WorldWideScience

Sample records for clic nano-stabilization studies

  1. Spectrometers for RF breakdown studies for CLIC

    Science.gov (United States)

    Jacewicz, M.; Ziemann, V.; Ekelöf, T.; Dubrovskiy, A.; Ruber, R.

    2016-08-01

    An e+e- collider of several TeV energy will be needed for the precision studies of any new physics discovered at the LHC collider at CERN. One promising candidate is CLIC, a linear collider which is based on a two-beam acceleration scheme that efficiently solves the problem of power distribution to the acceleration structures. The phenomenon that currently prevents achieving high accelerating gradients in high energy accelerators such as the CLIC is the electrical breakdown at very high electrical field. The ongoing experimental work within the CLIC collaboration is trying to benchmark the theoretical models focusing on the physics of vacuum breakdown which is responsible for the discharges. In order to validate the feasibility of accelerating structures and observe the characteristics of the vacuum discharges and their eroding effects on the structure two dedicated spectrometers are now commissioned at the high-power test-stands at CERN. First, the so called Flashbox has opened up a possibility for non-invasive studies of the emitted breakdown currents during two-beam acceleration experiments. It gives a unique possibility to measure the energy of electrons and ions in combination with the arrival time spectra and to put that in context with accelerated beam, which is not possible at any of the other existing test-stands. The second instrument, a spectrometer for detection of the dark and breakdown currents, is operated at one of the 12 GHz stand-alone test-stands at CERN. Built for high repetition rate operation it can measure the spatial and energy distributions of the electrons emitted from the acceleration structure during a single RF pulse. Two new analysis tools: discharge impedance tracking and tomographic image reconstruction, applied to the data from the spectrometer make possible for the first time to obtain the location of the breakdown inside the structure both in the transversal and longitudinal direction thus giving a more complete picture of the

  2. The physics benchmark processes for the detector performance studies used in CLIC CDR Volume 3

    CERN Document Server

    Allanach, B.J.; Desch, K.; Ellis, J.; Giudice, G.; Grefe, C.; Kraml, S.; Lastovicka, T.; Linssen, L.; Marschall, J.; Martin, S.P.; Muennich, A.; Poss, S.; Roloff, P.; Simon, F.; Strube, J.; Thomson, M.; Wells, J.D.

    2012-01-01

    This note describes the detector benchmark processes used in volume 3 of the CLIC conceptual design report (CDR), which explores a staged construction and operation of the CLIC accelerator. The goal of the detector benchmark studies is to assess the performance of the CLIC ILD and CLIC SiD detector concepts for different physics processes and at a few CLIC centre-of-mass energies.

  3. A 12 GHZ RF Power source for the CLIC study

    CERN Document Server

    Peauger, F; Curt, S; Doebert, S; McMonagle, G; Rossat, G; Schirm, KM; Syratchev, I; Timeo, L; Kuzikhov, S; Vikharev, AA; Haase, A; Sprehn, D; Jensen, A; Jongewaard, EN; Nantista, CD; Vlieks, A

    2010-01-01

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  4. Status of the Fatigue Studies on the CLIC Accelerating Structures

    CERN Document Server

    Calatroni, S; Neupert, H; Wuensch, Walter; CERN. Geneva

    2006-01-01

    The need for high accelerating gradients for the future multi-TeV e+e- Compact Linear Collider (CLIC) imposes considerable constraints on the materials of the accelerating structures. The surfaces exposed to high pulsed RF (Radio Frequency) currents are subject to cyclic thermal stresses which are expected to induce surface break up by fatigue. Since no fatigue data exists in the literature up to very large numbers of cycles and for the particular stress pattern present in RF cavities, a comprehensive study of copper alloys in this parameter range has been initiated. Fatigue data for selected copper alloys in different states are presented

  5. Feasibility study of multipoint based laser alignment system for CLIC

    CERN Document Server

    Stern, G; Mainaud-Durand, H; Piedigrossi, D; Geiger, A

    2012-01-01

    CLIC (Compact LInear Collider) is a study for a future electron-positron collider that would allow physicists to explore a new energy region beyond the capabilities oftoday’s particle accelerators. Alignment is one of the major challenges within the CLIC study in order to achieve the high requirement of a multi-TeV center of mass colliding beam energy range (nominal 3 TeV). To reach this energy in a realistic and cost efficient scenario all accelerator components have to be aligned with an accuracy of 10 μm over a sliding window of 200 m. The demand for a straight line reference is so far based on stretched wires coupled with Wire Positioning Sensors (WPS). These solutions are currently further developed inorder to reduce the drawbacks which are mainly given by their costs and difficult implementation. However, it should be validated through inter-comparison with a solution ideally based on a different physical principle. Therefore, a new metrological approach is proposed using a laser beam as straight lin...

  6. The CERN study of a 2 TeV e+e- collider CLIC

    International Nuclear Information System (INIS)

    Progress with the CERN study of a 2 TeV e+e- linear collider (CLIC) is reported. The CLIC Test Facility for drive beam generation is giving first results. Results are also reported from development work on 30 GHz prototype accelerating structures (including RF quadrupole configurations) from a 30 GHz transfer structure for RF power generation in the CLIC two-beam scheme, from a prototype system for submicron automatic alignment and from theoretical work on wake-field stabilization, alignment tolerances, compensation of the beams energy spread and the final focus system

  7. CLIC Drive Beam Phase Stabilisation

    CERN Document Server

    Gerbershagen, Alexander; Schulte, Daniel

    The thesis presents phase stability studies for the Compact Linear Collider (CLIC) and focuses in particular on CLIC Drive Beam longitudinal phase stabilisation. This topic constitutes one of the main feasibility challenges for CLIC construction and is an essential component of the current CLIC stabilisation campaign. The studies are divided into two large interrelated sections: the simulation studies for the CLIC Drive Beam stability, and measurements, data analysis and simulations of the CLIC Test Facility (CTF3) Drive Beam phase errors. A dedicated software tool has been developed for a step-by-step analysis of the error propagation through the CLIC Drive Beam. It uses realistic RF potential and beam loading amplitude functions for the Drive and Main Beam accelerating structures, complete models of the recombination scheme and compressor chicane as well as of further CLIC Drive Beam modules. The tool has been tested extensively and its functionality has been verified. The phase error propagation at CLIC h...

  8. Studies on the thermo-mechanical behavior of the CLIC two-beam module

    CERN Document Server

    Nousiainen, R; Österberg, K

    2010-01-01

    To fulfil the mechanical requirements set by the luminosity goals of the CLIC collider, currently under study, the 2-m two-beam modules, the shortest repetitive elements in the main linac, have to be controlled at micrometer level. At the same time these modules are exposed to variable high power dissipation while the accelerator is ramped up to nominal power as well as when the mode of CLIC operation is varied. This will result into inevitable temperature excursions driving mechanical distortions in and between different module components. A FEM model is essential to estimate and simulate the fundamental thermo-mechanical behaviour of the CLIC two-beam module to facilitate its design and development. In this paper, the fundamental thermal environments for the RF-components of the module are described. Also the thermal and structural results for the studied module configuration are presented showing the fundamental thermo-mechanical behaviour under the main CLIC collider operation conditions.

  9. CLIC PHYSICS OVERVIEW

    CERN Document Server

    Bozovic-Jelisavcic, Ivanka

    2016-01-01

    In this paper, based on the invited talk at the 17th Lomonosov Conference of Elementary Particle Physics, the physics program at the future Compact Linear Collider (CLIC) will be reviewed, with particular emphasis on the Higgs physics studies. It will be demonstrated, on the basis of detailed physics and detector studies carried out at CLIC, that the CLIC is indeed a precision tool for studies both in the Higgs sector and beyond the Standard Model.

  10. Preparing for CLIC tests

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    The Canon 5 undergoes first brazing for preparation in the CLIC study at the CLIC Test Facility 2 (CTF2). This will test injection for a proposed linear collider that will further explore discoveries made at the LHC. Electric fields in the canon will boost electrons into the acceleration fields of the collider.

  11. CLIC and CTF3

    CERN Document Server

    Tecker, F

    2008-01-01

    The CLIC study has been exploring the scheme for an electron-positron Collider (CLIC) with high luminosity (10$^{34}$ - 10$^{35}$ cm2/s) and a nominal centre-of-mass energy of 3 TeV in order to make the multi-TeV range accessible for physics. The CLIC Test Facility CTF3, built at CERN by an international collaboration, aims at demonstrating the feasibility of the CLIC scheme by 2010. CTF3 consists of a 150 MeV electron linac followed by a 42 m long delay loop and an 84 m combiner ring, followed by a two-beam test stand and a test decelerator. The linac and delay loop have been previously commissioned, while the combiner ring has been recently completed. After a presentation of the recent CLIC parameters, the status of the test facility, the experimental results achieved and the future plans will be presented.

  12. Detector optimization studies and light Higgs decay into muons at CLIC

    International Nuclear Information System (INIS)

    The Compact Linear Collider (CLIC) is a concept for a future e+e- linear collider with a center-of-mass energy of up to 3 TeV. The design of a CLIC experiment is driven by the requirements related to the physics goals, as well as by the experimental conditions. For example, the short time between two bunch crossings of 0.5 ns and the backgrounds due to beamstrahlung have direct impact on the design of a CLIC experiment. The Silicon Detector (SiD) is one of the concepts currently being discussed as a possible detector for the International Linear Collider (ILC). In this thesis we develop a modified version of the SiD simulation model for CLIC, taking into account the specific experimental conditions. In addition, we developed a software tool to investigate the impact of beam-related backgrounds on the detector by overlaying events from different simulated event samples. Moreover, we present full simulation studies, determining the performance of the calorimeter and tracking systems. We show that the track reconstruction in the all-silicon tracker of SiD is robust in the presence of the backgrounds at CLIC. Furthermore, we investigate tungsten as a dense absorber material for the hadronic calorimeter, which allows for the construction of a compact hadronic calorimeter that fulfills the requirements on the energy resolution and shower containment without a significant increase of the coil radius. Finally, the measurement of the decays of light Higgs bosons into two muons is studied in full simulation. We find that with an integrated luminosity of 2 ab-1, corresponding to 4 years of data taking at CLIC, the respective Higgs branching ratio can be determined with a statistical uncertainty of approximately 15%.

  13. Detector optimization studies and light Higgs decay into muons at CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Grefe, Christian

    2013-09-15

    The Compact Linear Collider (CLIC) is a concept for a future e{sup +}e{sup -} linear collider with a center-of-mass energy of up to 3 TeV. The design of a CLIC experiment is driven by the requirements related to the physics goals, as well as by the experimental conditions. For example, the short time between two bunch crossings of 0.5 ns and the backgrounds due to beamstrahlung have direct impact on the design of a CLIC experiment. The Silicon Detector (SiD) is one of the concepts currently being discussed as a possible detector for the International Linear Collider (ILC). In this thesis we develop a modified version of the SiD simulation model for CLIC, taking into account the specific experimental conditions. In addition, we developed a software tool to investigate the impact of beam-related backgrounds on the detector by overlaying events from different simulated event samples. Moreover, we present full simulation studies, determining the performance of the calorimeter and tracking systems. We show that the track reconstruction in the all-silicon tracker of SiD is robust in the presence of the backgrounds at CLIC. Furthermore, we investigate tungsten as a dense absorber material for the hadronic calorimeter, which allows for the construction of a compact hadronic calorimeter that fulfills the requirements on the energy resolution and shower containment without a significant increase of the coil radius. Finally, the measurement of the decays of light Higgs bosons into two muons is studied in full simulation. We find that with an integrated luminosity of 2 ab{sup -1}, corresponding to 4 years of data taking at CLIC, the respective Higgs branching ratio can be determined with a statistical uncertainty of approximately 15%.

  14. The 30 GHz transfer structure for the CLIC study

    CERN Document Server

    Carron, G; Thorndahl, L

    1998-01-01

    In the so-called "Two-Beam Acceleration Scheme" the energy of a drive beam is converted to rf power by means of a "Transfer Structure", which plays the role of power source. In the Transfer Structure the bunched drive beam is decelerated by the electromagnetic field which it induces and builds up by the coherent interaction of successive bunches with the chosen longitudinal mode. The CLIC Transfer Structure is original in that it operates at 30 GHz and uses teeth-like corrugations to slow down the hybrid TM mode to make it synchronous with the drive beam. The beam energy is transformed into rf power, which travels along the structure and is collected by the output couplers. The 30 GHz rf power is then transported by means of two waveguides to two main linac disk-loaded accelerating structures. This report describes the CLIC Transfer Structure design, 3-D computer simulations, model construction and measure-ments as well as the prototype construction and testing with the low energy beam in the CLIC Test Facili...

  15. CLIC Brochure

    CERN Multimedia

    De Melis, Cinzia

    2015-01-01

    After the discovery of the Higgs boson and with upgrades to higher energy and luminosity, the LHC is mapping the route of particle physics into the future. The next step in this journey of discovery could be a linear electron-positron collider, which would complement the LHC and allow high precision measurements of the Higgs boson, the top quark and electroweak processes in addition to possible new physics beyond the Standard Model. The Compact Linear Collider is under development by two worldwide collaborations, pushing the limits of particle acceleration and detection. Technological R&D, physics simulations and engineering studies must all come together to make CLIC a reality.

  16. Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-Gradient Accelerating Structures

    CERN Document Server

    Tecker, F; Kelisani, M; Doebert, S; Grudiev, A; Quirante, J; Riddone, G; Syratchev, I; Wuensch, W; Kononenko, O; Solodko, A; Lebet, S

    2013-01-01

    RF breakdown is a key issue for the multi-TeV highluminosity e+e- Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

  17. Material studies in the frame of CLIC Accelerating structures production conducted within the Mechanics program together with Metso Oy

    CERN Document Server

    Nurminen, Janne

    2012-01-01

    MeChanICs (Marie Curie Linking Industry to CERN) is an Industry to Academia Partnership and Pathways (IAPP) platform for precision manufacturing knowledge exchange bringing together five Finnish manufacturing companies with Helsinki Insitute of Physics (HIP) and CERN. The scientific objective of MeChanICs project is to contribute to the manufacturing RTD of CLIC enabling technologies. The focus is on the design, materials, machining, brazing and assembly of A CLIC accelerating structure. This study deals with the materials work package of the program and wants to explore the following items: 1) producing copper accelerating structures for CLIC from raw copper powder by near net shape hot isostatic pressing (HIP). 2) The feasibility to use HIP diffusion bonding of the accelerator structures as a function of surface quality and applied temperature and pressure. 3) Brazing for CLIC AS auxiliary systems, like water cooling or damping manifolds, to the disc stack by coating one of the brazing partners with an enab...

  18. Study of the Thermo-Mechanical Behavior of the CLIC Two-Beam Modules

    CERN Document Server

    Rossi, F; Riddone, G; Österberg, K; Kossyvakis, I; Gudkov, D; Samochkine, A

    2013-01-01

    The final luminosity target of the Compact LInear Collider (CLIC) imposes a micron-level stability requirement on the two-meter repetitive two-beam modules constituting the main linacs. Two-beam prototype modules are being assembled to extensively study their thermo-mechanical behaviour under different operation modes. The power dissipation occurring in the modules will be reproduced and the efficiency of the corresponding cooling systems validated. At the same time, the real environmental conditions present in the CLIC tunnel will be studied. Air conditioning and ventilation systems have been installed in the dedicated laboratory. The air temperature will be changed from 20 to 40°C, while the air flow rate will be varied up to 0.8 m/s. During all experimental tests, the alignment of the RF structures will be monitored to investigate the influence of power dissipation and air temperature on the overall thermo-mechanical behaviour. \

  19. Thermo-Mechanical tests for the CLIC two-beam module study

    CERN Document Server

    Xydou, A; Riddone, G; Daskalaki, E

    2014-01-01

    The luminosity goal of CLIC requires micron level precision with respect to the alignment of the components on its two-meter long modules, composing the two main linacs. The power dissipated inside the module components introduces mechanical deformations affecting their alignment and therefore the resulting machine performance. Several two-beam prototype modules must be assembled to extensively measure their thermo-mechanical behavior under different operation modes. In parallel, the real environmental conditions present in the CLIC tunnel should be studied. The air conditioning and ventilation system providing specified air temperature and flow has been installed in the dedicated laboratory. The power dissipation occurring in the modules is being reproduced by the electrical heaters inserted inside the RF structure mock-ups and the quadrupoles. The efficiency of the cooling systems is being verified and the alignment of module components is monitored. The measurement results will be compared to finite elemen...

  20. Status of a study of stabilization and fine positioning of CLIC quadrupoles to the nanometre level

    CERN Document Server

    Artoos, K; Esposito, M; Fernandez Carmona, P; Guinchard, M; Hauviller, C; Janssens, S; Kuzmin, A; Leuxe, R; Moron Ballester, R

    2011-01-01

    Mechanical stability to the nanometre and below is required for the Compact Linear Collider (CLIC) quadrupoles to frequencies as low as 1 Hz. An active stabilization and positioning system based on very stiff piezo electric actuators and inertial reference masses is under study for the Main Beam Quadrupoles (MBQ). The stiff support was selected for robustness against direct forces and for the option of incrementally repositioning the magnet with nanometre resolution. The technical feasibility was demonstrated by a representative test mass being stabilized and repositioned to the required level in the vertical and lateral direction. Technical issues were identified and the development programme of the support, sensors, and controller was continued to increase the performance, integrate the system in the overall controller, adapt to the accelerator environment, and reduce costs. The improvements are implemented in models, test benches, and design of the first stabilized prototype CLIC magnet. The characterizati...

  1. CLIC Muon Sweeper Design

    CERN Document Server

    Aloev, A; Gatignon, L; Modena, M; Pilicer, B; Tapan, I

    2016-01-01

    There are several background sources which may affect the analysis of data and detector performans at the CLIC project. One of the important background source is halo muons, which are generated along the beam delivery system (BDS), for the detector performance. In order to reduce muon background, magnetized muon sweepers have been used as a shielding material that is already described in a previous study for CLIC [1]. The realistic muon sweeper has been designed with OPERA. The design parameters of muon sweeper have also been used to estimate muon background reduction with BDSIM Monte Carlo simulation code [2, 3].

  2. Thermal joining studies of CLIC accelerating structures and Establishment of a test bench and studies of thermomechanical behaviour of a CLIC two beam module

    CERN Document Server

    Rossi, Fabrizio

    2013-01-01

    The assembly procedure of the CLIC accelerating structures is constituted of several steps, involving ultra-precision machining, heating cycles at very high temperatures and many quality controls necessary to fulfil the very tight technical requirements. Diverse issues are related to the diffusion bonding process of CLIC accelerating structures; due to diffusion creep mechanisms occurring at high temperature and low stress, residual deformations might be present at the end of the joining process. A theoretical and experimental approach is presented here in order to understand this issue further and feedback on the design process. As a second issue tackled here, the final alignment of CLIC is also affected by the power dissipation occurring in the module during the normal operation modes and resulting in time-varying non-uniform thermal fields. The thermo-mechanical models of CLIC two-beam modules developed in the past are then useful to predict the structural deformations affecting the final alignment of the ...

  3. Interaction of Human Chloride Intracellular Channel Protein 1 (CLIC1) with Lipid Bilayers: A Fluorescence Study.

    Science.gov (United States)

    Hare, Joanna E; Goodchild, Sophia C; Breit, Samuel N; Curmi, Paul M G; Brown, Louise J

    2016-07-12

    Chloride intracellular channel protein 1 (CLIC1) is very unusual as it adopts a soluble glutathione S-transferase-like canonical fold but can also autoinsert into lipid bilayers to form an ion channel. The conversion between these forms involves a large, but reversible, structural rearrangement of the CLIC1 module. The only identified environmental triggers controlling the metamorphic transition of CLIC1 are pH and oxidation. Until now, there have been no high-resolution structural data available for the CLIC1 integral membrane state, and consequently, a limited understanding of how CLIC1 unfolds and refolds across the bilayer to form a membrane protein with ion channel activity exists. Here we show that fluorescence spectroscopy can be used to establish the interaction and position of CLIC1 in a lipid bilayer. Our method employs a fluorescence energy transfer (FRET) approach between CLIC1 and a dansyl-labeled lipid analogue to probe the CLIC1-lipid interface. Under oxidizing conditions, a strong FRET signal between the single tryptophan residue of CLIC1 (Trp35) and the dansyl-lipid analogue was detected. When considering the proportion of CLIC1 interacting with the lipid bilayer, as estimated by fluorescence quenching experiments, the FRET distance between Trp35 and the dansyl moiety on the membrane surface was determined to be ∼15 Å. This FRET-detected interaction provides direct structural evidence that CLIC1 associates with membranes. The results presented support the current model of an oxidation-driven interaction of CLIC1 with lipid bilayers and also propose a membrane anchoring role for Trp35. PMID:27299171

  4. A Study of the Beam Physics in the CLIC Drive Beam Decelerator

    CERN Document Server

    Adli, Erik; Stapnes, Steinar

    2009-01-01

    CLIC is a study for a Multi-TeV e+e- linear collider, in which the rf power for the main linacs is extracted from 100 ampere electron drive beams, by the use of specially designed power extraction structures. Up to 90% of the beam energy is extracted from the drive beams along one kilometer long decelerator sectors, rendering the beam transport challenging. We have identified two major challenges for robust beam transport: the significant transverse wakes in the power extraction structures, and the large energy spread induced by the power extraction process. By beam dynamics studies we have qualified power extraction structure designs, leading to the present CLIC baseline structure in which the transverse wakes are sufficiently mitigated. We have further shown that the beam energy spread induced by the deceleration implies that standard 1-to-1 correction might not ensure satisfactory drive beam transport. As alternative, we propose a decelerator orbit correction scheme based on dispersion-free steering and ex...

  5. CLIC expands to include the Southern Hemisphere

    CERN Multimedia

    Roberto Cantoni

    2010-01-01

    Australia has recently joined the CLIC collaboration: the enlargement will bring new expertise and resources to the project, and is especially welcome in the wake of CERN budget redistributions following the recent adoption of the Medium Term Plan.   The countries involved in CLIC collaboration With the signing of a Memorandum of Understanding on 26 August 2010, the ACAS network (Australian Collaboration for Accelerator Science) became the 40th member of in the multilateral CLIC collaboration making Australia the 22nd country to join the collaboration. “The new MoU was signed by the ACAS network, which includes the Australian Synchrotron and the University of Melbourne”, explains Jean-Pierre Delahaye, CLIC Study Leader. “Thanks to their expertise, the Australian institutes will contribute greatly to the CLIC damping rings and the two-beam test modules." Institutes from any country wishing to join the CLIC collaboration are invited to assume responsibility o...

  6. Technological challenges of CLIC

    CERN Document Server

    CERN. Geneva; Döbert, Steffen; Arnau-Izquierdo, G; Redaelli, Stefano; Mainaud, Helène; Lefèvre, Thibaut

    2006-01-01

    Future e+e- Linear Colliders offer the potential to explore new physics at the TeV scale and beyond to very high precision. While the International Linear Collider (ILC) scheme of a collider in the 0.5 - 1 TeV range enters the engineering design phase, the Compact Linear Collider (CLIC) study explores the technical feasibility of a collider capable of reaching into the multi-TeV energy domain. Key ingredients of the CLIC scheme are acceleration at high-frequency (30 GHz) and high-gradient (150 MV/m) in normal conducting structures and the use of the so-called Two Beam Acceleration concept, where a high-charge electron beam (drive beam) running parallel to the main beam is decelerated to provide the RF power to accelerate the main beam itself. A vigorous R&D effort is presently developed by the CLIC international collaboration to demonstrate its feasibility by 2010, when the first physics results from LHC should be available to guide the choice of the centre-of-mass energy better suited to explore the futu...

  7. Planned Contributions of The Wcrp Climate and Cryosphere (clic) Project To Mountain Hydrological Studies

    Science.gov (United States)

    Barry, R. G.

    Formal discussions within the World Climate Research Programme (WCRP) since 1997 have addressed the question of the role of the cryosphere in the climate system. An outcome has been the approval in March 2000 of a Science and Co-ordination Plan for a new Climate and Cryosphere (CliC) project by the WCRP Joint Scientific Com- mittee in March 2000. The concept of this plan (WCRP, 2001) and particular topics of concern for high-mountain hydrology are discussed here. The proposed definition of the cryosphere is that portion of the climate system consisting of the world's ice masses and snow deposits. of relevance for mountains are: ice caps and glaciers, sea- sonal snow cover, lake and river ice, and seasonally frozen ground and permafrost. Existing projects both within the framework of the WCRP, as well as of the IGBP are mainly regional and links into the global climate research effort are not sufficiently comprehensive. The WCRP GEWEX project has cryospheric components concerning the high latitude hydrological cycle, but mountain studies are currently only in Ti- bet. Other relevant programs include: the IGBP-BAHC Mountain Research Initiative, Global Land Ice Measurements from Space (GLIMS), and Permafrost and Climate in Europe (PACE), for example. Integration of existing cryospheric projects within a global research structure, together with new efforts addressing current gaps, is re- quired in order to: - enhance links between regional and global climatic components studies, - promote appropriate treatment of cryospheric processes in climate models, and - assemble and make accessible quality controlled, well documented, comprehen- sive and coherent global gridded data sets necessary for driving and validating climate models. The principal scientific questions relating to the cryosphere in mountain re- gions concern: - glacier melt contributions to global sea level change, - the energy and water cycle in regions with land ice, snow cover and frozen ground, - the

  8. CLICdp Overview. Overview of physics potential at CLIC

    Directory of Open Access Journals (Sweden)

    Levy Aharon

    2015-01-01

    Full Text Available CLICdp, the CLIC detector and physics study, is an international collaboration presently composed of 23 institutions. The collaboration is addressing detector and physics issues for the future Compact Linear Collider (CLIC, a high-energy electron-positron accelerator which is one of the options for the next collider to be built at CERN. Precision physics under challenging beam and background conditions is the key theme for the CLIC detector studies. This leads to a number of cutting-edge R&D activities within CLICdp. The talk includes a brief introduction to CLIC, accelerator and detectors, hardware R&D as well as physics studies at CLIC.

  9. Overview of the CLIC beam instrumentation

    CERN Document Server

    Lefèvre, T

    2011-01-01

    The performances of the Compact Linear Collider (CLIC) would rely on extremely tight tolerances on most beam parameters. The requirements for the CLIC beam instrumentation have been reviewed and studied in detail for the whole accelerator complex. In the context of the completion of the CLIC Conceptual Design Report, a first attempt was made to propose a technical solution for every CLIC instruments. Even if these choices were based on most recent technological achievements, whenever possible, alternatives solutions focusing on potential improvements on performance, reliability or cost minimization are proposed and will be studied in the future. This paper presents an overview of the CLIC beam instruments, gives a status of their already achieved performances and presents the future work activities.

  10. Experimental study of DC vacuum breakdown and application to high-gradient accelerating structures for CLIC

    CERN Document Server

    Shipman, Nicholas; Jones, Roger

    2016-01-01

    The compact linear collider (CLIC) is a leading candidate for the next generation high energy linear collider. As any breakdown would result in a partial or full loss of luminosity for the pulse in which it occurs, obtaining a low breakdown rate in CLIC accelerating structures is a critical requirement for the successful operation of the proposed collider. This thesis presents investigations into the breakdown phenomenon primarily in the low breakdown rate regime of interest to CLIC, performed using the CERN DC spark systems between 2011 and 2014. The design, construction and commissioning of several new pieces of hardware, as well as the development of improved techniques to measuring the inter-electrode gap distance are detailed. These hardware improvements were fundamental in enabling the exciting new experiments mentioned below, which in turn have provided significant additional insight into the phenomenon of breakdown. Experiments were performed to measure fundamental parameters of individual breakdowns...

  11. Beam Position Monitoring at CLIC

    CERN Document Server

    Prochnow, J

    2003-01-01

    At the European Organisation for Nuclear Research CERN in Geneva, Switzerland the design of the Compact LInear Collider (CLIC) for high energy physics is studied. To achieve the envisaged high luminosity the quadrupole magnets and radio-frequency accelerating structures have to be actively aligned with micron precision and submicron resolution. This will be done using beam-based algorithms which rely on beam position information inside of quadrupoles and accelerating structures. After a general introduction to the CLIC study and the alignment algorithms, the concept of the interaction between beams and radio-frequency structures is given. In the next chapter beam measurements and simulations are described which were done to study the performance of cavity beam position monitors (BPM). A BPM design is presented which is compatible with the multi-bunch operation at CLIC and could be used to align the quadrupoles. The beam position inside the accelerating structures will be measured by using the structures thems...

  12. Studies of Cs3Sb cathodes for the CLIC drive beam photo injector option

    CERN Document Server

    Martini, Irene; Doebert, Steffen; Fedosseev, Valentine; Hessler, Christoph; Martyanov, Mikhail

    2013-01-01

    Within the CLIC (Compact Linear Collider) project, feasibility studies of a photo injector option for the drive beam as an alternative to its baseline design using a thermionic electron gun are on-going. This R&D program covers both the laser and the photocathode side. Whereas the available laser pulse energy in ultra-violet (UV) is currently limited by the optical defects in the 4thharmonics frequency conversion crystal induced by the0.14 ms long pulse trains, recent measurements of Cs3Sbphotocathodes sensitive to green light showed their potential to overcome this limitation. Moreover, using visible laser beams leads to better stability of produced electron bunches and one can take advantages of the availability of higher quality optics. The studied Cs3Sbphotocathodes have been produced in the CERN photo emission laboratory using the co-deposition technique and tested in a DC gun set-up. The analysis of data acquired during the cathode production process will be presented in this paper, as well as the r...

  13. Mechanical integration studies for the CLIC vertex and inner tracking detectors

    CERN Document Server

    Villarejo Bermudez, M.A.; Gerwig, H.

    2015-01-01

    Since the publication of the CLIC Conceptual Design Report, work has proceeded in order to establish a preliminary mechanical design for the innermost CLIC detector region. This note proposes a design for the main Carbon-Fibre Reinforced Polymer (CFRP) structural elements of the inner detectors, for the beam pipe and their supports. It also describes an assembly sequence for the integration of the sensors and the mechanical components. Mechanical simulations of different structural elements and a material budget estimation are appended. Details of a proposed cabling layout for all the subdetectors are included.

  14. CLIC MDI Overview

    OpenAIRE

    Gatignon, Lau

    2012-01-01

    This paper gives an introduction to the layout of the CLIC Machine Detector Interface as it has been defined for the CLIC Conceptual Design Report. We concentrate on the specific case of the CLIC_SiD detector, although the push-pull concept for two detectors has been included in the design. Some recent work and developments are described as well. However, for the details we refer to the detailed technical talks at this conference.

  15. Study of a 5-Tesla large aperture coil for the CLIC detector

    CERN Document Server

    Cure, B

    2011-01-01

    The present design of a CLIC detector foresees a large solenoid magnet with a 6 m aperture and a magnetic induction of 5 T at the interaction point. This can be achieved by a thin superconducting coil. This report gives the typical main parameters of such a coil and presents the feasibility based on and compared with the CMS and Atlas solenoid coil designs, indicating the limits on the conductor and the identified R&D prospects.

  16. CLIC Physics Overview

    CERN Document Server

    AUTHOR|(SzGeCERN)471575

    2016-01-01

    This paper, based on the invited talk given at the 17th Lomonosov Conference of Elementary Particle Physics, summarizes the physics program at CLIC, with particular emphasis on the Higgs physics studies. The physics reach of CLIC operating in three energy stages, at 350 GeV, 1.4 TeV and 3 TeV center-of-mass energies is reviewed. The energy-staged approach is motivated by the high-precision physics measurements in the Higgs and top sector as well as by direct and indirect searches for beyond the Standard Model physics. The first stage, at or above 350 GeV, gives access to precision Higgs physics through the Higgsstrahlung and WW-fusion production processes, providing absolute values of the Higgs couplings to fermions and bosons. This stage also addresses precision top physics around the top-pair-production threshold. The second stage, at 1.4 TeV, opens the energy frontier, allowing for the discovery of new physics phenomena. This stage also gives access to additional Higgs properties, such as the top-Yukawa co...

  17. Successful start for new CLIC test facility

    CERN Multimedia

    2004-01-01

    A new test facility is being built to study key feasibility issues for a possible future linear collider called CLIC. Commissioning of the first part of the facility began in June 2003 and nominal beam parameters have been achieved already.

