PTPS Candidate Exoplanet Host Star Radii Determination with CHARA Array

TL;DR

This paper proposes using the CHARA Array to directly measure the radii of PTPS exoplanet host stars, improving the accuracy of stellar and planetary parameter estimates over spectroscopic methods.

Contribution

It introduces a method to directly determine stellar radii for PTPS candidates, reducing uncertainties caused by spectroscopic and evolutionary model estimates.

Findings

Direct radius measurements improve stellar luminosity estimates.

Enhanced stellar parameters lead to more accurate exoplanet mass calculations.

Method reduces reliance on uncertain evolutionary models.

Abstract

We propose to measure the radii of the Penn State - Torun Planet Search (PTPS) exoplanet host star candidates using the CHARA Array. Stellar radii estimated from spectroscopic analysis are usually inaccurate due to indirect nature of the method and strong evolutionary model dependency. Also the so-called degeneracy of stellar evolutionary tracks due to convergence of many tracks in the giant branch decreases the precision of such estimates. However, the radius of a star is a critical parameter for the calculation of stellar luminosity and mass, which are often not well known especially for giants. With well determined effective temperature (from spectroscopy) and radius the luminosity may be calculated precisely. In turn also stellar mass may be estimated much more precisely. Therefore, direct radii measurements increase precision in the determination of planetary candidates masses and the surface temperatures of the planets.