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arXiv · 2501.10919

The Baryonic Tully-Fisher Relation II: Stellar Mass Models

Francis Duey·James Schombert·Stacy McGaugh·Federico Lelli
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Abstract

We present new color-$\Upsilon_*$ (mass-to-light) models to convert WISE W1 fluxes into stellar masses. We outline a range of possible star formation histories and chemical evolution scenarios to explore the confidence limits of stellar population models on the value of $\Upsilon_*$. We conclude that the greatest uncertainties (around 0.1 dex in $\Upsilon_*$) occur for the bluest galaxies with the strongest variation in recent star formation. For high mass galaxies, the greatest uncertainty arises from the proper treatment of bulge/disk separation in which to apply different $\Upsilon_*$ relations appropriate for those differing underlying stellar populations. We compare our deduced stellar masses with those deduced from {\it Spitzer} 3.6$\mu$m fluxes and stellar mass estimates in the literature using optical photometry and different $\Upsilon_*$ modeling. We find the correspondence to be excellent, arguing that rest-frame near-IR photometry is still more advantageous than other wavelengths.

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Francis Duey, James Schombert, Stacy McGaugh, Federico Lelli. 2025-01-19. The Baryonic Tully-Fisher Relation II: Stellar Mass Models. https://arxiv.org/abs/2501.10919

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