SIMBAD references

This paper describes a near-UV/VIS study of a pyrene:H₂ O interstellar ice analogue at 10 K using optical absorption spectroscopy. A new experimental approach makes it possible to irradiate the sample with vacuum ultraviolet (VUV) light (7-10.5 eV) while simultaneously recording spectra in the 240-1000 nm range with subsecond time resolution. Both spectroscopic and dynamic information on VUV processed ices are obtained in this way. This provides a powerful tool to follow, in situ and in real time, the photophysical and photochemical processes induced by VUV irradiation of a polycyclic aromatic hydrocarbon containing inter- and circumstellar ice analogue.
Result. on the VUV photolysis of a prototype sample–strongly diluted pyrene in H₂ O ice–are presented. In addition to the pyrene cation (Py⁺), other products–hydroxypyrene (PyOH), possibly hydroxypyrene cation (PyOH⁺), and pyrene/pyrenolate anion (Py^–/PyO^–)–are observed. It is found that the charge remains localized in the ice, also after the VUV irradiation is stopped. The astrochemical implications and observational constraints are discussed.