Towards state selective recombination of H3+ under astrophysically relevant conditions

Journal article

We present studies on the thermalisation of H3+ ions in a cold He/Ar/H2 plasma at temperatures 30–70 K. We show that we are able to generate a rotationally thermalised H3+ ensemble with a population of rotational and nuclear spin states corresponding to a particular ion translational temperature. By varying the para-H2 fraction used in the experiment we are able to produce para-H3+ ions with fractional populations higher than those corresponding to thermodynamic values. At 35 K, only the lowest rotational states of para and ortho H3+ are populated. This is the first step towards experimental studies of electron–molecular ion recombination processes with precisely specified quantum states at astrophysically relevant temperatures.

Authors: Dohnal, P; Shapko, D; Kálosi, Á; Kassayová, M; Roučka, Š

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society of Chemistry
• Journal: Faraday Discussions
• Volume: 217
• Pages: 220-234
• Publication date: 2019-01-17
• Acceptance date: 2019-01-17
• DOI: 10.1039/c8fd00214b
• EISSN: 1364-5498
• ISSN: 1359-6640
• Pmid: 31016318
• Language: English
• Keywords: FFR