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Detection of HD in emission towards Sagittarius B2

E. T. Polehampton·J. -P. Baluteau·C. Ceccarelli·B. M. Swinyard·E. Caux
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Abstract

The giant molecular cloud Sagittarius B2, located near the Galactic Centre, has been observed in the far-infrared by the ISO Long Wavelength Spectrometer. Wavelengths in the range 47-196 microns were covered with the high resolution Fabry-Perot spectrometer, giving a spectral resolution of 30-40 km/s. The J=1-0 and J=2-1 rotational transitions of HD fall within this range at 112 microns and 56 microns. A probable detection was made of the ground state J=1-0 line in emission but the J=2-1 line was not detected above the noise. This allowed us to calculate an upper limit on the temperature in the emitting region of approximately 80 K and a value for the deuterium abundance in the Sgr B2 envelope of D/H=(0.2-11)x10^-6.

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E. T. Polehampton, J. -P. Baluteau, C. Ceccarelli, B. M. Swinyard, E. Caux. 2002-04-25. Detection of HD in emission towards Sagittarius B2. https://doi.org/10.1051/0004-6361%3A20020630

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