Production of H+3 via photodissociation of organic molecules in interstellar clouds

Abstract

We present experimental results obtained from photoionization and photodissociation processes of abundant interstellar CH3-X type organic molecules like methanol (CH3OH), methylamine (CH3NH2) and acetonitrile (CH3CN) as alternative route for the production of H + in interstellar and star forming environments. The measurements were taken at the Brazilian Synchrotron Light Laboratory (LNLS), employing soft X-ray photons with energies between 200 and 310 eV and time of flight mass spectrometry. Mass spect ra were obtained using the photoelectron-photoion coincidence techniques. Absolute averaged cross sections for H + production by soft X-rays were determined. We have found that, among the channels leading to molecular dissociation, the H + yield could reach values up to 0.7% for single photoionization process and up to 4% for process involving double photoionization. The H + photoproduction cross section due to the dissociation of the studied organic molecules by photons over the C1s edge (200-310 eV) were about 0.2-1.4 × 10 18 cm 2 . Adopting the typical X-ray luminosity