INFRARED CARBON STARS - NEW IDENTIFICATIONS AND THEIR SPACE DISTRIBUTION IN THE GALAXY

We present JHKL photometry of a sample of 150 IRAS stars in the third and fourth galactic quadrant with lbl <2 degrees selected according to their IRAS colour (0.160 less than or equal to[12-25]less than or equ al to 1.156). We identify 27 carbon star candidates using the [12-25] vs. K-L two-colour diagram method. Among them, 10 are listed in the St ephenson's catalogue of carbon stars and 17 are new infrared carbon st ars (IRCS) candidates. Their distances are found to be larger than 3 k pc. These data are combined with previous data to study the space dist ribution of IRCS. The number density seems to be independent of the ga lactocentric distance (R) toward the Galactic Center and to decrease e xponentially toward the anticenter. At the present stage, it is not po ssible to disentangle effects such as incompleteness of the sample, di fferent space distribution law and dependence of the luminosity on met allicity. In particular, we suggest that the apparent scarcity of IRCS in the central direction of the Galaxy (R<5 kpc) might be due to a se lection effect. From the available data, we have found no IRCS within 1 kpc of the Galactic Center.