Andrea Casolari
Report on the activities carried out in the PhD period
Training
During the first year of the PhD period at Università di Pisa I attended the following classes: 1. “Physics of compact stars”, class held by Prof. Ignazio Bombaci, Università di Pisa 2. “Complex systems”, class held by Prof. Riccardo Mannella, Università di Pisa 3. “Advanced course of Physics of Matter”, consisting in a series of lectures and
seminars on three main topics of physics of matter:
• “Equilibrium and non-equilibrium Green’s functions with applications to solid state physics and nano-scale devices”, series of lectures held by Prof. Giuseppe Pastori Parravicini, Università di Pavia
• “Introduction to modeling and simulations”, series of lectures held by Dr. Francesco Puosi, University Joseph Fourier, Grenoble
• Plasma physics seminars:
- “Space plasmas: from spacecraft observations to plasma theory”, Dr. Pierre Henri, CNRS, Orléans
- “Pulsed high power lasers” and “The 20PW OPCPA laser system”, Dr. Marco Galimberti, Rutherford Appleton Laboratory, Oxfordshire
- “Novel aspects of classical and quantum radiation reaction”, Dr. Antonino Di Piazza, Max-Planck-Institut für Kernphysik, Heidelberg - “Laser-driven inertial confinement fusion: principle, issue, achievement”, Prof. Stefano Atzeni, Università degli Studi di Roma La Sapienza
- “Introduction to electric propulsion”, Dr. Tommaso Andreussi, SITAEL SPA
- “Studies of plasma physics in magnetic confinement devices”, Dr. Paolo Buratti, ENEA, Frascati
I attended the XXIX Summer School on Mathematical Physics, which was held in Ravello in the summer 2014. The subjects covered by the courses where advanced topics in mathematics, mathematical physics and plasma physics.
I attended the 12th Carolus Magnus Summer School, which was held in Leuven in the summer 2015. The courses covered a large number of opics on plasma physics for magnetic confinement.
Research activity
I spent two years of my PhD period in ENEA research center in Frascati to work with Dr. Paolo Buratti on magnetic islands related issues. Initially I contributed to the interpretation of the experimental observations about magnetic island rotation is Joint Europen Torus
(JET). In particular, I examined the different theoretical models currently used to check their accuracy in describing the experimental results. At the same time I contributed to write a paper on some diagnostic applications of the measurement of the island rotation velocity. Then I tried to develop a theoretical model to describe the plasma dynamics close to a magnetic island and the island rotation velocity in a consistent way. To this purpose I studied the most widely used models and I tried to find their weaknesses. In particular I tried to deduce a system of four-field equations including the finite-Larmor-radius (FLR) effects, originating from the small-length dynamics, and the neoclassical effects, arising from the toroidal shape of the tokamak, as much self-consistently as possible. Eventually, I contributed to the study of the phenomenon named "limit cycles", consisting in a particular regime of magnetic island propagation, which has been recently observed in Frascati Tokamak Upgrade (FTU). To this purpose, I performed numerical integrations of a system of four-field equations by using a code which was lent to me by Dr. Daniela Grasso from CNR and Politecnico di Torino. The analytic study regarding the theoretical model I developed and the numerical study on the "limit cycles" represent the main content of my PhD thesis.
Seminars
I gave a short seminar on the subject of magnetic island dynamics in 2014 in Università di Pisa, as part of the mandatory tasks of PhD students.
I gave a second seminar on the same subject in 2015 in Università di Pisa, showing the progression in my work, as part of the evaluation of the students work.
I gave a brief seminar on the subject of my master degree thesis (study of Lower Hybrid Waves propagation in tokamaks) during the XXIX Summer School on Mathematical Physics, Ravello, 2014.
I presented a summary of my research on the subject of plasma physics for magnetic confinement, covering both my master thesis work and my PhD work, at the Institute of Plasma Physics (IPP) in Prague in 2016, while applying for a postdoc position.
Summer schools and conferences
- I attended the XXIX Summer School on Mathematical Physics, which was held in Ravello in the summer 2014. On that occasion I gave a brief seminar on the subject of my master degree thesis, which was about the study of Lower Hybrid Waves propagation in tokamaks. - I attended the 12th Carolus Magnus Summer School, which was held in Leuven in the summer 2015. On that occasion I presented a poster on the analytical studies I made on the magnetic island propagation.
- I attended the 102 Congresso Nazionale della Società Italiana di Fisica (SIF), which was held in Padova in September 2016. On that occasion I presented the observations and the studies made by me and the team from ENEA, Frascati on the subject of “limit cycles” on FTU. Title of the presentation: “MHD limit cycles on FTU”.
For the presentation I gave in Padova, I was assigned the first prize ex aequo for the best oral communication for the section Physics of Matter. I will receive the prize during the next edition of the Congresso Nazionale.
Publications
I realized, together with Dr. Alessandro Cardinali, which was my supervisor for the master degree thesis, a paper on the study of the Lower Hybrid Wave propagation in tokamaks: Casolari, A.; Cardinali, A. Analysis of the Chaotic Behavior of the Lower Hybrid Wave Propagation in Magnetized Plasma by Hamiltonian Theory. Entropy 2016, 18, 175.
I collaborated with Dr. Paolo Buratti, which is my supervisor for the PhD thesis, and colleagues from the FTU team, to write a paper on some diagnostic applications of the measurement of magnetic island rotation velocity:
Buratti, P., Alessi, E., Baruzzo, M., Casolari, A., Giovannozzi, E., Giroud, C., ... & Contributors, J. E. T. (2016). Diagnostic application of magnetic islands rotation in JET. Nuclear Fusion, 56(7), 076004
I'm working on a paper on the subject of “limit cycles”, based on the presentation I gave in Padova, which will be published soon on a special edition of the journal Nuovo Cimento. I'm collaborating with Dr. Paolo Buratti and colleagues from the FTU team on a paper on the subject of “limit cycles” which will be published on the journal Nuclear Fusion. My contribution to this work consists in the numerical simulations I performed and in the interpretation of the numerical results.
