IPAC'23 - Student Poster Session Guide

IPAC’23 / STUDENT POSTER SESSION GUIDE 12 Student Poster Session The ARES linac at DESY is able to provide sub-fs electron bunches and has a range of high-res- olution diagnostic devices installed, such as the PolariX Transverse Defecting Structure, which will allow for performance verification of a new diagnostic. The electron bunches can be altered, allowing for the measurement and analysis of the emitted radiation for different bunch lengths and charges. This work will present the current progress in this area, including the presentation and discussion of simulations, and a discussion of the planned experiments at ARES. SUPM010 Spin polarization simulations in the Future Circular Collider e+e- using Bmad Yi Wu (Ecole Polytechnique Fédérale de Lausanne) . Felix Carlier (Ecole Polytechnique Fédérale de Lausanne), Desmond Barber (Deutsches Elektronen-Syn- chrotron), Eliana Gianfelice-Wendt (Fermi National Accelerator Laboratory), Léon van Riesen-Haupt, Tatiana Pieloni (European Organization for Nuclear Research). Resonant depolarization is a promising method for the high precision centre-of-mass ener- gy calibrations in the Future Circular Collider e+e- (FCC-ee). Spin polarization simulations are needed to validate this method for the FCC-ee. This study offers an early-stage exploration of the FCC-ee spin simulations using Bmad, aiming to guarantee a sufficient polarization level for energy calibrations. Linear and nonlinear spin simulations reveal the impact of lattice imper- fections on spin polarization. Benchmarking studies with SITROS have been performed with the underlying differences being studied. Furthermore, harmonic spin matching has been explored in the FCC-ee using special optics structures to ensure a high polarization level, and simulations for resonant depolarization are under investigation. SUPM011 Study of LHC e-cloud instabilities using the linearised Vlasov method Sofia Johannesson (Ecole Polytechnique Fédérale de Lausanne) . Giovanni Iadarola (Naples University Federico II). Modelling electron cloud driven instabilities using a Vlasov approach enables studying the beam stability on time scales not accessible to conventional Particle In Cell simulation methods. A linear description of electron cloud forces, including the betatron tune modulation along the bunch, is used in the Vlasov approach. This method is benchmarked against macroparticle simulations based on the same linear description of electron cloud forces. Applying high chro- maticity settings is the main mitigation strategy for these instabilities. The effect of chromaticity can be taken into account using the Vlasov method. The Vlasov approach agrees with macro- particle simulations for strong electron clouds, and a stabilizing effect from positive chromati- city can be seen in both approaches. For positive chromaticity, the Vlasov approach shows the existence of weak instabilities which are not observed in the macroparticle simulations. This feature suggests the existence of damping mechanisms that are not captured by the linearized Vlasov equation.