STAR-FORMATION IN L-1251 .2. THE NEXT-GENERATION - NH3 CORES

We have mapped the NH3 (1,1) and (2,2) transitions towards the L 1251 dark cloud. Our observations covered an area of 0.12 square degrees sa mpled at intervals of 80('') (2 times the HPBW). We detected eight amm onia cores with typical sizes (at half power) of 2' (0.2pc at 350pc di stance). We estimate that the cores have a maximum H-2 density of orde r 10(5) cm(-3) and average T-kin, of 10 K. Their masses are in the ran ge of 5-34 M(.) and they typically are close to virial equilibrium, By comparison with earlier maps of (CO)-O-18, we estimate the fraction o f the cloud material in the form of dense ( > 10(4) cm(-3)) cores to b e of order 40 percent.