J/ApJS/117/427 Sgr B2 spectral survey (Nummelin+, 1998)
A three-position spectral line survey of Sagittarius B2 between 218 and 263 GHz.
I. The observational data.
Nummelin A., Bergman P., Hjalmarson A., Friberg P., Irvine W.M.,
Millar T.J., Ohishi M., Saito S.
<Astrophys. J. Suppl. Ser. 117, 427 (1998)>
=1998ApJS..117..427N 1998ApJS..117..427N (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Spectroscopy ; Radio lines
Keywords: ISM: individual name: Sagittarius B2 - ISM: molecules -
line: identification - surveys
Abstract:
We have surveyed the frequency band 218.30-263.55GHz toward the core
positions N and M and the quiescent cloud position NW in the Sgr B2
molecular cloud using the Swedish-ESO Submillimetre Telescope. In
total 1730, 660, and 110 lines were detected in N, M, and NW,
respectively, and 42 different molecular species were identified. The
number of unidentified lines are 337, 51, and eight. Toward the N
source, spectral line emission constitutes 22% of the total detected
flux in the observed band, and complex organic molecules are the main
contributors. Toward M, 14% of the broadband flux is caused by lines,
and SO2 is here the dominant source of emission. NW is relatively poor
in spectral lines and continuum. In this paper we present the spectra
together with tables of suggested line identifications.
Objects:
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RA (2000) DE Designation(s)
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17 47 20.4 -28 23 07 Sgr B2
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 95 1726 Line identifications toward Sagittarius B2(N)
table4.dat 95 664 Line identifications toward Sagittarius B2(M)
table5.dat 92 112 Line identifications toward Sagittarius B2(NW)
tab6-45.dat 165 1861 Lines listed species by species
table46.dat 70 370 Unidentified lines
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Byte-by-byte Description of file: table[345].dat
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Bytes Format Units Label Explanations
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2- 7 I6 MHz Freq Observed frequency
9- 13 F5.2 K Tmb ? Peak main-beam brightness temperature
21- 22 I2 km/s DeltaV ? Velocity width
24- 30 A7 --- Ref Orion references (1)
33- 68 A36 --- Iden Identification
70- 95 A26 --- Rem Remarks
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Note (1): B86: Blake et al., 1986ApJS...60..357B 1986ApJS...60..357B
S85: Sutton et al., 1985ApJS...58..341S 1985ApJS...58..341S
G91: Greaves & White, 1991A&AS...91..237G 1991A&AS...91..237G
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Byte-by-byte Description of file: tab6-45.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- El Element (1)
18- 25 F8.1 MHz RFreq Rest frequency
27- 41 A15 --- State State (2)
43- 69 A27 --- Trans Transition (3)
70- 75 A6 --- n_Trans Note on transition (4)
76- 79 I4 K Eu Upper state energy (5)
81- 87 E7.2 s-1 Aul A-coefficient (5)
89- 94 F6.1 K.km/s N ? Observed integrated intensity at Sgr B2(N) (6)
95 A1 --- n_N [uda] Note (7)
97-102 F6.1 K.km/s M ? Observed integrated intensity at Sgr B2(M)(6)
103 A1 --- n_M [udba] Note (7)
105-109 F5.1 K.km/s NW ? Observed integrated intensity at Sgr B2(NW)(6)
110 A1 --- n_NW [uda] Note (7)
112-171 A60 --- Rem Remarks (8)
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Note (1): SO2 nu2=1 : SO2 in the ν2 = 1 Vibrational State
NH2CN nu=1 : NH2CN in the v = 1 Vibrational State
HC3N 1nu5 : HC3N in the 1ν5 Vibrational State
HC3N 2nu7 : HC3N in the 2ν7 Vibrational State
HC3N 1nu6 : HC3N in the 1ν6 Vibrational State
