Co Distributions towards the Southern Dark Cloud of DC 303.6+0.9

Abstract

AbstractDark clouds in the southern skies have been observed with CO J = 1-0 line. The mm-wave telescope of 4-m diameter was used. The beam width was 2’.7 at 2.6 mm wavelength and beam efficiency 0.52. The authors have developed a high-resolution acousto-optical spectrograph with a velocity resolution of 0.07 kms-1 for this purpose. The 115.27 GHz line was detected over an area of 27’ x 21’ including the dark cloud of DC 303.6+0.9 in Crux. Most of the positions, out of a total number of 63, show a double peak line structure. Some positions also show red and blue shifted wings. An average profile shows a higher peak at the radial velocity of -2.8 kms-1 with a calibrated radiation temperature of 5.5 K, a half line width of 1.5 kms-1, and another peak in relative red at a velocity of -0.8 kms-1 with a temperature of 4.3 K, a half line widh of 1.0 kms-1. Profiles distributed over this area show a bipolar diagram. It hints that a certain systematic motions may exist in this region.