  18. CLIC CTF3 for open days

    CERN Multimedia

    CLIC

    2013-01-01

    CLIC – the Compact Linear Collider – is a study for a future accelerator that reaches unprecedented energies for electrons and their antimatter twins, positrons. It uses a novel two-beam acceleration scheme in which the electrons and positrons are propelled to high energy by an additional high current electron beam, the so-called Drive Beam. In order to generate this high current Drive Beam, a long train of electron bunches is accelerated, parts of the train delayed in a Delay Loop and Combiner Rings, and interleaved by transversely deflecting radio-frequency cavities. The CLIC Test Facility CTF3, which is shown in the movie, examines the new technologies envisioned by the CLIC design, in particular the Drive Beam generation and the two-beam acceleration. It is a scaled-down version of the CLIC facility, and it has demonstrated the feasibility of the novel scheme.

  19. CLIC CTF3 for open days

    CERN Multimedia

    2013-01-01

    (subt french) CLIC – the Compact Linear Collider – is a study for a future accelerator that reaches unprecedented energies for electrons and their antimatter twins, positrons. It uses a novel two-beam acceleration scheme in which the electrons and positrons are propelled to high energy by an additional high current electron beam, the so-called Drive Beam. In order to generate this high current Drive Beam, a long train of electron bunches is accelerated, parts of the train delayed in a Delay Loop and Combiner Rings, and interleaved by transversely deflecting radio-frequency cavities. The CLIC Test Facility CTF3, which is shown in the movie, examines the new technologies envisioned by the CLIC design, in particular the Drive Beam generation and the two-beam acceleration. It is a scaled-down version of the CLIC facility, and it has demonstrated the feasibility of the novel scheme.

  20. Acquisition system for the CLIC Module

    CERN Document Server

    Vilalte, Sebastien

    2011-01-01

    The status of R&D activities for CLIC module acquisition are discussed [1]. LAPP is involved in the design of the local CLIC module acquisition crate, described in the document Study of the CLIC Module Front-End Acquisition and Evaluation Electronics [2]. This acquisition system is a project based on a local crate, assigned to the CLIC module, including several mother boards. These motherboards are foreseen to hold mezzanines dedicated to the different subsystems. This system has to work in radiation environment. LAPP is involved in the development of Drive Beam stripline position monitors read-out, described in the document Drive Beam Stripline BPM Electronics and Acquisition [3]. LAPP also develops a generic acquisition mezzanine that allows to perform all-around acquisition and components tests for drive beam stripline BPM read-out.

  1. Detector Optimization of the CLIC Tracker

    CERN Document Server

    Saxe, Gandalf

    2015-01-01

    CLIC (Compact Linear Collider) is a proposed high-energy electron-positron collider at CERN [1] that, if approved, will be built at the feet of the Jura Mountains in Switzerland, passing through CERN. As opposed to hadrons, electrons (e-) and positrons (e+) are elementary particles. Therefore, e-e+ collisions give a well defined initial state which allows high precision studies. A circular collider is not a viable option when going to high energies (several TeV) for a e-e+ collider due to synchrotron radiation. Therefore CLIC is designed as a linear collider. CLIC is proposed to be build in three center-of-mass energy stages: 380 GeV, 1.4 TeV and 3.0 TeV. The CLIC physics program includes the high precision measurements of the Higgs and top properties, the observation of rare processes, and the possible discovery of new particles [3].

  2. Fluka and thermo-mechanical studies for the CLIC main dump

    CERN Document Server

    Mereghetti, Alessio; Vlachoudis, Vasilis

    2011-01-01

    In order to best cope with the challenge of absorbing the multi-MW beam, a water beam dump at the end of the CLIC post-collision line has been proposed. The design of the dump for the Conceptual Design Report (CDR) was checked against with a set of FLUKA Monte Carlo simulations, for the estimation of the peak and total power absorbed by the water and the vessel. Fluence spectra of escaping particles and activation rates of radio-nuclides were computed as well. Finally, the thermal transient behavior of the water bath and a thermo-mechanical analysis of the preliminary design of the window were done.

  3. CLIC Status and Outlook

    CERN Document Server

    Stapnes, Stapnes

    2012-01-01

    The Compact Linear Collider study (CLIC) is in the process of completing a Conceptual Design Report (CDR) for a multi-TeV linear electron-positron collider. The CLICconcept is based on high gradient normal-conducting accelerating structures. The RF power for the acceleration of the colliding beams is produced by a novel two beam acceleration scheme, where power is extracted from a high current drive beam that runs parallel with the main linac. In order to establish the feasibility of this concept a number of key issues have been addressed. A short summary of the progress and status of the corresponding studies will be given, as well as an outline of the preparation and work towards an implementation plan by 2016.

  4. Studies on high-precision machining and assembly of CLIC RF structures

    CERN Document Server

    Huopana, J; Riddone, G; Österberg, K

    2010-01-01

    The Compact Linear Collider (CLIC) is currently under development at CERN as a potential multi-TeV e+e– collider. The manufacturing and assembly tolerances for the required RF components are essential for the final efficiency and for the operation of CLIC. The proper function of an accelerating structure is sensitive to mechanical errors in the shape and the alignment of the accelerating cavity. The current tolerances are in the micron range. This raises challenges in the field of mechanical design and demands special manufacturing technologies and processes. Currently the mechanical design of the accelerating structures is based on a disk design. Alternatively, it is possible to create the accelerating assembly from quadrants, which has the potential to be favoured for the mass production due to simplicity and cost. In this case, the functional shape inside of the accelerating structure remains the same and a single assembly uses less parts. This paper focuses on the development work done in design and sim...

  5. The CLIC Physics Potential

    CERN Document Server

    Robson, Aidan

    2016-01-01

    The physics and detector studies for the Compact Linear Collider (CLIC) are introduced. A staged programme of $e^{+}e^{−}$ collisions covering $\\sqrt{s}$ = 380 GeV, 1.5 TeV, and 3 TeV would allow precise measurements of Higgs boson couplings, in many cases to the percent level. This corresponds to precision higher than that expected for the high-luminosity Large Hadron Collider. Such precise Higgs coupling measurements would allow sensitivity to a variety of new physics models and the ability to distinguish between them. In addition, new particles directly produced in pairs could be measured with great precision, and measurements in the top-quark sector would provide sensitivity to new physics effects at the scales of tens of TeV.

  6. CLIC1 regulates dendritic cell antigen processing and presentation by modulating phagosome acidification and proteolysis

    Science.gov (United States)

    Salao, Kanin; Jiang, Lele; Li, Hui; Tsai, Vicky W.-W.; Husaini, Yasmin; Curmi, Paul M. G.; Brown, Louise J.; Brown, David A.

    2016-01-01

    ABSTRACT Intracellular chloride channel protein 1 (CLIC1) participates in inflammatory processes by regulating macrophage phagosomal functions such as pH and proteolysis. Here, we sought to determine if CLIC1 can regulate adaptive immunity by actions on dendritic cells (DCs), the key professional antigen presenting cells. To do this, we first generated bone marrow-derived DCs (BMDCs) from germline CLIC1 gene-deleted (CLIC1−/−) and wild-type (CLIC1+/+) mice, then studied them in vitro and in vivo. We found phagocytosis triggered cytoplasmic CLIC1 translocation to the phagosomal membrane where it regulated phagosomal pH and proteolysis. Phagosomes from CLIC1−/− BMDCs displayed impaired acidification and proteolysis, which could be reproduced if CLIC1+/+, but not CLIC1−/− cells, were treated with IAA94, a CLIC family ion channel blocker. CLIC1−/− BMDC displayed reduced in vitro antigen processing and presentation of full-length myelin oligodendrocyte glycoprotein (MOG) and reduced MOG-induced experimental autoimmune encephalomyelitis. These data suggest that CLIC1 regulates DC phagosomal pH to ensure optimal processing of antigen for presentation to antigen-specific T-cells. Further, they indicate that CLIC1 is a novel therapeutic target to help reduce the adaptive immune response in autoimmune diseases. PMID:27113959

  7. Beam position monitoring at CLIC

    OpenAIRE

    Prochnow, Jan Erik

    2003-01-01

    At the European Organisation for Nuclear Research CERN in Geneva, Switzerland the design of the Compact LInear Collider (CLIC) for high energy physics is studied. To achieve the envisaged high luminosity the quadrupole magnets and radio-frequency accelerating structures have to be actively aligned with micron precision and submicron resolution. This will be done using beam-based algorithms which rely on beam position information inside of quadrupoles and accelerating structures. After a gener...

  8. CLIC brochure (English version)

    CERN Multimedia

    Lefevre, Christiane

    2012-01-01

    The world's biggest and most powerful accelerator, the LHC, is mapping the route of particle physics for the future. The next step, to complement the LHC in exploring this new region, is most likely to be a linear electron-positron collider. The Compact Linear Collider (CLIC) is a novel approach to such a collider. It is currently under development by the CLIC collaboration, which is hosted at CERN.

  9. Simulation Study of Cool-Down of the CLIC Wiggler Magnets

    CERN Document Server

    Liu, L; van Weelderen, R; Xiong, L

    2013-01-01

    The cryogenic system for the CLIC wiggler magnets is under design. The cooldown process is one of the main dimensioning factors for the system. In this paper, the heat transfer model used to simulate the cool-down process is presented. Different configurations are then investigated and a detailed analysis of the corresponding temperature evolutions along the magnet strings is calculated. The temperature profiles are evaluated for the flowing helium as well as for the magnets allowing a detailed analysis of the temperature gradients. The impact of some key parameters, like the mass-flow rate, the diameter of the cooling channels and of the thermal coupling between the helium and the magnets is also investigated.

  10. Initial study on the shape optimisation of the CLIC crab cavity

    CERN Document Server

    Ambattu, P K; Carter, R G; Dexter, A C; Jones, R M; McIntosh, P

    2008-01-01

    The compact linear collider (CLIC) requires a crab cavity to align bunches prior to collision. The bunch structure demands tight amplitude and phase tolerances of the RF fields inside the cavity, for the minimal luminosity loss. Beam loading effects require special attention as it is one potential sources of field errors in the cavity. In order to assist the amplitude and phase control, we propose a travelling wave (TW) structure with a high group velocity allowing rapid propagation of errors out of the system. Such a design makes the cavity structure significantly different from previous ones. This paper will look at the implications of this on other cavity parameters and the optimisation of the cavity geometry.

  11. Light-flavor squark reconstruction at CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)548062; Weuste, Lars

    2015-01-01

    We present a simulation study of the prospects for the mass measurement of TeV-scale light- flavored right-handed squark at a 3 TeV e+e collider based on CLIC technology. The analysis is based on full GEANT4 simulations of the CLIC_ILD detector concept, including Standard Model physics backgrounds and beam-induced hadronic backgrounds from two- photon processes. The analysis serves as a generic benchmark for the reconstruction of highly energetic jets in events with substantial missing energy. Several jet finding algorithms were evaluated, with the longitudinally invariant kt algorithm showing a high degree of robustness towards beam-induced background while preserving the features typically found in algorithms developed for e+e- collisions. The presented study of the reconstruction of light-flavored squarks shows that for TeV-scale squark masses, sub-percent accuracy on the mass measurement can be achieved at CLIC.

  12. CLIC Test Facility 3

    CERN Multimedia

    Kossyvakis, I; Faus-golfe, A

    2007-01-01

    The design of CLIC is based on a two-beam scheme, where short pulses of high power 30 GHz RF are extracted from a drive beam running parallel to the main beam. The 3rd generation CLIC Test Facility (CTF3) will demonstrate the generation of the drive beam with the appropriate time structure, the extraction of 30 GHz RF power from this beam, as well as acceleration of a probe beam with 30 GHz RF cavities. The project makes maximum use of existing equipment and infrastructure of the LPI complex, which became available after the closure of LEP.

  13. Physics highlights at ILC and CLIC

    CERN Document Server

    Lukić, Strahinja

    2015-01-01

    In this lecture, the physics potential for the e+e- linear collider experiments ILC and CLIC is reviewed. The experimental conditions are compared to those at hadron colliders and their intrinsic value for precision experiments, complementary to the hadron colliders, is discussed. The detector concepts for ILC and CLIC are outlined in their most important aspects related to the precision physics. Highlights from the physics program and from the benchmark studies are given. It is shown that linear colliders are a promising tool, complementing the LHC in essential ways to test the Standard Model and to search for new physics.

  14. The CLIC Vertex Detector

    CERN Document Server

    Dannheim, D

    2015-01-01

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a meas- urement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → W b will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit tim- ing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC ver- tex det...

  15. The CLIC Vertex Detector

    Science.gov (United States)

    Dannheim, D.

    2015-03-01

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a measurement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → Wb will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit timing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC vertex detector. It comprises fast, low-power and small-pitch readout ASICs implemented in 65 nm CMOS technology (CLICpix) coupled to ultra-thin planar or active HV-CMOS sensors via low-mass interconnects. The power dissipation of the readout chips is reduced by means of power pulsing, allowing for a cooling system based on forced gas flow. This contribution reviews the requirements and design optimisation for the CLIC vertex detector and gives an overview of recent R&D achievements in the domains of sensors, readout and detector integration.

  16. The CLIC Vertex Detector

    International Nuclear Information System (INIS)

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a measurement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → Wb will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit timing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC vertex detector. It comprises fast, low-power and small-pitch readout ASICs implemented in 65 nm CMOS technology (CLICpix) coupled to ultra-thin planar or active HV-CMOS sensors via low-mass interconnects. The power dissipation of the readout chips is reduced by means of power pulsing, allowing for a cooling system based on forced gas flow. This contribution reviews the requirements and design optimisation for the CLIC vertex detector and gives an overview of recent R and D achievements in the domains of sensors, readout and detector integration

  17. Performance of particle flow calorimetry at CLIC

    International Nuclear Information System (INIS)

    The particle flow approach to calorimetry can provide unprecedented jet energy resolution at a future high energy collider, such as the International Linear Collider (ILC). However, the use of particle flow calorimetry at the proposed multi-TeV Compact Linear Collider (CLIC) poses a number of significant new challenges. At higher jet energies, detector occupancies increase, and it becomes increasingly difficult to resolve energy deposits from individual particles. The experimental conditions at CLIC are also significantly more challenging than those at previous electron–positron colliders, with increased levels of beam-induced backgrounds combined with a bunch spacing of only 0.5 ns. This paper describes the modifications made to the PandoraPFA particle flow algorithm to improve the jet energy reconstruction for jet energies above 250 GeV. It then introduces a combination of timing and pT cuts that can be applied to reconstructed particles in order to significantly reduce the background. A systematic study is performed to understand the dependence of the jet energy resolution on the jet energy and angle, and the physics performance is assessed via a study of the energy and mass resolution of W and Z particles in the presence of background at CLIC. Finally, the missing transverse momentum resolution is presented, and the fake missing momentum is quantified. The results presented in this paper demonstrate that high granularity particle flow calorimetry leads to a robust and high resolution reconstruction of jet energies and di-jet masses at CLIC.

  18. CERN: Making CLIC tick

    International Nuclear Information System (INIS)

    While the Large Hadron Collider (LHC) scheme for counter-rotating proton beams in a new superconducting ring to be built in CERN's existing 27-kilometre LEP tunnel is being pushed as the Laboratory's main construction project for the 1990s, research and development continues in parallel for an eventual complementary attack on new physics frontiers with CERN's Linear Collider - CLIC - firing TeV electron and positron beams at each other

  19. Luminosity Upgrade of CLIC LHC ep/gp Collider

    CERN Document Server

    Aksakal, H; Nergiz, Z; Schulte, D; Zimmermann, F

    2007-01-01

    An energy frontier or QCD Explorer ep and collider can be realized by colliding high-energy photons generated by Compton backscattered off a CLIC electron beam, at either 75 GeV or 1.5 TeV, with protons or ions stored in the LHC. In this study we discuss a performance optimization of this type of collider by tailoring the parameters of both CLIC and LHC. An estimate of the ultimately achievable luminosity is given.

  20. CLIC CDR - physics and detectors: CLIC conceptual design report

    International Nuclear Information System (INIS)

    This report forms part of the Conceptual Design Report (CDR) of the Compact LInear Collider (CLIC). The CLIC accelerator complex is described in a separate CDR volume. A third document, to appear later, will assess strategic scenarios for building and operating CLIC in successive center-of-mass energy stages. It is anticipated that CLIC will commence with operation at a few hundred GeV, giving access to precision standard-model physics like Higgs and top-quark physics. Then, depending on the physics landscape, CLIC operation would be staged in a few steps ultimately reaching the maximum 3 TeV center-of-mass energy. Such a scenario would maximize the physics potential of CLIC providing new physics discovery potential over a wide range of energies and the ability to make precision measurements of possible new states previously discovered at the Large Hadron Collider (LHC). The main purpose of this document is to address the physics potential of a future multi-TeV e+e- collider based on CLIC technology and to describe the essential features of a detector that are required to deliver the full physics potential of this machine. The experimental conditions at CLIC are significantly more challenging than those at previous electron-positron colliders due to the much higher levels of beam-induced backgrounds and the 0.5 ns bunch-spacing. Consequently, a large part of this report is devoted to understanding the impact of the machine environment on the detector with the aim of demonstrating, with the example of realistic detector concepts, that high precision physics measurements can be made at CLIC. Since the impact of background increases with energy, this document concentrates on the detector requirements and physics measurements at the highest CLIC center-of-mass energy of 3 TeV. One essential output of this report is the clear demonstration that a wide range of high precision physics measurements can be made at CLIC with detectors which are challenging, but considered

  1. CLIC CDR - physics and detectors: CLIC conceptual design report.

    Energy Technology Data Exchange (ETDEWEB)

    Berger, E.; Demarteau, M.; Repond, J.; Xia, L.; Weerts, H. (High Energy Physics); (Many)

    2012-02-10

    This report forms part of the Conceptual Design Report (CDR) of the Compact LInear Collider (CLIC). The CLIC accelerator complex is described in a separate CDR volume. A third document, to appear later, will assess strategic scenarios for building and operating CLIC in successive center-of-mass energy stages. It is anticipated that CLIC will commence with operation at a few hundred GeV, giving access to precision standard-model physics like Higgs and top-quark physics. Then, depending on the physics landscape, CLIC operation would be staged in a few steps ultimately reaching the maximum 3 TeV center-of-mass energy. Such a scenario would maximize the physics potential of CLIC providing new physics discovery potential over a wide range of energies and the ability to make precision measurements of possible new states previously discovered at the Large Hadron Collider (LHC). The main purpose of this document is to address the physics potential of a future multi-TeV e{sup +}e{sup -} collider based on CLIC technology and to describe the essential features of a detector that are required to deliver the full physics potential of this machine. The experimental conditions at CLIC are significantly more challenging than those at previous electron-positron colliders due to the much higher levels of beam-induced backgrounds and the 0.5 ns bunch-spacing. Consequently, a large part of this report is devoted to understanding the impact of the machine environment on the detector with the aim of demonstrating, with the example of realistic detector concepts, that high precision physics measurements can be made at CLIC. Since the impact of background increases with energy, this document concentrates on the detector requirements and physics measurements at the highest CLIC center-of-mass energy of 3 TeV. One essential output of this report is the clear demonstration that a wide range of high precision physics measurements can be made at CLIC with detectors which are challenging, but

  2. A Multi-TeV Linear Collider Based on CLIC Technology CLIC Conceptual Design Report

    CERN Document Server

    Burrows, P; Draper, M; Garvey, T; Lebrun, P; Peach, K; Phinney, N; Schmickler, H; Schulte, D; Toge, N

    2012-01-01

    This report describes the accelerator studies for a future multi-TeV e+e- collider based on the Compact Linear Collider (CLIC) technology. The CLIC concept as described in the report is based on high gradient normal-conducting accelerating structures where the RF power for the acceleration of the colliding beams is extracted from a high-current Drive Beam that runs parallel with the main linac. The focus of CLIC R&D over the last years has been on addressing a set of key feasibility issues that are essential for proving the fundamental validity of the CLIC concept. The status of these feasibility studies are described and summarized. The report also includes a technical description of the accelerator components and R&D to develop the most important parts and methods, as well as a description of the civil engineering and technical services associated with the installation. Several larger system tests have been performed to validate the two-beam scheme, and of particular importance are the results from ...

  3. CLIC5A, a component of the ezrin-podocalyxin complex in glomeruli, is a determinant of podocyte integrity.

    Science.gov (United States)

    Wegner, Binytha; Al-Momany, Abass; Kulak, Stephen C; Kozlowski, Kathy; Obeidat, Marya; Jahroudi, Nadia; Paes, John; Berryman, Mark; Ballermann, Barbara J

    2010-06-01

    The chloride intracellular channel 5A (CLIC5A) protein, one of two isoforms produced by the CLIC5 gene, was isolated originally as part of a cytoskeletal protein complex containing ezrin from placental microvilli. Whether CLIC5A functions as a bona fide ion channel is controversial. We reported previously that a CLIC5 transcript is enriched approximately 800-fold in human renal glomeruli relative to most other tissues. Therefore, this study sought to explore CLIC5 expression and function in glomeruli. RT-PCR and Western blots show that CLIC5A is the predominant CLIC5 isoform expressed in glomeruli. Confocal immunofluorescence and immunogold electron microscopy reveal high levels of CLIC5A protein in glomerular endothelial cells and podocytes. In podocytes, CLIC5A localizes to the apical plasma membrane of foot processes, similar to the known distribution of podocalyxin and ezrin. Ezrin and podocalyxin colocalize with CLIC5A in glomeruli, and podocalyxin coimmunoprecipitates with CLIC5A from glomerular lysates. In glomeruli of jitterbug (jbg/jbg) mice, which lack the CLIC5A protein, ezrin and phospho-ERM levels in podocytes are markedly lower than in wild-type mice. Transmission electron microscopy reveals patchy broadening and effacement of podocyte foot processes as well as vacuolization of glomerular endothelial cells. These ultrastructural changes are associated with microalbuminuria at baseline and increased susceptibility to adriamycin-induced glomerular injury compared with wild-type mice. Together, the data suggest that CLIC5A is required for the development and/or maintenance of the proper glomerular endothelial cell and podocyte architecture. We postulate that the interaction between podocalyxin and subjacent filamentous actin, which requires ezrin, is compromised in podocytes of CLIC5A-deficient mice, leading to dysfunction under unfavorable genetic or environmental conditions. PMID:20335315

  4. PACMAN STUDY OF FSI AND MICRO-TRIANGULATION FOR THE PRE-ALIGNMENT OF CLIC

    CERN Document Server

    Kamugasa, William Solomon

    2015-01-01

    The alignment precision of linear colliders is extremely demanding owing to the very narrow beam size at the interaction point. Unlike circular colliders, particles in linear colliders have only one chance to collide and are hence tightly focused to maximise the number of interactions per collision. The PACMAN* project is dedicated to study the integration of both fiducialization and alignment of the components on a common support. FSI (Frequency Scanning Interferometry) and Micro-triangulation will contribute to this goal. FSI realized by Etalon AG’s Absolute Multiline system and Micro-triangulation implemented by QDaedalus system developed at ETH Zurich offer precision of 0.5 μm/m and 2.4 μm/m respectively. However, these systems need to be improved in order to provide the necessary geometric information via distance measurements (multilateration) and angle measurements (triangulation), respectively. The paper describes the current status and the future developments of Absolute Multiline and QDaedalus, ...

  5. Light-flavor squark reconstruction at CLIC

    Science.gov (United States)

    Simon, Frank; Weuste, Lars

    2015-08-01

    We present a simulation study of the prospects for the mass measurement of TeV-scale light-flavored right-handed squarks at a 3 TeV collider based on CLIC technology. In the considered model, these particles decay into their standard-model counterparts and the lightest neutralino, resulting in a signature of two jets plus missing energy. The analysis is based on full GEANT4 simulations of the CLIC_ILD detector concept, including Standard Model physics backgrounds and beam-induced hadronic backgrounds from two-photon processes. The analysis serves as a generic benchmark for the reconstruction of highly energetic jets in events with substantial missing energy. Several jet finding algorithms were evaluated, with the longitudinally invariant algorithm showing a high degree of robustness towards beam-induced background while preserving the features typically found in algorithms developed for collisions. The presented study of the reconstruction of light-flavored squarks shows that for TeV-scale squark masses, sub-percent accuracy on the mass measurement can be achieved at CLIC.

  6. CLIC accelerator modules under construction at CERN

    CERN Multimedia

    Anna Pantelia

    2012-01-01

    The Compact LInear Collider (CLIC) study is dedicated to the design of an electron-positron (e- e+) linear accelerator, colliding particle beams at the energy of 3 TeV. The CLIC required luminosity can be reached with powerful particle beams (14 MW each) colliding with extremely small dimensions and high beam stability at the interaction point. The accelerated particle beams must have dimensions of 45 nm in the horizontal plane and 1 nm in the vertical plane. CLIC relies upon a novel two-beam acceleration concept in which the Radio Frequency (RF) power is extracted from a low energy but high-intensity particle beam, called Drive Beam (DB), and transferred to a parallel high energy accelerating particle beam, called Main Beam (MB). The extraction and transfer of the RF power is achieved by the Power Extraction and Transfer Structures (PETS) and the particle beam acceleration is achieved with high precision RF-Accelerating Structures (AS), operating at 11.9942 GHz with an accelerating gradient of 100 MV/m, whi...

  7. Academic Training - Technological challenges of CLIC

    CERN Multimedia

    Françoise Benz

    2006-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 12, 13, 14, 15 and 16 June 11:00-12:00 - Auditorium, bldg 500 Technological challenges of CLIC R. Corsini, S. Doebert, S. Redaelli, T.Lefevre, CERN-AB and G. Arnau Izquierdo, H. Mainaud, CERN-TS Future e+e- Linear Colliders offer the potential to explore new physics at the TeV scale and beyond to very high precision. While the International Linear Collider (ILC) scheme of a collider in the 0.5 - 1 TeV range enters the engineering design phase, the Compact Linear Collider (CLIC) study explores the technical feasibility of a collider capable of reaching into the multi-TeV energy domain. Key ingredients of the CLIC scheme are acceleration at high-frequency (30 GHz) and high-gradient (150 MV/m) in normal conducting structures and the use of the so-called Two Beam Acceleration concept, where a high-charge electron beam (drive beam) running parallel to the main beam is decelerated to provide the RF power to accelerate the main beam itself. A vigorous R&...

  8. Scalar leptoquark production at TESLA and CLIC based eγ colliders

    International Nuclear Information System (INIS)

    We study scalar leptoquark production at TESLA and CLIC based eγ colliders. Both direct and resolved contributions to the cross section are examined. We find that the masses of scalar leptoquarks can be probed up to about 0.9 TeV at TESLA and 2.6 TeV at CLIC. (orig.)

  9. Scalar leptoquark production at TESLA and CLIC based e-gamma colliders

    OpenAIRE

    Cakir, O.; Ateser, E.; Koru, H.

    2002-01-01

    We study scalar leptoquark production at TESLA and CLIC based e-gamma colliders. Both direct and resolved contributions to the cross section are examined. We find that the masses of scalar leptoquarks can be probed up to about 0.9 TeV at TESLA and 2.6 TeV at CLIC.

  10. DC Breakdown experiments for CLIC

    CERN Document Server

    Descoeudres, A; Taborelli, M

    2008-01-01

    For the production of the Compact Linear Collider (CLIC) RF accelerating structures, a material capable of sustaining high electric field, with a low breakdown rate and showing low damages after breakdowns is needed. A DC breakdown study is underway at CERN in order to test candidate materials and surface preparations. The saturated breakdown fields of several metals and alloys have been measured, ranging from 100 MV/m for Al to 850 MV/m for stainless steel, being around 170 MV/m for Cu and 430 MV/m for Mo for example. The conditioning speed of Mo can be significantly improved by removing oxides at the surface with a vacuum heat treatment, typically at 875±C for 2 hours. DC breakdown rate measurements have been done with Cu and Mo electrodes, showing similar results as in RF experiments: the breakdown probability seems to exponentially increase with the applied field. Measurements of time delays before breakdown show two different populations of breakdowns, immediate and delayed breakdowns, indicating that t...

  11. Single Z' production at CLIC based on e^- gamma collisions

    OpenAIRE

    Soa, D. V.; H.N. Long(Institute of Physics, VAST, 10 Dao Tan, Ba Dinh, Hanoi, Vietnam); Binh, D. T.; Khoi, D. P.

    2003-01-01

    We analyze the potential of CLIC based on e- gamma collisions to search for new $Z'$ gauge boson. Single Z' production at e-gamma colliders in two SU(3)_C X SU(3)_L X U(1)_N models: the minimal model and the model with right-handed (RH) neutrinos is studied in detail. Results show that new Z' gauge bosons can be observed at the CLIC, and the cross sections in the model with RH neutrinos are bigger than those in the minimal one.

  12. Higgs Physics at the CLIC Electron-Positron Linear Collider

    CERN Document Server

    Roloff, Philipp Gerhard

    2016-01-01

    The Compact Linear Collider (CLIC) is an option for a future $e^+e^-$ collider operating at centre-of-mass energies up to 3 TeV, providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper presents the Higgs physics reach of CLIC operating in three energy stages, $\\sqrt{s} =$ 350 GeV, 1.4 TeV and 3 TeV. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ($e^+e^-\\to ZH$) and $WW$-fusion ($e^+e^-\\to H\

  13. Electro-Weak Fits at CLIC

    CERN Document Server

    De Curtis, S

    2002-01-01

    The aim of the future linear colliders is to extend the sensitivity to new physics beyond the reach of the LHC. Several models predict the existence of new vector resonances in the multi-TeV region. We review the existing limits on the masses of these new resonances from LEP/SLC and TEVATRON data and from the atomic parity violation measurements, in some specific models. We study the potential of a multi-TeV e+e- collider, such as CLIC, for the determination of their properties and nature.

  14. Performance of Particle Flow Calorimetry at CLIC

    CERN Document Server

    Marshall, J.S.; Thomson, M.A.

    2013-01-01

    The experimental conditions at CLIC are also significantly more challenging than those at previous electron-positron colliders, with increased levels of beam-induced backgrounds combined with a bunch spacing of only 0.5 ns. This paper describes the modifications made to the PandoraPFA particle flow algorithm to improve the jet energy reconstruction for jet energies above 250 GeV. It then introduces a combination of timing and pT cuts that can be applied to reconstructed particles in order to significantly reduce the background. A systematic study is...

  15. CLIC vertex detector R&D

    Science.gov (United States)

    Alipour Tehrani, Niloufar

    2016-07-01

    A vertex detector concept is under development for the proposed multi-TeV linear e+e- Compact Linear Collider (CLIC). To perform precision physics measurements in a challenging environment, the CLIC vertex detector pushes the technological requirements to the limits. This paper reviews the requirements for the CLIC vertex detector and gives an overview of recent R&D achievements in the domains of sensor, readout, powering and cooling.

  16. Tissue and subcellular distribution of CLIC1

    Directory of Open Access Journals (Sweden)

    Edwards John C

    2007-02-01

    Full Text Available Abstract Background CLIC1 is a chloride channel whose cellular role remains uncertain. The distribution of CLIC1 in normal tissues is largely unknown and conflicting data have been reported regarding the cellular membrane fraction in which CLIC1 resides. Results New antisera to CLIC1 were generated and were found to be sensitive and specific for detecting this protein. These antisera were used to investigate the distribution of CLIC1 in mouse tissue sections and three cultured cell lines. We find CLIC1 is expressed in the apical domains of several simple columnar epithelia including glandular stomach, small intestine, colon, bile ducts, pancreatic ducts, airway, and the tail of the epididymis, in addition to the previously reported renal proximal tubule. CLIC1 is expressed in a non-polarized distribution in the basal epithelial cell layer of the stratified squamous epithelium of the upper gastrointesitinal tract and the basal cells of the epididymis, and is present diffusely in skeletal muscle. Distribution of CLIC1 was examined in Panc1 cells, a relatively undifferentiated, non-polarized human cell line derived from pancreatic cancer, and T84 cells, a human colon cancer cell line which can form a polarized epithelium that is capable of regulated chloride transport. Digitonin extraction was used to distinguish membrane-inserted CLIC1 from the soluble cytoplasmic form of the protein. We find that digitonin-resistant CLIC1 is primarily present in the plasma membrane of Panc1 cells. In T84 cells, we find digitonin-resistant CLIC1 is present in an intracellular compartment which is concentrated immediately below the apical plasma membrane and the extent of apical polarization is enhanced with forskolin, which activates transepithelial chloride transport and apical membrane traffic in these cells. The sub-apical CLIC1 compartment was further characterized in a well-differentiated mouse renal proximal tubule cell line. The distribution of CLIC1 was

  17. Experimental Program for the CLIC test facility 3 test beam line

    CERN Document Server

    Adli, E; Dobert, S; Olvegaard, M; Schulte, D; Syratchev, I; Lillestol, Reidar

    2010-01-01

    The CLIC Test Facility 3 Test Beam Line is the first prototype for the CLIC drive beam decelerator. Stable transport of the drive beam under deceleration is a mandatory component in the CLIC two-beam scheme. In the Test Beam Line more than 50% of the total energy will be extracted from a 150 MeV, 28 A electron drive beam, by the use of 16 power extraction and transfer structures. A number of experiments are foreseen to investigate the drive beam characteristics under deceleration in the Test Beam Line, including beam stability, beam blow up and the efficiency of the power extraction. General benchmarking of decelerator simulation and theory studies will also be performed. Specially designed instrumentation including precision BPMs, loss monitors and a time-resolved spectrometer dump will be used for the experiments. This paper describes the experimental program foreseen for the Test Beam Line, including the relevance of the results for the CLIC decelerator studies.

