J/A+A/687/A8 3-Hydroxypropenal transitions (Mueller+, 2024)
The rotation-tunneling spectrum of 3-hydroxypropenal and confirmation of its
detection toward IRAS 16293-2422 B.
Mueller H.S.P., Coutens A., Jorgensen J.K., Margules L., Motiyenko R.A.,
Guillemin J.-C.
<Astron. Astrophys. 687, A8 (2024)>
=2024A&A...687A...8M 2024A&A...687A...8M (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: molecular data - methods: laboratory: molecular -
techniques: spectroscopic - radio lines: ISM - ISM: molecules -
astrochemistry
Abstract:
3-Hydroxypropenal (HOCHCHCHO) is the lower energy tautomer of
malonaldehyde which displays a complex rotationtunneling spectrum. It
was detected some- what tentatively toward the solar-type protostellar
system IRAS 16293-2422 with ALMA in the framework of the Protostellar
Interferometric Line Survey (PILS). Several transitions, however, had
large residuals, preventing not only their detection, but also the
excitation temperature of the species from being determined
unambiguously.
We want to extend the existing rotational line list of
3-hydroxypropenal to shed more light on the recent observational
results and to facilitate additional radio astronomical searches for
this molecule.
We recorded and analyzed the rotation-tunneling spectrum of
3-hydroxypropenal in the frequency regions between 150 and 330 GHz and
between 400 and 660 GHz. Transitions were searched for in the PILS
observations of IRAS 16293-2422. Local thermodynamic equilibrium (LTE)
models were carried out and compared to the observations to constrain
the excitation temperature. Additional transitions were searched for
in other ALMA archival data of the same source to confirm the presence
of 3-hydroxypropenal.
More than 7500 different spectral lines, corresponding to more than
11500 transitions, were assigned in the course of our investigation
with quantum numbers 2≤J≤100, Ka≤59, and Kc≤97, resulting in a
greatly improved set of spectroscopic parameters. The comparison
between the LTE models and the observations yields an excitation
temperature of 125K with a column density N=1.0x1015cm-2 for this
species. We identified seven additional lines of 3-hydroxypropenal
that show a good agreement with the model in the ALMA archive data.
The calculated rotation-tunneling spectrum of 3-hydroxypropenal has
sufficient accuracy for radio astronomical searches. With the solution
of the excitation temperature conundrum and the detection of seven
more lines, we consider the detection of 3-hydroxypropenal toward IRAS
16293-2422 as secure.
Description:
We recorded and analyzed the rotation-tunneling spectrum of
3-hydroxy-propenal in the frequency regions between 150 and 330GHz
and between 400 and 660GHz. Transitions were searched for in the PILS
observations of IRAS 16293-2422. Local thermodynamic equilibrium (LTE)
models were carried out and compared to the observations to constrain
the excitation temperature. Additional transitions were searched for
in other ALMA archival data of the same source to confirm the presence
of 3-hydroxypropenal.
More than 7500 different spectral lines, corresponding to more than
11500 transitions, were assigned in the course of our investigation
with quantum numbers 2≤J≤100, Ka≤59, and Kc≤97, resulting
in a greatly improved set of spectroscopic parameters. The comparison
between the LTE models and the observations yields an excitation
temperature of 125K with a column density N=1.0x1015cm-2 for
this species. We identified seven additional lines of
3-hydroxypropenal that show a good agreement with the model in the
ALMA archive data.
The calculated rotation-tunneling spectrum of 3-hydroxypropenal has
sufficient accuracy for radio astronomical searches. With the solution
of the excitation temperature conundrum and the detection of seven
more lines, we consider the detection of 3-hydroxypropenal toward
IRAS 16293-2422 as secure.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
3-hp.dat 102 11641 Transitions included in the fit of
3-Hydroxypropenal
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Byte-by-byte Description of file: 3-hp.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 4 I3 --- J' Upper state J quantum number
6- 7 I2 --- Ka' Upper state Ka quantum number
9- 10 I2 --- Kc' Upper state Kc quantum number
13 I1 --- v' Upper state v; 0 = 0+; 1 = 0-
17- 19 I3 --- J" Lower state J quantum number
21- 22 I2 --- Ka" Lower state Ka quantum number
24- 25 I2 --- Kc" Lower state Kc quantum number
28 I1 --- v" Lower state v; 0 = 0+; 1 = 0-
33- 43 F11.4 MHz FreqObs Observed transition frequency
48- 53 F6.4 MHz e_FreqObs Experimental uncertainty
57- 64 F8.5 MHz (O-C) Observed minus calculated frequency
(for group of lines if they are at the same
frequency)
68- 73 F6.4 --- wb ? Weight of the component in group of lines
76-102 A27 --- Notes Source of data (reference) (1)
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Note (1): References as follows:
S. L. Baughcum et al., 1981 = Baughcum et al., 1981,
J. Am. Chem. Soc., 103, 6296
Stolze et al., 1983 = Stolze et al., 1983, J. Mol. Struct., 97, 243
This work = This work
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Acknowledgements:
Holger Mueller, hspm(at)ph1.uni-koeln.de
References:
Coutens et al., 2022A&A...660L...6C 2022A&A...660L...6C,
First tentative detection of 3-hydroxypropenal
Zakharenko et al, 2015JMoSp.317...41Z 2015JMoSp.317...41Z,
Terahertz spectroscopy using a frequency multiplication chain
Mueller et al., 2001A&A...370L..49M 2001A&A...370L..49M,
Cologne Database for Molecular Spectroscopy
Endres et al., 2016JMoSp.327...95E 2016JMoSp.327...95E,
The CDMS in the Virt. At. & Mol. Data Centre
(End) Patricia Vannier [CDS] 04-May-2024