Abstract
Trying to obtain a more complete picture of star forming regions in the Taurus molecular cloud, four dense molecular cores (L1521D, L1521F, L1524, L1507A) are identified and mapped through the ammonia (J,K)= (1,1) and (2,2) rotational inversion lines. These cores have sizes from 0.06 to 0.09 pc, hydrogen densities from 0.6 10(4) to 19.9 10(4) cm(-3) and kinetic temperatures between 7.9 and 9.9 K. The masses range from 0.2 and 1.0 M., placing the cores with the lowest M values at the lower edge of the mass distribution for ammonia cores in the TMC. Turbulent, thermal and gravitational energies have been estimated. A comparison between these energy terms and considerations related to thermal and turbulent line broadening indicate that these cores are close to gravitational equilibrium. Moreover, we report detections of the J=9-8 transition of HC5N towards the ammonia peak positions of these four molecular cores. The HC5N column densities are between 1.6 10(12) and 9.2 10(12) cm(-2), in agreement with values derived for other molecular cores located in the TMC.