  18. CLIC Pre-damping and Damping Ring Kickers: Initial Ideas to Achieve Stability Requirements

    CERN Document Server

    Barnes, M J; Uythoven, J

    2010-01-01

    The Compact Linear Collider (CLIC) study is exploring the scheme for an electron-positron collider with high luminosity (1034-1035 cm-2s-1) and a nominal centre-of mass energy of 3 TeV: CLIC would complement LHC physics in the multi-TeV range. The CLIC design relies on the presence of Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve the very low emittance, through synchrotron radiation, needed for the luminosity requirements of CLIC. In order to limit the beam emittance blow-up due to oscillations the combined flat top ripple and droop of the field pulse, for the DR extraction kickers, must be less than 0.02 %. In addition, the allowed beam coupling impedance is also very low: a few Ohms longitudinally and a few MW/m transversally. This paper discusses initial ideas for achieving the demanding requirements for the PDR and DR kickers.

  19. Choke-Mode Damped Structure Design for the CLIC Main Linac

    CERN Document Server

    Zha, Hao; Tang, Chuanxiang; Huang, Wenhui; Shi, Jiaru; Grudiev, Alexej; Wuensch, Walter

    2012-01-01

    Choke-mode damped structures are being studied as an alternative design for the accelerating structures of main linacs of the compact linear collider (CLIC). Choke-mode structures have the potential for much lower pulsed temperature rise, and lower cost of manufacture and fabrication. A new kind of choke-mode structure was proposed and simulated by Gdfidl. This structures has comparable wakefield damping effect as the baseline design of CLIC main linacs.

  20. CLIC5 Stabilizes Membrane-Actin Filament Linkages at the Base of Hair Cell Stereocilia in a Molecular Complex with Radixin, Taperin, and Myosin VI

    OpenAIRE

    Salles, Felipe T.; Andrade, Leonardo R.; Tanda, Soichi; Grati, M’hamed; Plona, Kathleen L.; Gagnon, Leona H.; Johnson, Kenneth R.; Kachar, Bechara; Berryman, Mark A.

    2013-01-01

    Chloride intracellular channel 5 protein (CLIC5) was originally isolated from microvilli in complex with actin binding proteins including ezrin, a member of the Ezrin-Radixin-Moesin (ERM) family of membrane-cytoskeletal linkers. CLIC5 concentrates at the base of hair cell stereocilia and is required for normal hearing and balance in mice, but its functional significance is poorly understood. This study investigated the role of CLIC5 in postnatal development and maintenance of hair bundles. Co...

  1. Impedance effects in the CLIC damping rings

    CERN Document Server

    Koukovini-Platia, E; Mounet, N; Rumolo, G; Salvant, B

    2011-01-01

    Due to the unprecedented brilliance of the beams, the performance of the Compact Linear Collider (CLIC) damping rings (DR) is affected by collective effects. Single bunch instability thresholds based on a broad-band resonator model and the associated coherent tune shifts have been evaluated with the HEADTAIL code. Simulations performed for positive and negative values of chromaticity showed that higher order bunch modes can be potentially dangerous for the beam stability. This study also includes the effects of high frequency resistive wall impedance due to different coatings applied on the chambers of the wigglers for e-cloud mitigation and/or ultra-low vacuum pressure. The impact of the resistive wall wake fields on the transverse impedance budget is finally discussed.

  2. Requirements of CLIC Beam Loss Monitoring System

    CERN Document Server

    Sapinski, M; Holzer, EB; Jonker, M; Mallows, S; Otto, T; Welsch, C

    2010-01-01

    The Compact Linear Collider (CLIC) [1] is a proposed multi-TeV linear electron-positron collider being designed by a world-wide collaboration. It is based on a novel twobeam acceleration scheme in which two beams (drive and main beam) are placed in parallel to each other and energy is transferred from the drive beam to the main one. Beam losses on either of them can have catastrophic consequences for the machine, because of high intensity (drive beam) or high energy and small emittance (main beam). In the framework of machine protection, a Beam Loss Monitoring (BLM) system has to be put in place. This paper discusses the requirements for the beam loss system in terms of detector sensitivity, resolution, dynamic range and ability to distinguish losses originating from various sources. The two-beam module where the protection from beam losses is particularly challenging and important, is studied.

  3. Precision Higgs boson measurement at CLIC

    CERN Document Server

    Pandurovic, Mila

    2016-01-01

    The design of the next generation collider in high energy physics will primarily focus on the possibility to achieve high precision of the measurements of interest. The necessary precision limits are set, in the first place, by the measurement of the Higgs boson but also by measurements that are sensitive to signs of New Physics. The Compact Linear Collider (CLIC) is an attractive option for a future multi-TeV linear electron-positron collider, with the potential to cover a rich physics program with high precision. In this lecture the CLIC accelerator, detector and backgrounds will be presented with emphesis on the capabilities of CLIC for precision Higgs physics.

  4. CLIC's three-step plan

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    In early October, the Compact Linear Collider (CLIC) collaboration published its final Conceptual Design Report. Accompanying it was a strategic summary document that describes a whole new approach to the project: developing the linear e+e− collider in three energy stages. Though CLIC’s future still depends on signs from the LHC, its new staged approach to high-energy electron-positron physics for the post-LHC era is nothing short of convincing.   Instead of asking for a 48-kilometre-long commitment right off the bat, the CLIC collaboration is now presenting an accelerator that can be constructed in stages. For example, it could begin as an 11-kilometre 500 GeV accelerator that could later be extended to a 27-kilometre 1.5 TeV machine. Finally, after a decade or so of data taking, it could be taken up to the full 48-kilometre 3 TeV facility (see image 2). “Not only is the approach technically and financially practical, it also offers a very convincing physics prog...

  5. LHC and CLIC LLRF final reports

    CERN Document Server

    Dexter, A; Woolley, B; Ambattu, P; Tahir, I; Syratchev, Igor; Wuensch, Walter

    2013-01-01

    Crab cavities rotate bunches from opposing beams to achieve effective head-on collision in CLIC or collisions at an adjustable angle in LHC. Without crab cavities 90% of achievable luminosity at CLIC would be lost. In the LHC, the crab cavities allow the same or larger integrated luminosity while reducing significantly the requested dynamic range of physics detectors. The focus for CLIC is accurate phase synchronisation of the cavities, adequate damping of wakefields and modest amplitude stability. For the LHC, the main LLRF issues are related to imperfections: beam offsets in cavities, RF noise, measurement noise in feedback loops, failure modes and mitigations. This report develops issues associated with synchronising the CLIC cavities. It defines an RF system and experiments to validate the approach. It reports on the development of hardware for measuring the phase performance of the RF distributions system and cavities. For the LHC, the hardware being very close to the existing LLRF, the report focuses on...

  6. First phase of CLIC R&D complete

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    Let’s turn back the clocks to 2002: the LHC is still under construction, the wrap-up of the LEP physics programme is still in recent memory and the future of electron-positron accelerators at CERN is ambiguous. It was then that CLIC set out to prove the feasibility of their novel accelerator design in the CTF3 test facility. Though once a tall order for the collaboration, the recently released CLIC Conceptual Design Report has proven many of the major design elements… bringing to an end the first phase of CLIC R&D and pointing toward detailed performance optimisation studies in the next phase.   Streak camera images of the final beam, illustrating the combination of beams in the Combiner Ring. Over a decade ago, the CTF3 team set up shop in the vacated LIL injector site, once home to the weathered machine that delivered electrons and positrons to LEP. Rebuilding and upgrading the machine piece by piece, the CTF3 team converted this mA linac into a high-current drive b...

  7. Golden Jubilee Photos: A CLIC for the future

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ Prototype copper accelerating structures for CLIC. New accelerator projects take many years to make and mature. When the LHC project was still only a twinkle in CERN's eye, research was already starting on a new machine. A small team at CERN was setting about the task of studying a high-energy, compact, lepton linear collider, known as CLIC. This is possibly set to become the collider of the future. A machine of this kind has all the advantages of a collider (the total collision energy is equal to the sum of the energies of the two colliding beams) without the drawback of synchrotron radiation, which is produced when particles are accelerated around a ring and thus puts a limit on the energy of such colliders. But in a project as technically challenging as CLIC, considerable technological hurdles must be overcome. To limit the linear collider's length to some tens of kilometres, the beams must acquire a considerable quantity of energy per metre travelled. The collision rate (lumi...

  8. Sensitivity Analysis for the CLIC Damping Ring Inductive Adder

    CERN Document Server

    Holma, Janne

    2012-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse generators for the damping ring kickers must provide extremely flat, high-voltage pulses. The specifications for the extraction kickers of the CLIC damping rings are particularly demanding: the flattop of the output pulse must be 160 ns duration, 12.5 kV and 250 A, with a combined ripple and droop of not more than ±0.02 %. An inductive adder allows the use of different modulation techniques and is therefore a very promising approach to meeting the specifications. PSpice has been utilised to carry out a sensitivity analysis of the predicted output pulse to the value of both individual and groups of circuit compon...

  9. Measurement of the H$\\rightarrow$WW$^*$ Branching Ratio at 1.4TeV using the semileptonic final state at CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)762723; Watson, Nigel

    2016-01-01

    This note summarises a study to evaluate the potential to measure the H$\\rightarrow$WW$^*$ branching fraction at CLIC, 1.4TeV centre-of-mass energy, with the CLIC_ILD detector, using the WW$\\rightarrow$qql$\

  10. Regulation of the membrane insertion and conductance activity of the metamorphic chloride intracellular channel protein CLIC1 by cholesterol.

    Directory of Open Access Journals (Sweden)

    Stella M Valenzuela

    Full Text Available The Chloride Intracellular ion channel protein CLIC1 has the ability to spontaneously insert into lipid membranes from a soluble, globular state. The precise mechanism of how this occurs and what regulates this insertion is still largely unknown, although factors such as pH and redox environment are known contributors. In the current study, we demonstrate that the presence and concentration of cholesterol in the membrane regulates the spontaneous insertion of CLIC1 into the membrane as well as its ion channel activity. The study employed pressure versus area change measurements of Langmuir lipid monolayer films; and impedance spectroscopy measurements using tethered bilayer membranes to monitor membrane conductance during and following the addition of CLIC1 protein. The observed cholesterol dependent behaviour of CLIC1 is highly reminiscent of the cholesterol-dependent-cytolysin family of bacterial pore-forming proteins, suggesting common regulatory mechanisms for spontaneous protein insertion into the membrane bilayer.

  11. Tunable Achromats and CLIC Applications

    CERN Document Server

    D'Amico, T E

    2000-01-01

    It is imperative for linear colliders that the bunch length be adjustable. In most cases bunch compression is required, but recently, in the design of the Compact LInear Collider (CLIC) RF Power Source, it was shown that bunch stretching may also be necessary. In some situations, both modes may be needed, which implies the need for tunable magnetic insertions. This is even more essential in a test facility, to span a wide experimental range. In addition, flexible tuning provides a better control of the stability of an isochronous insertion. To start a numerical search for a tunable insertion from scratch is very uncertain because the related phase space is very uneven. However, a starting point obtained with an analytical approximation is often sufficient to ensure convergence. Another advantage of the analytical treatment described in this paper is that it sheds light on the shape of the entire phase space. To achieve this the isochronous achromat developed previously has been given tuning capabilities by ex...

  12. Wakefield Damping for the CLIC Crab Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Ambattu, P.K.; Burt, G.; Dexter, A.C.; Carter, R.G.; /Cockcroft Inst. Accel. Sci. Tech. /Lancaster U.; Khan, V.; Jones, R.M.; /Cockcroft Inst. Accel. Sci. Tech. /Manchester U.; Dolgashev, V.; /SLAC

    2011-12-01

    A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

  13. Wakefield damping for the CLIC crab cavity

    CERN Document Server

    Ambattu, P K; Dexter, A C; Carter, R G; Khan, V; Jones, R M; Dolgashev, V

    2009-01-01

    A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

  14. WAKEFIELD DAMPING FOR THE CLIC CRAB CAVITY

    CERN Document Server

    Ambattu, P; Dexter, A; Carter, R; Khan, V; Jones, R; Dolgashev, V

    2009-01-01

    A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

  15. New clic-g structure design

    CERN Document Server

    AUTHOR|(CDS)2082335

    2016-01-01

    The baseline design of the Compact Linear Collider main linac accelerating structure is called ‘CLIC-G’. It is described in the CLIC Conceptual Design Report (CDR) [1]. As shown in Fig. 1, a regular cell of the structure has four waveguides to damp unwanted high-order-modes (HOMs). These waveguides are dimensioned to cut off the fundamental working frequency in order to prevent the degradation of the fundamental mode Q-factor. The cell geometry and HOM damping loads had been extensively optimized in order to maximize the RF-to-beam efficiency, to minimize the cost, and to meet the beam dynamics and the high gradient RF constraints [2

  16. CLIC-ACM: Acquisition and Control System

    CERN Document Server

    Bielawski, B; Magnoni, S

    2014-01-01

    CLIC [1] (Compact Linear Collider) is a world-wide collaboration to study the next terascale lepton collider, relying upon a very innovative concept of two-beamacceleration. In this scheme, the power is transported to the main accelerating structures by a primary electron beam. The Two Beam Module (TBM) is a compact integration with a high filling factor of all components: RF, Magnets, Instrumentation, Vacuum, Alignment and Stabilization. This paper describes the very challenging aspects of designing the compact system to serve as a dedicated Acquisition & Control Module (ACM) for all signals of the TBM. Very delicate conditions must be considered, in particular radiation doses that could reach several kGy in the tunnel. In such severe conditions shielding and hardened electronics will have to be taken into consideration. In addition, with more than 300 ADC&DAC channels per ACM and about 21000 ACMs in total, it appears clearly that power consumption will be an important issue. It is also obvious that...

  17. CLIC quadrupole stabilization and nano-positioning

    CERN Document Server

    Collette, C; Artoos, K; Fernandez Carmona, P; Guinchard, M; Hauviller, C

    2010-01-01

    In the Compact LInear Collider (CLIC) currently under study, electrons and positrons will be accelerated in two linear accelerators to collide at the interaction point with an energy of 0.5- 3 TeV. This machine is constituted of a succession of accelerating structures, used to accelerate the beams of particles, and electromagnets (quadrupoles) used to focus the beams. In order to ensure good performances, the quadrupoles have to be extremely stable. Additionally, they should also have the capability to move by steps of some tens of nanometers every 20 ms with a precision of +/- 1nm. This paper proposes a holistic approach to fulfill alternatively both requirements using the same device. The concept is based on piezoelectric hard mounts to isolate the quadrupoles from the ground vibrations in the sensitive range between 1 and 20 Hz, and to provide nano-positioning capabilities. It is also shown that this strategy ensures robustness to external forces (acoustic noise, water flow for the cooling, air flow for th...

  18. Physics at the CLIC $e^{+}e^{-}$ Linear Collider - Input to the Snowmass process 2013

    CERN Document Server

    Abramowicz, Halina; Afanaciev, K.; Alexander, G.; Alipour Tehrani, N.; Alonso, O.; Andersen, K.K.; Arfaoui, S.; Balazs, C.; Barklow, T.; Battaglia, M.; Benoit, M.; Bilki, B.; Blaising, J.J.; Boland, M.; Boronat, M.; Bozovic Jelisavcic, I.; Burrows, P.; Chefdeville, M.; Contino, R.; Dannheim, D.; Demarteau, M.; Diaz Gutierrez, M.A.; Dieguez, A.; Duarte Campderros, J.; Eigen, G.; Elsener, K.; Feldman, D.; Felzmann, U.; Firlej, M.; Firu, E.; Fiutowski, T.; Francis, K.; Gaede, F.; Garcia Garcia, I.; Ghenescu, V.; Giudice, G.; Graf, N.; Grefe, C.; Grojean, C.; Gupta, R.S.; Hauschild, M.; Holmestad, H.; Idzik, M.; Joram, C.; Kananov, S.; Karyotakis, Y.; Killenberg, M.; Klempt, W.; Kraml, S.; Krupa, B.; Kulis, S.; Lastovicka, T.; LeBlanc, G.; Levy, A.; Levy, I.; Linssen, L.; Lucaci Timoce, A.; Lukic, S.; Makarenko, V.; Marshall, J.; Martin, V.; Mikkelsen, R.E.; Milutinovic-Dumbelovic, G.; Miyamoto, A.; Monig, K.; Moortgat-Pick, G.; Moron, J.; Munnich, A.; Neagu, A.; Pandurovic, M.; Pappadopulo, D.; Pawlik, B.; Porod, W.; Poss, S.; Preda, T.; Rassool, R.; Rattazzi, R.; Redford, S.; Reichold, A.; Repond, J.; Riemann, S.; Robson, A.; Roloff, P.; Ros, E.; Rosten, J.; Ruiz-Jimeno, A.; Rzehak, H.; Sailer, A.; Schlatter, D.; Schulte, D.; Sefkow, F.; Seidel, K.; Shumeiko, N.; Sicking, E.; Simon, F.; Smith, J.; Soldner, C.; Stapnes, S.; Strube, J.; Suehara, T.; Swientek, K.; Szalay, M.; Tanabe, T.; Tesar, M.; Thamm, A.; Thomson, M.; Trenado Garcia, J.; Uggerhoj, U.I.; van der Kraaij, E.; Vila, I.; Vilella, E.; Villarejo, M.A.; Vogel Gonzalez, M.A.; Vos, M.; Watson, N.; Weerts, H.; Wells, J.D.; Weuste, L.; Wistisen, T.N.; Wootton, K.; Xia, L.; Zawiejski, L.; Zgura, I.S.

    2013-01-01

    This paper summarizes the physics potential of the CLIC high-energy e+e- linear collider. It provides input to the Snowmass 2013 process for the energy-frontier working groups on The Higgs Boson (HE1), Precision Study of Electroweak Interactions (HE2), Fully Understanding the Top Quark (HE3), as well as The Path Beyond the Standard Model -- New Particles, Forces, and Dimensions (HE4). It is accompanied by a paper describing the CLIC accelerator study, submitted to the Frontier Capabilities group of the Snowmass process

  19. Physics at the CLIC e$^{+}$e$^{-}$ Linear Collider -- Input to the Snowmass process 2013

    OpenAIRE

    Abramowicz, Halina; Abusleme, Angel; Battaglia, Marco; Świentek, Krzysztof; Szalay, Marco; Tanabe, Tomohiko; Tesař, Michal; Thamm, Andrea; Thomson, Mark; Garcia, Juan Trenado; Uggerhøj, Ulrik I.; van der Kraaij, Erik; Vila, Iván; Benoit, Mathieu; Vilella, Eva

    2013-01-01

    This paper summarizes the physics potential of the CLIC high-energy e+e- linear collider. It provides input to the Snowmass 2013 process for the energy-frontier working groups on The Higgs Boson (HE1), Precision Study of Electroweak Interactions (HE2), Fully Understanding the Top Quark (HE3), as well as The Path Beyond the Standard Model -- New Particles, Forces, and Dimensions (HE4). It is accompanied by a paper describing the CLIC accelerator study, submitted to the Frontier Capabilities gr...

  20. Energy and Beam-Offset dependence of the Luminosity weighted depolarization for CLIC

    CERN Document Server

    Esberg, Jakob; Uggerhoj, Ulrik; Dalena, Barbara

    2011-01-01

    We report on simulations of e+e- depolarization due to beam-beam effects. These effects are studied for CLIC at 3 TeV, using GUINEA PIG++. We find a strong energy dependence of the luminosity weighted depolarization. In the luminosity peak at CLIC the total luminosity weighted depolarization remains below the one per-mil level. The effect of a vertical offset on the energy dependent depolarization is investigated. The depolarization in the luminosity peak remains below per-cent level even for 5sy offsets.

  1. Highlights from CERN: The CLIC Project for a Future e$^{+}$e$^{−}$ Linear Collider

    CERN Document Server

    Tecker, Frank

    2007-01-01

    A high luminosity ( 10$^{34}$-10$^{35}$ cm$^{2}$/s) linear electron-positron Collider (CLIC) with a nominal centre-of-mass energy of 3 TeV is under study in the framework of an international collaboration of laboratories and institutes, with the aim to provide the HEP community with a new facility for the post LHC era. After a brief introduction of the physics motivation, the CLIC scheme to extend Linear Colliders into the Multi-TeV colliding beam energy range will be described. In the following, the main challenges and the very promising achievements already obtained will be presented.

  2. Physics potential of the BR(H →WW∗) measurement at a √s=350 GeV and √s=1.4 TeV CLIC collider

    CERN Document Server

    Pandurovic, Mila

    2016-01-01

    Precision measurements of the number of properties of the Higgs boson, like invariant mass and couplings to the Standard Model particles, represent one of the key measurements of the CLIC physic program. The CLIC energy staging scenario allows to perform these meas- urements using different Higgs production channels. The Higgs decay to a WW pair, which is analysed at two CLIC energy stages, plays an important role in this program, as it gives access to the relative Higgs couplings to the vector bosons and to the total Higgs decay width. The studies presented here are part of an ongoing effort to investigate the full physics potential of the CLIC collider.

  3. CLIC preparations go up a notch

    CERN Multimedia

    2007-01-01

    The Compact Linear Collider gears up for post-LHC physics with an international workshop. A schematic diagram of CLIC.In June CERN gained a new building: number 2010. And as chance would have it, this is more than just a number to its new residents. By the year 2010, teams working at the new CLIC Experimental Area, along with the already established CLIC Test Facility Three (CTF3), hope to have demonstrated the feasibility of the Compact Linear Collider and, depending on results from the LHC, embark on its final design and proposal. A workshop on 16t-18 October brought people from all around the world to CERN to exchange ideas and hear how the ambitious project is progressing. CLIC is a project that aims to extend lepton collider technology to multi-TeV energy physics, colliding leptons with a centre-of-mass-energy up to 3TeV, more than ten times the energy of the LEP. This is only possible in a linear collider, where no energy is lo...

  4. On structure design for the CLIC Booster Linac

    CERN Document Server

    Darvish, Esmat

    2015-01-01

    Using the SUPERFISH code we present a design for a traveling wave (TW) structure of the Booster Linac for CLIC. The structure, consisting of thirty asymmetric cells attached to the beam pipes at two ends, works in 2π/3 operating mode at working frequency 2 GHz. For the corresponding operating mode and frequency, the RF field configuration transmitted through the cavity is obtained. The results are prepared in an RF field data file to be used in the PARMELA code for further beam dynamic study.

  5. 全球气候研究计划(WCRP)中的气候与冰冻圈项目(CliC): 冰冻圈与气候的优先研究领域%The World Climate Research Programme (WCRP) Climate and Cryosphere Project (CliC): Priority Studies of the Cryosphere and Climate

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The cryosphere is an integral part of the global climate system, however, many aspects of the cryosphere have not been fully covered within WCRP. Issues relating to potential changes in the climate cryosphere system become more and more important in order to describes research and coordination initiatives required to integrate fully studies of impact and response of the cryosphere to climate change. The article also indicates the recent progress of CliC, and its future plan.

  6. Benchmarking of the Placet and Dimad tracking codes using the CLIC Post-Collision line

    CERN Document Server

    Ahmed, I; Ferrari, A; Latina, A

    2009-01-01

    In this benchmarking study, two contemporary codes, DIMAD and PLACET, are compared. We consider the 20 mrad post-collision line of the Compact Linear Collider (CLIC) and perform tracking studies of heavily disrupted post-collision electron beams. We successfully find that the two codes provide an equivalent description of the beam transport from the interaction point to the final dump.

  7. Higgs Physics at the CLIC Electron-Positron Linear Collider

    CERN Document Server

    Abramowicz, H; Afanaciev, K; Tehrani, N Alipour; Balázs, C; Benhammou, Y; Benoit, M; Bilki, B; Blaising, J -J; Boland, M J; Boronat, M; Borysov, O; Božović-Jelisavčić, I; Buckland, M; Bugiel, S; Burrows, P N; Charles, T K; Daniluk, W; Dannheim, D; Dasgupta, R; Demarteau, M; Gutierrez, M A Díaz; Eigen, G; Elsener, K; Felzmann, U; Firlej, M; Firu, E; Fiutowski, T; Fuster, J; Gabriel, M; Gaede, F; García, I; Ghenescu, V; Goldstein, J; Green, S; Grefe, C; Hauschild, M; Hawkes, C; Hynds, D; Idzik, M; Kačarević, G; Kalinowski, J; Kananov, S; Klempt, W; Kopec, M; Krawczyk, M; Krupa, B; Kucharczyk, M; Kulis, S; Laštovička, T; Lesiak, T; Levy, A; Levy, I; Linssen, L; Lukić, S; Maier, A A; Makarenko, V; Marshall, J S; Mei, K; Milutinović-Dumbelović, G; Moroń, J; Moszczyński, A; Moya, D; Münker, R M; Münnich, A; Neagu, A T; Nikiforou, N; Nikolopoulos, K; Nürnberg, A; Pandurović, M; Pawlik, B; Codina, E Perez; Peric, I; Petric, M; Pitters, F; Poss, S G; Preda, T; Protopopescu, D; Rassool, R; Redford, S; Repond, J; Robson, A; Roloff, P; Ros, E; Rosenblat, O; Ruiz-Jimeno, A; Sailer, A; Schlatter, D; Schulte, D; Shumeiko, N; Sicking, E; Simon, F; Simoniello, R; Sopicki, P; Stapnes, S; Ström, R; Strube, J; Świentek, K P; Szalay, M; Tesař, M; Thomson, M A; Trenado, J; Uggerhøj, U I; van der Kolk, N; van der Kraaij, E; Pinto, M Vicente Barreto; Vila, I; Gonzalez, M Vogel; Vos, M; Vossebeld, J; Watson, M; Watson, N; Weber, M A; Weerts, H; Wells, J D; Weuste, L; Winter, A; Wojtoń, T; Xia, L; Xu, B; Żarnecki, A F; Zawiejski, L; Zgura, I -S

    2016-01-01

    The Compact Linear Collider (CLIC) is an option for a future e+e- collider operating at centre-of-mass energies up to 3 TeV, providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper presents the Higgs physics reach of CLIC operating in three energy stages, sqrt(s) = 350 GeV, 1.4 TeV and 3 TeV. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung (e+e- -> ZH) and WW-fusion (e+e- -> Hnunu), resulting in precise measurements of the production cross sections, the Higgs total decay width Gamma_H, and model-independent determinations of the Higgs couplings. Operation at sqrt(s) > 1 TeV provides high-statistics samples of Higgs bosons produced through WW-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes e+e- -> ttH and e+e- -> HHnunu would allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of...

  8. Brilliant positron sources for CLIC and other collider projects

    CERN Document Server

    Rinolfi, Louis; Dadoun, Olivier; Kamitani, Takuya; Strakhovenko, Vladimir; Variola, Alessandro

    2013-01-01

    The CLIC (Compact Linear Collider), as future linear collider, requires an intense positron source. A brief history is given up to the present baseline configuration which assumes unpolarized beams. A conventional scheme, with a single tungsten target as source of e-e+ pairs, has been studied several years ago. But, in order to reduce the beam energy deposition on the e+ target converter, a double-target system has been studied and proposed as baseline for CLIC. With this ‘‘hybrid target’’, the positron production scheme is based on the channeling process. A 5 GeV electron beam impinges on a thin crystal tungsten target aligned along its axis, enhancing the photon production by channeling radiation. A large number of photons are sent to a thick amorphous tungsten target, generating large number of e-e+ pairs, while the charged particles are bent away, reducing the deposited energy and the PEDD (Peak Energy Deposition Density). The targets parameters are optimized for the positron production. Polarize...

  9. Cherenkov Fibers for Beam Loss Monitoring at the CLIC Two Beam Module

    CERN Document Server

    van Hoorne, Jacobus Willem; Holzer, E B

    The Compact Linear Collider (CLIC) study is a feasibility study aiming at a nominal center of mass energy of 3TeV and is based on normal conducting travelling-wave accelerating structures, operating at very high field gradients of 100 MV/m. Such high fields require high peak power and hence a novel power source, the CLIC two beam system, has been developed, in which a high intensity, low energy drive beam (DB) supplies energy to a high energy, low intensity main beam (MB). At the Two Beam Modules (TBM), which compose the 2x21km long CLIC main linac, a protection against beam losses resulting from badly controlled beams is necessary and particularly challenging, since the beam power of both main beam (14 MW) and drive beam (70 MW) is impressive. To avoid operational downtimes and severe damages to machine components, a general Machine Protection System (MPS) scheme has been developed. The Beam Loss Monitoring (BLM) system is a key element of the CLIC machine protection system. Its main role will be to detect p...

  10. Development and testing of a double length pets for the CLIC experimental area

    Science.gov (United States)

    Sánchez, L.; Carrillo, D.; Gavela, D.; Lara, A.; Rodríguez, E.; Gutiérrez, J. L.; Calero, J.; Toral, F.; Samoshkin, A.; Gudkov, D.; Riddone, G.

    2014-05-01

    CLIC (compact linear collider) is a future e+e- collider based on normal-conducting technology, currently under study at CERN. Its design is based on a novel two-beam acceleration scheme. The main beam gets RF power extracted from a drive beam through power extraction and transfer structures (PETS). The technical feasibility of CLIC is currently being proved by its Third Test Facility (CTF3) which includes the CLIC experimental area (CLEX). Two Double Length CLIC PETS will be installed in CLEX to validate their performance with beam. This paper is focused on the engineering design, fabrication and validation of this PETS first prototype. The design consists of eight identical bars, separated by radial slots in which damping material is located to absorb transverse wakefields, and two compact couplers placed at both ends of the bars to extract the generated power. The PETS bars are housed inside a vacuum tank designed to make the PETS as compact as possible. Several joint techniques such as vacuum brazing, electron beam and arc welding were used to complete the assembly. Finally, several tests such as dimensional control and leak testing were carried out to validate design and fabrication methods. In addition, RF measurements at low power were made to study frequency tuning.

  11. CLIC Post-Collision Line Luminosity Monitoring

    CERN Document Server

    Appleby, R B; Deacon, L; Geschwendtner, E

    2011-01-01

    The CLIC post collision line is designed to transport the un-collided beams and the products of the collided beams with a total power of 14MW to the main beam dump. Full Monte Carlo simulation has been done for the description of the CLIC luminosity monitoring in the post collision line. One method of the luminosity diagnostic is based on the detection of high energy muons produced by beamstrahlung photons in the main beam dump. The disrupted beam and the beamstrahlung photons produce at the order of 106 muons per bunch crossing per cm2, with energies higher than 10 GeV. Threshold Cherenkov counters are considered after the beam dump for the detection of these high energy muons. Another method for luminosity monitoring is presented using the direct detection of the beamstrahlung photons.

  12. Preliminary Design of an Inductive Adder for CLIC Damping Rings

    CERN Document Server

    Holma, J

    2011-01-01

    The Compact Linear Collider (CLIC) study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping rings kickers must provide extremely flat, high-voltage, pulses: specifications call for a 160 ns duration flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 %. A solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications; this topology allows the use of both digital and analogue modulation. To effectively use modulation techniques to achieve such low ripple and droop requires an in-depth knowledge of the behaviour of the solid-state switching components and their gate drivers, as well as a good understanding of the overa...

