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arXiv · 1510.01702

The Impact of Starspots on Mass and Age Estimates During The Pre-Main Sequence

Garrett Somers·Marc H. Pinsonneault
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Abstract

We investigate the impact of starspots on the evolution of late-type stars during the pre-main sequence (pre-MS). We find that heavy spot coverage increases the radii of stars by 4-10%, consistent with inflation factors in eclipsing binary systems, and suppresses the rate of pre-MS lithium depletion, leading to a dispersion in zero-age MS Li abundance (comparable to observed spreads) if a range of spot properties exist within clusters from 3-10 Myr. This concordance with data implies that spots induce a range of radii at fixed mass during the pre-MS. These spots decrease the luminosity and $T_{\rm eff}$ of stars, leading to a displacement on the HR diagram. This displacement causes isochrone derived masses and ages to be systematically under-estimated, and can lead to the spurious appearance of an age spread in a co-eval population.

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Garrett Somers, Marc H. Pinsonneault. 2015-10-06. The Impact of Starspots on Mass and Age Estimates During The Pre-Main Sequence. https://doi.org/10.1017/s1743921315006092

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