AKARI Detection of Far-Infrared Dust Emission in the Halo of NGC253
  We present new far-infrared (FIR) images of the edge-on starburst galaxy
NGC253 obtained with the Far-Infrared Surveyor (FIS) onboard AKARI at
wavelengths of 90 um and 140 um. We have clearly detected FIR dust emission
extended in the halo of the galaxy; there are two filamentary emission
structures extending from the galactic disk up to 9 kpc in the northern and 6
kpc in the northwestern direction. From its spatial coincidence with the X-ray
plasma outflow, the extended FIR emission is very likely to represent
outflowing dust entrained by superwinds. The ratios of surface brightness at 90
um to that at 140 um suggest that the temperatures of the dust in the halo are
getting higher in the regions far from the disk, implying that there exist
extra dust heating sources in the halo of the galaxy.