  13. Development and testing of a double length pets for the CLIC experimental area

    CERN Document Server

    Sánchez, L; Gavela, D; Lara, A; Rodríguez, E; Gutiérrez, J L; Calero, J; Toral, F; Samoshkin, A; Gudkov, D; Riddone, G

    2014-01-01

    CLIC (compact linear collider) is a future e þ e collider based on normal-conducting technology, currently under study at CERN. Its design is based on a novel two-beam acceleration scheme. The main beam gets RF power extracted from a drive beam through power extraction and transfer structures (PETS). The technical feasibility of CLIC is currently being proved by its Third Test Facility (CTF3) which includes the CLIC experimental area (CLEX). Two Double Length CLIC PETS will be installed in CLEX to validate their performance with beam. This paper is focused on the engineering design, fabrication and validation of this PETS fi rst prototype. The design consists of eight identical bars, separated by radial slots in which damping material is located to absorb transverse wake fi elds, and two compact couplers placed at both ends of the bars to extract the generated power. The PETS bars are housed inside a vacuum tank designed to make the PETS as compact as possible. Several joint techniques such as vacuum brazing...

  14. Submicron multi-bunch BPM for CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Schmickler, H.; Soby, L.; /CERN; Lunin, A.; Solyak, N.; Wendt, M.; /Fermilab

    2010-08-01

    A common-mode free cavity BPM is currently under development at Fermilab within the ILC-CLIC collaboration. This monitor will be operated in a CLIC Main Linac multi-bunch regime, and needs to provide both, high spatial and time resolution. We present the design concept, numerical analysis, investigation on tolerances and error effects, as well as simulations on the signal response applying a multi-bunch stimulus. The proposed CERN linear collider (CLIC) requires a very precise measurement of beam trajectory to preserve the low emittance when transporting the beam through the Main Linac. An energy chirp within the bunch train will be applied to measure and minimize the dispersion effects, which require high resolution (in both, time and space) beam position monitors (BPM) along the beam-line. We propose a low-Q waveguide loaded TM{sub 110} dipole mode cavity as BPM, which is complemented by a TM{sub 010} monopole mode resonator of same resonant frequency for reference signal purposes. The design is based on a well known TM{sub 110} selective mode coupling idea.

  15. Expression, purification, crystallization and preliminary X-ray diffraction analysis of chloride intracellular channel 2 (CLIC2)

    International Nuclear Information System (INIS)

    Chloride intracellular channel 2 (CLIC2) belongs to a family of intracellular chloride-channel proteins that can exist in a soluble form. The expression, purification and crystallization in two different crystal forms of human CLIC2 is reported. The chloride intracellular channel (CLIC) family of proteins are unusual in that they can exist in either an integral membrane-channel form or a soluble form. Here, the expression, purification, crystallization and preliminary diffraction analysis of CLIC2, one of the least-studied members of this family, are reported. Human CLIC2 was crystallized in two different forms, both in the presence of reduced glutathione and both of which diffracted to better than 1.9 Å resolution. Crystal form A displayed P212121 symmetry, with unit-cell parameters a = 44.0, b = 74.7, c = 79.8 Å. Crystal form B displayed P21 symmetry, with unit-cell parameters a = 36.0, b = 66.9, c = 44.1 Å. Structure determination will shed more light on the structure and function of this enigmatic family of proteins

  16. From glutathione transferase to pore in a CLIC

    CERN Document Server

    Cromer, B A; Morton, C J; Parker, M W; 10.1007/s00249-002-0219-1

    2002-01-01

    Many plasma membrane chloride channels have been cloned and characterized in great detail. In contrast, very little is known about intracellular chloride channels. Members of a novel class of such channels, called the CLICs (chloride intracellular channels), have been identified over the last few years. A striking feature of the CLIC family of ion channels is that they can exist in a water- soluble state as well as a membrane-bound state. A major step forward in understanding the functioning of these channels has been the recent crystal structure determination of one family member, CLIC1. The structure confirms that CLICs are members of the glutathione S- transferase superfamily and provides clues as to how CLICs can insert into membranes to form chloride channels. (69 refs).

  17. A CLIC-Prototype Higgs Factory

    OpenAIRE

    Belusevic, Radoje; Higo, Toshiyasu

    2012-01-01

    We propose that a pair of electron linacs with high accelerating gradients and an optical FEL be built at an existing laboratory. The linacs would employ CLIC-type rf cavities and a klystron-based power source; a two-beam scheme could be implemented at a later stage. The proposed facility would serve primarily as an e+e-/gamma-gamma Higgs-boson factory. The rich set of final states in e+e- and gamma-gamma collisions would play an essential role in measuring the mass, spin, parity, two-photon ...

  18. Conceptual Design for CLIC Gun Pulser

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Tao [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2016-01-08

    The Compact Linear Collider (CLIC) is a proposed future electron-positron collider, designed to perform collisions at energies from 0.5 to 5 TeV, with a nominal design optimized for 3 TeV (Dannheim, 2012). The Drive Beam Accelerator consists of a thermionic DC gun, bunching section and an accelerating section. The thermionic gun needs deliver a long (~143us) pulse of current into the buncher. A pulser is needed to drive grid of the gun to generate a stable current output. This report explores the requirements of the gun pulser and potential solutions to regulate grid current.

  19. PACMAN – an Innovative Doctoral Programme for CLIC

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    The final network project funded under the European Commission’s Seventh Framework Programme (FP7), Marie Curie Actions, held its kick-off meeting at CERN on 20 November 2013.   PACMAN – a study on Particle Accelerator Components Metrology and Alignment to the Nanometre scale – is in the final stage of recruiting 10 PhD students to do research on beam instrumentation, metrology, micrometric alignment, magnetic measurements, nano-positioning and high-precision engineering. The students will acquire multi-disciplinary expertise in advanced engineering combined with a broad span of transferable skills. “PACMAN gives us the opportunity to attract students to CERN at a key moment in the CLIC study,” said Frédérick Bordry, Head of CERN’s Technology Department. “This is also an ideal opportunity to further develop CERN’s networks with industry and universities.” “The project is...

  20. CLIC5 stabilizes membrane-actin filament linkages at the base of hair cell stereocilia in a molecular complex with radixin, taperin, and myosin VI.

    Science.gov (United States)

    Salles, Felipe T; Andrade, Leonardo R; Tanda, Soichi; Grati, M'hamed; Plona, Kathleen L; Gagnon, Leona H; Johnson, Kenneth R; Kachar, Bechara; Berryman, Mark A

    2014-01-01

    Chloride intracellular channel 5 protein (CLIC5) was originally isolated from microvilli in complex with actin binding proteins including ezrin, a member of the Ezrin-Radixin-Moesin (ERM) family of membrane-cytoskeletal linkers. CLIC5 concentrates at the base of hair cell stereocilia and is required for normal hearing and balance in mice, but its functional significance is poorly understood. This study investigated the role of CLIC5 in postnatal development and maintenance of hair bundles. Confocal and scanning electron microscopy of CLIC5-deficient jitterbug (jbg) mice revealed progressive fusion of stereocilia as early as postnatal day 10. Radixin (RDX), protein tyrosine phosphatase receptor Q (PTPRQ), and taperin (TPRN), deafness-associated proteins that also concentrate at the base of stereocilia, were mislocalized in fused stereocilia of jbg mice. TPRQ and RDX were dispersed even prior to stereocilia fusion. Biochemical assays showed interaction of CLIC5 with ERM proteins, TPRN, and possibly myosin VI (MYO6). In addition, CLIC5 and RDX failed to localize normally in fused stereocilia of MYO6 mutant mice. Based on these findings, we propose a model in which these proteins work together as a complex to stabilize linkages between the plasma membrane and subjacent actin cytoskeleton at the base of stereocilia. PMID:24285636

  1. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    CERN Document Server

    Alipour Tehrani, Niloufar; Benoit, Mathieu; Dannheim, Dominik; Dette, Karola; Hynds, Daniel; Kulis, Szymon; Peric, Ivan; Petric, Marko; Redford, Sophie; Sicking, Eva; Valerio, Pierpaolo

    2015-01-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor. Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  2. M10.3.4: CLIC crab cavity specifications completed

    CERN Document Server

    Dexter, A; Ambattu, P; Shinton, I; Jones, R

    2010-01-01

    The starting point of Sub-task 2 is to document the currently anticipated requirements for the CLIC crab cavity system. This milestone concerns completion of the basic specifications for the CLIC crab cavity system. This comprises kick, power requirement, phase and amplitude stability, technology choice, and RF layout. The wakefield calculations of a baseline CLIC cavity will be used to estimate the required damping of the higher order modes as well as other special modes in crab cavities (the lower and same order modes).

  3. CLIC CRAB CAVITY SPECIFICATIONS MILESTONE: M10.3.4

    CERN Document Server

    Ambattu, P; Dexter, A; Jones, R; McIntosh, P; Shinton, I

    2010-01-01

    The starting point of Sub-task 2 is to document the currently anticipated requirements for the CLIC crab cavity system. This milestone concerns completion of the basic specifications for the CLIC crab cavity system. This comprises kick, power requirement, phase and amplitude stability, technology choice, and RF layout. The wakefield calculations of a baseline CLIC cavity will be used to estimate the required damping of the higher order modes as well as other special modes in crab cavities (the lower and same order modes).

  4. Implications of a Curved Tunnel for the Main Linac of CLIC

    CERN Document Server

    Latina, Andrea; Schulte, Daniel

    2006-01-01

    Preliminary studies of a linac that follows the earth curvature are presented for the CLIC main linac. The curvature of the tunnel is modeled in a realistic way by use of geometry changing elements. The emittance preservation is studied for a perfect machine as well as taking into account imperfections. Results for a curved linac are compared with those for a laser-straight machine.

  5. Summary of the BDS and MDI CLIC08 Working Group

    CERN Document Server

    Tomás, R; Ahmed, I; Ambatu, PK; Angal-Kalinin, D; Barlow, R; Baud, J P; Bolzon, B; Braun, H; Burkhardt, H; Burt, GC; Corsini, R; Dalena, B; Dexter, AC; Dolgashev, V; Elsener, K; Fernandez Hernando, JL; Gaillard, G; Geffroy, N; Jackson, F; Jeremie, A; Jones, RM; McIntosh, P; Moffeit, K; Peltier, F; Resta-López, J; Rumolo, G; Schulte, D; Seryi, A; Toader, A; Zimmermann, F

    2008-01-01

    This note summarizes the presentations held within the Beam Delivery System and Machine Detector Interface working group of the CLIC08 workshop. The written contributions have been provided by the presenters on a voluntary basis.

  6. Parameter scan for the CLIC Damping rings under the infleunce of intrabeam scattering

    CERN Document Server

    Antoniou, F; Papaphilippou, Y; Vivoli, A

    2010-01-01

    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, the bench-marking of the multiparticle tracking code SIRE with the classical IBS formalisms and approximations is first considered. The scaling of the steady state emittances and IBS growth rates is also studied, with respect to several ring parameters including energy, bunch charge and wiggler characteristics.

  7. Nonlinear Optimization of CLIC DRS New Design with Variable Bends and High Field Wigglers

    CERN Document Server

    Ghasem, H.; Alabau-Gonzalvo, J.; Papadopoulou, S.; Papaphilippou, Y.

    2016-01-01

    The new design of CLIC damping rings is based on longitudinal variable bends and high field superconducting wiggler magnets. It provides an ultra-low horizontal normalised emittance of 412 nm-rad at 2.86 GeV. In this paper, nonlinear beam dynamics of the new design of the damping ring (DR) with trapezium field profile bending magnets have been investigated in detail. Effects of the misalignment errors have been studied in the closed orbit and dynamic aperture.

  8. The CLIC project and the design for an e+- collider

    International Nuclear Information System (INIS)

    The two-beam scheme of the CERN Linear Collider (CLIC) project is discussed. The problems in achieving the needed luminosity, caused by disruption and beam radiation are outlined. The main CLIC paramaters are presented. The supply of the RF power and problems of RF focusing caused by wakefield effects are discussed. The transfer and main LINAC structures, and the design of damping rings and the final focus are outlined. (H.W.). 25 refs.; 3 figs.; 2 tabs

  9. A high resolution cavity BPM for the CLIC Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Chritin, N.; Schmickler, H.; Soby, L.; /CERN; Lunin, A.; Solyak, N.; Wendt, M.; Yakovlev, V.; /Fermilab

    2010-08-01

    In frame of the development of a high resolution BPM system for the CLIC Main Linac we present the design of a cavity BPM prototype. It consists of a waveguide loaded dipole mode resonator and a monopole mode reference cavity, both operating at 15 GHz, to be compatible with the bunch frequencies at the CLIC Test Facility. Requirements, design concept, numerical analysis, and practical considerations are discussed.

  10. Optimal Power System and Grid Interface Design Considerations for the CLICs Klystron Modulators

    CERN Document Server

    Marija, Jankovic; Jon, Clare; Pat, Wheeler; Davide, Aguglia

    2015-01-01

    The Compact Linear Collider (CLIC) is an electron-positron collider under study at CERN with the aim to explore the next generation of high precision/high energy particles physics. The CLIC’s drive beams will be accelerated by approximately 1300 klystrons, requiring highly efficient and controllable solid state capacitor discharge modulators. Capacitor charger specifications include the requirement to mask the pulsed effect of the load from the utility grid, ensure maximum power quality, control the derived DC voltage precisely (to maximize accuracy for the modulators being implemented), and achieve high efficiency and operability of the overall power system. This paper presents the work carried out on the power system interface for the CLIC facility. In particular it discusses the challenges on the utility interface and analysis of the grid interface converters with regards to required functionality, efficiency, and control methodologies.

  11. Stabilization of the Beam Intensity in the Linac at the CTF3 CLIC Test Facility

    CERN Document Server

    Dubrovskiy, A; Bathe, BN; Srivastava, S

    2013-01-01

    A new electron beam stabilization system has been introduced in CTF3 in order to open new possibilities for CLIC beam studies in ultra-stable conditions and to provide a sustainable tool to keep the beam intensity and energy at its reference values for long term operations. The stabilization system is based on a pulse-to-pulse feedback control of the electron gun to compensate intensity deviations measured at the end of the injector and at the beginning of the linac. Thereby it introduces negligible beam distortions at the end of the linac and it significantly reduces energy deviations. A self-calibration mechanism has been developed to automatically configure the feedback controller for the optimum performance. The residual intensity jitter of 0.045% of the stabilized beam was measured whereas the CLIC requirement is 0.075%.

  12. Production of excited electrons at TESLA and CLIC based egamma colliders

    CERN Document Server

    Kirca, Z; Cakir, O

    2003-01-01

    We analyze the potential of TESLA and CLIC based electron-photon colliders to search for excited spin-1/2 electrons. The production of excited electrons in the resonance channel through the electron- photon collision and their subsequent decays to leptons and electroweak gauge bosons are investigated. We study in detail the three signal channels of excited electrons and the corresponding backgrounds through the reactions egamma yields egamma, egamma yields eZ and egamma yields vW. Excited electrons with masses up to about 90% of the available collider energy can be probed down to the coupling f = f prime = 0.05(0.1) at TESLA(CLIC) based egamma colliders. 22 Refs.

  13. TCAD simulations of High-Voltage-CMOS Pixel structures for the CLIC vertex detector

    CERN Document Server

    Buckland, Matthew Daniel

    2016-01-01

    The requirements for precision physics and the experimental conditions at CLIC result in stringent constraints for the vertex detector. Capacitively coupled active pixel sensors with 25 μm pitch implemented in a commercial 180 nm High-Voltage CMOS (HV-CMOS) process are currently under study as a candidate technology for the CLIC vertex detector. Laboratory calibration measurements and beam tests with prototypes are complemented by detailed TCAD and electronic circuit simulations, aiming for a comprehensive understanding of the signal formation in the HV-CMOS sensors and subsequent readout stages. In this note 2D and 3D TCAD simulation results of the prototype sensor, the Capacitively Coupled Pixel Detector version three (CCPDv3), will be presented. These include the electric field distribution, leakage current, well capacitance, transient response to minimum ionising particles and charge-collection.

  14. On-Line Dispersion Free Steering for the Main Linac of CLIC

    CERN Document Server

    Pfingstner, J

    2013-01-01

    For future linear colliders as well as for light sources, ground motion effects are a severe problem for the accelerator performance. After a few minutes, orbit feedback systems are not sufficient to mitigate all ground motion effects and additional long term methods will have to be deployed. In this paper, the long term ground motion effects in the main linac of the Compact Linear Collider (CLIC) are analysed via simulation studies. The primary growth of the projected emittance is identified to originate from chromatic dilutions due to dispersive beam orbits. To counter this effect, an on-line identification algorithm is applied to measure the dispersion parasitically. This dispersion estimate is used to correct the beam orbit with an iterative dispersion free steering algorithm. The presented results are not only of interest for the CLIC project, but for all linacs in which the dispersive orbit has to be corrected over time.

  15. Thermo-mechanical Analysis of the CLIC Post-Linac Energy Collimators

    CERN Document Server

    Resta-Lopez, J; Latina, A

    2012-01-01

    The post-linac energy collimation system of the Compact Linear Collider (CLIC) has been designed for passive protection of the Beam Delivery System (BDS) against miss-steered beams due to failure modes in the main linac. In this paper, a thermo-mechanical analysis of the CLIC energy collimators is presented. This study is based on simulations using the codes FLUKA and ANSYS when an entire bunch train hits the collimators. Different failure mode scenarios in the main linac are considered. The aim is to improve the collimator in order to make a reliable and robust design so that survives without damage the impact of a full bunch train in case of likely events generating energy errors.

  16. Power pulsing scheme for analog and digital electronics of the vertex detectors at CLIC

    CERN Document Server

    Blanchot, Georges

    2015-01-01

    The precision requirements of the vertex detector at CLIC impose strong limitations on the mass of such a detector (< 0.2% of a radiation length, Xo, per layer). To achieve such a low material budget, ultra-thin hybrid pixel detectors are foreseen, while the mass for cooling and services will be reduced by implementing a power pulsing scheme that takes advantage of the low duty cycle of the accelerator. The principal aim is to achieve significant power reduction without compromising the power integrity supplied to the front-end electronics. This report summarises the study of a power pulsing scheme to power the vertex barrel electronics of the future CLIC experiment. Its main goal is to describe in more detail what has been already presented in TWEPP conferences and other presentations. The report can therefore serve as an operator manual for future use and development of the system

  17. Wakefield monitor development for CLIC accelerating structure

    CERN Document Server

    Peauger, F; Girardot, P; Andersson, A; Riddone, G; Samoshkin, A; Solodko, A; Zennaro, R; Ruber, R

    2010-01-01

    Abstract To achieve high luminosity in CLIC, the accelerating structures must be aligned to an accuracy of 5 μm with respect to the beam trajectory. Position detectors called Wakefield Monitors (WFM) are integrated to the structure for a beam based alignment. This paper describes the requirements of such monitors. Detailed RF design and electromagnetic simulations of the WFM itself are presented. In particular, time domain computations are performed and an evaluation of the resolution is done for two higher order modes at 18 and 24 GHz. The mechanical design of a prototype accelerating structure with WFM is also presented as well as the fabrication status of three complete structures. The objective is to implement two of them in CTF3 at CERN for a feasibility demonstration with beam and high power rf.

  18. A CLIC-Prototype Higgs Factory

    CERN Document Server

    Belusevic, Radoje

    2012-01-01

    We propose that a pair of electron linacs with high accelerating gradients and an optical FEL be built at an existing laboratory. The linacs would employ CLIC-type rf cavities and a klystron-based power source; a two-beam scheme could be implemented at a later stage. The proposed facility would serve primarily as an e+e-/gamma-gamma Higgs-boson factory. The rich set of final states in e+e- and gamma-gamma collisions would play an essential role in measuring the mass, spin, parity, two-photon width and trilinear self-coupling of the Higgs-boson, as well as its couplings to fermions and gauge bosons. These quantities are difficult to determine with only one initial state. For some processes within and beyond the Standard Model, the required CM energy is considerably lower at the proposed facility than at an e+e- or proton collider.

  19. Conceptual Design of the CLIC Damping Rings

    CERN Document Server

    Papaphilippou, Y; Barnes, M; Calatroni, S; Chiggiato, P; Corsini, R; Grudiev, A; Koukovini, E; Lefevre, T; Martini, M; Modena, M; Mounet, N; Perin, A; Renier, Y; Russenschuck, S; Rumolo, G; Schoerling, D; Schulte, D; Schmickler, H; Taborelli, M; Vandoni, G; Zimmermann, F; Zisopoulos, P; Boland, M; Palmer, M; Bragin, A; Levichev, E; Syniatkin, S; Zolotarev, K; Vobly, P; Korostelev, M; Vivoli, A; Belver-Aguilar, C; Faus-Golfe, A; Rinolfi, L; Bernhard, A; Pivi, M; Smith, S; Rassool, R; Wootton, K

    2012-01-01

    The CLIC Damping rings are designed to produce unprecedentedly low-emittances of 500 nm and 5 nm normalized at 2.86 GeV, with high bunch charge, necessary for the performance of the collider. The large beam brightness triggers a number of beam dynamics and technical challenges. Ring parameters such as energy, circumference, lattice, momentum compaction, bending and superconducting wiggler fields are carefully chosen in order to provide the target emittances under the influence of intrabeam scattering but also reduce the impact of collective effects such as space-charge and coherent synchrotron radiation. Mitigation techniques for two stream instabilities have been identified and tested. The low vertical emittance is achieved by modern orbit and coupling correction techniques. Design considerations and plans for technical systems, such as wigglers, transfer systems, vacuum, RF cavities, instrumentation and feedback are finally reviewed.

  20. Simulations for CLIC Drive Beam Linac

    CERN Document Server

    Aksoy, Avni

    2012-01-01

    The Drive Beam Linac of the Compact Linear Collider (CLIC) has to accelerate an electron beam with 4.2 A up to 2.4 GeV in almost fully-loaded structures. The pulse contains about 70000 bunches, one in every second rf bucket, and has a length of 140 $\\mu$s. The beam stability along the beamline is of concern for such a high current and pulse length. We present different options for the lattice of the linac based on FODO, triplet and doublet cells and compare the transverse instability for each lattice including the effects of beam jitter, alignment and beam-based correction. Additionally longitudinal stability is discussed for different bunch compressors using FODO type of lattice.

  1. High performance electronics for alignment regulation on the CLIC 30GHz modules

    International Nuclear Information System (INIS)

    CERN is studying a linear collider (CLIC) to obtain electron-positron collisions with centre-of-mass energies in the TeV range. To demonstrate the feasibility of CLIC, a test facility (CTF2) is being constructed. CTF2 consists of 4 identical modules, each 1.4 m long module consists of 2 linac with a girder and a doublet or a triplet quadrupole. Girders are elements that support mechanically the cavities of the accelerator while the main objective of the quadrupole is to focus particle beams. The alignment system has 2 principal utilities. The first is to pre-align the elements to make the beam pass through the aperture and produce signals in beam position monitors. In respect to these signals the girders and the quadrupoles are moved for making the definitive alignment. The second utility is to maintain the elements in this position. The alignment control system of CTF2 must regulate the position of the girders and quadrupoles with a precision < 10 μm. In fact an accuracy of 1 μ has been obtained on CTF2. Thanks to its flexibility and its simplicity, the system is expected to adapt easily to CLIC even if it means to control modules that involve up to a maximum of 384 motors and 896 sensors

  2. Evaluation of Components for the High Precision Inductive Adder for the CLIC Damping Rings

    CERN Document Server

    Holma, J

    2012-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse generators for the damping ring kickers must provide extremely flat high-voltage pulses. The specifications for the extraction kickers of the CLIC damping rings are particularly demanding: the flattop of the output pulse must be 160 ns duration, 12.5 kV and 250 A, with a combined ripple and droop of not more than ±0.02 %. An inductive adder allows the use of different modulation techniques and is therefore a very promising approach to meeting the specifications. In addition to semiconductors working in their saturated region, semiconductors working in their linear region are needed for applying analogue modulation techniques. Simulat...

  3. The CLIC electron and positron polarized sources

    CERN Document Server

    Rinolfi, Louis; Bulyak, Eugene; Chehab, Robert; Dadoun, Olivier; Gai, Wei; Gladkikh, Peter; Kamitani, Takuya; Kuriki, Masao; Liu, Wanming; Maryuama, Takashi; Omori, Tsunehiko; Poelker, Matt; Sheppard, John; Urakawa, Junji; Variola, Alessandro; Vivoli, Alessandro; Yakimenko, Vitaly; Zhou, Feng; Zimmermann, Frank

    2010-01-01

    The CLIC polarized electron source is based on a DC gun where the photocathode is illuminated by a laser beam. Each micro-bunch has a charge of 6x109 e−, a width of 100 ps and a repetition rate of 2 GHz. A peak current of 10 A in the micro-bunch is a challenge for the surface charge limit of the photo-cathode. Two options are feasible to generate the 2 GHz e− bunch train: 100 ps micro-bunches can be extracted from the photo-cathode either by a 2 GHz laser system or by generating a macro-bunch using a ~200 ns laser pulse and a subsequent RF bunching system to produce the appropriate micro-bunch structure. Recent results obtained by SLAC, for the latter case, are presented. The polarized positron source is based on a positron production scheme in which polarized photons are produced by a laser Compton scattering process. The resulting circularly-polarized gamma photons are sent onto a target, producing pairs of longitudinally polarized electrons and positrons. The Compton backscattering process occurs eithe...

  4. Minimizing Emittance for the CLIC Damping Ring

    CERN Document Server

    Braun, H; Levitchev, E; Piminov, P; Schulte, Daniel; Siniatkin, S; Vobly, P P; Zimmermann, Frank; Zolotarev, Konstantin V; CERN. Geneva

    2006-01-01

    The CLIC damping rings aim at unprecedented small normalized equilibrium emittances of 3.3 nm vertical and 550 nm horizontal, for a bunch charge of 2.6·109 particles and an energy of 2.4 GeV. In this parameter regime the dominant emittance growth mechanism is intra-beam scattering. Intense synchrotron radiation damping from wigglers is required to counteract its effect. Here the overall optimization of the wiggler parameters is described, taking into account state-of-the-art wiggler technologies, wiggler effects on dynamic aperture, and problems of wiggler radiation absorption. Two technical solutions, one based on superconducting magnet technology the other on permanent magnets are presented. Although dynamic aperture and tolerances of this ring design remain challenging, benefits are obtained from the strong damping. For optimized wigglers, only bunches for a single machine pulse may need to be stored, making injection/extraction particularly simple and limiting the synchrotron-radiation power. With a 36...

  5. CLIC/ILC Researchers Explore New Avenues for Collaboration

    CERN Multimedia

    Katarina Anthony

    2010-01-01

    Researchers from CLIC and ILC met for their first common International Workshop on Linear Colliders, which was held in Geneva from 18 to 22 October. Although the talks were mostly scientific and technical, the political message behind them was a breakthrough, as the workshop showed the progress made in unifying the two communities.   The International Workshop on Linear Colliders (IWLC), which was organised by the European Committee for Future Accelerators, hosted by CERN, and held at CERN and the International Conference Centre in Geneva, attracted a large audience of about 500 experts. Although there have been other joint conferences between the CLIC and ILC communities before, they have all been focused on specific technical and/or managerial issues. The IWLC was part of an ongoing effort by CLIC and ILC to provide an environment in which researchers can exchange ideas, inform their peers about their most recent achievements and work together on common issues. Given the possible technical ov...

  6. Status of Wakefield Monitor Experiments at the CLIC Test Facility

    CERN Document Server

    Lillestøl, Reidar; Aftab, Namra; Corsini, Roberto; Döbert, Steffen; Farabolini, Wilfrid; Grudiev, Alexej; Javeed, Sumera; Pfingstner, Juergen; Wuensch, Walter

    2016-01-01

    For the very low emittance beams in CLIC, it is vital to mitigate emittance growth which leads to reduced luminosity in the detectors. One factor that leads to emittance growth is transverse wakefields in the accelerating structures. In order to combat this the structures must be aligned with a precision of a few um. For achieving this tolerance, accelerating structures are equipped with wakefield monitors that measure higher-order dipole modes excited by the beam when offset from the structure axis. We report on such measurements, performed using prototype CLIC accelerating structures which are part of the module installed in the CLIC Test Facility 3 (CTF3) at CERN. Measurements with and without the drive beam that feeds rf power to the structures are compared. Improvements to the experimental setup are discussed, and finally remaining measurements that should be performed before the completion of the program are summarized.

  7. Vertex-Detector R&D for CLIC

    CERN Document Server

    Dannheim, D

    2014-01-01

    A detector concept based on hybrid pixel-detector technology is under development for the CLIC vertex detector. It comprises fast, low-power and small-pitch readout ASICs implemented in 65 nm CMOS technology (CLICpix) coupled to ultra-thin sensors (planar or active HV-CMOS) via low-mass interconnects. The power dissipation of the readout chips is reduced by means of power pulsing, allowing for a cooling system based on forced air flow. In this contribution the CLIC vertex-detector requirements are reviewed and the current status of R&D on readout and sensors is presented.

  8. Beam Loading Compensation in the Main Linac of CLIC

    OpenAIRE

    Schulte, D.; Syratchev, I.

    2000-01-01

    Compensation of multi-bunch beam loading is of great importance in the main linac of the Compact Linear Collider (CLIC). The bunch-to-bunch energy variation has to stay below 1 part in 1000. In CLIC, the RF power is obtained by decelerating a drive beam which is formed by merging a number of short bunch trains. A promising scheme for tackling beam loading in the main linac is based on varying the lengths of the bunch trains in the drive beam. The scheme and its expected performance are presen...

  9. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    Science.gov (United States)

    Tehrani, N. Alipour; Arfaoui, S.; Benoit, M.; Dannheim, D.; Dette, K.; Hynds, D.; Kulis, S.; Perić, I.; Petrič, M.; Redford, S.; Sicking, E.; Valerio, P.

    2016-07-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor, where efficiencies of greater than 99% have been achieved at -60 V substrate bias, with a single hit resolution of 6.1 μm . Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  10. Simulation of Phase Stability at the Flat Top of the CLIC Drive Beam

    CERN Document Server

    Gerbershagen, A; Burrows, P

    2011-01-01

    The drive beam phase stability is one of the critical issues of the Compact Linear Collider (CLIC). In this paper the generation and propagation of drive beam phase errors is studied for effects that vary during the drive beam pulse. This includes the influence of drive beam current and phase errors as well as of drive beam accelerator RF phase and amplitude errors on the drive beam phase after the compressor chicanes and the analysis of the propagation of these errors through the drive beam combination scheme. The impact of the imperfections on the main beam is studied including the possible correction with help of a feedforward system.

  11. Photon-Nucleon Collider based on LHC and CLIC

    CERN Document Server

    Aksakal, Husnu; Schulte, Daniel; Zimmermann, Frank

    2005-01-01

    We describe the scheme of a photon-nucleon collider where high energy photons generated by Compton backscattering off a CLIC electron beam, at either 75 GeV or 1.5 TeV are collided with protons or ions stored in LHC. Different design constraints for such a collider are discussed and achievable luminosity performance is estimated.

  12. Grid Interface Design for the Compact Linear Collider (CLIC)

    CERN Document Server

    Jankovic, Maria; Clare, Jon; Wheeler, Pat; Aguglia, Davide

    2015-01-01

    This paper discusses the grid interface challenges for CERN’s proposed Compact Linear Colliders’ (CLIC) klystron modulators, including a 280 MW power system optimisation. The modular multilevel converter is evaluated as a candidate topology for a Medium Voltage grid interface along with a control method for reducing the impact of klystron modulators on the electrical network.

