naa a22 4500 510774466 CHVBK 20180411083225.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s12210-012-0215-z doi (NATIONALLICENCE)springer-10.1007/s12210-012-0215-z Production of ions at high energy and its role in extraterrestrial environments [Elektronische Daten] [Michele Alagia, Nadia Balucani, Pietro Candori, Stefano Falcinelli, Fernando Pirani, Robert Richter, Marzio Rosi, Stefano Stranges, Franco Vecchiocattivi] Ions in space are formed in various ways, the relevance of which depends on the specific conditions of the considered extraterrestrial environment. The interaction of neutral molecules with cosmic rays, UV photons, X-rays and other phenomena such as shock waves are all important processes for their production. Once formed, ions are able to drive some chemistry that leads to molecular ions and, via dissociative recombination, molecules of increasing complexity. Therefore, ion-chemistry plays a pivotal role in the chemistry of the interstellar medium and upper planetary atmospheres (ionospheres). Molecular ions have also been detected in comet tails. In this paper, we briefly review experimental results obtained in our laboratory and concerning the formation of free ions in two different types of processes: double photoionization and collisional ionization induced by highly excited species (Penning ionization). A detailed characterization of these processes in laboratory experiments is of crucial importance to understand the chemistry of extraterrestrial environments. The double photoionization occurs when high energy photons are available and, as dications are generally metastable and rapidly decay into two fragment ions, contributes to the global budget of ion formation. The effects of Penning ionization have never been considered in modeling extraterrestrial objects so far, even though metastable helium is known to be formed by radiative recombination of He+ ions with electrons. Because helium is the second most abundant element of the Universe, Penning ionization of molecules by He*(23S1) is plausibly an active route of ionization in relatively dense environments exposed to cosmic rays. Accademia Nazionale dei Lincei, 2012 Molecular ionization nationallicence Penning ionization nationallicence Synchrotron radiation ionization nationallicence Molecular double ionization nationallicence Astrochemistry nationallicence Alagia Michele IOM CNR Laboratorio TASC, 34012, Trieste, Italy aut Balucani Nadia Dipartimento di Chimica, Università di Perugia, 06123, Perugia, Italy aut Candori Pietro Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut Falcinelli Stefano Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut Pirani Fernando Dipartimento di Chimica, Università di Perugia, 06123, Perugia, Italy aut Richter Robert Sincrotrone Trieste, Area Science Park, 34149, Trieste, Basovizza, Italy aut Rosi Marzio Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut Stranges Stefano IOM CNR Laboratorio TASC, 34012, Trieste, Italy aut Vecchiocattivi Franco Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut Rendiconti Lincei Springer Milan 24/1(2013-03-01), 53-65 2037-4631 24:1<53 2013 24 12210 https://doi.org/10.1007/s12210-012-0215-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12210-012-0215-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Alagia Michele IOM CNR Laboratorio TASC, 34012, Trieste, Italy aut NATIONALLICENCE 700 1- Balucani Nadia Dipartimento di Chimica, Università di Perugia, 06123, Perugia, Italy aut NATIONALLICENCE 700 1- Candori Pietro Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut NATIONALLICENCE 700 1- Falcinelli Stefano Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut NATIONALLICENCE 700 1- Pirani Fernando Dipartimento di Chimica, Università di Perugia, 06123, Perugia, Italy aut NATIONALLICENCE 700 1- Richter Robert Sincrotrone Trieste, Area Science Park, 34149, Trieste, Basovizza, Italy aut NATIONALLICENCE 700 1- Rosi Marzio Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut NATIONALLICENCE 700 1- Stranges Stefano IOM CNR Laboratorio TASC, 34012, Trieste, Italy aut NATIONALLICENCE 700 1- Vecchiocattivi Franco Dipartimento di Ingegneria Civile ed Ambientale, Università di Perugia, 06125, Perugia, Italy aut NATIONALLICENCE 773 0- Rendiconti Lincei Springer Milan 24/1(2013-03-01), 53-65 2037-4631 24:1<53 2013 24 12210 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer