Diversity in extinction laws of Type Ia supernovae measured between 0.2 and 2μm

DOI: 
10.1093/mnras/stv1505
Publication date: 
01/11/2015
Main author: 
Amanullah R.
IAA authors: 
Gorosabel J.;Herrero-Illana R.
Authors: 
Amanullah R., Johansson J., Goobar A., Ferretti R., Papadogiannakis S., Petrushevska T., Brown P.J., Cao Y., Contreras C., Dahle H., Elias-Rosa N., Fynbo J.P.U., Gorosabel J., Guaita L., Hangard L., Howell D.A., Hsiao E.Y., Kankare E., Kasliwal M., Leloudas G., Lundqvist P., Mattila S., Nugent P., Phillips M.M., Sandberg A., Stanishev V., Sullivan M., Taddia F., Östlin G., Asadi S., Herrero-Illana R., Jensen J.J., Karhunen K., Lazarevic S., Varenius E., Santos P., Seethapuram Sridhar S., Wallström S.H.J., Wiegert J.
Journal: 
Monthly Notices of the Royal Astronomical Society
Publication type: 
Article
Volume: 
453
Pages: 
3300-3328
Number: 
Abstract: 
We present ultraviolet (UV) observations of six nearby Type Ia supernovae (SNe Ia) obtained with the Hubble Space Telescope, three of which were also observed in the near-IR (NIR) with Wide-Field Camera 3. UV observations with the Swift satellite, as well as ground-based optical and NIR data provide complementary information. The combined data set covers the wavelength range 0.2-2 μm. By also including archival data of SN 2014J, we analyse a sample spanning observed colour excesses up to E(B - V) = 1.4 mag. We study the wavelength-dependent extinction of each individual SN and find a diversity of reddening laws when characterized by the total-to-selective extinction RV. In particular, we note that for the two SNe with E(B - V) ≳ 1 mag, for which the colour excess is dominated by dust extinction, we find RV = 1.4 ± 0.1 and RV = 2.8 ± 0.1. Adding UV photometry reduces the uncertainty of fitted RV by ~50 per cent allowing us to also measure RV of individual low-extinction objects which point to a similar diversity, currently not accounted for in the analyses when SNe Ia are used for studying the expansion history of the Universe. © 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.
Database: 
WOK
SCOPUS
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/2015MNRAS.453.3300A/abstract
ADS Bibcode: 
2015MNRAS.453.3300A
Keywords: 
Circumstellar matter; Dust, extinction; Supernovae: general; Supernovae: individual: 2012cu; Supernovae: individual: SNe 2012cg