  13. A Versatile Beam Loss Monitoring System for CLIC

    CERN Document Server

    Kastriotou, Maria; Farabolini, Wilfrid; Holzer, Eva Barbara; Nebot Del Busto, Eduardo; Tecker, Frank; Welsch, Carsten

    2016-01-01

    The design of a potential CLIC beam loss monitoring (BLM) system presents multiple challenges. To successfully cover the 48 km of beamline, ionisation chambers and optical fibre BLMs are under investigation. The former fulfils all CLIC requirements but would need more than 40000 monitors to protect the whole facility. For the latter, the capability of reconstructing the original loss position with a multi-bunch beam pulse and multiple loss locations still needs to be quantified. Two main sources of background for beam loss measurements are identified for CLIC. The two-beam accelerator scheme introduces so-called crosstalk, i.e. detection of losses originating in one beam line by the monitors protecting the other. Moreover, electrons emitted from the inner surface of RF cavities and boosted by the high RF gradients may produce signals in neighbouring BLMs, limiting their ability to detect real beam losses. This contribution presents the results of dedicated experiments performed in the CLIC Test Facility to qu...

  14. Production of excited electrons at TESLA and CLIC based $e\\gamma$ colliders

    CERN Document Server

    Aydin, Z Z; Kirca, Z

    2003-01-01

    We analyze the potential of TESLA and CLIC based electron-photon colliders to search for excited spin-1/2 electrons. The production of excited electrons in the resonance channel through the electron-photon collision and their subsequent decays to leptons and electroweak gauge bosons are investigated. We study in detail the three signal channels of excited electrons and the corresponding backgrounds through the reactions e gamma --> e gamma, e gamma --> eZ and e gamma --> nu W. Excited electrons can be discovered with the masses up to about 90% of the available collider energy.

  15. A Search for Leptophilic Vector Boson Z_l at CLIC by Using Neural Networks

    CERN Document Server

    Akkoyun, S

    2012-01-01

    In this work, the possible dynamics associated with leptophilic Z_l boson at CLIC (Compact Linear Collider) have been investigated by using artificial neural networks (ANNs). These hypotetic massive boson Z_l have been shown through the process e+e- -> M+M-. Furthermore, the invariant mass distributions for final muons have been consistently predicted by using ANN. For these highly non-linear data, we have constructed consistent empirical physical formulas (EPFs) by appropriate feed- forward ANN. These ANN-EPFs can be used to derive further physical functions which could be relevant to studying Z_l.

  16. Anomalous production of top quarks at CLIC+LHC based gamma p colliders

    CERN Document Server

    Cakir, O

    2003-01-01

    The single production of top quark due to flavor changing neutral current (FCNC) interaction and its decay to bW are studied at CLIC+LHC based gamma-p colliders. We consider both t-c-gamma and t-u-gamma anomalous couplings. The anomalous charm (up) quark anomalous coupling parameter kappa_gamma^c (kappa_gamma^u) can be probed down to 9.5x10^-3 (8.0x10^-3) at a gamma-p collider with sqrt{s_ep}=6.48 TeV and L_int=100 fb^-1.

  17. X-Band Crab Cavities for the CLIC Beam Delivery System

    International Nuclear Information System (INIS)

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to minimise beam loading and mode separation. The position of the crab cavity close to the final focus enhances the effect of transverse wake-fields so effective wake-field damping is required. A damped detuned structure is proposed to suppress and de-cohere the wake-field hence reducing their effect. Design considerations for the CLIC crab cavity will be discussed as well as the proposed high power testing of these structures at SLAC. Design of a crab cavity for CLIC is underway at the Cockcroft Institute in collaboration with SLAC. This effort draws on a large degree of synergy with the ILC crab cavity developed at the Cockcroft Institute and other deflecting structure development at SLAC. A study of phase and amplitude variations in the cavity suggests that the tolerances are very tight and require a 'beyond state of the art' LLRF control system. A study of cavity geometry and its effect on the cavity fields has been performed using Microwave studio. This study has suggested that for our cavity an iris radius between 4-5 mm is optimum with an iris thickness of 2-3 mm based on group velocity and peak fields. A study of the cavity wakefields show that the single bunch wakes are unlikely to be a problem but the short bunch spacing may cause the multi-bunch wakefields to be an issue. This will require some of the modes to be damped strongly so that the wake is damped significantly before any following bunch arrives. Various methods of damping have been investigated and suggest that

  18. X-Band Crab Cavities for the CLIC Beam Delivery System

    Energy Technology Data Exchange (ETDEWEB)

    Burt, G.; Ambattu, P.K.; Dexter, A.C.; Abram, T.; /Cockcroft Inst. Accel. Sci. Tech. /Lancaster U.; Dolgashev, V.; Tantawi, S.; /SLAC; Jones, R.M.; /Cockcroft Inst. Accel. Sci. Tech. /Manchester U.

    2011-11-22

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to minimise beam loading and mode separation. The position of the crab cavity close to the final focus enhances the effect of transverse wake-fields so effective wake-field damping is required. A damped detuned structure is proposed to suppress and de-cohere the wake-field hence reducing their effect. Design considerations for the CLIC crab cavity will be discussed as well as the proposed high power testing of these structures at SLAC. Design of a crab cavity for CLIC is underway at the Cockcroft Institute in collaboration with SLAC. This effort draws on a large degree of synergy with the ILC crab cavity developed at the Cockcroft Institute and other deflecting structure development at SLAC. A study of phase and amplitude variations in the cavity suggests that the tolerances are very tight and require a 'beyond state of the art' LLRF control system. A study of cavity geometry and its effect on the cavity fields has been performed using Microwave studio. This study has suggested that for our cavity an iris radius between 4-5 mm is optimum with an iris thickness of 2-3 mm based on group velocity and peak fields. A study of the cavity wakefields show that the single bunch wakes are unlikely to be a problem but the short bunch spacing may cause the multi-bunch wakefields to be an issue. This will require some of the modes to be damped strongly so that the wake is damped significantly before any following bunch arrives. Various methods of damping have been investigated and

  19. Z′ Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    OpenAIRE

    A. Gutiérrez-Rodríguez; Hernández-Ruíz, M. A.

    2015-01-01

    We study the prospects of the B-L model with an additional $Z'$ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process $e^{+}e^{-}\\rightarrow (Z, Z') \\to Zh$, including both the resonant and non-resonant effects. We evaluate the total cross section of $Zh$ and we calculate the total number of events for integrated luminosities of 500-2000\\hspace{0.8mm}$fb^{-1}$ and center of mass en...

  20. Design of the 15 GHz BPM test bench for the CLIC test facility to perform precise stretchedwire RF measurements

    CERN Document Server

    Silvia Zorzetti, Silvia; Galindo Muño, Natalia; Wendt, Manfred

    2015-01-01

    The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-m regime is required. Within the PACMAN3 (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) PhD training action a study with the objective of pre-aligning the electrical centre of a 15 GHz cavity beam position monitor (BPM) to the magnetic centre of the main beam quadrupole is initiated. Of particular importance is the design of a specific test bench to study the stretched-wire setup for the CLIC Test Facility (CTF3) BPM, focusing on the aspects of microwave signal excitation, transmission and impedance-matching, as well as the mechanical setup and reproducibility of the measurement method.

  1. CLIC-ACM: generic modular rad-hard data acquisition system based on CERN GBT versatile link

    International Nuclear Information System (INIS)

    CLIC is a world-wide collaboration to study the next ''terascale'' lepton collider, relying upon a very innovative concept of two-beam-acceleration. This accelerator, currently under study, will be composed of the subsequence of 21000 two-beam-modules. Each module requires more than 300 analogue and digital signals which need to be acquired and controlled in a synchronous way. CLIC-ACM (Acquisition and Control Module) is the 'generic' control and acquisition module developed to accommodate the controls of all these signals for various sub-systems and related specification in term of data bandwidth, triggering and timing synchronization. This paper describes the system architecture with respect to its radiation-tolerance, power consumption and scalability

  2. Interaction of the chloride intracellular ion channel protein CLIC1 with different sterols in model membranes

    International Nuclear Information System (INIS)

    Background and Aims: Sterols have been reported to modulate conformation and hence the function of several membrane proteins. One such group is the Chloride Intracellular Ion Channel (CLIC) family of proteins. The CLIC protein family consists of six evolutionarily conserved protein members in vertebrates. These proteins are unusual, existing as both monomeric soluble proteins and as membrane bound proteins. We now for the first time demonstrate that the spontaneous membrane insertion of CLIC1 is dependent on the presence of cholesterol in membranes. Our novel findings also extend to the identification of a cholesterol-binding domain within CLIC1 that facilitates the spontaneous membrane insertion of the protein into membranes containing cholesterol. Methods: CLIC1 wild type (WT) and mutant proteins were purified by Ni-NTA followed by size‐exclusion chromatography. Langmuir monolayer film balance experiments were carried out using 1-Palmitoyl-2-oleoylphosphatidylcholine (POPC) alone, or in a 5:1 mole ratio combination with either one of the following sterols: Cholesterol (CHOL), β-Sitosterol (SITO), Ergosterol (ERG), Hydroxyecdysone (HYD) or Cholestane (CHOS). WT CLIC1 or mutant versions of CLIC1 were then injected into the aqueous subphase under the lipid film. Results: In lipid monolayers lacking sterols, CLIC1 did not insert. However significant membrane insertion occurred when CLIC1 was added to membranes containing cholesterol. Substitution of membrane cholesterol with either HYD, SITO or ERG, not only increased CLIC1’s membrane interaction but also increased its rate of insertion. Conversely, CLIC1 showed no insertion into monolayers containing CHOS, which lacked the intact sterol 3β-OH group. CLIC1 mutants G18A and G22A, did not insert in POPC:CHOL monolayers whereas the C24A mutant showed membrane insertion equivalent to WT CLIC1. X-ray and Neutron reflectivity, along with Small Angle X-ray Scattering techniques were subsequently used to probe

  3. A CLIC Damping Wiggler Prototype at ANKA: Commissioning and Preparations for a Beam Dynamics Experimental Program

    CERN Document Server

    Bernhard, Axel; Casalbuoni, Sara; Ferracin, Paolo; Garcia Fajardo, Laura; Gerstl, Stefan; Gethmann, Julian; Grau, Andreas; Huttel, Erhard; Khrushchev, Sergey; Mezentsev, Nikolai; Müller, Anke-Susanne; Papaphilippou, Yannis; Saez de Jauregui, David; Schmickler, Hermann; Schoerling, Daniel; Shkaruba, Vitaliy; Smale, Nigel; Tsukanov, Valery; Zisopoulos, Panagiotis; Zolotarev, Konstantin

    2016-01-01

    In a collaboration between CERN, BINP and KIT a prototype of a superconducting damping wiggler for the CLIC damping rings has been installed at the ANKA synchrotron light source. On the one hand, the foreseen experimental program aims at validating the technical design of the wiggler, particularly the conduction cooling concept applied in its cryostat design, in a long-term study. On the other hand, the wiggler's influence on the beam dynamics particularly in the presence of collective effects is planned to be investigated. ANKA's low-alpha short-bunch operation mode will serve as a model system for these studies on collective effects. To simulate these effects and to make verifiable predictions an accurate model of the ANKA storage ring in low-alpha mode, including the insertion devices is under parallel development. This contribution reports on the first operational experience with the CLIC damping wiggler prototype in the ANKA storage ring and steps towards the planned advanced experimental program with th...

  4. Common ground in ILC and CLIC detector concepts

    CERN Multimedia

    Daisy Yuhas

    2013-01-01

    The Compact Linear Collider and the International Linear Collider will accelerate particles and create collisions in different ways. Nonetheless, the detector concepts under development share many commonalities.   Timepix chips under scrutiny in the DESY test beam with the help of the beam telescope. CERN physicist Dominik Dannheim explains that the CLIC detector plans are adaptations of the ILC detector designs with a few select modifications. “When we started several years ago, we did not want to reinvent the wheel,” says Dannheim. “The approved ILC detector concepts served as an excellent starting point for our designs.” Essential differences Both CLIC and ILC scientists foresee general-purpose detectors that make measurements with exquisite precision. These colliders, however, have very different operating parameters, which will have important consequences for the various detector components. The ILC’s collision energy is set at 500 GeV ...

  5. Intra-Beam scattering in the CLIC Damping Rings

    CERN Document Server

    Vivoli, A

    2010-01-01

    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 a lattice of the CLIC damping rings.

  6. Assembly Test of Elastic Averaging Technique to Improve Mechanical Alignment for Accelerating Structure Assemblies in CLIC

    CERN Document Server

    Huopana, J

    2010-01-01

    The CLIC (Compact LInear Collider) is being studied at CERN as a potential multi-TeV e+e- collider [1]. The manufacturing and assembly tolerances for the required RF-components are important for the final efficiency and for the operation of CLIC. The proper function of an accelerating structure is very sensitive to errors in shape and location of the accelerating cavity. This causes considerable issues in the field of mechanical design and manufacturing. Currently the design of the accelerating structures is a disk design. Alternatively it is possible to create the accelerating assembly from quadrants, which favour the mass manufacturing. The functional shape inside of the accelerating structure remains the same and a single assembly uses less parts. The alignment of these quadrants has been previously made kinematic by using steel pins or spheres to align the pieces together. This method proved to be a quite tedious and time consuming method of assembly. To limit the number of different error sources, a meth...

  7. Initial measurements on a prototype inductive adder for the CLIC kicker systems

    CERN Document Server

    Holma, Janne

    2013-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the damping ring kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the extraction kickers of the DRs are particularly demanding: the flattops of the pulses must be ±12.5 kV with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications. To achieve ultra-flat pulses with a fast rise time the output impedance of the inductive adder needs to be well matched to the system impedance. The parasitic circuit elements of the inductive adder have a significant effect upon the output impedance and these values are very difficult to calculate accurately analytically. To predict these paramet...

  8. Modelling of Parasitic Inductances of a High Precision Inductive Adder for CLIC

    CERN Document Server

    Holma, J; Ovaska, S J

    2013-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the damping ring kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the extraction kickers of the DRs are particularly demanding: the flat-top of the pulses must be ±12.5 kV with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications. However, the output impedance of the inductive adder needs to be well matched to the system impedance. The primary leakage inductance, which cannot be computed accurately analytically, has a significant effect upon the output impedance of the inductive adder. This paper presents predictions, obtained by modelling the 3D geometry of the adder struc...

  9. Integration of the PHIN RF Gun into the CLIC Test Facility

    CERN Document Server

    Döbert, Steffen

    2006-01-01

    CERN is a collaborator within the European PHIN project, a joint research activity for Photo injectors within the CARE program. A deliverable of this project is an rf Gun equipped with high quantum efficiency Cs2Te cathodes and a laser to produce the nominal beam for the CLIC Test Facility (CTF3). The nominal beam for CTF3 has an average current of 3.5 A, 1.5 GHz bunch repetition frequency and a pulse length of 1.5 ìs (2332 bunches) with quite tight stability requirements. In addition a phase shift of 180 deg is needed after each train of 140 ns for the special CLIC combination scheme. This rf Gun will be tested at CERN in fall 2006 and shall be integrated as a new injector into the CTF3 linac, replacing the existing injector consisting of a thermionic gun and a subharmonic bunching system. The paper studies the optimal integration into the machine trying to optimize transverse and longitudinal phase space of the beam while respecting the numerous constraints of the existing accelerator. The presented scheme...

  10. Measurements on Prototype Inductive Adders with Ultra-Flat-Top Output Pulses for CLIC DR Kickers

    CERN Document Server

    Holma, J; Belver-Aguilar, C

    2014-01-01

    The CLIC study is investigating the technical feasibility of an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings (DRs) will produce ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the DR kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the DR extraction kickers call for a 160 ns duration flat-top pulses of ±12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications because this topology allows the use of both passive and analogue modulation methods to adjust the output waveform. Recently, two five-layer, 3.5 kV, prototype inductive adders have been built at CERN. The first of these has been used to test the passive and active analogue modulation methods to compensate voltage droop and ripple of the output pulses. Pulse waveforms have been reco...

  11. CLIC a Two-Beam Multi-TeV $e\\pm$ Linear Collider

    CERN Document Server

    Delahaye, J P; Assmann, R W; Becker, F; Bossart, Rudolf; Braun, H; Burkhardt, H; Carron, G; Coosemans, Williame; Corsini, R; D'Amico, T E; Döbert, Steffen; Fartoukh, Stéphane David; Ferrari, A; Geschonke, Günther; Godot, J C; Groening, L; Guignard, Gilbert; Hutchins, S; Jeanneret, J B; Jensen, E; Jowett, John M; Kamitani, T; Millich, Antonio; Pearce, P; Perriollat, F; Pittin, R; Potier, J P; Riche, A; Rinolfi, Louis; Risselada, Thys; Royer, P; Ruggiero, F; Schulte, Daniel; Suberlucq, Guy; Syratchev, I V; Thorndahl, L; Trautner, H; Verdier, A; Wuensch, Walter; Zhou, F; Zimmermann, Frank; Napoly, O

    2000-01-01

    The CLIC study of a high-energy (0.5 - 5 TeV), high-luminosity (1034 - 1035 cm-2 sec-1) e± linear collider is presented. Beam acceleration using high frequency (30 GHz) normal-conducting structures operating at high accelerating fields (150 MV/m) significantly reduces the length and, in consequence, the cost of the linac. Using parameters derived from general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. A new cost-effective and efficient drive beam generation scheme for RF power production by the so-called "Two-Beam Acceleration" method is described. It uses a thermionic gun and a fully-loaded normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches, and RF multiplication by funnelling in compressor rings to produce the desired bunch structure. Recent 30 GHz hardware developments and CLIC Test Facility (CTF) results are described.

  12. Online Resources for High School Teachers--A CLIC Away

    Science.gov (United States)

    Holmes, Jon L.

    2000-04-01

    "I'm a high school teacher. I don't have time to sift through all of JCE to find what I need. I don't have enough time as it is!" If you need to find things in a hurry, go to JCE HS CLIC, the JCE High School Chemed Learning Information Center, http://JChemEd.chem.wisc.edu/HS/. You will find good solid, reliable information, and you will find it fast. CLIC is open 24 hours every day, all over the world. What You Will Find at JCE CLIC We know teachers are pressed for time. During the few minutes between classes or at the end of the day, information needs to be found very quickly. Perhaps you are looking for a demo that illustrates electrochemistry using Cu, Mg, orange juice, and a clock; or a student activity on chromatography that is ready to copy and hand out; or a video to illustrate the action of aqua regia on gold, because you can't use aqua regia and can't afford gold. You can find each of these quickly at CLIC. The Journal has always provided lots of articles designed with high school teachers in mind. What the new JCE HS CLIC does is collect the recent materials at one address on JCE Online, making it quicker and easier for you to find them. Information has been gathered from both print and online versions of the Journal, from JCE Software, and from JCE Internet. It is organized as shown at the bottom of the page. Getting Access to Information You have located something that interests you, perhaps a list of tested demonstrations that pertain to consumer chemistry. Now it is time to get it. JCE subscribers (individuals and libraries) can read, download, and print the full versions of the articles as well as all supplemental materials, including student handouts and instructor's notes. You will need the username and password that are on the mailing label that comes with your Journaleach month. JCE HS CLIC home page: http://JChemEd.chem.wisc.edu/HS/ Your Suggestions, Please Our plans for JCE HS CLIC do not end with what you find now. Other resources and features

  13. Interaction Point Backgrounds from the CLIC Post Collision Line

    OpenAIRE

    Salt, Michael David

    2012-01-01

    The proposed CLIC accelerator is designed to collide electrons and positrons ata centre of mass energy of 3 TeV, and a luminosity of 5.9 x 10^(34) cm^(−2) s^(−1) at the interactionpoint (IP). Being a single-pass machine, luminosity must be maximised byminimising the beam spot size to the order of a few nanometres. The effects of the finalfocussing and the intense beam-beam effects lead to a high production cross sectionof beamstrahlung photons, and highly divergent outgoing beams, both spatia...

  14. A prototype hybrid pixel detector ASIC for the CLIC experiment

    CERN Document Server

    Valerio, P; Arfaoui, S; Ballabriga, R; Benoit, M; Bonacini, S; Campbell, M; Dannheim, D; De Gaspari, M; Felici, D; Kulis, S; Llopart, X; Nascetti, A; Poikela, T; Wong, W S

    2014-01-01

    A prototype hybrid pixel detector ASIC specifically designed to the requirements of the vertex detector for CLIC is described and first electrical measurements are presented. The chip has been designed using a commercial 65 nm CMOS technology and comprises a matrix of 64x64 square pixels with 25 μm pitch. The main features include simultaneous 4-bit measure- ment of Time-over-Threshold (ToT) and Time-of-Arrival (ToA) with 10 ns accuracy, on-chip data compression and power pulsing capability.

  15. An Asset Test of the CLIC Accelerating Structure

    International Nuclear Information System (INIS)

    Transverse wakefield suppression in the CLIC (Compact Linear Collider) multibunch accelerating structure, called the TDS (Tapered Damped Structure), is achieved primarily through heavy damping. In order to verify the performance of the TDS design and the validity of the theoretical tools used to model it, a 15 GHz version of the TDS has been constructed and tested in the ASSET facility at SLAC. The test has directly demonstrated transverse wakefield suppression of over a factor 100, with an excellent agreement between the measured and the calculated wakefield

  16. Results from the CLIC X-BAND structure test program at the NLCTA

    CERN Document Server

    Adolphsen, Chris; Dolgashev, Valery; Laurent, Lisa; Tantawi, Sami; Wang, Faya; Wang, W Juwen; Doebert, Steffen; Grudiev, Alexej; Riddone, Germana; Wuensh, Walter; Zennaro, Riccardo; Higashi, Yasuo; Higo, Toshiyasu

    2010-01-01

    As part of a SLAC-CERN-KEK col­lab­o­ra­tion on high gra­di­ent X-band struc­ture re­search, sev­er­al pro­to­type struc­tures for the CLIC lin­ear col­lid­er study have been test­ed using two of the high power (300 MW) X-band rf sta­tions in the NLCTA fa­cil­i­ty at SLAC. These struc­tures dif­fer in terms of their man­u­fac­tur­ing (brazed disks and clamped quad­rants), gra­di­ent pro­file (amount by which the gra­di­ent in­creas­es along the struc­ture which op­ti­mizes ef­fi­cien­cy and max­i­mizes sus­tain­able gra­di­ent) and HOM damp­ing (use of slots or waveg­uides to rapid­ly dis­si­pate dipole mode en­er­gy). The CLIC goal in the next few years is to demon­strate the fea­si­bil­i­ty of a CLIC-ready base­line de­sign and to in­ves­ti­gate al­ter­na­tives which could bring even high­er ef­fi­cien­cy. This paper sum­ma­rizes the high gra­di­ent test re­sults from the NLCTA in sup­port of this ef­fort.

  17. Measurements and Laboratory Tests on a Prototype Stripline Kicker for the CLIC Damping Rings

    CERN Document Server

    Belver-Aguilar, C; Toral, F; Barnes, MJ; Day, H

    2014-01-01

    The Pre-Damping Rings (PDRs) and Damping Rings (DRs) of CLIC are required to reduce the beam emittances to the small values required for the main linacs. The injection and extraction, from the PDRs and DRs, are performed by kicker systems. To achieve both low beam coupling impedance and reasonable broadband impedancematching to the electrical circuit, striplines have been chosen for the kicker elements. Prototype striplines have been built: tests and measurements of these striplines have started. The goal of these tests is to characterize, without beam, the electromagnetic response of the striplines. The tests have been carried out at CERN. To study the signal transmission through the striplines, the measured S-parameters have been compared with simulations. In addition, measurements of longitudinal beam coupling impedance, using the coaxial wire method, are reported and compared with simulations.

  18. High-Gradient test results from a CLIC prototype accelerating structure : TD26CC

    CERN Document Server

    Degiovanni, A; Farabolini, W; Grudiev, A; Kovermann, J; Montessinos, E; Riddone, G; Syratchev, I; Wegner, R; Wuensch, W; Solodko, A; Woolley, B

    2014-01-01

    The CLIC study has progressively tested prototype accelerating structures which incorporate an ever increasing number of features which are needed for a final version ready to be installed in a linear collider. The most recent high power test made in the CERN X-band test stand, Xbox-1, is of a CERN-built prototype which includes damping features but also compact input and output power couplers, which maximize the overall length to active gradient ratio of the structure. The structure’s high-gradient performance, 105 MV/m at 250 ns pulse length and low breakdown rate, matches previously tested structures validating both CERN fabrication and the compact coupler design.

  19. Beam dynamic simulation and optimization of the CLIC positron source and the capture linac

    Science.gov (United States)

    Bayar, C.; Doebert, S.; Ciftci, A. K.

    2016-03-01

    The CLIC Positron Source is based on the hybrid target composed of a crystal and an amorphous target. Simulations have been performed from the exit of the amorphous target to the end of pre-injector linac which captures and accelerates the positrons to an energy of 200 MeV. Simulations are performed by the particle tracking code PARMELA. The magnetic field of the AMD is represented in PARMELA by simple coils. Two modes are applied in this study. The first one is accelerating mode based on acceleration after the AMD. The second one is decelerating mode based on deceleration in the first accelerating structure. It is shown that the decelerating mode gives a higher yield for the e+ beam in the end of the Pre-Injector Linac.

  20. Z′ Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    International Nuclear Information System (INIS)

    We study the prospects of the B-L model with an additional Z′ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process e+e-→(Z,Z′)→Zh, including both the resonant and the nonresonant effects. We evaluate the total cross section of Zh and we calculate the total number of events for integrated luminosities of 500–2000 fb−1 and center of mass energies between 500 and 3000 GeV. We find that the total number of expected Zh events can reach 106, which is a very optimistic scenario and it would be possible to perform precision measurements for both Z′ and Higgs boson in future high-energy e+e- colliders experiments

  1. Z′ Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    Directory of Open Access Journals (Sweden)

    A. Gutiérrez-Rodríguez

    2015-01-01

    Full Text Available We study the prospects of the B-L model with an additional Z′ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process e+e-→(Z,Z′→Zh, including both the resonant and the nonresonant effects. We evaluate the total cross section of Zh and we calculate the total number of events for integrated luminosities of 500–2000 fb−1 and center of mass energies between 500 and 3000 GeV. We find that the total number of expected Zh events can reach 106, which is a very optimistic scenario and it would be possible to perform precision measurements for both Z′ and Higgs boson in future high-energy e+e- colliders experiments.

  2. A closer look at the beam-beam processes at ILC and CLIC

    CERN Document Server

    Hartin, Anthony

    2012-01-01

    The strength of the electromagnetic fields in the bunch collision at a linear collider will have a significant effect, yielding large numbers of beamstrahlung photons and associated coherent pair production. These effects are limited in the proposed ILC beam parameters which limit the strength of the bunch field to $\\Upsilon_{\\text{ave}}=0.27$. The CLIC 3 Tev design by comparison has a $\\Upsilon_{\\text{ave}}=3.34$ yielding huge number of coherent pairs. In terms of the precision physics programs of these proposed colliders there is an imperative to investigate the effect of the strong bunch fields on higher order processes. From the exact wavefunctions used in the calculation of transition rates within the Furry interaction picture, and using appropriate simplifications, a multiplicative factor to the coupling constants was obtained. This indicates a significant variation to the transition rate near threshold energies. Further studies are in progress to calculate the exact effect on expected observables.

  3. R&D for the Vertexing at CLIC

    CERN Document Server

    Redford, S

    2015-01-01

    The Compact Linear Collider is a candidate to be the next high-energy particle physics collider. Using a novel acceleration technique, electrons and positrons would be brought into collision with a centre-of-mass energy of up to 3 TeV. Despite challenging levels of beam-induced background, this would provide a relatively clean environment in which to perform precision physics measurements. The vertex detector would be crucial in achieving this, and would need to provide accurate particle tracking information to facilitate secondary vertex reconstruction and jet flavour-tagging. With this goal in mind, current technological limits are being stretched to design a low occupancy, low mass and low-power dissipation vertex detector for CLIC. A concept comprising thin hybrid pixel detectors coupled to high- performance readout ASICs, power-pulsing and air-flow cooling is under development. In this paper, the CLIC vertex detector requirements are reviewed and the current status of R&D on sensors, readout, powerin...

  4. The CLIC positron source based on compton schemes

    CERN Document Server

    Rinolfi, L; Braun, H; Papaphilippou, Y; Schulte, D; Vivoli, A; Zimmermann, F; Dadoun, O; Lepercq, P; Roux, R; Variola, A; Zomer, F; Pogorelski, I; Yakimenko, V; Gai, W; Liu, W; Kamitani, T; Omori, T; Urakawa, J; Kuriki, M; Takahasi, TM; Bulyak, E; Gladkikh, P; Chehab, R; Clarke, J

    2010-01-01

    The CLIC polarized positron source is based on a positron production scheme in which polarized photons are produced by a Compton process. In one option, Compton backscattering takes place in a so-called “Compton ring”, where an electron beam of 1 GeV interacts with circularly-polarized photons in an optical resonator. The resulting circularly-polarized gamma photons are sent on to an amorphous target, producing pairs of longitudinally polarized electrons and positrons. The nominal CLIC bunch population is 4.2x109 particles per bunch at the exit of the Pre-Damping Ring (PDR). Since the photon flux coming out from a "Compton ring" is not sufficient to obtain the requested charge, a stacking process is required in the PDR. Another option is to use a Compton Energy Recovery Linac (ERL) where a quasicontinual stacking in the PDR could be achieved. A third option is to use a "Compton Linac" which would not require stacking. We describe the overall scheme as well as advantages and constraints of the three option...

  5. Achievements and Future Plans of CLIC Test Facilities

    CERN Document Server

    Braun, Hans Heinrich

    2001-01-01

    CTF2 was originally designed to demonstrate the feasibility of two-beam acceleration with high current drive beams and a string of 30 GHz CLIC accelerating structure prototypes (CAS). This goal was achieved in 1999 and the facility has since been modified to focus on high gradient testing of CAS's and 30 GHz single cell cavities (SCC). With these modifications, it is now possible to provide 30 GHz RF pulses of more than 150 MW and an adjustable pulselength from 3 to 15 ns. While the SCC results are promising, the testing of CAS's revealed problems of RF breakdown and related surface damage. As a consequence, a new R&D program has been launched to advance the understanding of RF breakdown processes, to improve surface properties, investigate new materials and to optimise the structure geometries of the CAS's. In parallel the construction of a new facility named CTF3 has started. CTF3 will mainly serve two purposes. The first is the demonstration of the CLIC drive beam generation scheme. CTF3 will acceler-a...

  6. Ground Motion Mitigation in the Main Linac of CLIC

    International Nuclear Information System (INIS)

    Full text: The future linear collider CLIC (Compact Linear Collider) is CERN's propose for a successor of the LHC (Large Hadron Collider). The design of CLIC requires ultralow particle beam emittances, which makes the accelerator very sensitive to ground motion. Without countermeasure, the beam quality would be already unacceptable after a few seconds. In our work we present a feedback algorithm, which mitigates the parasitic effects of ground motion in the main linac of CLIC efficiently. We use an adaptive controller, which is composed of two parts: a system identification unit and a SVD control algorithm. The system identification unit calculates on-line estimates of the time changing accelerator behaviour. This precise model, which can adapt to system changes, is used by the control algorithm. If the system identification unit would not be used, drifting accelerator parameter would cause a mismatch between the real accelerator behaviour and the model used by the controller, which would result in a poor controller performance. Standard system identification algorithms cannot be used in an accelerator environment. The indispensable system excitation cause a not tolerable emittance growth, if it is applied thoughtless. Instead a special excitation scheme consisting of interleaved beam bumps was implemented, which keeps the emittance growth at an acceptable level. However, this special excitation has the disadvantage that not the complete system can be identified anymore. To still get an all over model of the system, we use the identification data and interpolate them with the help of a beam oscillation amplitude model, derived for the main linac of CLIC. The control algorithm uses the identified system data, which are the orbit response matrix R. With the help of the SVD decomposition of R, a very efficient filter can be created. This filter reconstructs the ground motion components, which are causing the majority of the emittance growth. At the same time the

  7. Design of the 15 GHz BPM test bench for the CLIC test facility to perform precise stretched-wire RF measurements

    Science.gov (United States)

    Zorzetti, Silvia; Fanucci, Luca; Galindo Muñoz, Natalia; Wendt, Manfred

    2015-09-01

    The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-μm regime is required. Within the PACMAN3 (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) PhD training action a study with the objective of pre-aligning the electrical centre of a 15 GHz cavity beam position monitor (BPM) to the magnetic centre of the main beam quadrupole is initiated. Of particular importance is the design of a specific test bench to study the stretched-wire setup for the CLIC Test Facility (CTF3) BPM, focusing on the aspects of microwave signal excitation, transmission and impedance-matching, as well as the mechanical setup and reproducibility of the measurement method.

