ETD

Archivio digitale delle tesi discusse presso l'Università di Pisa

Tesi etd-12132016-142609


Tipo di tesi
Tesi di dottorato di ricerca
Autore
GUERRI, IRENE
URN
etd-12132016-142609
Titolo
Ion imaging at extremely low and extremely high energy
Settore scientifico disciplinare
FIS/01
Corso di studi
FISICA
Relatori
tutor Prof. Cervelli, Franco
correlatore Prof. Fuso, Francesco
Parole chiave
  • imaging
  • cold atoms
  • AMS-02
Data inizio appello
17/01/2017
Consultabilità
Completa
Riassunto
In this thesis two approaches dealing with charged particle-based imaging at two different energy scales and for radically different purposes have been studied and analyzed. As a consequence, the two experiments involve different beam-matter interaction mechanisms and image reconstruction strategies.
Ion beam imaging (and modifications) of solid state surfaces at the nanometer scale is the first topic considered in this work, where ions are accelerated at a kinetic energy from tens of keV to few keV depending on applications. The activity has been carried out within the EC-FP7 Research Project "Coldbeams", at the laboratories of Dipartimento di Fisica in Pisa and with a secondment period at the enterprise Orsay Physics (Fuveau, France). At Pisa the possibility to create few ions "on demand" from a slow and cold atomic beam has been verified and their dynamic features have been observed and measured. At Orsay Physics an operating prototype of a FIB for surface imaging has been developed using a laser cooled atomic beam as the primary source of ions and its performances has been studied. Even if further work is necessary, the proposed technology is ready for further developments, its engineering and industrialization, so most of the objectives of the "Coldbeams" project has been achieved.
The second topic considered in this work involves the development of an imaging procedure, at a different scale, for a direct check (obtained from flight data!) of the amount of material in every point of the AMS-02 detector and so as a way to verify the presence of any inhomogeneity in its structure. The spectrometer AMS-02 is installed on the IS S since May 2011, and the material distribution is pivotal to build a precise Montecarlo simulation of the experiment. The mechanism is based on the interaction of much more energetic (on the order of tens of GeV) cosmic rays with the detector body. With this imaging procedure the structure of the apparatus has been recognized and elements not included in the official Montecarlo simulation (but responsible of a not negligible amount of interactions) have been identified. Since the application of AMS-02 flight data is only an example of the use of this reconstruction algorithm, an evaluation of the feasibility of the algorithm application during a standard proton test beam has been made.
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