A Catalog of Near Infrared Spectra from Type Ia Supernovae
  We present forty-one near infrared (NIR, 0.7-2.5 microns) spectra from normal
Type Ia supernovae (SNe Ia) obtained at epochs ranging from fourteen days
before to seventy-five days with respect to the maximum light date in the
V-band. All data were obtained at the IRTF using the SpeX instrument. We
identify many spectral features, measure the Doppler velocities, and discuss
the chemical distribution of explosion products in SNe Ia. We describe
procedures for smoothing data, fitting continua, and measuring absorption
features to insure consistency for measurement and analysis.
  This sample provides the first opportunity to examine and compare a large
number of SNe Ia in this wavelength region. NIR data are a rich source of
information about explosion products whose signatures are blended or obscured
in other spectral regions and NIR observations probe a greater radial depth
than optical wavelengths. We analyze similarities and differences in the
spectra and we show that the progressive development of spectral features for
normal SNe Ia in the NIR is consistent with time.
  Measured Doppler velocities indicate that burning products in SNe Ia are
distributed in distinct layers with no large scale mixing. Carbon is not
detected in these data, in agreement with previous results with NIR data
establishing very low limits on carbon abundance in SNe Ia. Carbon burning
products, O and Mg, are plentiful in the outer layers suggesting that the
entire progenitor is burned in the explosion. The data provide a resource for
investigations of cross-correlations with other data libraries that may further
constrain SN Ia physics and improve the effectiveness of SNe Ia as cosmological
distance indicators.
