J/A+AS/142/181 2mm molecular line survey of IRC+10 216 (Cernicharo+, 2000)
A λ 2mm molecular line survey of the C-star envelope IRC+10 216
Cernicharo J., Guelin M., Kahane C.
<Astron. Astrophys. Suppl. Ser. 142, 181 (2000)>
=2000A&AS..142..181C 2000A&AS..142..181C
ADC_Keywords: Stars, carbon ; Radio lines
Keywords: line identification - surveys - stars: AGB and post-AGB -
stars : carbon - stars : circumstellar matter -
stars : individual : IRC+10 216 - radio lines : stars
Abstract:
The mm-wave spectrum of the C-star envelope IRC+10 216 has been
continuously surveyed between 129.0 and 172.5GHz with the IRAM 30-m
telescope. 380 lines are detected, of which 317 have been identified.
The identified lines arise from 30 different molecules and radicals
which, in their vast majority, are not observed in hot and dense
interstellar clouds such as Orion A or W3(OH). Actually, half of the
molecular species identified in the mm-wave spectrum of IRC+10216 were
first observed in the course of this spectral survey.
Objects:
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RA (2000) DE Designation(s)
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09 47 57.3 +13 16 44 IRC+10216
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 112 72 Molecules in this 2mm line survey of IRC+10216
table2.dat 113 399 Observed line parameters in IRC+10216 between
129 and 172.5 GHz
table3.dat 78 63 Unidentified lines
table4.dat 102 27 Observed line parameters for SiS, SiO, SiC
and SiN
table5.dat 101 53 Observed line parameters for SiCC
table6.dat 101 54 Observed line parameters for metal-bearing
species
table7.dat 103 119 Observed line parameters for C3H, C3H2, C4H,
H2C4, C5H and C6H
table8.dat 102 53 Observed line parameters for HCCN, CH3CN, HC3N,
C3N and HC5N
table9.dat 103 26 Observed line parameters for CP, CS, C2S and C3S
tables.tex 117 1322 LaTeX version of the tables
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Mol Molecules observed in the survey (1)
11- 26 A16 --- Iso Isotopic species (the mass numbers are given
only for the rare isotopes)
or excited vibrational states
28- 29 I2 --- Nline Number of lines detected
31 I1 --- Table [4-9] Number of the table containing the line
parameters
33-112 A80 --- Ref Reference to previous publications of partial
data from the survey (includes BibCodes)
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Note (1): Other Species in IRC+10216 not in this 2mm survey :
NH3 SiH4
CN CO HCN HNC HCO+ CH4 MgCN
C2 C2H HCCH H2CCH2
C3 H2C3
C4Si
C5 C5N
H2C6
C7H HC7N
C8H
HC9N
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Mol Molecules (1)
15- 63 A49 --- Trans Rotational transition and vibrational state
(if excited)
64 A1 --- n_Freq [a*] Note on Freq (2)
65- 72 F8.1 MHz Freq ? Observed line frequency
74- 75 I2 MHz e_Freq ? 1 sigma error bar in Freq
76- 77 A2 --- nFreq [+ ] ++: Frequency has been fixed to the
calculated value
79- 88 F10.3 MHz Freqc ? Calculated line frequency in MHz
89 A1 --- u_Freqc [)] Uncertainty flag on Freqc
91- 96 F6.2 K.km/s T(MB)dv ? Line integrated intensity in main beam
temperature scale
98- 99 I2 K.km/s e_T(MB)dv ? rms uncertainty on T(MB)dv
102-105 F4.1 km/s Vexp ? Expansion velocity derived from the line
width (3)
107-108 I2 km/s e_Vexp ? rms uncertainty on Vexp
110-114 A5 --- Notes []+$#%*& [] Notes precising the conditions
of the line fit and the derivation of the
line parameters (G1)
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Note (1): Unidentified lines are referenced by Unnnnnn where nnnnnn is the
line frequency in MHz
Note (2): the symbols have the following meaning:
*: Frequency corresponds to the that of the strongest hyperfine
component
a: Calculated frequency corresponds to the average of the different
hyperfine components
Note (3): The value 14.5 given without 1 sigma error bar means that the model
fit to the line used to derive the line integrated intensity uses
this fixed value.
