Related papers: The Millimeter-Wave Spectrum of Doubly Deuterated …
The first excited torsional state of the chiral molecule propylene oxide, $\mathrm{CH_{3}C_{2}H_{3}O}$, is investigated from millimeter up to sub-millimeter wavelengths (75-950 GHz). The first excited vibrational mode of propylene oxide,…
Small polycyclic aromatic hydrocarbons and somewhat larger cyano derivatives were detected in the cold dark cloud TMC-1 recently. Their formation from smaller hydrocarbons is not well understood, in part because abundances of many species…
We report the first detection in space of the two doubly deuterated isotopologues of methyl acetylene. The species CHD2CCH and CH2DCCD were identified in the dense core L483 through nine and eight, respectively, rotational lines in the…
Methyl mercaptan (also known as methanethiol), CH3SH, has been found in the warm and dense parts of high -- as well as low -- mass star-forming regions. The aim of the present study is to obtain accurate spectroscopic parameters of the…
The rotational spectra of the two stable conformers syn- and gauche-propanal (CH$_3$CH$_2$CHO) were studied in the millimeter and submillimeter wave regions from 75 to 500 GHz with the Cologne (Sub-)Millimeter wave Spectrometer.…
The dramatic increase in sensitivity, spectral coverage and resolution of radio astronomical facilities in recent years has opened new possibilities for observation of chemical differentiation and isotopic fractionation in protostellar…
We have started a measurement campaign of numerous methanol isotopologs in low-lying torsional states in order to provide extensive line lists for radio astronomical observations from an adequate spectroscopic model and to investigate how…
We report the first detection in space of the single deuterated isotopologue of methyldiacetylene, CH2DC4H. A total of 12 rotational transitions, with J = 8-12 and Ka = 0 and 1, were identified for this species in TMC-1 in the 31.0-50.4 GHz…
The abundances of deuterated molecules with respect to their main isotopologue counterparts have been determined to be orders of magnitude higher than expected from the cosmic abundance of deuterium relative to hydrogen. The increasing…
Methyl mercaptan (CH3SH) is a known interstellar molecule with abundances high enough that the detection of some of its minor isotopologues is promising. The present study aims at providing accurate spectroscopic parameters for the…
A new millimeter- to millimeter-wave double-modulation double-resonance (MMW-MMW DM-DR) scheme has been applied to record spectra of two astronomically relevant complex organic molecules (COMs), propanal (C2H5CHO) and ethyl cyanide…
Propylene oxide, a favorite target of experimental and theoretical studies of circular dichroism, was recently discovered in interstellar space, further amplifying the attention to its role in the current debate on protobiological…
Rotational transitions of $iso$-propyl cyanide, (CH$_3$)$_2$CHCN, also known as $iso$-butyronitrile, were recorded using long-path absorption spectroscopy in selected regions between 37 and 600 GHz. Further measurements were carried out…
The tracking of symmetry-breaking events in space is a longlasting goal of astrochemists, aiming at an understanding of homochiral Earth chemistry. One current effort at this frontier aims at the detection of small chiral molecules in the…
In 2013, we have published the first rotational analysis and detection of mono-deuterated dimethyl ether in the solar-type protostar IRAS 16293-2422 with the IRAM 30m telescope. Dimethyl ether is one of the most abundant complex organic…
We present a new global study of the millimeter (mm) wave, submillimeter (sub-mm) wave, and terahertz (THz) spectra of the lowest three torsional states of methyl mercaptan (CH$_3$SH). New measurements have been carried out between 50 and…
We demonstrate a high-accuracy dual-comb spectrometer centered at 3.4 \mu m. The amplitude and phase spectra of the P, Q, and partial R-branch of the methane {\nu}3 band are measured at 25 MHz to 100 MHz point spacing with ~kHz resolution…
(Abridged) Life is distinctly homochiral. The origins of this homochirality are under active debate. Recently, propylene-oxide has been detected in the gas-phase interstellar medium (ISM) (McGuire et al. 2016). The enantiomeric composition…
The methoxy radical, CH$_3$O, has long been studied experimentally and theoretically by spectroscopists because it displays a weak Jahn-Teller effect in its electronic ground state, combined with a strong spin-orbit interaction. In this…
Ethyl cyanide is an abundant molecule in hot molecular clouds. Lines from 13C isotopically substituted ethyl cyanide were identified in Orion. To enable the search and the possible detection of other isotopologues of ethyl cyanide in…