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arXiv · 2505.23514

Thirty-Three New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble

Ellyn K. Baines·James H. Clark III·Henrique R. Schmitt·Jordan M. Stone·Kaspar von Braun
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Abstract

We present new angular diameter measurements for 33 stars from the Navy Precision Optical Interferometer, reaching uncertainties on the limb-darkened diameter of 2% or less for 21 targets. We also determined the physical radius, bolometric flux, luminosity, and effective temperature for each star. Our sample is a mix of giant, subgiant, and dwarf stars, and span spectral classes from mid-A to to mid-K. We combined these 33 stars with samples from previous publications to analyze how the NPOI diameters compare to those obtained using other means, namely (V-K) color, the JMMC Stellar Diameters Catalog, and Gaia predictions.

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Ellyn K. Baines, James H. Clark III, Henrique R. Schmitt, Jordan M. Stone, Kaspar von Braun. 2025-05-29. Thirty-Three New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble. https://doi.org/10.3847/1538-3881%2Fad08be

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