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Name Unidentified lines (1)
9- 34 A26 --- Trans Tentative identification
36- 43 F8.1 MHz Freq Observed line frequency
45- 46 I2 MHz e_Freq 1 sigma error bar on Freq
48 A1 --- --- [(]
49- 58 F10.3 MHz Freqc ? Calculated line frequency
59 A1 --- u_Freqc [)] Uncertainty flag on Freqc
61- 64 F4.2 K.km/s T(MB)dv Line integrated intensity in main beam
temperature scale
66- 67 I2 K.km/s e_T(MB)dv rms uncertainty on TMBdv
69- 72 F4.1 km/s Vexp Expansion velocity derived from the line
width (2)
74- 75 I2 km/s e_Vexp ? rms uncertainty on Vexp
77- 79 A3 --- Notes Notes precising the conditions of the line fit
and the derivation of the line parameters (G1)
--------------------------------------------------------------------------------
Note (1): Unidentified lines, referenced by Unnnnnn where nnnnnn is the line
frequency in MHz
Note (2): The value 14.5 given without 1 sigma error bar means that the model
fit to the line used to derive the line integrated intensity uses
this fixed value.
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Byte-by-byte Description of file: table[4-9].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Mol Molecules
13- 55 A43 --- Trans Rotational transition and vibrational state
(if excited) (1)
57- 64 F8.1 MHz Freq ? Observed line frequency
66- 67 I2 MHz e_Freq ? 1 sigma error bar on νobs
68- 69 A2 --- n_Freq [++ ] ++: Frequency has been fixed to the
calculated value
71- 80 F10.3 MHz Freqc ? Calculated line frequency
82- 87 F6.2 K.km/s T(MB)dv ? Line integrated intensity in main beam
temperature scale
89- 90 I2 K.km/s e_T(MB)dv ? rms uncertainty on T(MB)dv
92- 95 F4.1 km/s Vexp ? Expansion velocity derived from the
line width (2)
97- 98 I2 km/s e_Vexp ? rms uncertainty on Vexp
100-103 A4 --- Notes Notes precising the conditions of the line
fit and the derivation of the line
parameters (G1)
--------------------------------------------------------------------------------
Note (1): bracketed symbols mean the following:
<+>: frequency corresponds to the that of the strongest hyperfine
component
<>: calculated frequency corresponds to the average of the different
hyperfine components
Note (2): The value 14.5 given without 1 sigma error bar means that the model
fit to the line used to derive the line integrated intensity uses
this fixed value.
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Table 10 : Molecular column densities
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Molecule. Trot Col. Dens. t Frac. abund.
Kelvin cm-2 N(X)/N(H2.)
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C2H 20 5.0E+15^ 7.1E-6
l-C3H 20 7.0E+13^ 1.0E-8
C4H 35 3.0E+15^ 4.3E-6
C5H 25 4.4E+13^ 6.3E-8
C6H 35 5.5E+13^ 7.8E-8
C7H 35 2.2E+12^ 3.1E-9
C8H 52 1.0E+13^ 1.4E-8
C3N 20 2.5E+14^ 3.5E-7
C5N 35a 6.3E+12^ 9.0E-9
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Notes: a: assumed;.
t: total column density across the source,
i.e. twice the radial column density.
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Table 11: Elemental isotopic abundance ratios
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Isotopic ratio average value solar value Comments
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29Si/30Si 1.45 (0.13) 1.52
28Si/29Si 15.4 (1.1 ) 19.6 opacity
28Si/30Si 20.3 (2.0 ) 29.8 opacity
33S/34S 0.18 (0.1 ) 0.18
32S/34S 21.8 (2.6 ) 22.5
32S/33S 62 (8. ) 125. opacity
12C/13C 45 (3. ) 89.
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Global Notes:
Note (G1): the following symbols are used to describe the conditions
of the line fit and the derivation of the line parameters:
+: Assumed width at half power of 14.5 km/s
*: blend of hyperfine lines or K-doublets of the same molecule
$: blended with another line. Line separation allows an individual
fit for each line
#: blend of two of more lines. Only a line is fitted
&: Average of two of more hyperfine lines
[]: Line too narrow for the expected width of normal lines in IRC+10216
Acknowledgements: Claudine Kahane
(End) Patricia Bauer [CDS] 13-Jan-2000