IRAS 15099-5856: Remarkable Mid-Infrared Source with Prominent
  Crystalline Silicate Emission Embedded in the Supernova Remnant MSH15-52
  We report new mid-infrared observations of the remarkable object IRAS
15099-5856 using the space telescopes AKARI and Spitzer, which demonstrate the
presence of prominent crystalline silicate emission in this bright source. IRAS
15099-5856 has a complex morphology with a bright central compact source (IRS1)
surrounded by knots, spurs, and several extended (~4') arc-like filaments. The
source is seen only at >= 10 um. The Spitzer MIR spectrum of IRS1 shows
prominent emission features from Mg-rich crystalline silicates, strong [Ne II]
12.81 um and several other faint ionic lines. We model the MIR spectrum as
thermal emission from dust and compare with the Herbig Be star HD 100546 and
the luminous blue variable R71, which show very similar MIR spectra. Molecular
line observations reveal two molecular clouds around the source, but no
associated dense molecular cores. We suggest that IRS1 is heated by UV
radiation from the adjacent O star Muzzio 10 and that its crystalline silicates
most likely originated in a mass outflow from the progenitor of the supernova
remnant (SNR) MSH 15-52. IRS1, which is embedded in the SNR, could have been
shielded from the SN blast wave if the progenitor was in a close binary system
with Muzzio 10. If MSH15-52 is a remnant of Type Ib/c supernova (SN Ib/c), as
has been previously proposed, this would confirm the binary model for SN Ib/c.
IRS1 and the associated structures may be the relics of massive star death, as
shaped by the supernova explosion, the pulsar wind and the intense ionizing
radiation of the embedded O star.
