Observations of Hierarchical Solar-Type Multiple Star Systems

TL;DR

This study used high-resolution adaptive optics imaging to observe and confirm the hierarchical structure of 20 solar-type multiple star systems, discovering five new close sub-systems and providing detailed analysis of their properties.

Contribution

It provides new near-infrared observations confirming and expanding the known multiplicity of solar-type stars, including first-time resolution of several close sub-systems.

Findings

Confirmed physical status of most new pairs.

Resolved five close sub-systems for the first time.

Placed components on a color-magnitude diagram for analysis.

Abstract

Twenty multiple stellar systems with solar-type primaries were observed at high angular resolution using the PALM-3000 adaptive optics system at the 5 m Hale telescope. The goal was to complement the knowledge of hierarchical multiplicity in the solar neighborhood by confirming recent discoveries by the visible Robo-AO system with new near-infrared observations with PALM-3000. The physical status of most, but not all, of the new pairs is confirmed by photometry in the Ks band and new positional measurements. In addition, we resolved for the first time five close sub-systems: the known astrometric binary in HIP 17129AB, companions to the primaries of HIP 33555, and HIP 118213, and the companions to the secondaries in HIP 25300 and HIP 101430. We place the components on a color-magnitude diagram and discuss each multiple system individually.