M. J. F. Rosenberg, P. P. van der Werf, F. P. Israel
Supernovae play an integral role in the feedback of processed material into
the ISM of galaxies and are responsible for much of the chemical enrichment of
the universe. The rate of supernovae can also reveal the star formation
histories. Supernova rates are usually measured through the non-thermal radio
continuum luminosity; however, a correlation between near-infrared [FeII]
emission and supernova remnants has also been noted. We aim to find a
quantitative relationship between the [FeII] at 1.26 um ([FeII]$_{1.26}$)
luminosity and supernova rate in a sample of 11 near-by starburst galaxy
centers. We perform a pixel-pixel analysis of this correlation on SINFONI data
cubes. Using Br$\gamma$ equivalent width and luminosity as the only
observational inputs into the Starburst 99 model, we derive the supernova rate
at each pixel and thus create maps of supernova rates. We then compare these
morphologically and quantitatively to the [FeII]$_{1.26}$ luminosity. We have
found that a strong linear and morphological correlation exists between
supernova rate and [FeII]$_{1.26}$ on a pixel-pixel basis:
\[ log\frac{\nu_{SNrate}}{yr^{-1}pc^{-2}} = 1.01 \pm 0.2\ast
log\frac{[FeII]_{1.26}}{erg s^{-1}pc^{-2}} - 41.17 \pm 0.9\]
This relation is valid for normal star forming galaxies but breaks down for
extreme ultra luminous galaxies. The supernova rates derived from the Starburst
99 model are in good agreement with the radio-derived supernova rates, which
underlines the strength of using [FeII] emission as a tracer of supernova rate.
With the strong correlation found in this sample of galaxies, we conclude that
[FeII]$_{1.26}$ emission can be generally used to derive accurate supernova
rates on either a pixel-pixel or integrated galactic basis.
View original:
http://arxiv.org/abs/1202.2713
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