The following document lists the file abstract/PABRAHAM_DRA_CIRR.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
==================================================================== As part of the PHT calibration programme, we have observed an area of 10.5'x7.5' around the faint star HR 6132 at 90 um and 175 um. The star is located in the outskirt of the Draco cloud on top of a faint cirrus filament as revealed by IRAS. With the better resolution of ISOPHOT the central part of the filament was resolved into three point-like sources: one is HR 6132 while the other two seem to be cirrus knots. In case they really belong to the cirrus and such so far unidentified structures are frequently detected even in regions of faint cirrus, the detection of faint sources with ISOPHOT would be hampered. Since both the 90 um and 175 um maps are very deep (t(int)=288 s and 512 s per sky position, respectively), the field has already been used for a preliminary analysis of the cirrus confusion noise (Herbstmeier et al. 1997, in preparation). The Draco region is an ideal object because it is a prototype-like cirrus cloud complex with molecular cores and atomic filaments. An extension of the available database is however necessary as observations of the remaining parts of the filament will (i) improve significantly our statistics on confusion noise; (ii) answer whether the whole filament could be resolved in a chain of point sources; (iii) reveal the physical nature of the newly detected point-like sources by observations at various wavelengths. From our experience with the previous maps we can reliably predict all the observational parameters (expected brightness, variation of the background, signal-to-noise).