HC3N 1nu7 : HC3N in the 1ν7 Vibrational State
CH3OH vt=1 : CH3OH in the vt = 1 Torsional State
CH3OH vt=2 : CH3OH in the vt = 2 Torsional State
13CH3OH vt=1 : 13CH3OH in the vt = 1 Torsional State
CH3CN nu8=1 : CH3CN in the ν8 = 1 Vibrational State
CH3CHO vt=1 : CH3CHO in the vt = 1 Torsional State
CH3CHO vt=2 : CH3CHO in the vt = 2 Torsional State
C2H3CN 1nu11 : C2H3CN in the 1ν11 Vibrational State
C2H3CN 1nu15 : C2H3CN in the 1ν15 Vibrational State
C2H3CN 2nu11 : C2H3CN in the 2ν11 Vibrational State
C2H5OH tran : C2H5OH in the tran Substates
C2H5OH gau : C2H5OH in the gauche Substates
CH3OCH3 For most transitions, the splitting of CH3OCH3
into its four torsional substates AA,EE, EA and AE has not been
resolved, and for brevity we only list JKa,Kc in these cases
Note (2): For HCN and HCO+, species
For CH3OH, CH3SH, CH3NH2, CH3CHO, CH3OCHO: symmetry
Symmetry : A, E; a = asymmetric state, s = symmetric state
Note (3): Type of transitions listed:
J: SO+, HCN, HN13C, HCO, N2O, HCS+, OCS, NCNH+,
1{SIGMA} diatomic species (CO, CS, SiO)
JF: NO, NS
NJ: SO, C2H
Jl: HC3N
JK: CH3CN, CH3C2H
JKa,Kc: HDO, SO2, H2CO, HNCO, HOCO+, H2CS+, CH2NH, c-C3H2,
CH2CO, NH2CN, HCOOH, NH2CHO, c-c2H4O, C2H3CN,
CH3OCHO, C2H5OH, CH3OCH3, C2H5CN
JpK: CH3SH
JpKa: CH3OH, CH3NH2
JpKa,Kc: CH3CHO
NKa,Kc: CH2CN
Note (4): F1 corresponds to J = (N + 3/2) -> (N + 1/2)
F2 to J = (N + 1/2) -> (N - 1/2)
a: a-Type Transitions
b: b-type transitions
c: c-type transitions
a/b: a/b-Type transitions
x: x-Type Transitions, See Plummer, Herbst, & De Lucia,
1987ApJ...318..873P 1987ApJ...318..873P
For C2H5OH gau: + -> +; + -> -; - -> -; - -> +
Note (5): 33SO: The Eu and Aul values listed for are derived using the
34SO and SO values
C2H3CN: In case of K-doublets, the Aul values listed refer to the
individual transitions
CH3OCH3: The rest frequencies and Aul values listed always refer to the
subcomponent with highest statistical weight, EE, unless
otherwise stated.
Note (6): Absorption lines have been indicated in the tables by negative
integrated intensities
Note (7): u: up
d: down
a: line intensity incorrect due to emission in reference beam
b: hyperfine-splitting partially resolved
Note (8): a: ambiguous
b: blend
o: overlap
gnd: ground vibrational state of C2H3CN
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Byte-by-byte Description of file: table46.dat
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Bytes Format Units Label Explanations
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1- 6 I6 MHz Freq Observed frequency (1)
8- 11 F4.1 K.km/s N ? Observed integrated intensity at Sgr B2(N)
13- 16 F4.1 K.km/s M ? Observed integrated intensity at Sgr B2(M)
18- 21 F4.1 K.km/s NW ? Observed integrated intensity at Sgr B2(NW) (2)
23- 80 A58 --- Rem Remarks (3)
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Note (1): Assuming VLSR=+62km/s for all three positions.
In case the U-line is common to N and M, the observed frequency
listed is valid for N, and the frequency for M is noted in the
Remarks column, if different. For the U-line that is common to M and
NW (U247563) the listed observed frequency is for M.
Note (2): Absorption lines have been indicated in the tables by negative
integrated intensities
Note (3): S85: Detected by Sutton et al., 1985ApJS...58..341S 1985ApJS...58..341S
B86: Detected by Blake et al., 1986ApJS...60..357B 1986ApJS...60..357B
G91: Detected by Greaves & White, 1991A&AS...91..237G 1991A&AS...91..237G
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History: From electronic version
(End) James Marcout, Patricia Bauer [CDS] 09-Mar-1999