Hidden Companions to Intermediate-mass Stars. VI. Discovery of a 0.50M ⊙, 6 au Companion to HIP 74696* *Based on observations collected at the European Southern Observatory, Chile, Program ID 111.24UP.001.

Abstract

A-type stars with a large long-term proper motion change and without a known companion to cause it are candidates for being Sirius analogues. However, in most cases the culprit is expected to be a hitherto unknown low mass companion rather than a white dwarf. Here we report the discovery of a 0.50M ⊙ companion to the nearby 1.64M ⊙ star HIP 74696 at a projected separation ρ = 118.9 mas ↔ 6.2 au based on a VLTI/GRAVITY observation. This companion explains the Gaia–Hipparcos proper motion change of the primary. Together with the wide 660 au companion that was found by Gaia DR3 to be a 0.70M ⊙ + 0.20M ⊙ 1.5 au binary, this makes HIP 74696 a quadruple and part of the growing class of high multiplicity systems with an A-type star primary.