| Autor: |
Tessaro, Veronica, Galassi, Mariel E., Gervais, Benoit, Beuve, Michael |
| Přispěvatelé: |
Rayet, Béatrice, Instituto de Física de Rosario [Santa Fe] (IFIR), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Facultad de Ciencias Exactas, Ingenieria y Agrimensura [Rosario] (FCEIA), Universidad Nacional de Rosario [Santa Fe]-Universidad Nacional de Rosario [Santa Fe], Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: |
angličtina |
| Rok vydání: |
2018 |
| Předmět: |
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| Popis: |
International audience; In many areas of science and technology the ionization of the molecules that constitute the air by ion impact is of great relevance. In astrophysics, the ionization and dissociation of the air molecules by swift ions impact from cosmic radiation and the solar wind provokes different effects on atmosphere. In medical physics, the reference and relative dosimetry is performed using ionization chambers constituted by a cavity that contains air and an electrometer that determine the charge generated after the pass of the ionizing radiation. The measured values are converted to dose in liquid water by applying different correction factors and physical parameters such as the stopping power ratios air/water and the W-values (energy required to generate an ionic pair) [1]. The ionization processes are of relevance in the computation of these physical parameters for protontherapy and hadrontherapy (ion-beam cancer therapy). In a previous article, multiple ionization cross sections (MICS) of carbon monoxide, nitrogen and oxygen by proton impact were calculated using the Independent Electron Model (IEM), describing the molecules as two atoms at the equilibrium distance [2].In the present work, MICS of air molecules by proton and heavy ion impact are calculated applying the IEM taking into account the molecular character of the target. The molecular orbitals are described using the CNDO (Complete Neglect of Differential Overlap) model [3]. An exponential model is used to represent the single particle ionization probabilities as a function of the impact parameter. The single ionization cross sections required are calculated by applying different theoretical models [3,4]. Auger-type emission is analysed, showing the importance of post-collisional contributions to the MICS at high impact energies. The results are in good agreement with experimental data. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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