The following document lists the file abstract/DLEMKE_VERYCOLD.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
Neutral hydrogen 21 cm emission is observed in many late type spiral galaxies to extend far outside the optical disks. In addition, the rotation curves derived from the 21 cm line show in many such cases a constant rotational velocity persisting to large galactocentric radii, indicating the presence of large amounts of dark matter. Besides the massive halo picture, another possible form of dark matter is the very cold gas and dust in the disk of the galaxy. We propose to search for the presence of very cold dust ( <15 K) in the outer parts of the disk of the NGC 5097 spiral galaxy. ISOPHOT has the capability to observe beyond the IRAS long-wave- length limit up to 240 microns and has an unprecedented sensitivi- ty in this waveband. Furthermore, the combination of PHT photometry in three wavebands, 180, 135, and 90 microns, enables us to eliminate the disturbing effects of warmer foreground dust (galactic cirrus) and to estimate the temperature of the very cold dust.