Pàgines 20-22, 68, 84-86, 185, 204-205, 209-210, 213-241 en blanc, no hi fuguren. / During last four or five decades there has been a growing demand in particle accelerators which can provide electron beams in the energy ranging from 2 MeV to 100 MeV with high energy resolution and good dose control. Other important requirements are that the machines must be compact, of low power consumption, low price and relatively low maintenance cost. There is a variety of sectors interested in such particle accelerators ranging from industry (industrial radiography) to nuclear physics experiments. One type of machines that meet all these requirements are the electron accelerators with beam recirculation. Fair representatives of this class of accelerators are race-track microtrons (RTM). These sources of electron beam are the most efficient equipment for applications with a relatively low beam current and medium energies ranging from 2 MeV to 100 MeV.
The aim of the present thesis is to perform studies of some aspects of the RTMs. One part of the thesis is devoted to the design and development of magnetic elements with permanent magnets of two RTMs for different applications. The first one, which is currently under construction at the UPC (Universidad Politécnica de Cataluña), is a novel accelerator with the beam energy variable between 6 MeV and 12 MeV for medical applications (Intraoperative Radiation Therapy treatments). The other machine is a 55 MeV RTM for the detection of explosives by means of photonuclear reactions, which is at the stage of tests at the Skobeltsyn Institute of Nuclear Physics (SINP). The magnetic field in the designed magnets is generated by rare earth permanent magnet (REPM) materials. This allows to get quite compact magnetic systems compatible with high vacuum environment. In the thesis the design and magnetic properties characterization of the magnetic system of these RTMs are carried out. The calculations were performed by means of 2D and 3D simulations using the POISSON, FEMM and ANSYS codes. In the case of the UPC RTM the design of the 180º dipoles, extraction magnets and quadrupole magnet are carried out. For the SINP 55 MeV RTM the optimization of the magnetic field shielding with the aim to reduce the stray magnetic field generated by the extraction magnet is presented. The results of the simulations were confirmed by experimental measurements of the magnetic field of the magnet with the optimized magnetic field shielding.
In the other part of the thesis some aspects of the beam dynamics in RTM magnetic systems are studied. A detailed analysis of the fringe - field focusing in RTM dipole magnets is carried out. Equations for calculation of the fringe - field effect on electron beam trajectories are derived and are applied for a study of the end magnets of the UPC 12 MeV RTM. A general formalism for describing the longitudinal beam dynamics in RTMs for electron beams with arbitrary energy and end magnets with arbitrary magnetic field profile is also developed. This formalism is used for the calculation of the phase-slip effect in RTMs with low energy injection.
| Identifer | oai:union.ndltd.org:TDX_UPC/oai:www.tdx.cat:10803/128671 |
| Date | 09 October 2013 |
| Creators | Rigla Pérez, Juan Pablo |
| Contributors | Koubychine, Yuri, Universitat Politècnica de Catalunya. Institut de Tècniques Energètiques |
| Publisher | Universitat Politècnica de Catalunya |
| Source Sets | Universitat Politècnica de Catalunya |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/doctoralThesis, info:eu-repo/semantics/publishedVersion |
| Format | 205 p., application/pdf |
| Source | TDX (Tesis Doctorals en Xarxa) |
| Rights | info:eu-repo/semantics/openAccess, ADVERTIMENT. L'accés als continguts d'aquesta tesi doctoral i la seva utilització ha de respectar els drets de la persona autora. Pot ser utilitzada per a consulta o estudi personal, així com en activitats o materials d'investigació i docència en els termes establerts a l'art. 32 del Text Refós de la Llei de Propietat Intel·lectual (RDL 1/1996). Per altres utilitzacions es requereix l'autorització prèvia i expressa de la persona autora. En qualsevol cas, en la utilització dels seus continguts caldrà indicar de forma clara el nom i cognoms de la persona autora i el títol de la tesi doctoral. No s'autoritza la seva reproducció o altres formes d'explotació efectuades amb finalitats de lucre ni la seva comunicació pública des d'un lloc aliè al servei TDX. Tampoc s'autoritza la presentació del seu contingut en una finestra o marc aliè a TDX (framing). Aquesta reserva de drets afecta tant als continguts de la tesi com als seus resums i índexs. |
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