Diversity in extinction laws of Type Ia supernovae measured between 0.2 and 2 μm
Journal article, 2015
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.
circumstellar matter
extinction
supernovae: individual: 2012cu
supernovae: general
supernovae: individual: SNe 2012cg
dust
Author
R. Amanullah
Stockholm University
J. Johansson
Stockholm University
A. Goobar
Stockholm University
R. Ferretti
Stockholm University
S. Papadogiannakis
Stockholm University
T. Petrushevska
Stockholm University
P.J. Brown
Texas A&M University
Y. Cao
California Institute of Technology (Caltech)
C. Contreras
Las Campanas Observatory
H. Dahle
University of Oslo
N. Elias-Rosa
Istituto nazionale di astrofisica (INAF)
J.P.U. Fynbo
Niels Bohr Institute
J. Gorosabel
Institute of Astrophysics of Andalusia (IAA)
University of the Basque Country (UPV/EHU)
L. Guaita
Osservatorio Astronomico di Roma
L. Hangard
Stockholm University
D.A. Howell
Las Cumbres Observatory Global Telescope Network
University of California
E.Y. Hsiao
Las Campanas Observatory
Aarhus University
E. Kankare
Queen's University Belfast
M. Kasliwal
Carnegie Observatories
G. Leloudas
Niels Bohr Institute
Weizmann Institute of Science
P. Lundqvist
Stockholm University
S. Mattila
University of Turku
P. Nugent
University of California
Lawrence Berkeley National Laboratory
M.M. Phillips
California Institute of Technology (Caltech)
A. Sandberg
Stockholm University
V. Stanishev
Instituto Superior Tecnico
M. Sullivan
University of Southampton
F. Taddia
Stockholm University
G. Östlin
Stockholm University
S. Asadi
Stockholm University
R. Herrero-Illana
Institute of Astrophysics of Andalusia (IAA)
J.J. Jensen
Niels Bohr Institute
K. Karhunen
Tuorla Observatory
S. Lazarevic
University of Belgrade
Eskil Varenius
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
P. Santos
University of Oslo
S. Seethapuram Sridhar
Netherlands Institute for Radio Astronomy (ASTRON)
University of Groningen
Sofia Wallström
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
Joachim Wiegert
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 453 3 3300-3328Subject Categories
Astronomy, Astrophysics and Cosmology
Roots
Basic sciences
DOI
10.1093/mnras/stv1505