  8. Design of the 15 GHz BPM test bench for the CLIC test facility to perform precise stretched-wire RF measurements

    International Nuclear Information System (INIS)

    The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-μm regime is required. Within the PACMAN3 (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) PhD training action a study with the objective of pre-aligning the electrical centre of a 15 GHz cavity beam position monitor (BPM) to the magnetic centre of the main beam quadrupole is initiated. Of particular importance is the design of a specific test bench to study the stretched-wire setup for the CLIC Test Facility (CTF3) BPM, focusing on the aspects of microwave signal excitation, transmission and impedance-matching, as well as the mechanical setup and reproducibility of the measurement method. (paper)

  9. CLIC crab cavity design optimisation for maximum luminosity

    International Nuclear Information System (INIS)

    The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

  10. CLIC Crab Cavity Design Optimisation for Maximum Luminosity

    Energy Technology Data Exchange (ETDEWEB)

    Dexter, A.C.; /Lancaster U. /Cockcroft Inst. Accel. Sci. Tech.; Burt, G.; /Lancaster U. /Cockcroft Inst. Accel. Sci. Tech.; Ambattu, P.K.; /Lancaster U. /Cockcroft Inst. Accel. Sci. Tech.; Dolgashev, V.; /SLAC; Jones, R.; /Manchester U.

    2012-04-25

    The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

  11. CLIC crab cavity design optimisation for maximum luminosity

    Energy Technology Data Exchange (ETDEWEB)

    Dexter, A.C., E-mail: a.dexter@lancaster.ac.uk [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Burt, G.; Ambattu, P.K. [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Dolgashev, V. [SLAC, Menlo Park, CA 94025 (United States); Jones, R. [University of Manchester, Manchester, M13 9PL (United Kingdom)

    2011-11-21

    The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

  12. Vacuum arc localization in CLIC prototype radio frequency accelerating structures

    CERN Document Server

    AUTHOR|(CDS)2091976; Koivunen, Visa

    2016-04-04

    A future linear collider capable of reaching TeV collision energies should support accelerating gradients beyond 100 MV/m. At such high fields, the occurrence of vacuum arcs have to be mitigated through conditioning, during which an accelerating structure’s resilience against breakdowns is slowly increased through repeated radio frequency pulsing. Conditioning is very time and resource consuming, which is why developing more efficient procedures is desirable. At CERN, conditioning related research is conducted at the CLIC high-power X-band test stands. Breakdown localization is an important diagnostic tool of accelerating structure tests. Abnormal position distributions highlight issues in structure design, manufacturing or operation and may consequently help improve these processes. Additionally, positioning can provide insight into the physics of vacuum arcs. In this work, two established positioning methods based on the time-difference-ofarrival of radio frequency waves are extended. The first method i...

  13. Cholesterol Promotes Interaction of the Protein CLIC1 with Phospholipid Monolayers at the Air–Water Interface

    Directory of Open Access Journals (Sweden)

    Khondker R. Hossain

    2016-02-01

    Full Text Available CLIC1 is a Chloride Intracellular Ion Channel protein that exists either in a soluble state in the cytoplasm or as a membrane bound protein. Members of the CLIC family are largely soluble proteins that possess the intriguing property of spontaneous insertion into phospholipid bilayers to form integral membrane ion channels. The regulatory role of cholesterol in the ion-channel activity of CLIC1 in tethered lipid bilayers was previously assessed using impedance spectroscopy. Here we extend this investigation by evaluating the influence of cholesterol on the spontaneous membrane insertion of CLIC1 into Langmuir film monolayers prepared using 1-palmitoyl-2-oleoylphosphatidylcholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-ethanolamine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine alone or in combination with cholesterol. The spontaneous membrane insertion of CLIC1 was shown to be dependent on the presence of cholesterol in the membrane. Furthermore, pre-incubation of CLIC1 with cholesterol prior to its addition to the Langmuir film, showed no membrane insertion even in monolayers containing cholesterol, suggesting the formation of a CLIC1-cholesterol pre-complex. Our results therefore suggest that CLIC1 membrane interaction involves CLIC1 binding to cholesterol located in the membrane for its initial docking followed by insertion. Subsequent structural rearrangements of the protein would likely also be required along with oligomerisation to form functional ion channels.

  14. Cholesterol Promotes Interaction of the Protein CLIC1 with Phospholipid Monolayers at the Air–Water Interface

    Science.gov (United States)

    Hossain, Khondker R.; Al Khamici, Heba; Holt, Stephen A.; Valenzuela, Stella M.

    2016-01-01

    CLIC1 is a Chloride Intracellular Ion Channel protein that exists either in a soluble state in the cytoplasm or as a membrane bound protein. Members of the CLIC family are largely soluble proteins that possess the intriguing property of spontaneous insertion into phospholipid bilayers to form integral membrane ion channels. The regulatory role of cholesterol in the ion-channel activity of CLIC1 in tethered lipid bilayers was previously assessed using impedance spectroscopy. Here we extend this investigation by evaluating the influence of cholesterol on the spontaneous membrane insertion of CLIC1 into Langmuir film monolayers prepared using 1-palmitoyl-2-oleoylphosphatidylcholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-ethanolamine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine alone or in combination with cholesterol. The spontaneous membrane insertion of CLIC1 was shown to be dependent on the presence of cholesterol in the membrane. Furthermore, pre-incubation of CLIC1 with cholesterol prior to its addition to the Langmuir film, showed no membrane insertion even in monolayers containing cholesterol, suggesting the formation of a CLIC1-cholesterol pre-complex. Our results therefore suggest that CLIC1 membrane interaction involves CLIC1 binding to cholesterol located in the membrane for its initial docking followed by insertion. Subsequent structural rearrangements of the protein would likely also be required along with oligomerisation to form functional ion channels. PMID:26875987

  15. Design of the CLIC Quadrupole Vacuum Chambers

    CERN Document Server

    Garion, C

    2010-01-01

    The Compact Linear Collider, under study, requires vacuum chambers with a very small aperture, of the order of 8 mm in diameter, and with a length up to around 2 m for the main beam quadrupoles. To keep the very tight geometrical tolerances on the quadrupoles, no bake out is allowed. The main issue is to reach UHV conditions (typically 10-9 mbar static pressure) in a system where the vacuum performance is driven by water outgassing. For this application, a thinwalled stainless steel vacuum chamber with two ante chambers equipped with NEG strips, is proposed. The mechanical design, especially the stability analysis, is shown. The key technologies of the prototype fabrication are given. Vacuum tests are carried out on the prototypes. The test set-up as well as the pumping system conditions are presented.

  16. Development of Stripline Kickers for Low Emittance Rings: Application to the Beam Extraction Kicker for CLIC Damping Rings

    CERN Document Server

    AUTHOR|(SzGeCERN)728476; Toral Fernandez, Fernando

    In the framework of the design study of Future Linear Colliders, the Compact Linear Collider (CLIC) aims for electron-positron collisions with high luminosity at a nominal centre-of-mass energy of 3 TeV. To achieve the luminosity requirements, Pre-Damping Rings (PDRs) and Damping Rings (DRs) are required: they reduce the beam emittance before the beam is accelerated in the main linac. Several injection and extraction systems are needed to inject and extract the beam from the PDRs and DRs. The work of this Thesis consists of the design, fabrication and laboratory tests of the first stripline kicker prototype for beam extraction from the CLIC DRs, although the methodology proposed can be extended to stripline kickers for any low emittance ring. The excellent field homogeneity required, as well as a good transmission of the high voltage pulse through the electrodes, has been achieved by choosing a novel electrode shape. With this new geometry, it has been possible to benefit from all the advantages that the most...

  17. A New Technique For Information Processing of CLIC Technical Documentation

    CERN Document Server

    Tzermpinos, Konstantinos

    2013-01-01

    The scientific work presented in this paper could be described as a novel, systemic approach to the process of organization of CLIC documentation. The latter refers to the processing of various sets of archived data found on various CERN archiving services in a more friendly and organized way. From physics aspect, this is equal to having an initial system characterized by high entropy, which after some transformation of energy and matter will produce a final system of reduced entropy. However, this reduction in entropy can be considered valid for open systems only, which are sub-systems of grander isolated systems, to which the total entropy will always increase. Thus, using as basis elements from information theory, systems theory and thermodynamics, the unorganized form of data pending to be organized to a higher form, is modeled as an initial open sub-system with increased entropy, which, after the processing of information, will produce a final system with decreased entropy. This systemic approach to the ...

  18. Les mesures de métrologie pour le CLIC

    CERN Document Server

    Cherif, A

    2008-01-01

    Le projet CLIC est en tout point un défi technique majeur ; c?est le cas également pour la mesure dimensionnelle. Quels sont les équipements et les méthodes qui permettent de caractériser les pièces avec une incertitude de mesure aussi réduite que possible, vu les tolérances micrométriques imposées ? Afin de répondre à cette question, une veille technologique a été maintenue sur une longue période. Les acteurs relevants ont été contactés pour bénéficier d?une ouverture sur les dernières avancées dans le domaine. Différentes techniques ont été étudiées et comparées telles que la digitalisation, la tomographie X, la mesure tridimensionnelle. L'assemblage de haute précision des composants est aussi primordial. Sa mise en ?uvre sous un microscope optique ou à l'aide d'une machine tridimensionnelle est en cours d?étude. L'exposé traitera aussi de la mesure de rugosité, un domaine où nous disposons de moyens adaptés aux exigences spécifiques du projet.

  19. The synchro laser system for the CLIC Test Facility

    International Nuclear Information System (INIS)

    The CLIC Test Facility at CERN uses a laser driven 3 GHz electron gun. Considerable effort has been spent to develop a laser system, which meets the requirements of the Test Facility. The laser is based on a diode-pumped ND:YLF mode-locked oscillator. It delivers a 250 MHz train of laser pulses at 1047 nm with a length of 6.6 ps. A phase-locked timing stabilizer is used to synchronize the laser with the rf-gun. One or two pulses are amplified to 10 mJ. The amplifier system is based on a regenerative amplifier and two single pass power amplifiers. A set of harmonic generators deliver laser pulses at 523 nm, 262 nm and optional at 209nm. The measured pulse length after amplification and harmonic generations is 8 ± 2 ps (FWHM). A good pointing stability and a reasonable uniform transverse profile is obtained by relay imaging and spatial filtering. For some experiments, a train of electron bunches is used. A new pulse train generator working at 262 nm was developed to split the laser beam into 12 pulses. The simultaneous amplification of two seed laser pulses gives the possibility to double the number of pulses in the train without the need to add further splitting stages

  20. Progressive hearing loss and vestibular dysfunction caused by a homozygous nonsense mutation in CLIC5.

    Science.gov (United States)

    Seco, Celia Zazo; Oonk, Anne M M; Domínguez-Ruiz, María; Draaisma, Jos M T; Gandía, Marta; Oostrik, Jaap; Neveling, Kornelia; Kunst, Henricus P M; Hoefsloot, Lies H; del Castillo, Ignacio; Pennings, Ronald J E; Kremer, Hannie; Admiraal, Ronald J C; Schraders, Margit

    2015-02-01

    In a consanguineous Turkish family diagnosed with autosomal recessive nonsyndromic hearing impairment (arNSHI), a homozygous region of 47.4 Mb was shared by the two affected siblings on chromosome 6p21.1-q15. This region contains 247 genes including the known deafness gene MYO6. No pathogenic variants were found in MYO6, neither with sequence analysis of the coding region and splice sites nor with mRNA analysis. Subsequent candidate gene evaluation revealed CLIC5 as an excellent candidate gene. The orthologous mouse gene is mutated in the jitterbug mutant that exhibits progressive hearing impairment and vestibular dysfunction. Mutation analysis of CLIC5 revealed a homozygous nonsense mutation c.96T>A (p.(Cys32Ter)) that segregated with the hearing loss. Further analysis of CLIC5 in 213 arNSHI patients from mostly Dutch and Spanish origin did not reveal any additional pathogenic variants. CLIC5 mutations are thus not a common cause of arNSHI in these populations. The hearing loss in the present family had an onset in early childhood and progressed from mild to severe or even profound before the second decade. Impaired hearing is accompanied by vestibular areflexia and in one of the patients with mild renal dysfunction. Although we demonstrate that CLIC5 is expressed in many other human tissues, no additional symptoms were observed in these patients. In conclusion, our results show that CLIC5 is a novel arNSHI gene involved in progressive hearing impairment, vestibular and possibly mild renal dysfunction in a family of Turkish origin. PMID:24781754

  1. Status of the Stripline Beam Position Monitor developement for the CLIC Drive Beam

    CERN Document Server

    Benot-Morell, A; Wendt, M; Faus-Golfe, A; Nappa, J M; Vilalte, S; Smith, S

    2013-01-01

    In collaboration with SLAC, LAPP and IFIC, a first prototype of a stripline Beam Position Monitor (BPM) for the CLIC Drive Beam and its associated readout electronics has been successfully tested in the CLIC Test Facility linac (CTF3) at CERN. In addition, a modified prototype with downstream terminated striplines is under development to improve the suppression of unwanted RF signal interference. This paper presents the results of the beam tests, and the most relevant aspects for the modified stripline BPM design and its expected improvements.

  2. Experimental tests on the air cooling of the CLIC vertex detector

    CERN Document Server

    Duarte Ramos, Fernando; Nuiry, Francois-Xavier

    2016-01-01

    The strict requirements in terms of material budget for the inner region of the CLIC detector concept require the use of a dry gas for the cooling of the respective sensors. This, in conjunction with the compactness of the inner volumes, poses several challenges for the design of a cooling system that is able to fulfil the required detector specifications. This note summarizes the results obtained from experimental tests on the air cooling of the CLIC vertex detector as well as their comparison with the corresponding computational fluid dynamics simulations.

  3. X-band crab cavities for the CLIC beam delivery system

    OpenAIRE

    Burt, Graeme; Ambattu, Praveen; Dexter, Amos; Abram, Thomas; Dolgashev, V.; Tantawi, S.; Jones, R. M.

    2008-01-01

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to m...

  4. Collective effects and experimental verification of the CLIC drive beam and decelerator

    OpenAIRE

    2014-01-01

    The Compact Linear Collider (CLIC) is a potential next-generation particle collider, in which electrons and positrons collide at a center-of-mass energy of up to 3 TeV. In order to reach a high accelerating gradient and reduce the length of the machine, CLIC uses a novel two-beam scheme. Here, the acceleration energy for the main beam is provided by energy extraction from a secondary electron drive beam, by the use of Power Extraction and Transfer Structures (PETS). This Ph.D. thesis descr...

  5. High Frequency Effects of Impedances and Coatings in the CLIC Damping Rings

    CERN Document Server

    Koukovini Platia, Eirini; Rumolo, G

    The Compact Linear Collider (CLIC) is a 3 TeV eÅe¡ machine, currently under design at CERN, that targets to explore the terascale particle physics regime. The experiment requires a high luminosity of 2£1034 cm2 s¡1, which can be achieved with ultra low emittances delivered from the Damping Rings (DRs) complex. The high bunch brightness of the DRs gives rise to several collective effects that can limit the machine performance. Impedance studies during the design stage of the DR are of great importance to ensure safe operation under nominal parameters. As a first step, the transverse impedance model of the DRis built, accounting for the wholemachine. Beam dynamics simulations are performedwith HEADTAIL to investigate the effect on beam dynamics. For the correct impedancemodeling of the machine elements, knowledge of the material properties is essential up to hundreds of GHz, where the bunch spectrum extends. Specifically, Non Evaporable Getter (NEG) is a commonly used coating for good vacuumbut its properti...

  6. Transverse Beam Polarizationas an Alternate View into New Physics at CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, Thomas G.; /SLAC

    2011-08-12

    In e{sup +}e{sup -} collisions, transverse beam polarization can be a useful tool in studying the properties of particles associated with new physics beyond the Standard Model(SM). However, unlike in the case of measurements associated with longitudinal polarization, the formation of azimuthal asymmetries used to probe this physics in the case of transverse polarization requires both e{sup {+-}} beams to be simultaneously polarized. In this paper we discuss the further use of transverse polarization as a probe of new physics models at a high energy, {radical}s = 3 TeV version of CLIC. In particular, we show (i) how measurements of the sign of these asymmetries is sufficient to discriminate the production of spin-0 supersymmetric states from the spin-1/2 Kaluza-Klein excitations of Universal Extra Dimensions. Simultaneously, the contribution to this asymmetry arising from the potentially large SM W{sup +}W{sup -} background can be made negligibly small. We then show (ii) how measurements of such asymmetries and their associated angular distributions on the peak of a new resonant Z{prime}-like state can be used to extract precision information on the Z{prime} couplings to the SM fermions.

  7. Development and Validation of a Multipoint Based Laser Alignment System for CLIC

    CERN Document Server

    Stern, G; Lackner, F; Mainaud-Durand, H; Piedigrossi, D; Sandomierski, J; Sosin, M; Geiger, A; Guillaume, S

    2013-01-01

    Alignment is one of the major challenges within CLIC study, since all accelerator components have to be aligned with accuracy up to 10 μm over sliding windows of 200 m. So far, the straight line reference concept has been based on stretched wires coupled with Wire Positioning Sensors. This concept should be validated through inter-comparison with an alternative solution. This paper proposes an alternative concept where laser beam acts as straight line reference and optical shutters coupled with cameras visualise the beam. The principle was first validated by a series of tests using low-cost components. Yet, in order to further decrease measurement uncertainty in this validation step, a high-precision automatised micrometric table and reference targets have been added to the setup. The paper presents the results obtained with this new equipment, in terms of measurement precision. In addition, the paper gives an overview of first tests done at long distance (up to 53 m), having emphasis on beam divergence

  8. Proposal for an alignment method of the CLIC linear accelerator - From geodesic networks to the active pre-alignment

    International Nuclear Information System (INIS)

    The compact linear collider (CLIC) is the particle accelerator project proposed by the european organization for nuclear research (CERN) for high energy physics after the large hadron collider (LHC). Because of the nano-metric scale of the CLIC leptons beams, the emittance growth budget is very tight. It induces alignment tolerances on the positions of the CLIC components that have never been achieved before. The last step of the CLIC alignment will be done according to the beam itself. It falls within the competence of the physicists. However, in order to implement the beam-based feedback, a challenging pre-alignment is required: 10 μm at 3σ along a 200 m sliding window. For such a precision, the proposed solution must be compatible with a feedback between the measurement and repositioning systems. The CLIC pre-alignment will have to be active. This thesis does not demonstrate the feasibility of the CLIC active pre-alignment but shows the way to the last developments that have to be done for that purpose. A method is proposed. Based on the management of the Helmert transformations between Euclidean coordinate systems, from the geodetic networks to the metrological measurements, this method is likely to solve the CLIC pre-alignment problem. Large scale facilities have been built and Monte-Carlo simulations have been made in order to validate the mathematical modeling of the measurement systems and of the alignment references. When this is done, it will be possible to extrapolate the modeling to the entire CLIC length. It will be the last step towards the demonstration of the CLIC pre-alignment feasibility. (author)

  9. Bounds on the electromagnetic dipole moments through the single top production at the CLIC

    CERN Document Server

    Koksal, M; Gutierrez-Rodriguez, A

    2016-01-01

    We obtain bounds on the anomalous magnetic and electric dipole moments of the $t$-quark from a future high-energy and high-luminosity linear electron positron collider, such as the CLIC, with unpolarized and polarized electron beams which are a powerful tool to determine new physics. We consider the processes $\\gamma e^- \\to \\bar t b\

  10. First magnetic test of a superconducting Nb$_{3}$Sn Wiggler magnet for CLIC

    CERN Document Server

    Schoerling, D; Fessia, P; Karppinen, M; Mazet, J; Russenschuck, S; Peiffer, P; Grau, A

    2012-01-01

    To achieve high luminosity at the collision point of the Compact Linear Collider (CLIC) the normalized horizontal and vertical emittances of the electron and positron beams must be reduced to 500 nm and4 nm before the beams enter the 1.5 TeV linear accelerators. An effective way to accomplish ultra-low emittances with only small effects on the electron polarization is using damping rings operating at 2.86GeV equipped with superconducting wiggler magnets. Only superconducting wiggler magnets meet the demanding magnetic specifications of the CLIC damping rings. Although Nb-Ti damping wiggler magnets fulfill the specifications of CLIC, Nb3Sn wiggler magnets would reach higher magnetic fields leading to even better beam properties for CLIC. Moreover, they have at the same time higher thermal and magnetic margins. Therefore, Nb3Sn wiggler magnets are under investigation at CERN despite the challenging manufacturing process. This paper presents first results of Nb3Sn coils and short model tests and outlines the fur...

  11. Wakefield and surface electromagnetic field optimisation of manifold damped accelerating structures for CLIC

    International Nuclear Information System (INIS)

    The main travelling wave linacs of the compact linear collider (CLIC) operate at a frequency of 11.9942 GHz with a phase advance per cell of 2π/3. In order to minimise the overall footprint of the accelerator, large accelerating gradients are sought. The present baseline design for the main linacs of CLIC demands an average electric field of 100 MV/m. To achieve this in practical cavities entails the dual challenges of minimising the potential for electrical breakdown and ensuring the beam excited wakefield is sufficiently suppressed. We present a design to meet both of these conditions, together with a description of the structure, CLICDDSA, expressively designed to experimentally test the ability of the structure to cope with high powers.

  12. Technologies and R&D for a High Resolution Cavity BPM for the CLIC Main Beam

    CERN Document Server

    Towler, J R; Soby, L; Wendt, M; Boogert, S T; Cullinan, F J; Lyapin, A

    2013-01-01

    The Main Beam (MB) linac of the Compact Linear Collider (CLIC) requires a beam orbit measurement system with high spatial (50 nm) and high temporal resolution (50 ns) to resolve the beam position within the 156 ns long bunch train, traveling on an energy-chirped, minimum dispersive trajectory. A 15 GHz prototype cavity BPM has been commissioned in the probe beam-line of the CTF3 CLIC Test Facility. We discuss performance and technical details of this prototype installation, including the 15 GHz analogue downconverter, the data acquisition and the control electronics and software. An R&D outlook is given for the next steps, which requires a system of 3 cavity BPMs to investigate the full resolution potential.

  13. Correction of beam-beam effects in luminosity measurement in the forward region at CLIC

    CERN Document Server

    Lukic, Strahinja

    2013-01-01

    Procedures for correcting the beam-beam effects in luminosity measurement at CLIC at 3 TeV CM energy are described and tested using Monte Carlo simulations: -> Correction of the angular counting loss due to the combined Beamstrahlung and initial-state radiation (ISR) effects, based on the reconstructed velocity of the collision frame of the Bhabha scattering. -> Deconvolution of the luminosity spectrum distortion due to the ISR emission. -> Correction of the counting bias due to the finite calorimeter energy resolution. All procedures were tested by simulation. Bhabha events were generated using BHLUMI, and used in Guinea-PIG to simulate the outgoing momenta of Bhabha particles in the bunch collisions at CLIC. Residual uncertainties after correction are listed in a table in the conclusions. The beam-beam related systematic counting uncertainty in the luminosity peak can be reduced to the order of permille.

  14. Correction of beam-beam effects in luminosity measurement in the forward region at CLIC

    CERN Document Server

    Lukic, Strahinja

    2013-01-01

    Procedures for correcting the beam-beam effects in luminosity measurement at CLIC at 3 TeV CM energy are described and tested using Monte Carlo simulations: - Correction of the angular counting loss due to the combined Beamstrahlung and initial-state radiation (ISR) effects, based on the reconstructed velocity of the collision frame of the Bhabha scattering. - Deconvolution of the luminosity spectrum distortion due to the ISR emission. - Correction of the counting bias due to the finite calorimeter energy resolution. All procedures were tested by simulation. Bhabha events were generated using BHLUMI, and used in Guinea-PIG to simulate the outgoing momenta of Bhabha particles in the bunch collisions at CLIC. Residual uncertainties after correction are listed in a table in the conclusions. The beam-beam related systematic counting uncertainty in the luminosity peak can be reduced to the order of permille.

  15. Beam dynamics and wakefield suppression in interleaved damped and detuned structures for CLIC

    CERN Document Server

    D'Elia, A; Khan, V F; Jones, R M; Latina, A; Nesmiyan, I; Riddone, G

    2013-01-01

    Acceleration of multiple bunches of charged particles in the main linacs of the Compact Linear Collider (CLIC) with high accelerating fields provides two major challenges: firstly, to ensure the surface electromagnetic fields do not cause electrical breakdown and subsequent surface damage, and secondly, to ensure the beam-excited wakefields are sufficiently suppressed to avoid appreciable emittance dilution. In the baseline design for CLIC, heavy wakefield suppression is used (Q ~ 10) [1] and this ensures the beam quality is well-preserved [2]. Here we discuss an alternative means to suppress the wakefield which relies on strong detuning of the cell dipole frequencies, together with moderate damping, effected by manifolds which are slot-coupled to each accelerating cell. This damped and detuned wakefield suppression scheme is based on the methodology developed for the Japanese Linear Collider/Next Linear Collider (JLC/NLC) [3]. Here we track the multi-bunch beam down the complete collider, u...

  16. Status of vertex and tracking detector R&D at CLIC

    CERN Document Server

    Firu, Elena

    2015-01-01

    The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the bunch train structure of the beam and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few micron, ultra-low mass (~0.2% X0 per layer for the inner vertex region), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ~10 ns time stamping capabilities. An overview of the R&D program for pixel and tracking detectors at CLIC will be presented, including recent results on an innovative hybridisation concept based on capacitive coupling between active sensors (HV-CMOS) and readout ASICs (CLICpix).

  17. Design of the Injection and extraction system and related machine protection for the Clic Damping Rings

    CERN Document Server

    Apsimon, Robert; Barnes, Mike; Borburgh, Jan; Goddard, Brennan; Papaphilippou, Yannis; Uythoven, Jan

    2014-01-01

    Linear machines such as CLIC have relatively low rates of collision between bunches compared to their circular counterparts. In order to achieve the required luminosity, a very small spot size is envisaged at the interaction point, thus a low emittance beam is needed. Damping rings are essential for producing the low emittances needed for the CLIC main beam. It is crucial that the beams are injected and extracted from the damping rings in a stable and repeatable fashion to minimise emittance blow-up and beam jitter at the interaction point; both of these effects will deteriorate the luminosity at the interaction point. In this paper, the parameters and constraints of the injection and extraction systems are considered and the design of these systems is optimised within this parameter space. Related machine protection is considered in order to prevent damage from potential failure modes of the injection and extraction systems.

  18. Laser Wire Scanner Basic Process and Perspectives for the CTF's and CLIC Machines

    CERN Document Server

    Lefèvre, T

    2002-01-01

    In a laser wire scanner, the basic idea is to replace the solid wire classically used in a standard wire scanner by a narrow laser beam. The basic process involved is the Thomson-Compton scattering process, where photons are scattered from the laser beam by the incoming electrons. By counting the number of scattered photons or degraded electrons as a function of laser position the bunch profile can be reconstructed. In this note the Compton scattering mechanism is first presented. In the framework of the CLIC project, a laser wire scanner (LWS) could be used as a non-interfering beam profile measurement both on the Drive Beam for a high current electron beam and on the Main Beam for very small electron beam sizes. A design for a LWS on the CTF2 and CTF3 machines is proposed and some considerations for the use of a LWS on the CLIC main beam are also mentioned.

  19. Analyzing the Anomalous Dipole Moment Type Couplings of Heavy Quarks with FCNC Interactions at the CLIC

    International Nuclear Information System (INIS)

    We examine both anomalous magnetic and dipole moment type couplings of a heavy quark via its single production with subsequent dominant standard model decay modes at the compact linear collider (CLIC). The signal and background cross sections are analyzed for heavy quark masses 600 and 700 GeV. We make the analysis to delimitate these couplings as well as to find the attainable integrated luminosities for 3σ observation limit

  20. Gluino Pair Production in $e^+ e^-$ and Photon-Photon Collisions at CERN CLIC

    CERN Document Server

    Berge, S; 10.1140/epjc/s2003-01194-4

    2003-01-01

    We confront the generally small cross sections for gluino pair production in e^+e^- annihilation with the much larger ones in photon-photon scattering at a multi-TeV linear collider like CERN CLIC. The larger rates and the steeper rise of the cross section at threshold may allow for a precise gluino mass determination in high-energy photon-photon collisions for a wide range of squark masses and post-LEP SUSY benchmark points.

  1. The Event Display for CLIC: DD4hep Compatibility and Improvements

    CERN Document Server

    Quast, Thorben

    2015-01-01

    This document is a short summary of my contributions to the Event Display for the CLICdp Software group in the context of CERN’s Summer Student Programme 2015. After a brief outline of CLIC and the relevant software package, the project is motivated. The individual achievements and their technical realizations are explained rather qualitatively, as details are well documented directly in the source code.

  2. ACE3P Computations of Wakefield Coupling in the CLIC Two-Beam Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; Grudiev, A.; Wuensch, W.; /CERN

    2010-10-27

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its novel two-beam accelerator concept envisions rf power transfer to the accelerating structures from a separate high-current decelerator beam line consisting of power extraction and transfer structures (PETS). It is critical to numerically verify the fundamental and higher-order mode properties in and between the two beam lines with high accuracy and confidence. To solve these large-scale problems, SLAC's parallel finite element electromagnetic code suite ACE3P is employed. Using curvilinear conformal meshes and higher-order finite element vector basis functions, unprecedented accuracy and computational efficiency are achieved, enabling high-fidelity modeling of complex detuned structures such as the CLIC TD24 accelerating structure. In this paper, time-domain simulations of wakefield coupling effects in the combined system of PETS and the TD24 structures are presented. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel CLIC two-beam accelerator scheme.

  3. X-band crab cavities for the CLIC beam delivery system

    CERN Document Server

    Burt, G; Dexter, A C; Abram, T; Dolgashev, V; Tantawi, S; Jones, R M

    2009-01-01

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to minimise beam loading and mode separation. The position of the crab cavity close to the final focus enhances the effect of transverse wake-fields so effective wake-field damping is required. A damped detuned structure is proposed to suppress and de-cohere the wake-field hence reducing their effect. Design considerations for the CLIC crab cavity will be discussed as well as the proposed high power testing of these structures at SLAC.

  4. En route vers la nano stabilisation de CLIC faisceau principale et focalisation finale

    CERN Document Server

    Artoos, K; Guinchard, M; Hauviller, Claude; Lackner, F; CERN. Geneva. TS Department

    2008-01-01

    Pour atteindre la luminosité voulue de CLIC, la taille transversale du faisceau doit être de l?ordre du nanomètre. Ceci nécessite une stabilité vibratoire des quadripôles du faisceau principal de 1 nm et même 0.1 nm pour les doublets de la focalisation finale. La nano technologie et la nano stabilisation sont des activités qui évoluent rapidement dans l?industrie et centres de recherche pour des applications très variées comme l?électronique, l?optique, la chimie voire la médecine. Cette présentation décrit les avancées techniques nécessaires pour atteindre l?objectif de CLIC et les projets et collaborations R&D prévus pour démontrer la faisabilité de la nano stabilisation de CLIC en 2010.

  5. Klystron Modulators for the 3 TeV CLIC Scheme An Overview

    CERN Document Server

    Pearce, P

    2001-01-01

    The CLIC (Compact Linear Collider) design is based on the Two-Beam technology being developed at CERN. The Drive Beam accelerator will have about 200 multi-beam klystron-modulator (MBK-M) RF power sources for each drive beam linac. These multi-beam klystrons (MBKs) should provide up to 50 MW peak power at 937 MHz, with a 100 ms pulse width and operating at 100 Hz repetition frequency. The CLIC drive beam injector will also use a number of these same MBK-Ms operating at slightly lower power levels. A 0.5 MW peak power, 468 MHz klystron with a bandwidth of around 150 MHz will be required for the sub-harmonic buncher in each drive beam injector chain as well. The Main Beams injector complex is required to deliver e+ and e- beams at 9 GeV via the transfer lines to the CLIC Main Beam accelerator. The present injector complex design uses a series of linacs to accelerate the electron and positron beams coming from RF guns working at 1.5 GHz up to an energy of 1.98 GeV before they are put into damping rings. Each of ...

