J/ApJS/190/315 Rotational spectrum of H13COOCH3 (Carvajal+, 2010)
Global assignment and extension of millimeter- and submillimeter-wave spectral
database of 13C1-methyl formate (H13COOCH3) in the ground and first
excited states.
Carvajal M., Kleiner I., Demaison J.
<Astrophys. J. Suppl. Ser., 190, 315-321 (2010)>
=2010ApJS..190..315C 2010ApJS..190..315C
ADC_Keywords: Interstellar medium ; Atomic physics ; Spectra, millimetric/submm
Keywords: catalogs - ISM: molecules - methods: data analysis -
submillimeter: ISM - techniques: spectroscopic
Abstract:
A compilation of the available spectroscopic millimeter- and
submillimeter-wave data of the ground and first excited states of
13C1-methyl formate (H13COOCH3) has been carried out. The
exhaustive analysis of the available transition lines of H13COOCH3
has led to the assignment of 7457 spectral lines by means of a global
fit of 45 parameters, using the Rho-Axis Method (RAM) and the BELGI-Cs
code, with a resulting unitless standard deviation of 0.57. Over 1600
lines are included for the first time in the fit. In addition, the
line strengths of spectral lines are also calculated using the most
recent experimental measurement of the electric dipole moment. In
conclusion, the present study represents a notable improvement with
respect to previous H13COOCH3 spectral analyses. Therefore, the
better accuracy of the present analysis may help the future
identification of new H13COOCH3 lines in the interstellar and
circumstellar media, and may contribute to decrease some of the
spectral confusion due to these species in astronomical surveys.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 112 7342 Assignments, observed frequencies, calculated
frequencies, residuals from the RAM fit, line
strengths, and lower energy levels for
13C1-methyl formate (H13COOCH3) microwave
transitions from vt=0 and vt=1 torsional states
included in the fit with parameters of Table 2
table2.dat 88 45 Torsion-Rotation parameters needed for the
global fit of transitions involving vt=0 and
vt=1 torsional energy levels of H13COOCH3
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See also:
J/A+A/500/1109 : Rotational spectrum of HCOO13CH3 (Carvajal+, 2009)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- LNum Line number (1)
8- 28 A21 --- Upper Upper state information (2)
31- 51 A21 --- Lower Lower state information (2)
53- 62 F10.3 MHz OFreq Observed frequency
64- 68 F5.3 MHz e_OFreq Uncertainty in OFreq
70- 79 F10.3 MHz CFreq Calculated frequency
81- 85 F5.3 MHz e_CFreq Uncertainty in CFreq
87- 93 F7.3 D+2 LStr Line strength; see text for details
95-102 F8.4 cm-1 E Lower state energy (3)
104-110 A7 --- Ref Reference(s) (4)
112 A1 --- f_LNum [BC] Flag on line (5)
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Note (1): Line number given to sort the lines by J and K sub-branches if needed.
Note (2): In the format vt, J, Ka, Kc, and P. Upper and lower state
quantum numbers are indicated by ' and " respectively.
Torsion-rotation levels of A species have a "parity" label; levels
of E species have a signed Ka value (Herbst et al.,
1984JMoSp.108...42H 1984JMoSp.108...42H). Note that for degenerate transitions, only the
sum of line strengths of the degenerate transitions for a given
cluster is preserved. Therefore the degenerate clusters of transitions
is represented by only one transition frequency accompanied by the sum
of line strengths calculated for the cluster components. For those
cases, instead of the usual label J, Ka, Kc, the cluster is
represented by the rotational state designation J, * where the
asterisk stands for the two degenerate levels with the same J, Kc
but with different Ka quantum numbers, or with the same J, Ka but
with different Kc quantum numbers. In the parentheses, for the
A-species, the two different Ka (or Kc) levels and the parity
quantum number + or - are indicated and means that those two levels
are degenerate within the selected cutoff (0.005MHz). For the
E-species, the parentheses contains + or -Ka (Kc) and it means
that those two levels are degenerate within the same selected cutoff
(0.005MHz).
Note (3): Refered to the J=Ka=0 A-species energy level taken as the zero
of the energy (zero point torsional energy : 71.3465cm-1).
Note (4): Sources of data as follows:
L-FTMW = Lille Fourier Transform Microwave Spectrometer (Carvajal et al.,
2009A&A...500.1109C 2009A&A...500.1109C); they are reported for the first time;
WILLA = Willaert et al. (2006JMoSt.795....4W 2006JMoSt.795....4W);
FASSST = Maeda et al. (2008ApJS..175..138M 2008ApJS..175..138M);
LABEL = reported by Maeda et al. (2008ApJS..175..138M 2008ApJS..175..138M) but with different
assignment, see the text;
FASSST2 = data were reported and fitted by Maeda et al. (2008JMoSp.251..293M 2008JMoSp.251..293M);
NEW = data are fitted for the first time in the present work but recorded
and tentatively assigned by Maeda et al. (2008JMoSp.251..293M 2008JMoSp.251..293M).
Note (5): Flag as follows:
B = Blended lines. They should be resolved with a spectrometer with a
better resolution.
C = Two corrected lines of Willaert et al. (2006JMoSt.795....4W 2006JMoSt.795....4W)
because of their symmetries being interchanged.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- nlm ? Total order of the operator (n) (1)
5- 46 A42 --- Op Operator (2)
48- 65 A18 --- Param Parameter
67- 88 A22 --- Value Parameter value in cm-1 except for ρ (3)
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Note (1): Notation from Ilyushin et al. (2003JMoSp.220..170I 2003JMoSp.220..170I); n=l+m, where n is
the total order of the operator, l is the order of the torsional part,
and m is the order of the rotational part.
Note (2): Notation from Ilyushin et al. (2003JMoSp.220..170I 2003JMoSp.220..170I). {A,B}=AB+BA. The
product of the parameter and operator from a given row yields the term
actually used in the vibration-rotation-torsion Hamiltonian, except
for F, ρ, and ARAM, which occur in the Hamiltonian in the form
F(Pα-ρPa)2+ARAMP2a.
Note (3): Values of the parameters in cm-1 given in the present work, except
for ρ which is unitless. Statistical uncertainties are given in
parentheses in units of the last quoted digit.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-Oct-2010