We propose to observe the mid-infrared spectra of the general disk em=
ission=20
of two edge-on spirals, NGC891 and NGC5907, and the amorphous starbur=
st
galaxy M82. Raster maps with 32 points are measured along the central=
dust=20
lane of each galaxy. This will give a representative sample of differ=
ent=20
lines of sight through the galactic disks, with the UIR emission band=
s=20
being generated partly in diffuse medium and partly in the UV-enhance=
d=20
star formation areas of the galaxies.
This proposal has been motivated by the results of our on-going ISOPH=
OT-S=20
spectrophotometry of the diffuse emission of the Milky Way disk. The =
results
of the present proposal will be compared with the Milky Way results.
We expect that our study will provide useful information on the
abundance and distribution of the UIR band carriers in
spiral galaxies. Furthermore, this study should provide useful
data also for the interpretation of mid-infrared broad-band photometr=
y
of galaxies, as obtained by IRAS or by ISO.