The evolution of Red Supergiants to supernova in the LMC cluster NGC
  2100
  The mass loss rates of red supergiants (RSGs) govern their evolution towards
supernova and dictate the appearance of the resulting explosion. To study how
mass-loss rates change with evolution we measure the mass-loss rates (\mdot)
and extinctions of 19 red supergiants in the young massive cluster NGC2100 in
the Large Magellanic Cloud. By targeting stars in a coeval cluster we can study
the mass-loss rate evolution whilst keeping the variables of mass and
metallicity fixed. Mass-loss rates were determined by fitting DUSTY models to
mid-IR photometry from WISE and Spitzer/IRAC. We find that the \mdot\ in red
supergiants increases as the star evolves, and is well described by \mdot\
prescription of de Jager, used widely in stellar evolution calculations. We
find the extinction caused by the warm dust is negligible, meaning the warm
circumstellar material of the inner wind cannot explain the higher levels of
extinction found in the RSGs compared to other cluster stars. We discuss the
implications of this work in terms of supernova progenitors and stellar
evolution theory. We argue there is little justification for substantially
increasing the \mdot\ during the RSG phase, as has been suggested recently in
order to explain the absence of high mass Type IIP supernova progenitors. We
also argue that an increase in reddening towards the end of the RSG phase, as
observed for the two most evolved cluster stars, may provide a solution to the
red supergiant problem.
