Vintage NPOI: New and Updated Angular Diameters for 145 Stars

TL;DR

This paper provides new and updated angular diameters, radii, and temperatures for 145 stars using NPOI data, highlighting their potential for habitable planet studies, asteroseismology, and limb-darkening analysis.

Contribution

It offers a comprehensive update on stellar measurements from NPOI, including new data, analysis of data differences over time, and identification of key targets for future research.

Findings

75% of angular diameters have uncertainties of 2% or less

Identified 13 stars as promising habitable world targets

14 stars are suitable for asteroseismic studies

Abstract

We present new or updated angular diameters, physical radii, and effective temperatures for 145 stars from the Navy Precision Optical Interferometer data archive. We used data from 1996 to late-2021, and we describe the differences between early and late data, which hinge upon an update of the beam combiner in 2002. We came across several sub-categories of stars of interest: 13 of our stars are promising targets for the Habitable World Observatory and therefore require as much study as possible, and 14 more are asteroseismic targets and have stellar masses after we combined our radii and effective temperatures with frequencies of maximum oscillation power values from the literature. In addition to this, many of the stars here show measurements to the first null in the visibility curve and beyond, which is the gateway to determining second-order effects such as direct measurements of limb-darkening. Finally, we consider the stars in the larger context of previous NPOI measurements and find the majority 75% of the angular diameters in the overall NPOI sample have uncertainties of 2% or less.