Extended Data Fig. 8: Laser ionization analogue spectrum of pyrene in water–acetic acid mixture. | Nature

Extended Data Fig. 8: Laser ionization analogue spectrum of pyrene in water–acetic acid mixture.

From: Macromolecular organic compounds from the depths of Enceladus

Extended Data Fig. 8

Cationic TOF mass spectrum recorded with the liquid microbeam ionization setup (see Methods, ‘Laser dispersion analogue experiments for icy dust impacts’, and Extended Data Fig. 9) containing 0.1% pyrene dissolved in a mixture of water and acetic acid. The laser pulse simulates an ice grain impact with a speed78 of about 10 km s−1. Features marked as ‘pyrene fragment’ do not appear in the blank experiment with just the solvent mixture and are either direct pyrene fragments or cations formed from pyrene fragments clustering with the solvent (for example, at 159 u). The molecular mass lines of pyrene are about 10 times more abundant than those of any fragments, indicating the stability of the PAH molecule. In contrast to CDA HMOC spectra, no isolated benzene ring fragment (77 u or 91 u) forms.