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We report on a search for Interstellar CH2D+. Four transitions occur in easily accessible portions of the spectrum; we report on emission at the frequencies of these transitions toward high column density star-forming regions. While the observations can be interpreted as being consistent with a detection of the molecule, further observations will be needed to secure that identification. The CH2D+ rotational spectrum has not been measured to high accuracy. Lines are weak, as the dipole moment induced by the inclusion of deuterium in the molecule is small. Astronomical detection is favored by observations toward strongly deuterium-fractionated sources. However, enhanced deuteration is expected to be most significant at low temperatures. The sparseness of the available spectrum and the low excitation in regions of high fractionation make secure identification of CH2D+ difficult. Nonetheless, owing to the importance of CH3+ to interstellar chemistry, and the lack of rotational transitions of that molecule owing to its planar symmetric structure, a measure of its abundance would provide key data to astrochemical models.
We have searched three hot molecular cores for submillimeter emission from the nucleic acid building-block pyrimidine. We obtain upper limits to the total pyrimidine (beam-averaged) column densities towards Sgr B2(N), Orion KL and W51 e1/e2 of 1.7E+1
Life on Earth relies on chiral molecules, that is, species not superimposable on their mirror images. This manifests itself in the selection of a single molecular handedness, or homochirality, across the biosphere. We present the astronomical detecti
We performed a search for the HeH+ J=1-0 line ( u_{rest} = 2010.183873 GHz) and simultaneously for the CH ^2Pi_{3/2}(F_2)J=3/2 - ^2Pi_{1/2}(F_2)J=1/2 lines ( u_{rest}approx 2006.8 and 2010.8 GHz) toward one of the highest-redshift quasars known, SDSS
The diatomic free radical methylidyne (CH) is an important tracer of the interstellar medium and the study of it was critical to our earliest understanding of star formation. Although it is detectable across the electromagnetic spectrum, observations
Spectral line surveys reveal rich molecular reservoirs in G331.512-0.103, a compact radio source in the center of an energetic molecular outflow. In this first work, we analyse the physical conditions of the source by means of CH$_3$OH and CH$_3$CN.