J/A+A/626/A34 SO2 and N-ethylformamide lines (Cernicharo+, 2019)
Broad-band high-resolution rotational spectroscopy for laboratory astrophysics.
Cernicharo J., Gallego J.D., Lopez-Perez J.A., Tercero F., Tanarro I.,
Beltran F., de Vicente P., Lauwaet K., Aleman B., Moreno E., Herrero V.J.,
Domenech J.L., Ramirez S.I., Bermudez C., Pelaez R.J., Patino-Esteban M.,
Lopez-Fernandez I., Garcia-Alvaro S., Garcia-Carreno P., Cabezas C.,
Malo I., Amils R., Sobrado J., Diez-Gonzalez C., Hernandez J.M., Tercero B.,
Santoro G., Martinez L., Castellanos M., Vaquero Jimenez B., Pardo J.R.,
Barbas L., Lopez-Fernandez J.A., Aja B., Leuther A., Martin-Gago J.A.
<Astron. Astrophys. 626, A34 (2019)>
=2019A&A...626A..34C 2019A&A...626A..34C (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: molecular data - molecular processes - line: identification -
plasmas - methods: laboratory: molecular
Abstract:
We present a new experimental set-up devoted to the study of gas phase
molecules and processes using broadband high spectral resolution
rotational spectroscopy. A reactor chamber is equipped with radio
receivers similar to those used by radio astronomers to search for
molecular emission in space. The whole range of the Q (31.5-50GHz)
and W bands (72-116.5GHz) is available for rotational spectroscopy
observations. The receivers are equipped with 16x2.5GHz fast
Fourier transform spectrometers with a spectral resolution of 38.14
kHz allowing the simultaneous observation of the complete Q band and
one-third of the W band. The whole W band can be observed in three
settings in which the Q band is always observed.
Species such as CH3CN, OCS, and SO2 are detected, together with
many of their isotopologues and vibrationally excited states, in very
short observing times. The system permits automatic overnight
observations, and integration times as long as 2.4x105 seconds have
been reached.
The chamber is equipped with a radiofrequency source to produce cold
plasmas, and with four ultraviolet lamps to study photochemical
processes. Plasmas of CH4, N2, CH3CN, NH3, O2, and H2,
among other species, have been generated and the molecular products
easily identified by the rotational spectrum, and via mass
spectrometry and optical spectroscopy.
Finally, the rotational spectrum of the lowest energy conformer of
CH3CH2NHCHO (N-ethylformamide), a molecule previously
characterized in microwave rotational spectroscopy, has been measured
up to 116.5GHz, allowing the accurate determination of its rotational
and distortion constants and its search in space.
Description:
A SO2 line list of some of the performed experiments and the
observed lines of the ground state of NEFA (CH3CH2NHCHO) are
given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 79 288 Meassured frequencies for SO2 species
tablec2.dat 80 616 Identified rotational lines of N-ethylformamide
(CH3CH2NHCHO)
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Mol Molecular species
10- 11 I2 --- J' Quantum number J for upper level
13- 14 I2 --- Ka' Quantum number Ka for upper level
16- 17 I2 --- Kc' Quantum number Kc for upper level
19- 20 I2 --- J" Quantum number J for lower level
22- 23 I2 --- Ka" Quantum number Ka for lower level
25- 26 I2 --- Kc" Quantum number Kc for lower level
28- 37 F10.3 MHz Freq Observed Frequency
39- 43 F5.3 MHz e_Freq Uncertainty associated to frequency
45- 50 F6.3 MHz O-C ? Difference observed - catalogs(CDMS,JPL,MADEX)
52- 58 F7.1 mK TB Line peak intensity derived from the fit
60- 63 F4.1 mK sigma Noise of the data
65- 70 F6.1 mK.MHz W Integred intensity of the line
72 I1 mK.MHz e_W ? Uncertainty of W
74- 76 I3 kHz LW Line width at half intensity
78- 79 I2 kHz e_LW Uncertainty of LW
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Byte-by-byte Description of file: tablec2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- J' Quantum number J for upper level
6- 7 I2 --- Ka' Quantum number Ka for upper level
11- 12 I2 --- Kc' Quantum number Kc for upper level
16- 17 I2 --- J" Quantum number J for lower level
21- 22 I2 --- Ka" Quantum number Ka for lower level
26- 27 I2 --- Kc" Quantum number Kc for lower level
33- 42 F10.3 MHz FreqO Measured frequency
48- 52 F5.3 MHz e_FreqO Uncertainty associated to frequency
59- 68 F10.3 MHz FreqC Calculated frequency
73- 78 F6.3 MHz O-C Difference between calculated & observed
frequency
80 A1 --- Code [ABCD] Code (1)
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Note (1): Code as follows:
A = 1.5{DELTA}νobs<ν(O-C)≤2.0{DELTA}νobs
B = 2.0{DELTA}νobs<ν(O-C)≤2.5{DELTA}νobs
C = 2.5{DELTA}νobs<ν(O-C)≤3.0{DELTA}νobs
D = Unresolved doublet
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Acknowledgements:
Jose Cernicharo, jose.cernicharo(at)csic.es
(End) Patricia Vannier [CDS] 29-May-2019