J/A+A/544/A19 CH2NH accurate rotational rest frequencies (Dore+, 2012)
Accurate rotational rest frequencies of CH2NH at submillimetre wavelengths.
Dore L., Bizzocchi L., Degli Esposti C.
<Astron. Astrophys. 544, A19 (2012)>
=2012A&A...544A..19D 2012A&A...544A..19D
ADC_Keywords: Atomic physics ; Spectroscopy
Keywords: molecular data - methods: laboratory - techniques: spectroscopic -
radio lines: ISM
Abstract:
Methanimine (CH2NH) has been detected in different astronomical
sources, both galactic (as in several "hot cores", the circumstellar
enevolope IRC+10216, and the L183 pre-stellar core) and extragalactic,
and is considered a pre-biotic interstellar molecule. Its ground-state
rotational spectrum has been studied in the laboratory up to 172GHz,
well below the spectral ranges covered by Herschel/HIFI and the ALMA
bands 9 and 10.
In this laboratory study, we extend into the submillimetre-wave region
the detection of the rotational spectrum of CH2NH in its vibrational
ground state.
Description:
Table 1 lists the transition frequencies of methanimine measured in
laboratory along with their estimated uncertainties and the residuals
from a weighted fit using Watson's S-reduced Ir representation. The
last 84 records report the newly observed transitions recorded by
means of a submillimetre-wave spectrometer, the other observations are
from Dore et al. (2010JMoSp.263...44D 2010JMoSp.263...44D).
Table 3 is an expansion of the article's Table3 reporting rest
frequencies and line strengths of the strongest transitions at 50K in
the region 0.4-1THz
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 60 210 Observed hyperfine frequencies and residuals
of CH2NH
table3.dat 48 314 Calculated hyperfine frequencies of CH2NH
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See also:
J/A+A/425/767 : HC5N vibrationally excited states (Yamada+, 2004)
J/A+A/413/1177 : Spectroscopy of N2D+ hyperfine structure (Dore+, 2004)
J/A+A/455/1161 : Rest frequencies of sub-mm spectrum of SiN (Bizzocchi+, 2006)
J/A+A/492/875 : Rest frequencies for C3O (Bizzocchi+, 2008)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- J' [0/36] Upper state rotational quantum number
4- 6 I3 --- K'a [0/9] Upper state K quantum number
7- 9 I3 --- K'c [0/32] Upper state K quantum number
10- 12 I3 --- J [0/36] Lower state rotational quantum number
13- 15 I3 --- Ka [0/9] Lower state K quantum number
16- 18 I3 --- Kc [0/32] Lower state K quantum number
19- 21 I3 --- F'N [0/36]? Upper state FN=J+IN quantum number
22- 24 I3 --- FN [0/36]? Lower state F quantum number
25- 27 I3 --- 2F'H1 [1/19]? Upper state FH1=FN+IH1
quantum number (x2)
28- 29 A2 --- --- [/2 ]
30- 32 I3 --- 2FH1 [1/19]? Lower state FH1 quantum number (x2)
33- 34 A2 --- --- [/2 ]
35- 46 F12.4 MHz Freq [5288/628741] Observed transition frequencies (1)
47- 54 F8.4 MHz O-C Residuals (2)
55- 60 F6.3 MHz e_Freq Estimated uncertainty of Observed (3)
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Note (1): The frequency of blended transitions or hf components was calculated
as the sum of individual frequencies weighted by the relative intensities.
Note (2): The rms error of residuals of the global fit is 22kHz.
Note (3): The fit standard deviation is 0.971.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- J' [0/36] Upper state rotational quantum number
4- 6 I3 --- K'a [0/9] Upper state K quantum number
7- 9 I3 --- K'c [0/32] Upper state K quantum number
10- 12 I3 --- J [0/36] Lower state rotational quantum number
13- 15 I3 --- Ka [0/9] Lower state K quantum number
16- 18 I3 --- Kc [0/32] Lower state K quantum number
19- 21 I3 --- F'N [0/36] Upper state FN=J+IN quantum number
22- 24 I3 --- FN [0/36] Lower state FN quantum number
25- 36 F12.4 MHz RFreq [399178/973793] Calculated rest frequency
37- 40 F4.1 kHz e_RFreq rms uncertainty on RFreq
41- 48 F8.4 --- LStr Line strength
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Acknowledgements:
Luca Dore, luca.dore(at)unibo.it
(End) Luca Dore [Dept. Chem., Bologna, Italy] Patricia Vannier [CDS] 25-Jun-2012