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arXiv · astro-ph/0104225

NLTE Synthetic Spectral Fits to the Type Ia Supernova 1994D in NGC 4526

Eric J. Lentz·E. Baron·David Branch·Peter H. Hauschildt
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Abstract

We have fit the normal, well observed, Type Ia Supernova (SN Ia) SN 1994D with non-LTE spectra of the deflagration model W7. We find that well before maximum luminosity W7 fits the optical spectra of SN 1994D. After maximum brightness the quality of the fits weakens as the spectrum forms in a core rich in iron peak elements. We show the basic structure of W7 is likely to be representative of the typical SN Ia. We have shown that like W7, the typical SN Ia has a layer of unburned C+O composition at v > 15000 \kmps, followed by layers of C-burned and O-burned material with a density structure similar to W7. We present UVOIR (UBVRIJKH) synthetic photometry and colors and compare with observation. We have computed the distance to the host galaxy, NGC 4526, obtaining a distance modulus of μ= 30.8 \pm 0.3. We discuss further application of this direct measurement of SNe Ia distances. We also discuss some simple modifications to W7 that could improve the quality of the fits to the observations.

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Eric J. Lentz, E. Baron, David Branch, Peter H. Hauschildt. 2001-04-12. NLTE Synthetic Spectral Fits to the Type Ia Supernova 1994D in NGC 4526. https://doi.org/10.1086/322239

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