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This paper starts with an introduction to some elements of physical kinetics relevant to microscopic interactions in gas or plasma systems. The aim is to provide the necessary background for understanding charged particle beams. Emphasis is placed on the important role played by collisions in plasmas. We then give a detailed, albeit non-exhaustive, review of intrabeam scattering (IBS), which consists of the study of diffusion effects caused by multiple Coulomb scattering on charged particle beams, in both the transverse and the longitudinal beam dimensions. Finally, applications to the large hadron collider 7 TeV stored proton beam and the ’Extra Low Energy Antiproton’ (ELENA) 100 keV decelerated antiproton beam are used to illustrate the behaviour of the IBS growth rates, for a high-energy storage ring well above the transition energy and an ultra-low-energy decelerator ring below the transition energy., CERN Yellow Reports: School Proceedings, Vol 3 (2017): Proceedings of the CAS-CERN Accelerator School on Intensity Limitations in Particle Beams

II Jornadas Latino-Americanas de Linguagens e Cultura. Em comemoração aos 100 anos de nascimento de Roa Bastos e 50 anos da morte de Guimarães Rosa Duas das maiores representantes da literatura de autoria feminina da América Latina são Rachel de Queiroz e Isabel Allende, sobretudo, pelo sucesso de público e crítica de suas obras Memorial de Maria Moura e La casa de los espiritus. Neste estudo, pretendemos investigar comparativamente a representação imaginária das protagonistas dessas obras, Maria Moura e Clara, procurando investigar semelhanças e diferenças na construção da imagem da mulher nos contextos patriarcais representados nas obras Programa de Pós-Graduação em Literatura Comparada Programa de Pós-Graduação Interdisciplinar em Estudos Latino-Americanos Curso de Graduação em Letras – Artes e Mediação Cultural

Intra Beam Scattering (IBS) is expected to be the main performance limitation of the Extra Low Energy Antiproton ring (ELENA), a small synchrotron equipped with electron cooling under construction at CERN to decelerate antiprotons from 5.3 MeV to 100 keV. Thus, the duration of the ramps must not be too long to avoid excessive blow up due to IBS. On the other hand, the bending magnets are C-shaped and the vacuum chambers are without insulated junctions, which are difficult for fully baked machines; thus, the ramps must not be too short. The evolution of transverse and longitudinal emittances along the ramps have been estimated assuming that IBS is the main phenomenon leading to blow-up. The blow-up due to IBS found along the ramps have been found to be acceptable., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The European Spallation Source (ESS) is a research center based on the world’s most powerful proton driver, 2.0 GeV, 5 MW on target, currently under construction in Lund. With an increased pulse frequency, the ESS linac could deliver additional beam pulses to a neutrino target, thus giving an excellent opportunity to produce a high-performance ESS neutrino Super-Beam (ESSnuSB). The focusing system surrounding the neutrino target requires short proton pulses. An accumulator ring and acceleration of an H⁻ beam in the linac for charge-exchange injection into the accumulator could provide such short pulses. In this paper we present an overview of the work with optimizing the accumulator design and the challenges of injecting and storing 1.10¹⁵ protons per pulse from the linac. In particular, particle tracking simulations with space charge will be described., Proceedings of the 57th ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams, HB2016, Malmö, Sweden

It is proposed to use the 2.0 GeV, 5 MW proton linac, 2.86 ms long pulses at 14 Hz of the European Spallation Source [1], [2] being built in Lund, Sweden to deliver, alternately with the spallation neutron production a very intense neutrino beam to enable the discovery of leptonic CP violation. To this end the linac would be upgraded to supply, in addition to the 2.86 ms long proton pulses at 14 Hz, four 0.72 ms H􀀀 short pulses at 70 Hz for neutrino production. Because of the high current required in the pulsed neutrino horn, the length of the pulses used for neutrino production will need to be compressed to a few s with the aid of an accumulator ring. Charge exchange injection of an H- beam from the linac will be used, the linac delivering 1.1E15 H- per pulse. This paper is about stripping foil heating considerations, emphasizing the detailed evaluation of the foil temperature over the multiple ring re-fills

The European Spallation Source (ESS) is a research center based on the world's most powerful neutron source currently under construction in Lund, Sweden. 2.0 GeV, 2.86 ms long proton pulses at 14 Hz are produced for the spallation facility (5MW on target). The possibility to pulse the linac at higher frequency to deliver, in parallel with the spallation neutron production, a very intense, cost effective, high performance neutrino beam. Short pulses on the target require an accumulator ring. The optimization of the accumulator lattice to store these high intensity beams from the linac (1.1x10¹⁵ protons per pulse) has to take into account the space available on the ESS site, transport of H⁻ beams (charge exchange injection), radiation and shielding needs. Space must be available in the ring for collimation and an RF system for the extraction gap and loss control. We present the status of the accumulator for ESS neutrino facility., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

The European Spallation Source (ESS) is a research center based on the world’s most powerful neutron source currently under construction in Lund, Sweden. 2.0 GeV, 2.86 ms long proton pulses at 14 Hz are produced for the spallation facility (5MW on target). The possibility to pulse the linac at higher frequency to deliver, in parallel with the spallation neutron production, a very intense, cost effective and high performance neutrino beam. Short pulses on the target require an accumulator ring. The optimization of the accumulator lattice to store these high intensity beams from the linac (1.1E15 protons per pulse) has to take into account the space available on the ESS site, transport of H− beams (charge exchange injection), radiation and shielding needs. Space must be available in the ring for collimation and an RF system for the extraction gap and loss control. We present the status of the accumulator for the ESS neutrino facility.

