Supernova 2014J at M82 – II. Direct analysis of a middle-class Type Ia supernova

摘要: We analyze a time series of optical spectra SN 2014J from almost two weeks prior to maximum nearly four months after maximum. perform our analysis using the SYNOW code, which is well suited track distribution ions with velocity in ejecta. show that all spectral features during entire epoch can be identified permitted transitions common found normal SNe Ia agreement previous studies. relatively Ia. At early times are dominated by Si II, S Mg and Ca II. These persist light appearance Na I I. later iron-group elements also appear, as expected stratified abundance model formation type SNe. do not find significant spectroscopic evidence for oxygen, until 100 days light. The +100 day identification oxygen tentative, would imply mixing unburned or only slight processed down 6,000 km~s−1. Our results good other analyses IR. briefly compare 2011fe conclude differences could due different central densities at ignition C/O ratio progenitors.