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In this second paper in a series we present measurements of spectral features of 432 low-redshift (z < 0.1) optical spectra of 261 Type Ia supernovae (SNe Ia) within 20 d of maximum brightness. The data were obtained from 1989 through the end of 2008 as part of the Berkeley SN Ia Program (BSNIP) and are presented in BSNIP I (Silverman et al. 2012). We describe in detail our method of automated, robust spectral feature definition and measurement which expands upon similar previous studies. Using this procedure, we attempt to measure expansion velocities, pseudo-equivalent widths (pEW), spectral feature depths, and fluxes at the centre and endpoints of each of nine major spectral feature complexes. We investigate how velocity and pEW evolve with time and how they correlate with each other. Various spectral classification schemes are employed and quantitative spectral differences among the subclasses are investigated. Several ratios of pEW values are calculated and studied. The so-called Si II ratio, often used as a luminosity indicator (Nugent et al. 1995), is found to be well correlated with the so-called SiFe ratio and anticorrelated with the analogous SSi ratio, confirming the results of previous studies. Furthermore, SNe Ia that show strong evidence for interaction with circumstellar material or an aspherical explosion are found to have the largest near-maximum expansion velocities and pEWs, possibly linking extreme values of spectral observables with specific progenitor or explosion scenarios. [Abridged]
In this third paper in a series we compare spectral feature measurements to photometric properties of 108 low-redshift (z < 0.1) Type Ia supernovae (SNe Ia) with optical spectra within 5 d of maximum brightness. We find the pseudo-equivalent width (p
In this work we analyse late-time (t > 100 d) optical spectra of low-redshift (z < 0.1) Type Ia supernovae (SNe Ia) which come mostly from the Berkeley Supernova Ia Program dataset. We also present spectra of SN 2011by for the first time. The BSNIP s
We present 637 low-redshift optical spectra collected by the Berkeley Supernova Ia Program (BSNIP) between 2009 and 2018, almost entirely with the Kast double spectrograph on the Shane 3~m telescope at Lick Observatory. We describe our automated spec
In this first paper in a series we present 1298 low-redshift (zleq0.2) optical spectra of 582 Type Ia supernovae (SNe Ia) observed from 1989 through 2008 as part of the Berkeley SN Ia Program (BSNIP). 584 spectra of 199 SNe Ia have well-calibrated li
We present the first maximum-light ultraviolet (UV) through near-infrared (NIR) Type Ia supernova (SN Ia) spectrum. This spectrum of SN 2011iv was obtained nearly simultaneously by the Hubble Space Telescope at UV/optical wavelengths and the Magellan