FCRAO 1998-99 Summary, Coherence
Study of TMC-1C
Based on the plots shown below, we can say the
following:
- N2H+ shows the same behavior as NH3 in TMC-1C, which means ions and
neutrals both show "coherence". Non-thermal width implied by
N2H+ is sigma_NT=0.10 km/s (roughly twice the thermal width).
- C34S shows a constant line width, but at a level well above the N2H+
and NH3. Is C34S optically thick, or distributed in a shell (making it
an "early time" molecule)?
- C17O seems consistent with IRAM now, showing a similar slope as well...
note that the C34S width implies that the C34S could be spatially intermixed
with the C17O roughly in a shell with the radius given by the point where
the C17O and C34S widths match.
Still on the "TO-DO" list:
- re-do all fits with hfs program, where applicable
- compare hfs results with Gaussian fits (Results below are all for
Gaussian fits to isolated components.)
- carefully consider optical depth, especially in C17O and C34S
- compare with IRAM data
- use maps to convert T_A scale to "R" scale
- update data file location list link below (Hector?)
Comments are compiled here.
List of data file locations is stored here.
Notes: Click on molecule name for more information
on those data. Click and select "open this image" to enlarge plots
Last updated 2/16/99, by AG