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arXiv · 2401.11007

A dust attenuation model inspired by the NIHAO-SKIRT-Catalog

Nicholas Faucher·Michael R. Blanton
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Abstract

We use simulated attenuation curves from the NIHAO-SKIRT-Catalog to test the flexibility of commonly used dust attenuation models in the face of the variations expected from realistic star-dust geometries. Motivated by lack of flexibility in these existing models, we propose a novel dust attenuation model with three free parameters that can accurately recover the simulated attenuation curves as well as the best-fitting curves from the commonly used models. This new model is fully analytic and treats all starlight equally, in contrast to two-component dust attenuation models. We use the parametrization to investigate the relationship between the overall attenuation law shape and the strength of the 2175 Å bump. Our results indicate variation in star-dust geometry leads these features to correlate tightly, with grayer attenuation curves having weaker bumps.

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Nicholas Faucher, Michael R. Blanton. 2024-01-19. A dust attenuation model inspired by the NIHAO-SKIRT-Catalog. https://arxiv.org/abs/2401.11007

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