The following document lists the file abstract/RTUFFS_ENDDISK.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
We propose to map the extended neutral disks of the nuclear starburst spiral NGC 6946 and the edge-on spiral NGC 891 at 175 and 200 microns. These extended HI disks extend about a factor of two beyond the optical disk. The observations will probe the dust content and ambient radiation field in the extended neutral disks. In the event that there is no ambient heating in the extended HI disks, any grains there will still be heated to ca 9 and 13 K by the inner disk luminosity of NGC 891 and NGC 6946, respectively. In this case, the PHT-C detection limit at 200 microns is sufficient to detect grains with a dust-to-HI mass ratio of 0.1 at the outermost parts of the HI disk. The results may throw light on the evolutionary history of the extended HI disks, in particular whether they are predominently primordial in nature, or whether they result from a sporadic accretion of gas from interaction-accretion events over the age of the galaxy.