J/ApJ/723/845 The submillimeter spectrum of glycolaldehyde (Carroll+, 2010)
The submillimeter spectrum of glycolaldehyde.
Carroll P.B., Drouin B.J., Widicus Weaver S.L.
<Astrophys. J., 723, 845-849 (2010)>
=2010ApJ...723..845C 2010ApJ...723..845C
ADC_Keywords: Interstellar medium ; Spectra, millimetric/submm ; Atomic physics
Keywords: ISM: molecules - line: identification - methods: data analysis -
methods: laboratory - molecular data - molecular processes -
radio lines: ISM
Abstract:
Glycolaldehyde (HOCH2CHO) is a sugar-related interstellar prebiotic
molecule that has been detected in two star-forming regions, Sgr B2(N)
and G31.41+0.31. Glycolaldehyde is suspected to form from
photodissociation-driven ice chemistry, and therefore can be used to
trace complex organic chemistry in interstellar environments. The
relative abundance of glycolaldehyde to its structural isomers, methyl
formate (HCOOCH3) and acetic acid (CH3COOH), can be used to
constrain astrochemical models. Given its central role in the complex
chemistry of the interstellar medium, glycolaldehyde has been
suggested as a prime molecular target for upcoming high-frequency
molecular line searches using new far-infrared observatories. In
particular, glycolaldehyde is a target for the Herschel Space
Observatory HEXOS Key Program, which is conducting spectral line
surveys of the Sgr B2(N) and Orion KL star-forming regions across the
entire HIFI band. Laboratory investigation of glycolaldehyde in the
HIFI frequency range is required before its lines can be identified in
these spectra. We have therefore acquired the laboratory spectrum of
glycolaldehyde in selected frequency ranges across the submillimeter
range. We present here the laboratory spectral analysis of the ground
vibrational state of glycolaldehyde up to 1.2THz.
Description:
Spectra were taken in three windows between 520 and 608GHz, 800 and
900GHz, and 1.07 and 1.2THz. In all cases, the spectra were acquired
using a 99% pure glycolaldehyde sample from Sigma-Aldrich. The
520-608GHz and 1.07-1.2THz spectra were obtained at the Jet Propulsion
Laboratory (JPL) molecular spectroscopy lab. The 800-900GHz spectra
were obtained at Emory University using a single-pass direct
absorption flow-cell spectrometer.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 55 1412 Assigned transitions for the the ground vibrational
state of glycolaldehyde
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See also:
J/A+A/540/A51 : Submm spectrum of deuterated glycolaldehydes (Bouchez+, 2012)
J/ApJS/158/188 : Detection of glycolaldehyde toward Sgr B2 (Widicus+, 2005)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- J' [1/63] Upper J level
4- 5 I2 --- Ka' [0/32] Upper Ka level
7- 8 I2 --- Kc' [0/60] Upper Kc level
10- 11 I2 --- J" [0/62] Lower J level
13- 14 I2 --- Ka" [0/31] Lower Ka level
16- 17 I2 --- Kc" [0/59] Lower Kc level
19- 30 F12.4 MHz Freq Frequency observed
31 A1 --- --- [0]
33- 40 F8.5 MHz O-C Observed - Calculated frequency
42- 48 F7.5 MHz e_Freq [0.1] Uncertainty in Freq
50- 55 F6.4 --- Int ? Intensity weighting for blended lines
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 18-Jul-2012