Four dense molecular cores in the Taurus Molecular Cloud (TMC). Ammonia and cyanodiacetylene observations.
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 0.6x10^4^ to 19.9x10^4^cm^-3^ and kinetic temperatures between 7.9 and 9.9K. The masses range from 0.2 and 1.0Msun_, 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 HC_5_Ntowards the ammonia peak positions of these four molecular cores. The HC_5_N column densities are between 1.6x10^12^ and 9.2x10^12^cm^-2^, in agreement with values derived for other molecular cores located in the TMC.
Astronomy and Astrophysics
- Pub Date:
- August 1997
- ISM: CLOUDS;
- ISM: MOLECULES;
- RADIO LINES: ISM;
- ISM: INDIVIDUAL OBJECTS: TMC;
- 10 pages, Latex file, 7 Postscript Figures, l-aa.sty and psfig.sty included. Accepted to Astronomy and Astrophysics