Proton Synchrotron | EPFL Graph Search

Le Proton Synchrotron (en français le synchrotron à protons), ou PS, est un accélérateur de particules de type synchrotron situé au CERN près de Genève. C'est le premier synchrotron mis en service au CERN, en 1959. En 2020, il fait maintenant partie de la chaine d'injection du collisionneur à proton LHC. vignette|Plan du complexe d'accélérateurs du CERN. Références Catégorie:Synchrotron Catégorie:Accélérateur lié au CERN

First implementation of transversely split proton beams in the CERN Proton Synchrotron for the fixed-target physics programme

Massimo Giovannozzi, Cedric Jean-François Hernalsteens, Guido Sterbini

A new extraction technique has been studied at the CERN Proton Synchrotron with a view of using it for the fixed-target physics programme at the Super Proton Synchrotron. The extraction scheme is based on advanced concepts of non-linear beam dynamics: prior to extraction a particle beam is split into several beamlets in a transverse plane by crossing a stable resonance, which allows extracting the beamlets over multiple turns. The principle of the extraction, the detail of its implementation, and the progress of the beam commissioning over the years are discussed here. More importantly, the results obtained during the first period of successful use for the physics programme are presented, focusing on the performance analysis of the novel extraction. Copyright CERN. Published by the EPLA under the terms of the Creative Commons Attribution 3.0 License (CC BY). Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Epl Association, European Physical Society2016

First observations of intensity-dependent effects for transversely split beams during multiturn extraction studies at the CERN Proton Synchrotron

Massimo Giovannozzi, Cedric Jean-François Hernalsteens

During the commissioning of the CERN Proton Synchrotron multiturn extraction, tests with different beam intensities were performed in order to probe the behavior of resonance crossing in the presence of possible space charge effects. The initial beam intensity before transverse splitting was varied and the properties of the five beamlets obtained by crossing the fourth-order horizontal resonance were studied. A clear dependence of the beamlets' parameters on the total beam intensity was found, which is the first direct observation of intensity-dependent effects for such a peculiar beam type. The experimental results are presented and discussed in detail in this paper.

American Physical Society2013

Magnetic Model of the CERN Proton Synchrotron

Mariusz Juchno

In this thesis, we present development of the first magnetic model of the main Proton Synchrotron magnets. The operation of the machine and conducting research on increasing its performance require a significant amount of the magnetic field data for the optics modelling. For magnets of the Proton Synchrotron, such amount of data cannot be provided by the magnetic measurements, therefore, we have to rely on magnetic models. We have developed the model based on the numerical analysis of the magnetic field in the magnet and performed the validation with the use of the available magnetic measurements data. The results of the 2D quasi-static analysis were used to decompose the multipolar contributions of different magnet circuits on different levels fo the iron core magnetization within the whole range of the PS operation energies. Established formulas of every circuit contributions take into account the global magnetization of the yoke and its saturation as well as a local magnetization changes caused by contributions of other circuits. The 3D numerical analysis was setup to study the influence of the magnet stray field and gaps between the magnet blocks on the integrated multipolar field. Its results were used to derive appropriate model corrections of the integrated multipolar field with respect to the field in the reference cross-section and to approximate the effective magnetic lengths of the auxiliary circuits of the PS magnet. In order to perform a non-linear chromaticity analysis and to take the full advantage of the developed model, we have modified the existing optics model of the PS lattice. We have integrated magnetic model into the optics calculation with two simulation adjustment methods, which optimize the main coil current in similar way as it is done for the real magnets and adjust four free parameters to match the measured parameters of the initial working point. We have successfully validated the combined magnetic and optics models for various beam momentum levels and magnet powering conditions. With the use of the new magnetic model, for the first time in the history of the PS we are able to predict a higher-order chromaticity function for any energy. Base on the optics modelling results, we have derived working point transfer matrices for the non-linear chromaticity, which allow to predict a set of powering current offsets required to apply foreseen working point adjustment. We were also able to model an offset of the measured transfer matrices due to a change of the radial position chosen for the beam production.

EPFL2013

Magnetic Model of the CERN Proton Synchrotron

Mariusz Juchno

EPFL2013