Test of a dispersion sweep correction system using a centroid in the DIRAC beam line

A new proton beam position detector named "centroid" is placed in the DIRAC target situation and is aligned with respect to the beam. Behind it there is a set of various targets used for the DIRAC experiment. The "centroid" itself collects the secondary electrons, which are emitted by the target when hit by the proton beam. This provides an on-line verification of the beam position without obstructing the beam path by a screen, and without perturbing the experiment. A computer application then calculates the corrections needed to centre the beam in both planes as a function of time. This report will explain how this is done

CERN Proton Synchrotron working point control using an improved version of the pole-face-windings and figure-of-eight loop powering

The working point of the CERN Proton Synchrotron, which is equipped with combined function magnets, is controlled using pole-face-windings. Each main magnet consists of one focusing and one de-focusing half-unit on which four pole-face-winding plates are mounted containing two separate coils each, called narrow and wide. At present they are connected in series, but can be powered independently. In addition, a winding called the figure-of-eight loop, contours the pole faces and crosses between the two half units, generating opposite fields in each half-unit. The four optical parameters, horizontal and vertical tune and chromaticity, are adjusted by acting on the pole-face-winding currents in both half units and in the figure-of-eight loop, leaving one physical quantity free. The power supply consolidation project opened the opportunity to use five independent power supplies, to adjust the four parameters plus an additional degree of freedom. This paper presents the results of the measurements that have been made in the five-current mode together with the influence of the magnetic nonlinearities, due to the unbalance in the narrow and wide winding currents, on the beam dynamics

Experimental evidence of adiabatic splitting of charged particle beams using stable islands of transverse phase space

Recently, a novel technique to perform multi-turn extraction from a circular particle accelerator was proposed. It is based on beam splitting and trapping, induced by a slow crossing of a nonlinear resonance, inside stable islands of transverse phase space. Experiments at the CERN Proton Synchrotron started in 2002 and evidence of beam splitting was obtained by summer 2004. In this paper the measurement results achieved with both a low- and a high-intensity, single-bunch proton beam are presented

Damages for Mental Distress Caused by Breach of Contract

内容摘要对在侵权责任中适用精神损害赔偿，无论是在理论界还是司法实务界，都已达成了共识。而对在违约责任中能否适用精神损害赔偿，则众说纷纭、莫衷一是。在我国理论界，对此持否定论的观点占据了主流地位，而在我国司法实务中，一些地方的法院则在一些特定类型的合同之诉中，承认了违约精神损害赔偿的存在。违约可以导致精神损害后果的出现，这是确定不移的事实。那么，反对在违约中给予精神损害赔偿的理由何在？承认违约精神损害赔偿的存在又有何依据？为此，笔者在对精神损害赔偿的功能、法律性质和制度基础等问题作了概述以后，对反对给予违约精神损害赔偿救济的观点一一进行了驳析。并在比较考察国外一些国家的判例和司法实践经验的基础上...ABSTRACT To the application of damages for mental distress in the liability of tore is commonly accepted whether in theory or in practice. However, to the application of damages for mental distress in the liability of breach of contract is not widely accepted. There are many theories exciting now. In theory, most of the people disagree with it. But in our judicatory practice, some courts have ...学位：法律硕士院系专业：法学院法律系_法律硕士(JM)学号：20030817

Nominal LHC Beam Instability Observations in the CERN Proton Synchrotron

The nominal LHC beam has been produced successfully in the CERN Proton Synchrotron since 2003. However, after having restarted the CERN PS in spring 2006, the LHC beam was set-up and observed to be unstable on the 26 GeV/c extraction flat top. An intensive measurement campaign was made to understand the instability and to trace its source. This paper presents the observations, possible explanations and the necessary measures to be taken in order to avoid this instability in the future

Space-Charge Experiments at the CERN Proton Synchrotron

Abstract. Benchmarking of the simulation codes used for the design of the next generation of high beam power accelerators is of paramount importance due to the very demanding requirements on the level of beam losses. This is usually accomplished by comparing simulation results against available theories, and more importantly, against experimental observations. To this aim, a number of well-defined test cases, obtained by accurate measurements made in existing machines, are of great interest. Such measurements have been made in the CERN Proton Synchrotron to probe three space-charge effects: (i) transverse emittance blow-up due to space-charge induced crossing of the integer or halfinteger stop-band, (ii) space-charge and octupole driven resonance trapping, and (iii) intensity-dependent emittance transfer between the two transverse planes. The last mechanism is discussed in detail in this paper and compared to simulation predictions

CERN Proton Synchrotron Complex High-Level Controls Renovation

After a detailed study of the Proton Synchrotron (PS) complex requirements by experts of CERN controls & operation groups, a proposal to develop a new system, called Injector Controls Architecture (InCA), was presented to and accepted by the management late 2007. Aiming at the homogenisation of the control systems across CERN accelerators, InCA is based on components developed for the Large Hadron Collider (LHC) but also new components required to fulfil operation needs. In 2008, the project was in its elaboration phase and we successfully validated its architecture and critical use-cases during several machine development sessions. After description of the architecture put in place and the components used, this paper describes the planning approach taken combining iterative development phases with deployment in operation for validation sessions