Photometric and spectroscopic observations, and abundance tomography modelling of the Type Ia supernova SN 2014J located in M82

Abstract

Spectroscopic and photometric observations of the nearby Type Ia Supernova (SN Ia) SN 2014J are presented. Spectroscopic observations were taken −8 to +10 d relative to Bband maximum, using FRODOSpec, a multipurpose integral-field unit spectrograph. The observations range from 3900 to 9000 Å. SN 2014J is located in M82 which makes it the closest SN Ia studied in at least the last 28 yr. It is a spectroscopically normal SN Ia with high-velocity features.Wemodel the spectra of SN 2014J with a Monte Carlo radiative transfer code, using the abundance tomography technique. SN 2014J is highly reddened, with a host galaxy extinction of E(B − V) = 1.2 (RV = 1.38). It has a �m15(B) of 1.08 ± 0.03 when corrected for extinction. As SN 2014J is a normal SN Ia, the density structure of the classical W7 model was selected. The model and photometric luminosities are both consistent with B-band maximum occurring on JD 245 6690.4 ± 0.12. The abundance of the SN 2014J behaves like other normal SN Ia, with significant amounts of silicon (12 per cent by mass)and sulphur (9 per cent by mass) at high velocities (12 300 km s−1) and the low-velocity ejecta (v < 6500 km s−1) consists almost entirely of 56Ni. Key words: radiative transfer – techniques: spectroscopic – supernovae: general – supernovae: individual: SN 2014J