The Detection of Interstellar Ethanimine (CH3CHNH) from Observations taken during the GBT PRIMOS Survey

TL;DR

This study reports the detection of interstellar ethanimine molecules in space using broadband rotational spectroscopy, linking laboratory measurements with radio telescope data, and discusses its potential role in amino acid formation.

Contribution

First identification of interstellar ethanimine using combined laboratory and radio astronomy spectroscopy, suggesting its role in prebiotic chemistry.

Findings

Detection of E- and Z-ethanimine in Sagittarius B2(N)

Matching laboratory spectra with astronomical observations

Discussion of interstellar formation pathways

Abstract

We have performed reaction product screening measurements using broadband rotational spectroscopy to identify rotational transition matches between laboratory spectra and the Green Bank Telescope PRIMOS radio astronomy survey spectra in Sagittarius B2 North (Sgr B2(N)). The broadband rotational spectrum of molecules created in an electrical discharge of CH3CN and H2S contained several frequency matches to unidentified features in the PRIMOS survey that did not have molecular assignments based on standard radio astronomy spectral catalogs. Several of these transitions are assigned to the E- and Z-isomers of ethanimine. Global fits of the rotational spectra of these isomers in the range of 8 to 130 GHz have been performed for both isomers using previously published mm-wave spectroscopy measurements and the microwave measurements of the current study. Possible interstellar chemistry formation routes for E-ethanimine and Z-ethanimine are discussed. The detection of ethanimine is significant because of its possible role in the formation of alanine - one of the twenty amino acids in the genetic code.