The CERN PS Booster will be upgraded with an H⁻ injection system. The chicane magnets for the injection bump ramp-down in 5 ms and generate eddy currents in the inconel vacuum chamber which perturb the homogeneity of the magnetic field. The multipolar field components are extracted from 3D OPERA simulations and are included in the lattice model. The beta-beating correction is computed all along the ramp and complete tracking simulations including space-charge are performed to evaluate the impact of these perturbations and their correction., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The European Spallation Source (ESS) is a research centre based on the world’s most powerful neutron source currently under construction in Lund, Sweden, using 2.0 GeV, 2.86 ms long proton pulses at 14 Hz for the spallation facility (5MW on target). The possibility to pulse the linac at 28 Hz to deliver, in parallel with the spallation neutron production, a very intense, cost effective, high performance neutrino beam. The high current in the horns of the target system for the neutrino production requires proton pulses far shorter than the linac pulse. Therefore an accumulator ring is required after the linac to produce the shorter pulses. Charge exchange injection of an H⁻ beam from the linac would be used. The Linac would deliver 1.1 10¹⁵ protons per pulse. Due to space charge limits, several rings or one ring re-filled several times during the neutrino cycle are necessary. A cost effective design of an accumulator that can handle this large number of ions will be shown, taking into account the structure of the linac pulse and the requirements of the target system. Beam dynamics issues, the injection system, the extraction and the distribution on the targets are addressed., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

We discuss the design of the muon capture front end of a neutrino factory and present studies of variations of its components. In the front end, a proton bunch on a target creates secondary pions that drift into a capture transport channel, decaying into muons. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. The cooling section uses absorber material (reducing the 3-D muon momenta) alternating with rf cavities (restoring longitudinal momentum) within strong focusing magnetic fields. The design is affected by limitations on accelerating gradients within magnetic fields. The effects of gradient limitations are explored, and mitigation strategies are presented. Variations of the ionization cooling and acceleration scenarios and extensions toward use in a muon collider are discussed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

This report sums up in two volumes the first 50 years of operation of the CERN Proton Synchrotron. After an introduction on the genesis of the machine, and a description of its magnet and powering systems, the first volume focuses on some of the many innovations in accelerator physics and instrumentation that it has pioneered, such as transition crossing, RF gymnastics, extractions, phase space tomography, or transverse emittance measurement by wire scanners. The second volume describes the other machines in the PS complex: the proton linear accelerators, the PS Booster, the LEP pre-injector, the heavy-ion linac and accumulator, and the antiproton rings.

The performance of the CERN PS Booster (PSB) synchrotron is believed to be limited mainly by direct space charge effects at low energy. The main motivation to construct Linac4 is to raise the PSB injection energy to mitigate direct space charge effects. At present, simulation of the injection and the ow energy part of the cycle aim at defining Investigations on the influence of parameters of the injected beam on the performance of the PSB are described., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Due to the high bunch density, the output emittances of the CLIC Damping Rings (DR) are strongly dominated by the effect of Intrabeam Scattering (IBS). In an attempt to optimize the ring design and using classical IBS formalisms and approximations, the scaling of the extracted emittances and IBS growth rates is being studied, with respect to several ring parameters including energy, bunch charge, optics and wiggler characteristics. Results from the simulations using a multi-particle tracking code are also presented., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The CLIC 3 TeV nominal design requires very low emittance of the electron and positron beams to be reached in the damping rings. Due to low energy and to relatively high bunch charge and ultra-low emittance, Intra-Beam Scattering (IBS) effect is very strong and an accurate calculation is needed to check if the required emittance is effectively reached. For this reason it is being developed at CERN a new Software for IBS and Radiation Effects (SIRE), which simulates the evolution of the beam particle distribution in the damping rings, taking into account radiation damping, IBS and quantum excitation. In this paper we present the results of our simulations performed with SIRE on the current lattice of the CLIC damping rings., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

We discuss alternative designs of the muon capture front end of the Neutrino Factory International Design Study (IDS). In the front end, a proton bunch on a target creates secondary pions that drift into a capture channel, decaying into muons. A sequence of RF cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. This design is affected by limitations on accelerating gradients within magnetic fields. The effects of gradient limitations are explored, and mitigation strategies are presented., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan