The Family of V1311 Ori: a Young Sextuple System or a Minicluster?

Abstract

Abstract A compact bound group of four active M-type dwarfs containing V1311 Ori is identified in the Gaia catalog of nearby stars. Located at a distance of 39 pc, it is likely related to the β Pictoris and 32 Ori moving groups by kinematics, isochronal age, and other indicators of youth (Hα emission, presence of lithium, and fast rotation). The brightest star A is a known close binary, for which a preliminary 80 yr visual-spectroscopic orbit is determined. Star B is resolved here into a 0.″08 pair, and the faintest stars C and D are probably single. Considering the nonhierarchical configuration with projected separations of ∼10 kau, this could be either a young sextuple system or a bound but dynamically unstable minicluster (trapezium) that avoided disruption so far. This pre-main-sequence system bridges the gap between moving groups and wide hierarchies.