  6. CERN balances linear collider studies

    CERN Multimedia

    ILC Newsline

    2011-01-01

    The forces behind the two most mature proposals for a next-generation collider, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC) study, have been steadily coming together, with scientists from both communities sharing ideas and information across the technology divide. In a support of cooperation between the two, CERN in Switzerland, where most CLIC research takes place, recently converted the project-specific position of CLIC Study Leader to the concept-based Linear Collider Study Leader.   The scientist who now holds this position, Steinar Stapnes, is charged with making the linear collider a viable option for CERN’s future, one that could include either CLIC or the ILC. The transition to more involve the ILC must be gradual, he said, and the redefinition of his post is a good start. Though not very much involved with superconducting radiofrequency (SRF) technology, where ILC researchers have made significant advances, CERN participates in many aspect...

  7. Progressive hearing loss and vestibular dysfunction caused by a homozygous nonsense mutation in CLIC5

    OpenAIRE

    Seco, Celia Zazo; Oonk, Anne MM; Domínguez-Ruiz, María; Draaisma, Jos MT; Gandía, Marta; Oostrik, Jaap; Neveling, Kornelia; Kunst, Henricus PM; Hoefsloot, Lies H.; del Castillo, Ignacio; Pennings, Ronald JE; Kremer, Hannie; Admiraal, Ronald JC; Schraders, Margit

    2014-01-01

    In a consanguineous Turkish family diagnosed with autosomal recessive nonsyndromic hearing impairment (arNSHI), a homozygous region of 47.4 Mb was shared by the two affected siblings on chromosome 6p21.1-q15. This region contains 247 genes including the known deafness gene MYO6. No pathogenic variants were found in MYO6, neither with sequence analysis of the coding region and splice sites nor with mRNA analysis. Subsequent candidate gene evaluation revealed CLIC5 as an excellent candidate gen...

  8. Feed Forward Orbit Correction in the CLIC Ring to Main LINAC Transfer lines

    CERN Document Server

    Apsimon, R; Schulte, D; Uythoven, J

    2014-01-01

    The emittance growth in the betatron collimation system of the 27 km long transfer lines between the CLIC damping rings and the main LINAC depends strongly on the transverse orbit jitter. The resulting stability requirements of the damping ring extraction elements seem extremely difficult to achieve. Position and angle feed forward systems in these long transfer lines bring the specified parameters of the extraction elements within reach. The designs of the optics and feed forward hardware are presented together with tracking simulations of the systems.

  9. Evaluation of 65nm technology for CLIC pixel front-end

    CERN Document Server

    Valerio, P; Ballabriga, R; Campbell, M; Llopart, X

    2011-01-01

    The CLIC vertex detector design requires a high single point resolution (~ 3 μm) and a precise time stamp (≤ 10 ns). In order to achieve this spatial resolution, small pixels (in the order of 20 μm pitch) must be used, together with the measurement of the charge deposition of neighbouring channels. Designing such small pixels requires the use of a deep downscaled CMOS technology. This note describes the design and characterisation of suitable building blocks implemented in a commercial 65 nm process. The characterisation included an evaluation of the radiation hardness of the blocks.

  10. The chloride intracellular channel protein CLIC5 is expressed at high levels in hair cell stereocilia and is essential for normal inner ear function.

    Science.gov (United States)

    Gagnon, Leona H; Longo-Guess, Chantal M; Berryman, Mark; Shin, Jung-Bum; Saylor, Katherine W; Yu, Heping; Gillespie, Peter G; Johnson, Kenneth R

    2006-10-01

    Although CLIC5 is a member of the chloride intracellular channel protein family, its association with actin-based cytoskeletal structures suggests that it may play an important role in their assembly or maintenance. Mice homozygous for a new spontaneous recessive mutation of the Clic5 gene, named jitterbug (jbg), exhibit impaired hearing and vestibular dysfunction. The jbg mutation is a 97 bp intragenic deletion that causes skipping of exon 5, which creates a translational frame shift and premature stop codon. Western blot and immunohistochemistry results confirmed the predicted absence of CLIC5 protein in tissues of jbg/jbg mutant mice. Histological analysis of mutant inner ears revealed dysmorphic stereocilia and progressive hair cell degeneration. In wild-type mice, CLIC5-specific immunofluorescence was detected in stereocilia of both cochlear and vestibular hair cells and also along the apical surface of Kolliker's organ during cochlear development. Refined immunolocalization in rat and chicken vestibular hair cells showed that CLIC5 is limited to the basal region of the hair bundle, similar to the known location of radixin. Radixin immunostaining appeared reduced in hair bundles of jbg mutant mice. By mass spectrometry and immunoblotting, CLIC5 was shown to be expressed at high levels in stereocilia of the chicken utricle, in an approximate 1:1 molar ratio with radixin. These results suggest that CLIC5 associates with radixin in hair cell stereocilia and may help form or stabilize connections between the plasma membrane and the filamentous actin core. PMID:17021174

  11. Preliminary Design of a Bunching System for the CLIC Polarized Electron Source

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Feng

    2009-10-30

    Major parameters of the CLIC and ILC electron sources are given in Table I. It is shown that the CLIC source needs to provide 312 15-ps-long 2-GHz microbunches. There are two approaches to achieve the time structure [2]: one is to develop a 2-GHz optical pulse train, and the other to develop a 156-ns-long CW optical pulse and use an RF bunching system to generate 312 2-GHz microbunches. The former scheme may ease the RF bunching system but still need it to bunch 100-ps of microbunch down to 15-ps level. Otherwise, a huge amount of energy spread is accumulated when the beam is accelerated through downstream 2-GHz accelerator. In addition, in the former scheme, the space charge is high and surface charge is not yet proven in the parameter regime and 2-GHz mode locked laser is challenging. The latter scheme needs a high-efficiency bunching system to generate 312 15-ps microbunches with 2-GHz repetition rate but it has some notable advantages: a 156-ns CW laser technique is matured, and the charge limit behavior in the scheme is better characterized than that in the former case, as listed in the table. This note presents a design and modeling of the bunching system for the latter scheme to convert a 156-ns CW pulse to 312 15-ps long 2-GHz microbunches.

  12. Fast Beam-ion Instabilities in CLIC Main Linac Vacuum Specifications

    CERN Document Server

    Oeftiger, Adrian

    2011-01-01

    Specifications for the vacuum pressure in the CLIC electron Main Linac are determined by the onset of the fast beam-ion instability (FBII). When the electron beam is accelerated in the Main Linac, it ionizes the residual gas in the chamber through scattering ionization. If the density of ions around the beam exceeds a certain threshold, a resonant motion between the electron beam and the ions can be excited. A two-stream instability appears and as a result the beam acquires a coherent motion, which can quickly lead to beam quality degradation or even complete loss. Thus, the vacuum pressure must be kept below this threshold to prevent the excitation of FBII. The CLIC Main Linac poses an additional challenge with respect to previous FBII situations, because the gas ionization does not solely occur via scattering. The submicrometric beam sizes lead to extremely high electric fields around the beam and therefore result in field ionization beyond a certain threshold. The residual gas in the corresponding volume a...

  13. Stabilisation and precision pointing quadrupole magnets in the Compact Linear Collider (CLIC)

    CERN Document Server

    Janssens, Stef; van den Brand, Jo; Bertolini, Alessandro; Artoos, Kurt

    This thesis describes the research done to provide stabilisation and precision positioning for the main beam quadrupole magnets of the Compact Linear Collider CLIC. The introduction describes why new particle accelerators are needed to further the knowledge of our universe and why they are linear. A proposed future accelerator is the Compact Linear Collider (CLIC) which consists of a novel two beam accelerator concept. Due to its linearity and subsequent single pass at the interaction point, this new accelerator requires a very small beam size at the interaction point, in order to increase collision effectiveness. One of the technological challenges, to obtain these small beam sizes at the interaction point, is to keep the quadrupole magnets aligned and stable to 1.5 nm integrated r.m.s. in vertical and 5 nm integrated root mean square (r.m.s.) in lateral direction. Additionally there is a proposal to create an intentional offset (max. 50 nm every 20 ms with a precision of +/- 1 nm), for several quadrupole ma...

  14. CLIC Main Linac Beam-Loading Compensation by Drive Beam Phase Modulation

    CERN Document Server

    Corsini, R; Syratchev, I V

    1999-01-01

    The CLIC final focus momentum acceptance of ± 0.5 % limits the bunch-to-bunch energy variation in the main beam to less than ± 0.1 %, since the estimated single-bunch contribution is ± 0.4 %. On the other hand, a relatively high beam-loading of the main accelerating structures (about 16 %) is unavoidable in order to optimize the RF-to-beam efficiency. Therefore, a compensation method is needed to reduce the resulting bunch-to-bunch energy spread of the main beam. Up to now, it has been planned to obtain the RF pulse shape needed for compensation by means of a charge ramp in the drive beam pulse. On the other hand, the use of constant-current drive beam pulses would make the design and operation of the drive beam injector considerably simpler. In this paper we present a possible solution adapted to the CLIC two-beam scheme with constant-current pulses, based on phase modulation of the drive beam bunches.

  15. $2\\times250$ GeV CLIC $\\gamma\\gamma$ Collider Based on its Drive Beam FEL

    CERN Document Server

    Aksakal, Husnu

    2007-01-01

    CLIC is a linear $e^+e^-$ ($\\gamma\\gamma$) collider project which uses a drive beam to accelerate the main beam. The drive beam provides RF power for each corresponding unit of the main linac through energy extracting RF structures. CLIC has a wide range of center-of-mass energy options from 150 GeV to 3 TeV. The present paper contains optimization of Free Electron Laser (FEL) using one bunch of CLIC drive beam in order to provide polarized light amplification using appropriate wiggler and luminosity spectrum of $\\gamma\\gamma$ collider for $E_{cm}$=0.5 TeV. Then amplified laser can be converted to a polarized high-energy $\\gamma$ beam at the Conversion point (CP-prior to electron positron interaction point) in the process of Compton backscattering. At the CP a powerful laser pulse (FEL) focused to main linac electrons (positrons). Here this scheme described and it is show that CLIC drive beam parameters satisfy the requirement of FEL additionally essential undulator parameters has been defined. Achievable $\\g...

  16. Prospects for the measurement of the Higgs Yukawa couplings to b and c quarks, and muons at CLIC

    Czech Academy of Sciences Publication Activity Database

    Grefe, C.; Laštovička, Tomáš; Strube, J.

    2013-01-01

    Roč. 73, č. 2 (2013), s. 1-7. ISSN 1434-6044 Institutional support: RVO:68378271 Keywords : Higgs * branching * ratio * Yukawa * couplings * quarks * muons * CLIC * inear collider Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 5.436, year: 2013

  17. Physics potential for the measurement of σ(Hνν{sup -bar})×BR(H→μ{sup +}μ{sup -}) at the 1.4 TeV CLIC collider

    Energy Technology Data Exchange (ETDEWEB)

    Milutinović-Dumbelović, G., E-mail: gordanamd@vinca.rs; Božović-Jelisavčić, I. [Vinca Institute of Nuclear Sciences, University of Belgrade, Mihajla Petrovića Alasa 12-14, 11001, Belgrade (Serbia); Grefe, C. [Universität Bonn, 53012, Bonn (Germany); CERN, 1211, Geneva 23 (Switzerland); Kačarević, G.; Lukić, S.; Pandurović, M. [Vinca Institute of Nuclear Sciences, University of Belgrade, Mihajla Petrovića Alasa 12-14, 11001, Belgrade (Serbia); Roloff, P. [CERN, 1211, Geneva 23 (Switzerland); Smiljanić, I. [Vinca Institute of Nuclear Sciences, University of Belgrade, Mihajla Petrovića Alasa 12-14, 11001, Belgrade (Serbia)

    2015-10-30

    The future compact linear collider (CLIC) offers a possibility for a rich precision physics programme, in particular in the Higgs sector through the energy staging. This is the first paper addressing the measurement of the standard model Higgs boson decay into two muons at 1.4 TeV CLIC. With respect to similar studies at future linear colliders, this paper includes several novel contributions to the statistical uncertainty of the measurement. The latter includes the equivalent photon approximation employed to describe e{sup +}e{sup -} and eγ interactions whenever the virtuality of the mediated photon is smaller than 4 GeV and realistic forward electron tagging based on energy deposition maps in the forward calorimeters, as well as several processes with the Beamstrahlung photons that results in irreducible contribution to the signal. In addition, coincidence of the Bhabha scattering with the signal and background processes is considered, altering the signal selection efficiency. The study is performed using a fully simulated CLIC-ILD detector model. It is shown that the branching ratio for the Higgs decay into a pair of muons BR(H→μ{sup +}μ{sup -}) times the Higgs production cross-section in WW-fusion σ(Hνν{sup -bar}) can be measured with 38 % statistical accuracy at √s=1.4 TeV, assuming an integrated luminosity of 1.5 ab{sup -1} with unpolarised beams. If 80 % electron beam polarisation is considered, the statistical uncertainty of the measurement is reduced to 25 %. Systematic uncertainties are negligible in comparison to the statistical uncertainty.

  18. 补体成分 C3及其缺失突变体蛋白的表达及与 CLIC1蛋白共定位的研究%The expression of human complement component C3 and its deletion mutants and the colocalization with CLIC1

    Institute of Scientific and Technical Information of China (English)

    王二宁; 陈丹丹; 刘晓颖; 范礼斌

    2015-01-01

    目的:研究补体成分 C3及其缺失突变体 C3(1-840)、C3(824-1663)在真核细胞内的表达及与氯离子通道蛋白(CLIC1)的共定位。方法构建 pcDNA3.1-C3-FLAG、pcDNA3.1-C3(1-840)-FLAG、pcDNA3.1-C3(824-1663)-FLAG 三个真核表达质粒(缺失突变体根据 C3的结构域及其裂解断裂位置设计),并分别转染至 HEK 293T 细胞中, Western blot 检测表达情况;上述质粒分别瞬时单转至 COS7细胞和分别与 GFP-CLIC1共转至 COS7细胞内,观察共定位情况。结果成功构建带 FLAG 标签的 C3基因及其两个缺失突变体[C3(1-840)、C3(824-1663)]的真核表达载体, Western blot 结果显示它们在 HEK 293T 细胞中均能成功表达;免疫荧光显示它们在 COS7细胞中均主要分布于细胞质,且三个真核表达载体中只有 C3(824-1663)与 CLIC1有共定位。结论补体 C3及其缺失突变体 C3(1-840)和 C3(824-1663)在 HEK 293T、COS7细胞中均能高效表达,且主要分布在细胞质内,C3(824-1663)与 CLIC1蛋白有共定位。%Objective To study the expression and cell localization of complement component C3 and its deletion mutants C3(1-840)and C3(824-1663)in eukaryotic cells and the colocalization with CLIC1.Methods To con-struct three eukaryotic expression plasmids of pcDNA3.1-C3-FLAG,pcDNA3.1-C3(1-840)-FLAG and pcDNA3.1-C3(824-1663)-FLAG(according to C3 structure domain and splitting position).The plasmids were transfected into HEK 293T cells.Then the expression was detected by Western blot,and their cellular localization was detected in COS7 cells by fluorescence microscopy.Results The eukaryotic expression plasmids of pcDNA3.1-C3-FLAG, pcDNA3.1-C3(1-840)-FLAG and pcDNA3.1-C3(824-1663)-FLAG were constructed successfully,which could be expressed in HEK 293T and COS7 cells,and the cellular localization of C3 and C3(1-840),C3(824-1663)ap-peared similar,mainly in the cytoplasm,and only C3(824-1663)co

  19. 'Click Rural' - the rural program for rural electrification: his effects and implications the western Parana, Brazil after 20 years later; O programa de eletrificacao rural 'Clic rural': seus efeitos e implicacoes na regiao oeste do Parana 20 anos depois

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Celso Eduardo Lins de [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Dept. de Engenharia de Alimentos; Halmeman, Maria Cristina Rodrigues

    2006-07-01

    This study verified through a sampling the technical standard of attendance adopted by the greater program for rural electrification denominated 'Clic Rural' ever implanted in the state of Parana, Brazil, in the period of 1984-1992 at the concession area of COPEL - Parana Energy Company. The work was based on a field research with visits and a questionnaire applied of rural proprietaries.

  20. Beam Tests of a Prototype Stripline Beam Position Monitoring System for the Drive Beam of the CLIC Two-beam Module at CTF3

    CERN Document Server

    Benot-Morell, Alfonso; Nappa, Jean-Marc; Vilalte, Sebastien; Wendt, Manfred

    2016-01-01

    In collaboration with LAPP and IFIC, two units of a prototype stripline Beam Position Monitor (BPM) for the CLIC Drive Beam (DB), and its associated readout electronics have been successfully installed and tested in the Two-Beam-Module (TBM) at the CLIC Test Facility 3 (CTF3) at CERN. This paper gives a short overview of the BPM system and presents the performance measured under different Drive Beam configurations.

  1. Proposition d'une méthode d'alignement de l'accélérateur linéaire CLIC

    CERN Document Server

    Touzé, Thomas; Mainaud-Durand, H

    2011-01-01

    The compact linear collider (CLIC) is the particles accelerator project proposed by the european organization for nuclear research (CERN) for high energy physics after the large hadron collider (LHC). Because of the nanometric scale of the CLIC leptons beams, the emittance growth budget is very tight. It induces alignment tolerances on the positions of the CLIC components that have never been achieved. The last step of the CLIC alignment will be done according to the beam itself. It falls within the competence of the physicists. However, in order to implement the beam-based feedback, a challenging pre-alignment is required : 10 μm at 3σ along a 200 m sliding window. For such a precision, the proposed solution must be compatible with a feedback between the measurement and repositioning systems. The CLIC pre-alignment will have to be active. This thesis does not demonstrate the feasibility of the CLIC active prealignment but shows the way to the last developments that have to be done for that purpose. A metho...

  2. The Climate and Cryosphere Project (CliC): Helping bring sea ice Models and Observations together.

    Science.gov (United States)

    Lytle, V.; Goodison, B.; Worby, A.; Ryabinin, V.; Prick, A.; Villinger, T.

    2007-12-01

    The Climate and Cryosphere Project is sponsored by the World Climate Research Program (WCRP) and the Scientific Committee for Antarctic Research (SCAR). One of the four themes within the CliC project is the Marine Cryosphere Theme (MarC). This paper will review the recent projects and workshops held within this Theme and how they relate to other, international initiatives. Recent recommendations on sea ice thickness are being implemented, and groups have been formed to work towards improvements in models, particularly in their representation of the Southern Ocean. SOPHOCLES (Southern Ocean Physical Oceanography and Cryosphere Processes and Climate) will work with other modeling groups to improve the representation of the Southern Ocean in climate models. This will include cooperation with other modeling and observational groups to develop metrics to help evaluate models. In the Arctic, we are working to help develop, standardize, and implement observation and measurement protocols for Arctic sea ice in coastal, seasonal, and perennial ice zones.

  3. Present status of development of damping ring extraction kicker system for CLIC

    CERN Document Server

    Holma, Janne; Belver-Aguilar, Caroline; Faus-Golfe, Angeles; Toral, Fernando

    2012-01-01

    The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping ring kickers must provide extremely flat, high-voltage pulses: specifications call for a 160 ns duration and a flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than \\pm0.02 %. The stripline design is also extremely challenging: the field for the damping ring kicker system must be homogenous to within \\pm0.01 % over a 1 mm radius, and low beam coupling impedance is required. The solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications for the field pulse ripple and droop. This paper describes the initial design of the inductive adder and the striplines of the kicker system.

  4. Present status of development of damping ring extraction kicker system for CLIC

    CERN Document Server

    Holma, Janne; Belver-Aguilar, Caroline; Faus-Golfe, Angeles; Toral, Fernando

    2012-01-01

    The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping ring kickers must provide extremely flat, high-voltage pulses: specifications call for a 160 ns duration and a flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 %. The stripline design is also extremely challenging: the field for the damping ring kicker system must be homogenous to within ±0.01 % over a 1 mm radius, and low beam coupling impedance is required. The solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications for the field pulse ripple and droop. This paper describes the initial design of the inductive adder and the striplines of the kicker system.

  5. Experience on Fabrication and Assembly of the First CLIC Two-Beam Module Prototype

    CERN Document Server

    Gudkov, D; Riddone, G; Rossi, F; Lebet, S

    2013-01-01

    The CLIC two-beam module prototypes are intended to prove the design of all technical systems under the different operation modes. Two validation programs are currently under way and they foresee the construction of four prototype modules for mechanical tests without beam and three prototype modules for tests with RF and beam. The program without beam will show the capability of the technical solutions proposed to fulfil the stringent requirements on radio-frequency, supporting, pre-alignment, stabilization, vacuum and cooling systems. The engineering design was performed with the use of CAD/CAE software. Dedicated mock-ups of RF structures, with all mechanical interfaces and chosen technical solutions, are used for the tests and therefore reliable results are expected. The components were fabricated by applying different technologies and methods for manufacturing and joining. The first full-size prototype module was assembled in 2012. This paper is focused on the production process including the comparison o...

  6. Recent results with HV-CMOS and planar sensors for the CLIC vertex detector

    CERN Document Server

    AUTHOR|(SzGeCERN)734627

    2016-01-01

    The physics aims for the future multi-TeV e+e- Compact Linear Collider (CLIC) impose high precision requirements on the vertex detector which has to match the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of 3μm, 10 ns time stamping capabilities, low mass (⇠0.2% X0 per layer), low power dissipation and pulsed power operation. Recent results of test beam measurements and GEANT4 simulations for assemblies with Timepix3 ASICs and thin active-edge sensors are presented. The 65 nm CLICpix readout ASIC with 25μm pitch was bump bonded to planar silicon sensors and also capacitively coupled through a thin layer of glue to active HV-CMOS sensors. Test beam results for these two hybridisation concepts are presented.

  7. Imperfection Tolerances For On-line Dipsersion Free Steering in the Main LINAC of CLIC

    CERN Document Server

    Pfingstner, J; Schulte, D

    2013-01-01

    Long-term ground motion misaligns the elements of the main linac of CLIC over time. Especially the misaligned quadrupoles create dispersion and hence the beam quality is decreased gradually due to an effect called chromatic dilution. Over longer time periods, orbit feedback systems are not capable to fully recover the beam quality and have to be supplemented by dispersion correction algorithms. In this paper, such and dispersion correction algorithm is presented, which is an extended version of the well-known dispersion free steering algorithm. This extended algorithm can recover the beam quality over long time scaled without stopping the accelerator operation (on-line). Tolerances for different imperfections of the system have been identified and a strong sensitivity to the resolution of the wake field monitors of the main linac accelerating structures has been identified. This problem can be mitigated by using a local excitation scheme as will be shown in this work.

  8. Numerical Verification of the Power Transfer and Wakefield Coupling in the Clic Two-Beam Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; Grudiev, A.; Wuensch, W.; /CERN

    2011-08-19

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its two-beam accelerator (TBA) concept envisions complex 3D structures, which must be modeled to high accuracy so that simulation results can be directly used to prepare CAD drawings for machining. The required simulations include not only the fundamental mode properties of the accelerating structures but also the Power Extraction and Transfer Structure (PETS), as well as the coupling between the two systems. Time-domain simulations will be performed to understand pulse formation, wakefield damping, fundamental power transfer and wakefield coupling in these structures. Applying SLAC's parallel finite element code suite, these large-scale problems will be solved on some of the largest supercomputers available. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel two-beam accelerator scheme.

  9. Stabilization and positioning of CLIC quadrupole magnets with sub-nanometre resolution

    CERN Document Server

    Janssens, S; Collette, C; Esposito, M; Fernandez Carmona, P; Guinchard, M; Hauviller, C; Kuzmin, A; Leuxe, R; Moron Ballester, R

    2011-01-01

    To reach the required luminosity at the CLIC interaction point, about 2000 quadrupoles along each linear collider are needed to obtain a vertical beam size of 1 nm at the interaction point. Active mechanical stabilization is required to limit the vibrations of the magnetic axis to the nanometre level in a frequency range from 1 to 100 Hz. The approach of a stiff actuator support was chosen to isolate from ground motion and technical vibrations acting directly on the quadrupoles. The actuators can also reposition the quadrupoles between beam pulses with nanometre resolution. A first conceptual design of the active stabilization and nano positioning based on the stiff support and seismometers was validated in models and experimentally demonstrated on test benches. Lessons learnt from the test benches and information from integrated luminosity simulations using measured stabilization transfer functions lead to improvements of the actuating support, the sensors used and the system controller. The controller elect...

  10. CLIC simulations from the start of the linac to the interaction point

    CERN Document Server

    Schulte, Daniel; Blair, G A; D'Amico, T E; Leros, Nicolas; Redaelli, S; Risselada, Thys; Zimmermann, Frank

    2002-01-01

    Simulations for linear colliders are traditionally performed separately for the different sub-systems, like damping ring, bunch compressor, linac, and beam delivery. The beam properties are usually passed from one sub-system to the other via bunch charge, RMS transverse emittances, RMS bunch length, average energy and RMS energy spread. It is implicitly assumed that the detailed 6D correlations in the beam distribution are not relevant for the achievable luminosity. However, it has recently been shown that those correlations can have a strong effect on the beam-beam interaction. We present first results on CLIC simulations that integrate linac, beam delivery, and beam-beam interaction. These integrated simulations also allow a better simulation of time-dependent effects, like ground perturbations and interference between several beam-based feedbacks.

  11. Simulations and Vacuum Tests of a CLIC Accelerating Structure

    CERN Document Server

    Garion, C

    2011-01-01

    The Compact LInear Collider, under study, is based on room temperature high gradient structures. The vacuum specificities of these cavities are low conductance, large surface areas and a non-baked system. The main issue is to reach UHV conditions (typically 10-7 Pa) in a system where the residual vacuum is driven by water outgassing. A finite element model based on an analogy thermal/vacuum has been built to estimate the vacuum profile in an accelerating structure. Vacuum tests are carried out in a dedicated set-up, the vacuum performances of different configurations are presented and compared with the predictions.

  12. Very forward detectors for ILC and CLIC detectors

    International Nuclear Information System (INIS)

    The instrumentation of the Very Forward Regions in experiments at future linear e+e- colliders is a challenge due to high radiation fields and high rates. Two calorimeters are foreseen to perform a fast and a precise luminosity measurement and and extend the detector coverage to very low polar angles. For the calorimeter near the beampipe dedicated GaAs:Cr sensors with very good radiation tolerance were developed. For the luminometer, outside the strong radiation field, silicon sensors are foreseen. Two prototypes of sensor planes are assembled with specially developed front-end and ADC ASICS with different feedback schemes of the front-end ASIC. The performance of the full system was studied with a 4 GeV electron beam at DESY. A report of the testbeam results on relevant parameters is given.

  13. Monte Carlo simulations to estimate the damage potential of electron beam and tests of beam loss detector based on quartz Cherenkov radiator read out by a silicon photomultiplier on CLIC Test Facility 3(CTF3)

    CERN Document Server

    Orfanelli, Styliani; Gazis, E

    The Compact Linear Collider (CLIC) study is a feasibility study aiming at the development of an electron/positron linear collider with a centre of mass energy in the multi-TeV energy range. Each Linac will have a length of 21 km, which means that very high accelerating gradients (>100 MV/m) are required. To achieve the high accelerating gradients, a novel two-beam acceleration scheme, in which RF power is transferred from a high-current, low-energy drive beam to the low-current, high energy main accelerating beam is designed. A Beam Loss Monitoring (BLM) system will be designed for CLIC to meet the requirements of the accelerator complex. Its main role as part of the machine protection scheme will be to detect potentially dangerous beam instabilities and prevent subsequent injection into the main beam or drive beam decelerators. The first part of this work describes the GEANT4 Monte Carlo simulations performed to estimate the damage potential of high energy electron beams impacting a copper target. The second...

  14. Impact of the New CLIC Beam Parameters on the Design of the Post-Collision Line and its Exit Window

    CERN Document Server

    Ferrari, A

    2008-01-01

    Following the recent modification of the CLIC beam parameters, we present an updated design of the post-collision line. As a result of the increase of the beamstrahlung photon cone size, the separation of the outgoing beams by the vertical magnetic chicane is more difficult, but still possible. The main changes in the post-collision line design include the implementation of a common dump for the wrong-sign charged particles of the coherent pairs and for the low-energy tails of the disrupted beam, as well as a significant reduction of the overall lattice length (allowing removal of the large refocusing quadrupoles). The thermal and mechanical stresses in the new exit window, 150 m downstream of the interaction point, were computed. We conclude that, despite the recent changes of the CLIC beam parameters and the necessary modifications of the post-collision line and its exit window, their performance is not significantly affected.

  15. Accelerator and Technical Sector Seminar: Mechanical stabilization and positioning of CLIC quadrupoles with sub-nanometre resolution

    CERN Multimedia

    2011-01-01

    Thursday 24 November 2010 Accelerator and Technical Sector Seminar at 14:15  -  BE Auditorium, bldg. 6 (Meyrin) – please note unusual place Mechanical stabilization and positioning of CLIC quadrupoles with sub-nanometre resolution Stef Janssens /EN-MME Abstract: To reach the required luminosity at the CLIC interaction point, about 4000 quadrupoles are needed to obtain a vertical beam size of 1 nm at the interaction point. The mechanical jitter of the quadrupole magnets will result in an emittance growth. An active vibration isolation system is required to reduce vibrations from the ground and from external forces to about 1.5 nm integrated root mean square (r.m.s.) vertical displacement at 1 Hz. A short overview of vibration damping and isolation strategies will be presented as well as a comparison of existing systems. The unprecedented resolution requirements and the instruments enabling these measurements will be discussed. The vibration sources from which the magnets need to...

  16. Wakefield Simulation of CLIC PETS Structure Using Parallel 3D Finite Element Time-Domain Solver T3P

    Energy Technology Data Exchange (ETDEWEB)

    Candel, A.; Kabel, A.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; /CERN

    2009-06-19

    In recent years, SLAC's Advanced Computations Department (ACD) has developed the parallel 3D Finite Element electromagnetic time-domain code T3P. Higher-order Finite Element methods on conformal unstructured meshes and massively parallel processing allow unprecedented simulation accuracy for wakefield computations and simulations of transient effects in realistic accelerator structures. Applications include simulation of wakefield damping in the Compact Linear Collider (CLIC) power extraction and transfer structure (PETS).

  17. Instrumentation for Longitudinal Beam Gymnastics in FEL's and at the CLIC Test Facility 3

    CERN Document Server

    Lefèvre, T; Bravin, E; Burger, S; Corsini, R; Döbert, S; Soby, L; Tecker, F A; Urschutz, P; Welsch, C P; Alesini, D; Biscari, C; Buonomo, B; Coiro, O; Ghigo, A; Marcellini, F; Preger, B; Dabrowski, A; Velasco, M; Craievich, P; Ferianis, M; Veronese, M; Ferrari, A

    2008-01-01

    Built at CERN by an international collaboration, the CLIC Test Facility 3 (CTF3) aims at demonstrating the feasibility of a high luminosity 3 TeV e+-e- collider by the year 2010. One of the main issues to be demonstrated is the generation of a high average current (30 A) high frequency (12 GHz) bunched beam by means of RF manipulation. At the same time, Free Electron Lasers (FEL) are developed in several places all over the world with the aim of providing high brilliance photon sources. These machines rely on the production of high peak current electron bunches. The required performances put high demands on the diagnostic equipment and innovative longitudinal monitors have been developed during the past years. This paper gives an overview of the longitudinal instrumentation developed at ELETTRA and CTF3, where a special effort was made in order to implement at the same time non-intercepting devices for online monitoring, and destructive diagnostics which have the advantage of providing more detailed informati...

  18. A Gas-Jet Profile Monitor for the CLIC Drive Beam

    CERN Document Server

    Jeff, A; Lefevre, T; Tzoganis, V; Welsch, C P

    2013-01-01

    The Compact Linear Collider (CLIC) will use a novel acceleration scheme in which energy extracted from a very intense beam of relatively low-energy electrons (the Drive Beam) is used to accelerate a lower intensity Main Beam to very high energy. The high intensity of the Drive Beam, with pulses of more than 1015 electrons, poses a challenge for conventional profile measurements such as wire scanners. Thus, new non-invasive profile measurements are being investigated. Profile monitors using gas ionisation or fluorescence have been used at a number of accelerators. Typically, extra gas must be injected at the monitor and the rise in pressure spreads for some distance down the beam pipe. In contrast, a gas jet can be fired across the beam into a receiving chamber, with little gas escaping into the rest of the beam pipe. In addition, a gas jet shaped into a thin plane can be used like a screen on which the beam crosssectionis imaged. In this paper we present some arrangements for the generation of such a jet. In ...

