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تسجيل مستخدم جديدDetection of Interstellar Acetone Toward the Orion-KL Hot Core
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We present the first detection of interstellar acetone [(CH3)2CO] toward the high mass star forming region Orion-KL and the first detection of vibrationally excited (CH3)2CO in the ISM. Using the BIMA Array, 28 emission features that can be assigned to 54 acetone transitions were detected. Furthermore, 37 of these transitions have not been previously observed in the ISM. The observations also show that the acetone emission is concentrated toward the hot core region of Orion-KL, contrary to the distribution of other large oxygen bearing molecules. From our rotational-temperature diagram we find a beam averaged (CH3)2CO column density of (2.0(0.3)-8.0(1.2))x10^16 cm^-2 and a rotational temperature of 176(48)-194(66) K.
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We present sensitive high angular resolution submillimeter and millimeter observations of torsionally/vibrationally highly excited lines of the CH$_3$OH, HC$_3$N, SO$_2$, and CH$_3$CN molecules and of the continuum emission at 870 and 1300 $mu$m from
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Comparison of their chemical compositions shows, to first order, a good agreement between the cometary and interstellar abundances. However, a complex O-bearing organic molecule, ethylene glycol (CH$_{2}$OH)$_{2}$, seems to depart from this correlati
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