In the Large Hadron Collider (LHC), particle physics events are created by colliding high energy proton beams at a number of interaction points around the ring. One of the main performance indicating parameters of the LHC is the luminosity. The luminosity is limited by, amongst other things, the strength of the beam-beam interaction. In this thesis, the effect of the beam-beam interaction on the luminosity performance of the LHC and the proposed High Luminosity Large Hadron Collider (HL-LHC) is investigated. Results from a number of dedicated, long-range beam-beam machine studies are presented and analysed. In these studies, the minimum beam-beam separation for two different beta star— optics are identified. This separation defines the minimum operational crossing angle in the LHC. The data from these studies are then compared to simulation of the dynamic aperture and the results are discussed. In addition to studies of the LHC, an analytical approach is derived in order to describe the hourglass effect, which may become a contributing factor in limiting the luminosity performance of the HL-LHC.

Orientador: Eduardo Granado Monteiro da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-19T18:24:03Z (GMT). No. of bitstreams: 1 Marcondes_RafaelJoseFranca_M.pdf: 4781078 bytes, checksum: 963ca375d793021d73e27eaf311966c2 (MD5) Previous issue date: 2012 / Resumo: Um novo anel de armazenamento de elétrons está sendo projetado para a produção de luz síncrotron de alto brilho no Laboratório Nacional de Luz Síncrotron (LNLS), em Campinas. Para atingir um alto brilho, requer-se uma forte focalização do feixe, levando a fortes não-linearidades dos campos magnéticos, o que limita a região de estabilidade do movimento dos elétrons. Neste trabalho, estudamos a dinâmica destas partículas no anel e aplicamos métodos para a otimização da abertura dinâmica / Abstract: A new electron storage ring, Sirius, is being designed for the production of high brightness synchrotron light at the Brazilian Synchrotron Light Laboratory (LNLS), in Campinas. To achieve high brightness, strong focusing of the beam is required, leading to strong non-linearities in the magnetic elds, which limit the region of stable motion of the electrons. In this work we study the dynamics of these particles in the ring and apply methods for the optimisation of the dynamic aperture / Mestrado / Mestre em Física

A study is undertaken of the numerical reconstruction of acoustic and electromagnetic (EM) localized waves (LWs). The latter are carrier-free ultra-wideband pulses characterized by large focusing depths and extended ranges of localization. Special emphasis is placed on finite energy LWs that can be generated by dynamic aperture antennas with independently addressable elements. The reconstruction techniques are based on Huygens and Rayleigh-Sommerfeld integral I and II representations, both in the time and frequency domains. In contradistinction to the Weyl representation,they lend themselves to the physical realization of space-time aperture sources capable of generating localized wave solutions propagating away from the aperture plane. A detailed comparison of the three reconstruction techniques has been carried out in connection with LW solutions to the scalar wave equation, especially with respect to their handling of acausal components incorporated in the aperture excitation fields. In addition, a study is presented of the characteristic properties of LWs propagating through dispersive media modeled by the Klein-Gordon equation. It is demonstrated that contrary to expectation, the depletion of the spectral components of the LW Klein-Gordon field may be slower than that associated with the free space scalar field. Previous work by Power et al. [73] is extended by studying the acoustic bistatic scattering of a modified power spectrum (MPS) pulse from rigid and compressible spheres. The analysis allows the extraction of the radius of a sphere from the backscattered data. Finally, a special class of electromagnetic (EM) LWs, referred to as azimuthally polarized X waves (APXWs), is derived and their reconstruction is addressed, both in the time and frequency domains. / Ph. D.