Time resolved spectrometry on the CLIC Test Facility 3

The high charge (>6ìC) electron beam produced in the CLIC Test Facility 3 (CTF3) is accelerated in fully beam loaded cavities. To be able to measure the resulting strong transient effects, the time evolution of the beam energy and its energy spread must be determined with at least 50MHz bandwidth. Three spectrometer lines are installed along the linac in order to control and tune the beam. The electrons are deflected by dipole magnets onto Optical Transition Radiation (OTR) screens which are observed by CCD cameras. The measured horizontal beam size is then directly related to the energy spread. In order to provide time-resolved energy spectra, a fraction of the OTR photons is sent onto a multi-channel photomultiplier. The overall setup is described, special focus is given to the design of the OTR screen with its synchrotron radiation shielding. The performance of the time-resolved measurements are discussed in detail. Finally, the limitations of the system, mainly due to radiation problems are discussed

Longitudinal beam profile measurements at CTF3 using a streak camera

The proposed Compact Linear Collider (CLIC) is a multi-TeV electron-positron collider for particle physics based on an innovative two-beam acceleration concept. A high-intensity drive beam powers the main beam of a high-frequency (30 GHz) linac with a gradient of 150 MV/m, by means of transfer structure sections. The aim of the CLIC Test Facility (CTF3) is to make exhaustive tests of the main CLIC parameters and to prove the technical feasibility. One of the points of particular interest is the demonstration of bunch train compression and combination in the Delay Loop and in the Combiner Ring. Thus, detailed knowledge about the longitudinal beam structure is of utmost importance and puts high demands on the diagnostic equipment. Among others, measurements with a streak camera have been performed on the linac part of the CTF3 as well as on the newly installed Delay Loop. This allowed e.g. monitoring of the longitudinal structure of individual bunches, the RF combination of the beam, the behavior during phase shifts and the influence of the installed wiggler. This article first gives an overview of the CTF3 facility, then describes in detail the layout of the long optical lines required for observation of either optical transition radiation or synchrotron radiation, and finally shows first results obtained during the last machine run this year

Beam Dynamics and First Operation of the Sub-Harmonic Bunching System in the CTF3 Injector

The CLIC Test Facility 3 (CTF3), built at CERN by an international collaboration, aims at demonstrating the feasibility of the CLIC scheme by 2010. The CTF3 drive beam generation scheme relies on the use of a fast phase switch of a sub-harmonic bunching system in order to phase-code the bunches. The amount of charge in unwanted satellite bunches is an important quantity, which must be minimized. Beam dynamic simulations have been used to study the problem, showing the limitation of the present CTF3 design and the gain of potential upgrades. In this paper the results are discussed and compared with beam measurements taken during the first operation of the system

The Rights Design and Systems Construction on the Traditional Knowledge Protection： Focused on the Intellectual Property Rights

当前的国内、国际形势及实践已经表明，变革现行的知识产权制度，探索和创设传统知识私权保护机制具有十分重要的理论和现实意义。本论文从传统知识保护对象界定入手，以传统知识保护的正当性基础、制度条件、权利体系分析为过渡，以利益平衡为主轴，加入传统知识保护与知识产权制度的融合这一润滑剂，最终落脚于传统知识保护的制度构架。 本论文对传统知识的研究采用广义的定义方法。论文在尊重传统知识多样性、多层性、开放性的同时，探寻可能影响权利设计及制度构建的传统知识特性，并认为这些特性不是根本性导致知识产权制度无法提供保护的因素，而是将影响知识产权制度变革和拓展的多样性文化构成。传统知识的文献化对于传统知识保护具有重...In recent years，there have been increasing theoretical and practical significances in the subject that how to change the existing intellectual property systems , and how to innovate and create the new systems to protect traditional knowledge. Beginning form the definition of traditional knowledge, this article revolves round the core of interest-balancing, analyzes justifiability, conditions and r...学位：法学博士院系专业：法学院法律系_民商法学(含劳动法学、社会保障法学)学号：1202005140281

