SIMBAD references

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 0.09pc, hydrogen densities from 0.6x10⁴ to 19.9x10⁴cm^–3 and kinetic temperatures between 7.9 and 9.9K. The masses range from 0.2 and 1.0M_☉, 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 HC₅Ntowards the ammonia peak positions of these four molecular cores. The HC₅N column densities are between 1.6x10¹² and 9.2x10¹²cm^–2, in agreement with values derived for other molecular cores located in the TMC.