Targets:
G34.41+0.2, G23.21-0.3, G327.29-0.6, G34.26+0.2, G351.58-0.4, G35.20-0.7, G5.89-0.4, W33A, W49N, W43MM1, G31.41+0.31
Target Description:
Massive star forming clumps in a range of evolutionary stages
Instrument:
GREAT
Spectral Element:
L2 Channel
Rest Frequency:
1810.38 GHz
Bandwidth:
2.5 GHz
Exposure times:
6 to 24 minutes
Observation dates:
July 2011, and July 2013
Proposal IDs:
82_0016, 01_0174
Program PI:
F. Wyrowski
Publication:
Wyrowski et al. 2016, A&A, 585, 1490
[DOI]
http://dx.doi.org/10.1051/0004-6361/201526361
Technical Note
The instrument was tuned to the NH3 ( 3
2+
- 2
2-
) transition at 1.8 THz, and the line was measured in absorption against bright continuum sources. The continuum levels ranged from 0.74 to 12.82K, and line opacities from 0.3 to 2.2. The high critical density of the transition (10
9
cm
-3
) makes it possible to trace dense gas. The high-resolution spectra (0.007 km/s velocity channel width) were smoothed to 0.5 km/s for the analysis.