J/ApJ/500/1059 Dimethyl ether transitions frequencies (Groner+, 1998)
Dimethyl ether: laboratory assignments and predictions through 600 GHz.
Groner P., Albert S., Herbst E., De Lucia F.C.
<Astrophys. J. 500, 1059 (1998)>
=1998ApJ...500.1059G 1998ApJ...500.1059G (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Atomic physics
Keywords: ISM: molecules - molecular data - molecular processes -
radio lines: ISM
Abstract:
Dimethyl ether (CH3OCH3) is a well-known interstellar molecule
with a large abundance in hot core regions. We have measured many
rotational-torsional transition lines of this molecule in the
100-550GHz frequency range using two experimental techniques: a
klystron-based traditional millimeter-wave spectrometer and a new fast
scan spectrometer (designated "FASSST") with a voltage-tunable
backward wave oscillator. The lines arising from the ground
vibrational state have been combined with previous data, mainly at
lower frequencies, to form a global data set consisting of over 1600
lines that have been assigned and fitted by an effective Hamiltonian
method. The spectral constants obtained from the fit allow us to
predict the frequencies of almost 6000 additional lines of dimethyl
ether through 600GHz.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 47 2148 Assigned and Fitted Transition Frequencies of
Dimethyl Ether in the Ground Vibrational State
table3.dat 57 7546 Predicted Transition Frequencies of Dimethyl
Ether in the Ground Vibrational State
--------------------------------------------------------------------------------
See also:
J/ApJ/499/517 : Ethylene oxide spectrum (Pan+, 1998)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- t Torsional substates (1)
4- 5 I2 --- J' J' rotational quantum number
7- 8 I2 --- K'a K'a rotational quantum number
10- 11 I2 --- K'c K'c rotational quantum number
13- 14 I2 --- J" J" rotational quantum number
16- 17 I2 --- K"a K"a rotational quantum number
19- 20 I2 --- K"c K"c rotational quantum number
22- 31 F10.3 MHz Freq Frequency
33- 38 F6.3 MHz O-C Observed minus calculated frequency
40- 44 F5.3 MHz e_Freq ?=0.000 rms uncertainty on Freq (2)
46 A1 --- Source Source (3)
--------------------------------------------------------------------------------
Note (1): 00=AA , 01=EE , 11=AE , 12=EA
Note (2): A 0.000 in the uncertainties column signifies that the transition has
been assigned but not included in the fit. Many of these are weaker,
blended lines for which the measured frequency of the stronger
neighbor was used to calculate the listed O - C. A total of 1626
assigned frequencies were used in the fit.
Note (3): L: Lovas et al. 1979, J. Phys. Chem. Ref. Data 8, 1051
D: Durig et al. 1976, J. Molec. Spectrosc. 62, 159
N: Neustock et al. 1990, Z. Naturforsch. 45a, 702
K: this work, klystron-based measurements
F: this work, FASSST-based measurements
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- t Torsional substates (1)
4- 5 I2 --- J' J' rotational quantum number
7- 8 I2 --- K'a K'a rotational quantum number
10- 11 I2 --- K'c K'c rotational quantum number
13- 14 I2 --- J" J" rotational quantum number
16- 17 I2 --- K"a K"a rotational quantum number
19- 20 I2 --- K"c K"c rotational quantum number
22- 31 F10.3 MHz Freq Frequency
33- 37 F5.3 MHz e_Freq rms uncertainty on Freq
39- 40 I2 --- WSpin Spin weight
42- 49 F8.5 --- S S value (Townes & Schawlow, 1975, Microwave
Spectroscopy (New York: Dover)))
51- 57 F7.3 cm-1 Eu Upper state energies
--------------------------------------------------------------------------------
Note (1): Torsional substates: 00=AA , 01=EE , 11=AE , 12=EA
--------------------------------------------------------------------------------
History: From ApJ electronic version
(End) James Marcout, Patricia Bauer [CDS] 09-Mar-1999