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arXiv · 2309.08215

Intrinsic and extinction colour components in SNeIa and the determination of $R_V$

G. Smadja·Y. Copin·W. Hillebrandt·C. Saunders·C. Tao
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Abstract

The key ingredients in this attempt at separating for each supernova the intrinsic and extinction colour components, and then measuring Rv , are the assumptions of a linearized dependence of magnitudes on the extinction component of colour, a one-dimensional extra-intrinsic colour space (in addition to CaII H&K $\lambda$3945 and Si II $\lambda$4131 contributions, and the absence of correlations between intrinsic and extrinsic variabilities. A consistent solution is found under the previous assumptions, but the observed systematic trends point to a small inadequacy of the extinction formula. Once corrected, all systematic extinction effects can be cancelled by choosing a single scaling of the extinction colour component as well as the appropriate value of Rv = 2.181 $\pm$ 0.117

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G. Smadja, Y. Copin, W. Hillebrandt, C. Saunders, C. Tao. 2023-09-15. Intrinsic and extinction colour components in SNeIa and the determination of $R_V$. https://doi.org/10.1051/0004-6361%2F202245497

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