Discussion on Research and Development of Local Documents Exchange Platform

地方文献是一个地方政治、经济、文化和社会事业发展以及历史、风俗、资源等方面的文献资料.它具有区域性、史料性、广泛性和时代性等特点，地方文献与一般文献的最主要区别在于其具有地方特色。因此，它是目前国内外图书馆界公认的重要文献资源之一。但是由于各地方图书馆在地方文献的收集标准、范围上并没有达成共识，收集重点也不明确。在地方文献保管上，除少数图书馆是设专库集中收藏外，绝大多数馆是分散在各个书库之中；在数据库建设方面缺乏统筹规划，处于一种无序的、各自为政的状态。因此，必须加强地方文献信息资源共享建设，使之更好的促进社会的发展，而传统的地方文献资源共享的方式主要有：建立联合目录与进行合作编目、馆际互借、...Local documents are a local political, economic, cultural and social undertakings development and the history, customs, resources and other aspects of documents. It has the characteristics of regional, historical data, universality and times. The most important differences between local documents and general documents is that local documents has its local characteristics. Therefore, it is one of t...学位：工学硕士院系专业：图书馆_计算机技术学号：X200822102

A high-gradient test of a 30 GHz copper accelerating structure

The CLIC study is investigating a number of different materials at different frequencies in order to find ways to increase achievable accelerating gradient and to understand what are the important parameters for high-gradient operation. So far a series of rf tests have been made with a set of identical-geometry 30 GHz and X-band structures in copper, tungsten and molybdenum. A new test of a 30 GHz copper accelerating structure has been completed in CTF3 with pulse lengths up to 70 ns. The new results are presented and compared to the previous structures to determine dependencies of quantities such accelerating gradient, material, frequency, pulse length, conditioning rate, breakdown rate and surface damage

A High-Gradient Test of a 30 GHz Molybdenum-Iris Structure

The CLIC study is actively investigating a number of different materials in an effort to find ways to increase achievable accelerating gradient. So far a series of rf tests have been made with a set of identical-geometry structures: a W-iris 30 GHz structure, a Mo-iris 30 GHz structure (with pulses as long as 16 ns) and a scaled Mo-iris X-band structure. A second Mo-iris 30 GHz structure of the same geometry has now been tested in CTF3 with pulse lengths up to 350 ns. The structure was conditioned to a gradient of 140 MV/m with a 70 ns pulse length and a breakdown rate slope of 13 MV/m per decade has been measure

Driving term experiments at CERN

19 pages, 33 figures.-- PACS nrs.: 41.85.-p, 29.27.-a, 05.45.-a.-- ISI Article Identifier: 000245810500010Driving Term experiments have been performed both at small [PS (Proton Synchrotron) Booster] and large accelerators [SPS (Super Proton Synchrotron)] at CERN. The theory of how to measure driving terms is reviewed. A wealth of SPS experiments is shown together with a successful comparison with model calculations. The PS Booster studies aimed at optimizing the machine performance by measuring and correcting selected driving terms.Peer reviewe

Driving term experiments at CERN

Driving Term experiments have been performed both at small [PS (Proton Synchrotron) Booster] and large accelerators [SPS (Super Proton Synchrotron)] at CERN. The theory of how to measure driving terms is reviewed. A wealth of SPS experiments is shown together with a successful comparison with model calculations. The PS Booster studies aimed at optimizing the machine performance by measuring and correcting selected driving terms

Driving term experiments at CERN

Driving Term experiments have been performed both at small [PS (Proton Synchrotron) Booster] and large accelerators [SPS (Super Proton Synchrotron)] at CERN. The theory of how to measure driving terms is reviewed. A wealth of SPS experiments is shown together with a successful comparison with model calculations. The PS Booster studies aimed at optimizing the machine performance by measuring and correcting selected driving terms