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arXiv · 0806.3276

GALEX Spectroscopy of SN 2005ay suggests a UV spectral uniformity among type II-P supernovae

A. Gal-Yam·F. Bufano·T. Barlow·E. Baron·S. Benetti·E. Cappellaro·P. J. Challis·R. S. Ellis·A. V. Filippenko·R. J. Foley·D. B. Fox·M. Hicken·R. P. Kirshner·D. C. Leonard·W. Li·D. Maoz·T. Matheson·P. A. Mazzali·M. Modjaz·K. Nomoto·E. O. Ofek·J. Simon·T. Small·G. P. Smith·M. Turatto·S. D. Van Dyk·L. Zampieri
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Abstract

We present the first results from our GALEX program designed to obtain ultraviolet (UV) spectroscopy of nearby core-collapse supernovae (SNe). Our first target, SN 2005ay in the nearby galaxy NGC 3938, is a typical member of the II-P SN subclass. Our spectra show remarkable similarity to those of the prototypical type II-P event SN 1999em, and resemble also Swift observations of the recent type II-P event SN 2005cs. Taken together, the observations of these three events trace the UV spectral evolution of SNe II-P during the first month after explosion, as required in order to interpret optical observations of high-redshift SNe II-P, and to derive cross-filter K-corrections. While still highly preliminary, the apparent UV homogeneity of SNe II-P bodes well for the use of these events as cosmological probes at high redshift.

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A. Gal-Yam, F. Bufano, T. Barlow, E. Baron, S. Benetti, E. Cappellaro, P. J. Challis, R. S. Ellis, A. V. Filippenko, R. J. Foley, D. B. Fox, M. Hicken, R. P. Kirshner, D. C. Leonard, W. Li, D. Maoz, T. Matheson, P. A. Mazzali, M. Modjaz, K. Nomoto, E. O. Ofek, J. Simon, T. Small, G. P. Smith, M. Turatto, S. D. Van Dyk, L. Zampieri. 2008-06-20. GALEX Spectroscopy of SN 2005ay suggests a UV spectral uniformity among type II-P supernovae. https://doi.org/10.1086/592744

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