for stellar evolution.

Findings

HD 217411 is a triple system with a G3 V primary, a K0 V star, and a hot DA white dwarf.

The white dwarf dominates UV flux, while the K0 V star dominates beyond 3000 Å.

Evidence suggests wind-induced spin-up of the K0 V star during the white dwarf's AGB phase.

Abstract

We present Hubble Space Telescope imaging and spectroscopy of HD 217411, a G3 V star associated with the extreme ultraviolet excess source (EUV 2RE J2300-07.0). This star is revealed to be a triple system with a G 3V primary (HD 217411 A) separated by ~1.1" from a secondary that is in turn composed of an unresolved K0 V star (HD 217411 Ba) and a hot DA white dwarf (HD 217411 Bb). The hot white dwarf dominates the UV flux of the system. However; it is in turn dominated by the K0 V component beyond 3000 {\AA}. A revised distance of 143 pc is estimated for the system. A low level photometric modulation having a period of 0.61 days has also been observed in this system along with a rotational velocity on the order of 60 km s-1 in the K0 V star. Together both observations point to a possible wind induced spin up of the K0 V star during the AGB phase of the white dwarf. The nature of all three components is discussed as are constraints on the orbits, system age and evolution.