Testing the consistency of dust laws in SN Ia host galaxies: A <scp>BayeSN</scp> Examination of Foundation DR1

We apply BayeSN, our new hierarchical Bayesian model for the SEDs of Type Ia supernovae (SNe Ia), to analyse $griz$ light curves 157 nearby SNe ($0.015<z<0.08$) from public Foundation DR1 dataset. train a version continuous 0.35--0.95 $\mu$m, which we use properties in rest-frame $z$-band, study dust their host galaxies, and construct Hubble diagram SN distances determined full curves. Our has low total RMS 0.13 mag using compared 0.16 SALT2. Additionally, test consistency law $R_V$ between low- high-mass galaxies by fit time- wavelength-dependent up moderate reddening (peak apparent $B-V \lesssim 0.3$). Splitting population at median mass, find $R_V=2.84\pm0.31$ low-mass hosts, $R_V=2.58\pm0.23$ both consistent with global value $R_V=2.61\pm0.21$ that estimate sample. For all choices mass split consider, is across step within $\lesssim1.2\sigma$. Modelling distributions laws subsamples are highly sample's mean $\mu(R_V) = 2.70\pm0.25$ 95% upper bound on $\sigma(R_V) < 0.61$. The means simultaneous fitting host-mass-dependent does not account conventional step.