1. THE PECULIAR EXTINCTION LAW OF SN 2014J MEASURED WITH THE HUBBLE SPACE TELESCOPERahman Amanullah, Ariel Goobar, Joel Johansson, D.P.K. Banerjee, V. Venkataraman, V. Joshi, N.M. Ashok, Yi Cao, Mansi Kasliwal, S.R. Kulkarni, P.E. Nugent, Tanja Petrushevska, V. Stanishev, 2014, original scientific article Abstract: The wavelength dependence of the extinction of Type Ia SN 2014J in the nearby galaxy M82 has been measured
using UV to near-IR photometry obtained with the Hubble Space Telescope, the Nordic Optical Telescope, and
the Mount Abu Infrared Telescope. This is the first time that the reddening of an SN Ia is characterized over the
full wavelength range of 0.2–2μm. A total-to-selective extinction, RV 3.1, is ruled out with high significance.
The best fit at maximum using a Galactic type extinction law yields RV = 1.4 ± 0.1. The observed reddening of
SN 2014J is also compatible with a power-law extinction, Aλ/AV = (λ/λV )
p as expected from multiple scattering
of light, with p = −2.1 ± 0.1. After correcting for differences in reddening, SN 2014J appears to be very similar
to SN 2011fe over the 14 broadband filter light curves used in our study. Keywords: dust, extinction – galaxies: individual (Messier 82) – supernovae: individual SN2014J Published in RUNG: 22.01.2018; Views: 5864; Downloads: 0 This document has many files! More... |
2. THE RISE OF SN 2014J IN THE NEARBY GALAXY M82Ariel Goobar, Joel Johansson, Rahman Amanullah, Yi Cao, Mansi Kasliwal, Raphael Ferretti, Peter Nugent, Daniel Perley, Avishay Gal-Yam, Eran Ofek, S. P. Tendulkar, M. Dennefeld, Stefano Valenti, Iair Arcavi, D.P.K. Banerjee, V. Venkataraman, Brad Cenko, Tanja Petrushevska, T.J. Dupuy, M.C. Liu, 2014, original scientific article Abstract: We report on the discovery of SN 2014J in the nearby galaxy M82. Given its proximity, it offers the best opportunity
to date to study a thermonuclear supernova (SN) over a wide range of the electromagnetic spectrum. Optical, nearIR,
and mid-IR observations on the rising light curve, orchestrated by the intermediate Palomar Transient Factory,
show that SN 2014J is a spectroscopically normal Type Ia supernova (SN Ia), albeit exhibiting high-velocity features
in its spectrum and heavily reddened by dust in the host galaxy. Our earliest detections start just hours after the
fitted time of explosion. We use high-resolution optical spectroscopy to analyze the dense intervening material and
do not detect any evolution in the resolved absorption features during the light curve rise. Similar to other highly
reddened SNe Ia, a low value of total-to-selective extinction, RV 2, provides the best match to our observations.
We also study pre-explosion optical and near-IR images from Hubble Space Telescope with special emphasis on
the sources nearest to the SN location. Keywords: dust, extinction – galaxies: individual (Messier 82) – supernovae: individual (SN 2014J) Published in RUNG: 22.01.2018; Views: 4904; Downloads: 0 (1 vote) This document has many files! More... |