Astronomy and Astrophysics – Astronomy
Scientific paper
May 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997apj...480..420p&link_type=abstract
Astrophysical Journal v.480, p.420
Astronomy and Astrophysics
Astronomy
25
Ism: Molecules, Line: Identification, Molecular Data, Molecular Processes, Radio Lines: Ism
Scientific paper
Ethyl alcohol (ethanol) is known to possess a pair of closely spaced excited torsional substates (gauche+, gauche-) at an energy of approximately 57 K above the ground (trans) torsional substate. We report an extended analysis of some gauche- --gauche+ Q-branch ( Delta J = 0) transitions with a three-substate fixed frame axis method (FFAM) Hamiltonian. Our approach accounts for complex trans--gauche interactions for the first time. In addition, we are able to obtain intensities for perturbed rotational transitions, and to determine the trans to gauche+ separation to be 1185399.1 MHz. A complete ground state rotational-torsional partition function accounting for the previously neglected gauche substates is presented. Based on our analysis, a total of 14 U lines obtained towards Orion KL can now be assigned to gauche substates of ethanol. Analysis of these lines yields a rotational temperature of 223 K and a total (trans + gauche) column density of 7.0 x 1015 cm-2. The column density is in reasonable agreement with the recent value of 2--3 x 1015 cm-2 based on observations of trans-ethanol by Ohishi et al., although there is some disparity in the rotational temperatures. Eight additional U lines in the literature are assigned to transitions of gauche ethanol.
de Lucia Frank C.
Herbst Eric
Pearson James C.
Sastry V. L. N. K.
No associations
LandOfFree
Gauche Ethyl Alcohol: Laboratory Assignments and Interstellar Identification does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Gauche Ethyl Alcohol: Laboratory Assignments and Interstellar Identification, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gauche Ethyl Alcohol: Laboratory Assignments and Interstellar Identification will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-835895