AAS Meeting #193 - Austin, Texas, January 1999
Session 71. Molecular Clouds
Display, Friday, January 8, 1999, 9:20am-6:30pm, Exhibit Hall 1

[Previous] | [Session 71] | [Next]

[71.07] Detection and Evolution of Complex Hydrocarbons in TMC

T. Velusamy, W.D. Langer (JPL(Caltech))

The cold, dark cloud cores are the important sites to probe the interstellar chemistry prevailing prior to the onset of collapse. TMC1 is an ideal object to study the chemistry in dark clouds under quiescent conditions. It shows a carbon rich chemistry with chemical gradients across its densest ridge extending over 0.2 pc \times 0.6 pc. We present the results of the DSN 70m observations of complex carbon chain mol ecules (cumelene carbenes H2Cn, radicals CnH, cyanopolyynes HC2n+1N, cumulene rings CnH2) at a few locations (CCS, cyanopolyyne, ammonia and SO peaks) along TMC1 ridge. We report the first detection of C8H in TMC. Large differences are seen in t he intensity ratios among these molecules at different velocities as well as po sitions. Our results indicate differences in the chemical evolutionary statu s among the clumps in the TMC1 ridge. This can be interpreted in terms of a de nsity and time dependent chemical models for the formation and evolution of co mplex molecules.

This research was conducted at the Jet Propulsion Laboratory, California Institute of Technology under support from the National Aeronautics and Space Administration.

[Previous] | [Session 71] | [Next]