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J/A+A/406/L47    17OH spin-rotation transition frequencies  (Polehampton+, 2003)

Far-infrared detection of 17OH towards Sagittarius B2. Polehampton E.T., Brown J.M., Swinyard B.M., Baluteau J.-P. <Astron. Astrophys. 406, L47 (2003)> =2003A&A...406L..47P
ADC_Keywords: Atomic physics ; Interstellar medium ; Infrared sources Keywords: infrared: ISM - molecular data - ISM: molecules - line: identification - ISM: individual objects: Sagittarius B2 Abstract: The frequencies and line strengths of the 2Π3/2 J=5/2-3/2 rotational transition of 17OH have been calculated from an analysis of its far-infrared laser magnetic resonance spectrum. These results have been used to make the first detection of a pure rotational transition of 17OH in the ISM. Two resolved components of this transition appear in absorption towards the giant molecular cloud Sagittarius B2, which was observed at a spectral resolution of 33km/s with the Fabry-Perot mode of the ISO Long Wavelength Spectrometer. The corresponding transition of 18OH was also observed and its line shape was modelled using HI measurements. The 18O/17O ratio of 3.5 was then used to compare this with the observed 17OH line shape. Description: Frequencies and line strengths for spin-rotation transitions of 17OH are presented for energy levels up to and including 2Π3/2 J=7/2. These were predicted by a computer program that used the molecular parameters obtained from laser magnetic resonance measurements by Leopold et al. (1987, J. Mol. Spec, 122, 440L. This program is described in detail by Brown et al. (1978, Mol. Phys., 36, 553). The calculation was performed taking account of the 17O nuclear spin but ignoring the 1H nuclear spin, which causes a further splitting of each level in to a doublet. The uncertainty in frequency prediction is approximately 2MHz. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file freq17oh.dat 54 232 Frequencies, wavelengths and line strengths
See also: J/ApJS/117/427 : Sgr B2 spectral survey (Nummelin+, 1998) Byte-by-byte Description of file: freq17oh.dat
Bytes Format Units Label Explanations
1 I1 --- Fsu [1,2] Spin state upper (1) 3 I1 --- Fsl [1,2] Spin state lower (1) 6- 8 F3.1 --- Ji Rotation quantum number upper 10- 12 F3.1 --- Jj Rotation quantum number lower 15 I1 --- Fi Total angular momentum quantum number upper 16 A1 --- Pi [-+] Parity upper state (2) 18 I1 --- Fj Total angular momentum quantum number lower 19 A1 --- Pj [-+] Parity lower state (2) 22- 28 I7 MHz Freq ? Frequency (3) 33- 42 F10.6 um Wav ? Wavelength (3) 45- 53 F9.7 --- Sij ? Line Strength (3)
Note (1): 1 denotes the 2Π3/2 state and 2 denotes the 2Π1/2 state. Note (2): '+' denotes even parity and '-' denotes odd parity. Note (3): In six cases the frequency, wavelength and line strength could not be determined. In these cases, the three last columns are blank.
Acknowledgements: Edward Polehampton
(End) Edward Polehampton [MPIfR, Germany] 01-Jul-2003
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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