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arXiv · 2508.08845

A new deepening of mass-radius empirical relation for main sequence stars

Salvatore Camposeo
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Abstract

In the following paper I have compared some typical mass-radius relations for main sequence stars by studying their level of agreement with DEBCat [https://doi.org/10.48550/arXiv.1411.1219], which is a recent catalogue by J. Southworth. Models chosen for testing were originally developed using older, smaller datasets than DEBCat. Each model follows a two-piece function structure, where each branch is a monomial power-law. This approach is motivated by theoretical considerations suggesting that low-mass and high-mass main sequence stars exhibit distinct behaviors in energy production and energy transport. Best level of agreement is found for Zamorano's model [https://doi.org/10.1007/bf00653969]. Also a new empirical relation is proposed by fitting a two-piece monomial power-law to DEBCat main sequence stars.

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Salvatore Camposeo. 2025-08-12. A new deepening of mass-radius empirical relation for main sequence stars. https://doi.org/10.1051/emsci%2F2025001

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