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arXiv · 2305.19641

A high-resolution spectroscopic analysis of aminoacrylonitrile and an interstellar search towards G+0.693

D. Alberton·V. Lattanzi·C. Endres·V. M. Rivilla·J. C. Guillemin·P. Caselli·I. Jiménez-Serra·J. Martín-Pintado
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Abstract

Cyanides, ranging from three carbon atoms to PAHs, and alkenyl compounds are abundant in the interstellar medium (ISM). Aminoacrylonitrile (3-Amino-2-propenenitrile, H$_{2}$N-CH=CH-CN), an alkenyl cyanide, thus represents a promising candidate for new interstellar detection. A comprehensive spectroscopic laboratory investigation of aminoacrylonitrile in its rotational ground vibrational state has been herein performed. The measurements carried out up to the THz regime made it possible to generate a precise set of reliable rest frequencies for its search in space up to sub-millimetre wavelengths. The $Z$-aminoacrylonitrile ($Z$-apn) isomer spectrum has been recorded employing a source-modulated sub-millimetre spectrometer, from 80 GHz to 1 THz. A combination of Doppler and sub-Doppler measurement regimes allowed to record 600 new lines. The collected data have enabled the characterisation of a set of spectroscopic parameters up to decic centrifugal distortion constants. The catalogue generated from the improved spectral data has been used for the search of $Z$-apn in the spectral survey of the G+0.693-0.027 molecular cloud located in the central molecular zone, in the proximity of the Galactic centre.

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D. Alberton, V. Lattanzi, C. Endres, V. M. Rivilla, J. C. Guillemin, P. Caselli, I. Jiménez-Serra, J. Martín-Pintado. 2023-05-31. A high-resolution spectroscopic analysis of aminoacrylonitrile and an interstellar search towards G+0.693. https://doi.org/10.3847/1538-4357%2Facd8bd

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