  19. Jet Reconstruction and Kinematic Fitting of the Top Quark Pair Production at CLIC at √s = 3 TeV

    CERN Document Server

    Galy-Fajou, Theo; Bay, Aurelio

    Top quark physics, due to its possible link with new physics, is a critical topic now that the Standard Model has been experimentally verified. A complete method to reconstruct top quarks pairs at the proposed Compact LInear Collider project is presented here. In this study, MC generated events of e+e− → tt have been used to tune and optimize algorithms in order to reconstruct faithfully the decay products of the top quarks. An emphasis is made on the flavour identification of the jets since it is critical to identify correctly identify the jets to remove most of the background. The reconstructed jets are fitted to the topology with the KLFitter algorithms that have been adapted for CLIC. Using a multi-variable analysis, it finds the best permutation of jets with the best set of parameters using the kinematics of the event. The results of this technique applied on a sample of 49500 e+e− → tt events (corresponding to 850 fb−1 at √s = 3 TeV) is presented here.

  20. Thermal evaluation of different DC multi-conductor cable cross-sections and installation patterns for the CLIC drive-beam quadrupoles

    CERN Document Server

    Maglio, D

    2007-01-01

    The main goal of this study is to determine the thermal behaviour of different dc multi-conductor cable cross-sections and installations patterns for the CLIC drive beam quadrupoles loaded with increasing values of current intensity. A simplified two dimensional model of the heat transfer problem was prepared with a commercial CFD software, STAR-CD 4.2. The heat flux generated by Joule effect in conductors was estimated taking into account the current value per conductor and the temperature dependence of the copper electrical resistance. In parallel, a geometrical simplification of the problem has been done in order to be able to apply theoretical formulas which have been implemented by Microsoft Excel. Obtained results have been compared with those got by the dedicated software, showing between them a good correspondence for two-conductor cables and confirming, for this case, the rules given in the in the French norm NF C15-100. In case of multiconductor cables, attention is to be paid to the temperature lev...

  1. High power X-band RF test stand development and high power testing of the CLIC crab cavity

    OpenAIRE

    Woolley, Benjamin

    2015-01-01

    This thesis describes the development and operation of multiple high power X-band RF test facilities for high gradient acceleration and deflecting structures at CERN, as re-quired for the e+ e- collider research programme CLIC (Compact Linear Collider). Signif-icant improvements to the control system and operation of the first test stand, Xbox-1 are implemented. The development of the second X-band test stand at CERN, Xbox-2 is followed from inception to completion. The LLRF (Low Level Radio ...

  2. Wakefield Computations for the CLIC PETS using the Parallel Finite Element Time-Domain Code T3P

    Energy Technology Data Exchange (ETDEWEB)

    Candel, A; Kabel, A.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; /CERN

    2009-06-19

    In recent years, SLAC's Advanced Computations Department (ACD) has developed the high-performance parallel 3D electromagnetic time-domain code, T3P, for simulations of wakefields and transients in complex accelerator structures. T3P is based on advanced higher-order Finite Element methods on unstructured grids with quadratic surface approximation. Optimized for large-scale parallel processing on leadership supercomputing facilities, T3P allows simulations of realistic 3D structures with unprecedented accuracy, aiding the design of the next generation of accelerator facilities. Applications to the Compact Linear Collider (CLIC) Power Extraction and Transfer Structure (PETS) are presented.

  3. Physics potential for the measurement of σ (Hνanti ν) x BR(H → μ{sup +}μ{sup -}) at the 1.4 TeV CLIC collider

    Energy Technology Data Exchange (ETDEWEB)

    Milutinovic-Dumbelovic, G.; Bozovic-Jelisavcic, I.; Kacarevic, G.; Lukic, S.; Pandurovic, M.; Smiljanic, I. [University of Belgrade, Vinca Institute of Nuclear Sciences, Belgrade (Serbia); Grefe, C. [Universitaet Bonn, Bonn (Germany); CERN, Geneva (Switzerland); Roloff, P. [CERN, Geneva (Switzerland)

    2015-11-15

    The future compact linear collider (CLIC) offers a possibility for a rich precision physics programme, in particular in the Higgs sector through the energy staging. This is the first paper addressing the measurement of the standard model Higgs boson decay into two muons at 1.4 TeV CLIC. With respect to similar studies at future linear colliders, this paper includes several novel contributions to the statistical uncertainty of the measurement. The latter includes the equivalent photon approximation employed to describe e{sup +}e{sup -} and eγ interactions whenever the virtuality of the mediated photon is smaller than 4 GeV and realistic forward electron tagging based on energy deposition maps in the forward calorimeters, as well as several processes with the Beamstrahlung photons that results in irreducible contribution to the signal. In addition, coincidence of the Bhabha scattering with the signal and background processes is considered, altering the signal selection efficiency. The study is performed using a fully simulated CLICILD detector model. It is shown that the branching ratio for the Higgs decay into a pair of muons BR(H → μ{sup +}μ{sup -}) times the Higgs production cross-section in WW-fusion σ (Hνanti ν) can be measured with 38 % statistical accuracy at √(s) = 1.4 TeV, assuming an integrated luminosity of 1.5 ab{sup -1} with unpolarised beams. If 80 % electron beam polarisation is considered, the statistical uncertainty of the measurement is reduced to 25 %. Systematic uncertainties are negligible in comparison to the statistical uncertainty. (orig.)

  4. Analytical considerations for linear and nonlinear optimization of the TME cells. Application to the CLIC pre-damping rings

    CERN Document Server

    Fanouria, Antoniou

    2014-01-01

    The theoretical minimum emittance cells are the optimal configurations for achieving the absolute minimum emittance, if specific optics constraints are satisfied at the middle of the cell's dipole. Linear lattice design options based on an analytical approach for the theoretical minimum emittance cells are presented in this paper. In particular the parametrization of the quadrupole strengths and optics functions with respect to the emittance and drift lengths is derived. A multi-parametric space can be then created with all the cell parameters, from which one can chose any of them to be optimized. An application of this approach are finally presented for the linear and non-linear optimization of the CLIC Pre-damping rings.

  5. Alignement général du CLIC: stratégie et progrès

    CERN Document Server

    Mainaud-Durand, H

    2008-01-01

    La faisabilité concernant le pré-alignement actif du CLIC sera démontrée si l?on peut prouver qu?il existe une référence et ses capteurs associés permettant l?alignement des composants à mieux que 3 microns (1?). Pour répondre à ce challenge, une méthode de mesure d?écarts à un fil tendu est proposée, basée sur 40 ans de pratique de cette technique au CERN. Quelques problèmes demeurent concernant cette méthode : la connaissance de la forme du fil tendu utilisé comme référence droite, la détermination du géoïde à la précision souhaitée et le développement de capteurs bas coût permettant des mesures sub-micrométriques. Des études ont été entreprises afin de lever les derniers points en suspens, pendant que cette solution est intégrée dans une proposition concernant l?alignement général du CLIC. Cela implique un grand nombre d?interactions au niveau du projet, dans des domaines aussi différents que le génie civil, l?intégration, la physique du faisceau, la métrologie des �...

  6. Study and Experimental Characterization of a Novel Photo Injector for the CLIC Drive Beam

    CERN Document Server

    Mete, Oznur; Rivkin, Leonid

    2011-01-01

    Abstract In this thesis, the transverse and longitudinal beam properties of the PHIN photoinjector are characterized. The ob jective of the research is to demonstrate the reliable and stable production of a 1.3 µs long bunch train, with 2.33 nC charge per bunch and 4.5 µC of total charge, by the PHIN photoinjector. The results of this thesis are the important steps towards the feasibility demonstration of a photoinjector as the Compact Linear Collider’s drive beam source. The PHIN photoinjector has been conceptualized by a collaboration between “Laboratoire de l’Accélérateur Linéaire (LAL)”, “Rutherford Appleton Laboratory (RAL)” and “Organisation Européenne pour la Recherche Nucléaire (CERN)”. Within this collaboration, LAL and RAL have committed to the design and the construction of the RF gun and laser, respectively. The photocathode production as well as the overall coordination and commissioning were under the responsibility of CERN. The pro ject is in the framework of the second...

  7. Alignment Methods Developed for the Validation of the Thermal and Mechanical Behaviour of the Two Beam Test Modules for the CLIC Project

    CERN Document Server

    Mainaud Durand, Helene; Sosin, Mateusz; Rude, Vivien

    2014-01-01

    CLIC project will consist of more than 20 000 two meters long modules. A test setup made of three modules is being built at CERN to validate the assembly and integration of all components and technical systems and to validate the short range strategy of pre-alignment. The test setup has been installed in a room equipped with a sophisticated system of ventilation able to reproduce the environmental conditions of the CLIC tunnel. Some of the components have been equipped with electrical heaters to simulate the power dissipation, combined with a water cooling system integrated in the RF components. Using these installations, to have a better understanding of the thermal and mechanical behaviour of a module under different operation modes, machine cycles have been simulated; the misalignment of the components and their supports has been observed. This paper describes the measurements methods developed for such a project and the results obtained.

  8. Measurement of Higgs couplings and mass in e+e- collisions at CLIC in the sqrt(s) range of 350 GeV - 3 TeV

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Tomáš

    Trieste: S I S S A, 2013, s. 1-7, 295. ISSN 1824-8039. [EPS-HEP 2013 - The European Physical Society Conference on High Energy Physics 2013. Stockholm (SE), 17.07.2013- 24.07.2013] Institutional support: RVO:68378271 Keywords : Higgs boson * CLIC * CERN * Higgs branching ratios * Higgs mass * linear accelerator Subject RIV: BF - Elementary Particles and High Energy Physics http://pos.sissa.it/archive/conferences/180/295/EPS-HEP%202013_295.pdf

  9. Z Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    OpenAIRE

    A. Gutiérrez-Rodríguez; Hernández-Ruíz, M. A.

    2015-01-01

    We study the prospects of the B-L model with an additional Z′ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process e+e-→(Z,Z′)→Zh , including both the resonant and the nonresonant effects. We evaluate the total cross section of Zh and we calculate the total number of events for integrated luminosities of 500–2000 fb−1 and center of mass energies between 500 and 3000 GeV. We find t...

  10. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    CERN Document Server

    Peric,I et al.

    2013-01-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 1015 neq=cm2 , nearly 100% detection efficiency and a spatial resolution of about 3 μm were demonstrated. Since 2011 the HV detectors have first applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process.

  11. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    CERN Document Server

    Peric, Ivan; Backhaus, Malte; Barbero, Marlon; Benoit, Mathieu; Berger, Niklaus; Bompard, Frederic; Breugnon, Patrick; Clemens, Jean-Claude; Dannheim, Dominik; Dierlamm, Alexander; Feigl, Simon; Fischer, Peter; Fougeron, Denis; Garcia-Sciveres, Maurice; Heim, Timon; Hügging, Fabian; Kiehn, Moritz; Kreidl, Christian; Krüger, Hans; La Rosa, Alessandro; Liu, Jian; Lütticke, Florian; Mariñas, Carlos; Meng, Lingxin; Miucci, Antonio; Münstermann, Daniel; Nguyen, Hong Hanh; Obermann, Theresa; Pangaud, Patrick; Perrevoort, Ann-Kathrin; Rozanov, Alexandre; Schöning, André; Schwenker, Benjamin; Wiedner, Dirk

    2013-01-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 10 15 n eq = cm 2 , nearly 100% detection ef fi ciency and a spatial resolution of about 3 μ m were demonstrated. Since 2011 the HV detectors have fi rst applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process

  12. Longitudinal Beam Dynamics Studies at CTF3 And Pulse Compressor Controlling

    CERN Document Server

    Shaker, S H

    2009-01-01

    The aim of the CLIC Test Facility CTF3, built at CERN by an international collaboration, is to address the main feasibility issues of the CLIC electron-positron linear collider technology by 2010. One key-issue studied at CTF3 is the generation of the very high current drive beam, used in CLIC as the RF power source. It is particularly important to simulate and control the drive beam longitudinal dynamics in the drive beam generation complex, since it directly affects the efficiency and stability of the RF power production process. In this thesis how to use pulse compressors to achieve a high RF power in the drive beam accelerator is discussed. We also describe the ongoing effort in modelling the longitudinal evolution of the CTF3 drive beam and compare the simulations with experimental results. Our study is based on the single bunch simulation.

  13. Measurement of the branching ratios for the Standard Model Higgs decays into muon pairs and into Z boson pairs at a 1.4 TeV CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)701211; Bozovic-Jelisavcic, Ivanka; Grefe, Christian; Kacarevic, Goran; Lukic, Strahinja; Pandurovic, Mila; Roloff, Philipp Gerhard; Smiljanic, Ivan

    2016-01-01

    The measurement of the Higgs production cross-section times the branching ratios for its decays into μ+μ- and ZZ* pairs at a 1.4 TeV CLIC collider is investigated in this paper. The Standard Model Higgs boson with a mass of 126 GeV is dominantly produced via WW fusion in e+e- collisions at 1.4 TeV centre-of-mass energy. Analyses for both decay channels are based on a full simulation of the CLIC_ILD detector. All relevant physics and beam-induced background processes are taken into account. An integrated luminosity of 1.5 ab 1 and unpolarised beams are assumed. For the H-->ZZ* decay, the purely hadronic final state (ZZ*--> qq ̄qq ̄) is considered as well as ZZ* decays into two jets and two leptons (ZZ*--> qq ̄l+l- ). It is shown that the branching ratio for the Higgs decay into a muon pair times the Higgs production cross-section can be measured with 38% statistical uncertainty. It is also shown that the statistical uncertainty of the Higgs branching fraction for decay into a Z boson pair times the Hi...

  14. Brazing of Mo to a CuZr alloy for the production of bimetallic raw materials for the CLIC accelerating structures

    CERN Document Server

    Salvo, M; Heikkinen, Samuli; Salvo, Milena; Casalegno, Valentina; Sgobba, Stefano; Rizzo, Stefano; Izquierdo, Gonzalo Arnau; Taborelli, Mauro

    2010-01-01

    Future linear accelerators, as CLIC (Compact Linear Collider), are extremely demanding in terms of material properties. Traditionally accelerating structure is made of brazed OFE copper parts. For the high conducting regions submitted to mechanical fatigue, CuZr would represent an improved selection than pure copper while for regions where the highest electric field is applied a refractory metal, i.e. Mo, could result in a better performance. The feasibility of joining such materials, namely CuZr (UNS C15000) and pure Mo has been investigated. The joining method developed and investigated here consists in a vacuum brazing process exploiting a Cu-based brazing filler applied under appropriate vacuum conditions. Apparent shear strength (adapted from ASTM B898) on the joined samples was about 200 MPa. (C) 2010 Elsevier B.V. All rights reserved.

  15. A sensitiviy analysis for the stabilization of the CLIC main beam quadrupoles

    CERN Document Server

    Janssens, S; Artoos, K; Fernandez Carmona, P; Hauviller, C

    2010-01-01

    In particle colliders (like the LHC), particles are highly accelerated in a circular beam pipe before the collision. However, due to the curved trajectory of the particles, they are also loosing energy because of the so-called Bremsstrahlung. In order to bypass this fundamental limitation imposed by circular beams, the next generation of particle colliders will accelerate two straight beams of particles before the collision. One of them, the Compact Linear Collider, is currently under study at CERN. The machine is constituted of a huge number of accelerating structures (used to accelerate the particles) and quadrupoles (electromagnets used to focus the particles). The latter ones are required to be stable at the nanometer level. This extreme stability has to be guaranteed by active vibration isolation from all types of disturbances like ground vibrations, ventilation, cooling system, or acoustic noise. Because of the huge number of quadrupoles (about 4000), it is critical that the strategy adopted for the act...

  16. Two 352 MHz push pull linac pairs to generate two drive beams for CLIC multibunch operation

    International Nuclear Information System (INIS)

    The present note describes a drive beam generation scheme for multibunch operation at 1 TeV continuous mode and the luminosity of 1034 cm-2s-1. This rather conventional scheme is essentially based on acceleration with 352 MHz superconducting cavities. Contrary to a previous proposal for single bunch operation, an independent push pull linac pair per drive beam is foreseen mainly for the following reasons. Twice as many drive bunchlets per 352 MHz period halves the required charge per bunchlet. With two trains, the bunchlet deceleration variation inside one train is reduced. A good drive beam to RF efficiencies are obtained through matching of the train energy profile to the decelerating wake pattern in the drive linac. The reduced wake variation makes it feasible to preshape the train energy profile to the required ramp by simple phase shifting of the 352 MHz voltage in the superconducting cavities in conjunction with a small harmonics correction. The layout of the system consists of the 30 GHz accelerating structures, 30 GHz transfer structures, fourth harmonics (1408 MHz) superconducting structures, push pull fundamental (352 MHz) linac pair and switch yards. Emphasis has been put on wall-plug to main beam efficiency and minimum capital cost to the extent possible for the concept chosen. The issues of studies are harmonic synthesis of an optimum acceleration ramp, beam loading compensation for fundamental frequency cavities, acceleration of 22 bunchlets, fourth harmonic cavities, wall plug to main beam efficiency and RF deflectors. The main disadvantage of the scheme seem to be: a) high bunchlet charge of 45 n C. b) overall efficiency of only 10.1%, essentially because of the limited stored RF energy in the 352 MHz structures, which limits the number of drive bunchlet trains per pulse. c) significant amount of RF and cryogenics hardware for complete drive beam generation complex. The main advantage appears to be: a) no long drive beam transport lines, no 180 and

  17. Beam instability induced by rf deflectors in the combiner ring of the CLIC test facility and mitigation by damped deflecting structures

    CERN Document Server

    Alesini, D; Biscari, C; Ghigo, A; Corsini, R

    2011-01-01

    In the CTF3 (CLIC test facility 3) run of November 2007, a vertical beam instability has been found in the combiner ring during operation. After a careful analysis, the source of the instability has been identified in the vertical deflecting modes trapped in the rf deflectors and excited by the beam passage. A dedicated tracking code that includes the induced transverse wakefield and the multibunch multipassage effects has been written and the results of the beam dynamics analysis are presented in the paper. The mechanism of the instability was similar to the beam breakup in a linear accelerator or in an energy recovery linac. The results of the code allowed identifying the main key parameters driving such instability and allowed finding the main knobs to mitigate it. To completely suppress such beam instability, two new rf deflectors have been designed, constructed, and installed in the ring. In the new structures the frequency separation between the vertical and horizontal deflecting modes has been increase...

  18. Breast density quantification using magnetic resonance imaging (MRI) with bias field correction: A postmortem study

    International Nuclear Information System (INIS)

    Purpose: Quantification of breast density based on three-dimensional breast MRI may provide useful information for the early detection of breast cancer. However, the field inhomogeneity can severely challenge the computerized image segmentation process. In this work, the effect of the bias field in breast density quantification has been investigated with a postmortem study. Methods: T1-weighted images of 20 pairs of postmortem breasts were acquired on a 1.5 T breast MRI scanner. Two computer-assisted algorithms were used to quantify the volumetric breast density. First, standard fuzzy c-means (FCM) clustering was used on raw images with the bias field present. Then, the coherent local intensity clustering (CLIC) method estimated and corrected the bias field during the iterative tissue segmentation process. Finally, FCM clustering was performed on the bias-field-corrected images produced by CLIC method. The left–right correlation for breasts in the same pair was studied for both segmentation algorithms to evaluate the precision of the tissue classification. Finally, the breast densities measured with the three methods were compared to the gold standard tissue compositions obtained from chemical analysis. The linear correlation coefficient, Pearson'sr, was used to evaluate the two image segmentation algorithms and the effect of bias field. Results: The CLIC method successfully corrected the intensity inhomogeneity induced by the bias field. In left–right comparisons, the CLIC method significantly improved the slope and the correlation coefficient of the linear fitting for the glandular volume estimation. The left–right breast density correlation was also increased from 0.93 to 0.98. When compared with the percent fibroglandular volume (%FGV) from chemical analysis, results after bias field correction from both the CLIC the FCM algorithms showed improved linear correlation. As a result, the Pearson'sr increased from 0.86 to 0.92 with the bias field correction

  19. Signature of MoU between CERN and Australian Collaboration for Accelerator Science (ACAS); Roger Rassool, ACAS Director; Mark Boland, ACAS Deputy Director; Jean-Pierre Delahaye, CLIC Project Leader; in the presence of Rolf Heuer, Director-General and Emmanuel Tsesmelis, Adviser for Australia

    CERN Multimedia

    Maximilien Brice

    2010-01-01

    Signature of MoU between CERN and Australian Collaboration for Accelerator Science (ACAS); Roger Rassool, ACAS Director; Mark Boland, ACAS Deputy Director; Jean-Pierre Delahaye, CLIC Project Leader; in the presence of Rolf Heuer, Director-General and Emmanuel Tsesmelis, Adviser for Australia

  20. C. Petrone et al.: "Magnetic measurement of the model magnet QD0 designed for the CLIC final focus beam transport line." CERN TE-MSC Internal Note, EDMS Nr: 1184196

    CERN Document Server

    Arpaia, Pasquale; Petrone, Carlo; Russenschuck, Stephan; Walckiers, Louis

    2012-01-01

    This note presents the results of the magnetic measurements performed on QD0, model magnet for the final focus transport line for CLIC (Fig. 1). This high-gradient, hybrid quadrupole has a yoke length of 0.1 m and an aperture of 8.3 mm. ND2Fe14B Permanent magnet blocks provide a gradient of 150 T/m, which can be further increased to 530 T/m when the four coils are excited to 18.3 A. The request was to measure the strength of the field and the multipole coefficients at different currents. The measurement of the field strength, by means of the single stretched wire system, was done in December 2011 in the I8 laboratory. The measurement of the multipole was done by means of the oscillating wire system [1][2].

  1. Possible Cryogenic Configurations for the Superconducting Magnets of the Damping Rings of the Compact Linear Collider (CLIC)

    CERN Document Server

    Perin, A; Russenschuck, S; Schoerling, D

    2012-01-01

    The Compact Linear Collider is a future electron-positron linear collider currently under study. Before being injected into the main linear accelerating structures, both the electron and the positron beams must pass through damping rings that will drastically reduce their emittance in all three dimensions. The required emittance reduction is achieved by passing the particle beams through alternating magnetic fields in superconducting wiggler magnets that result in the emission of intense synchrotron radiation. This article describes possible cooling schemes and possible cryogenic configurations to keep the magnets at operating temperature while removing the heat generated by the synchrotron radiation.

  2. Positron source investigation by using CLIC drive beam for Linac-LHC based e+p collider

    Science.gov (United States)

    Arιkan, Ertan; Aksakal, Hüsnü

    2012-08-01

    Three different methods which are alternately conventional, Compton backscattering and Undulator based methods employed for the production of positrons. The positrons to be used for e+p collisions in a Linac-LHC (Large Hadron Collider) based collider have been studied. The number of produced positrons as a function of drive beam energy and optimum target thickness has been determined. Three different targets have been used as a source investigation which are W75-Ir25, W75-Ta25, and W75-Re25 for three methods. Estimated number of the positrons has been performed with FLUKA simulation code. Then, these produced positrons are used for following Adiabatic matching device (AMD) and capture efficiency is determined. Then e+p collider luminosity corresponding to the methods mentioned above have been calculated by CAIN code.

  3. 6th July 2010 - United Kingdom Science and Technology Facilities Council W. Whitehorn signing the guest book with Head of International relations F. Pauss, visiting the Computing Centre with Information Technology Department Head Deputy D. Foster, the LHC superconducting magnet test hall with Technology Department P. Strubin,the Centre Control Centre with Operation Group Leader M. Lamont and the CLIC/CTF3 facility with Project Leader J.-P. Delahaye.

    CERN Multimedia

    Teams : M. Brice, JC Gadmer

    2010-01-01

    6th July 2010 - United Kingdom Science and Technology Facilities Council W. Whitehorn signing the guest book with Head of International relations F. Pauss, visiting the Computing Centre with Information Technology Department Head Deputy D. Foster, the LHC superconducting magnet test hall with Technology Department P. Strubin,the Centre Control Centre with Operation Group Leader M. Lamont and the CLIC/CTF3 facility with Project Leader J.-P. Delahaye.

  4. X-ray Photoemission Spectroscopy Studies of Cesium Antimonide Photocathodes for Photoinjector Applications

    Science.gov (United States)

    Martini, Irene; Chevallay, Eric; Fedosseev, Valentin; Hessler, Christoph; Neupert, Holger; Nistor, Valentin; Taborelli, Mauro

    Within the CLIC (Compact Linear Collider) project, feasibility studies of a photoinjector option for the drive beam as an alternative to its baseline design using a thermionic electron gun (Geschonke et al. [1]) are on-going. This R&D program covers both the laser and the photocathode side. Cesium antimonide cathodes were produced at CERN by co-deposition onto copper substrates and characterized by photoemission and by XPS (X-ray Photoemission Spectroscopy) analysis. A systematic study on newly produced and used photocathodes was conducted in order to correlate the surface composition to the photoemissive properties.

  5. Study of vibrations and stabilization of linear collider final doublets at the sub-nanometer scale

    International Nuclear Information System (INIS)

    CLIC is one of the current projects of high energy linear colliders. Vertical beam sizes of 0.7 nm at the time of the collision and fast ground motion of a few nanometers impose an active stabilization of the final doublets at a fifth of nanometer above 4 Hz. The majority of my work concerned vibrations and active stabilization study of cantilever and slim beams in order to be representative of the final doublets of CLIC. In a first part, measured performances of different types of vibration sensors associated to an appropriate instrumentation showed that accurate measurements of ground motion are possible from 0.1 Hz up to 2000 Hz on a quiet site. Also, electrochemical sensors answering a priori the specifications of CLIC can be incorporated in the active stabilization at a fifth of nanometer. In a second part, an experimental and numerical study of beam vibrations enabled to validate the efficiency of the numerical prediction incorporated then in the simulation of the active stabilization. Also, a study of the impact of ground motion and of acoustic noise on beam vibrations showed that an active stabilization is necessary at least up to 1000 Hz. In a third part, results on the active stabilization of a beam at its two first resonances are shown down to amplitudes of a tenth of nanometer above 4 Hz by using in parallel a commercial system performing passive and active stabilization of the clamping. The last part is related to a study of a support for the final doublets of a linear collider prototype in phase of finalization, the ATF2 prototype. This work showed that relative motion between this support and the ground is below imposed tolerances (6 nm above 0.1 Hz) with appropriate boundary conditions. (author)

  6. RF Breakdown Studies in Tungsten and Copper Structures

    Science.gov (United States)

    Laurent, L.; Adolphsen, C.; Beebe, S.; Döbert, S.; Luhmann, N. C.; Pearson, C.; Rodriguez, J. A.; Scheitrum, G.; Wuensch, W.

    2006-11-01

    This paper reports on experimental results from the SLAC NLC accelerator structure closeout program, and discusses a study that was conducted to improve the smoothness of machined tungsten for use in high gradient structures. At the Next Linear Collider Test Accelerator (NLCTA), an X-band (11.424 GHz) structure was operated at a lower temperature to determine whether this would decrease the low rate of breakdowns that still occur after initial processing. Also, various vacuum venting experiments were performed to determine the impact of air, airborne particulates, and oxidation on the performance of a processed accelerator structure. As part of a more long-range high-gradient structure development program, alternative materials to copper are being explored. The CLIC study group at CERN has conducted several accelerator experiments at 30 GHz with structures that have tungsten and molybdenum iris inserts. SLAC has also tested versions of the CLIC 30 GHz design scaled to 11.424 GHz. The results have prompted a tungsten material study directed at exploring new fabrication processes that would provide a cleaner and smoother tungsten surface topography suitable for high gradient applications. A significantly improved tungsten surface finish resulted from this material study, and a single cell X-band cavity containing noses with such tungsten surfaces will be high power tested soon.

  7. Linear collider studies in Europe

    International Nuclear Information System (INIS)

    In an early phase of work on linear colliders in Europe the main emphasis was put on new methods of acceleration at very high gradient. Substantial research and development work originating in this early period are the wake field acceleration pursued at DESY, the plasma beat wave experiments carried out at the Rutherford Laboratory and Imperial College and the switched power linac proposal leading to experimental work at BNL and CERN. Also originating in this period but already concerned with RF acceleration is the development of lasertrons at LAL Orsay. In a later phase, when it was fully realized that the main problem was the generation of adequate luminosity and the fundamental constraints on the choice of parameters were better understood the emphasis shifted back to radio-frequency acceleration, classical in principle but not at all in the choice of parameters and technologies required here. This is certainly true for the study of a CERN Linear Collider (CLIC). It is also true for DESY where a Resonant Wake Field Transformer - a string of RF cavities excited by a ring-shaped drive bunch - is being proposed following the successful completion of the first round of experiments in the original Wake Field Transformer set-up. The work for CLIC - centered at CERN but carried out in collaboration with other European laboratories and ECFA - aims at paving the way for an actual project and attempts, therefore, to cover all fundamental aspects of a linear e+e- collider. For this reason the present paper is mainly based on this work

  8. Study of vibrations and stabilization of linear collider final doublets at the sub-nanometer scale; Etude des vibrations et de la stabilisation a l'echelle sous-nanometrique des doublets finaux d'un collisionneur lineaire

    Energy Technology Data Exchange (ETDEWEB)

    Bolzon, B

    2007-11-15

    CLIC is one of the current projects of high energy linear colliders. Vertical beam sizes of 0.7 nm at the time of the collision and fast ground motion of a few nanometers impose an active stabilization of the final doublets at a fifth of nanometer above 4 Hz. The majority of my work concerned vibrations and active stabilization study of cantilever and slim beams in order to be representative of the final doublets of CLIC. In a first part, measured performances of different types of vibration sensors associated to an appropriate instrumentation showed that accurate measurements of ground motion are possible from 0.1 Hz up to 2000 Hz on a quiet site. Also, electrochemical sensors answering a priori the specifications of CLIC can be incorporated in the active stabilization at a fifth of nanometer. In a second part, an experimental and numerical study of beam vibrations enabled to validate the efficiency of the numerical prediction incorporated then in the simulation of the active stabilization. Also, a study of the impact of ground motion and of acoustic noise on beam vibrations showed that an active stabilization is necessary at least up to 1000 Hz. In a third part, results on the active stabilization of a beam at its two first resonances are shown down to amplitudes of a tenth of nanometer above 4 Hz by using in parallel a commercial system performing passive and active stabilization of the clamping. The last part is related to a study of a support for the final doublets of a linear collider prototype in phase of finalization, the ATF2 prototype. This work showed that relative motion between this support and the ground is below imposed tolerances (6 nm above 0.1 Hz) with appropriate boundary conditions. (author)

  9. Higgs Working Group Report of the Snowmass 2013 Community Planning Study

    CERN Document Server

    Dawson, S; Logan, H; Qian, J; Tully, C; Van Kooten, R; Ajaib, A; Anastassov, A; Anderson, I; Bake, O; Barger, V; Barklow, T; Batell, B; Battaglia, M; Berge, S; Blondel, A; Bolognesi, S; Brau, J; Brownson, E; Cahill-Rowley, M; Calancha-Paredes, C; Chen, C -Y; Chou, W; Clare, R; Cline, D; Craig, N; Cranmer, K; de Gruttola, M; Elagin, A; Essig, R; Everett, L; Feng, E; Fujii, K; Gainer, J; Gao, Y; Gogoladze, I; Gori, S; Goncalo, R; Graf, N; Grojean, C; Guindon, S; Han, T; Hanson, G; Harnik, R; Heinemann, B; Heinemeyer, S; Heintz, U; Hewett, J; Ilchenko, Y; Ismail, A; Jain, V; Janot, P; Kawada, S; Kehoe, R; Klute, M; Kotwal, A; Krueger, K; Kukartsev, G; Kumar, K; Kunkle, J; Lewis, I; Li, Y; Linssen, L; Lipeles, E; Lipton, R; Liss, T; List, J; Liu, T; Liu, Z; Low, I; Ma, T; Mackenzie, P; Mellado, B; Melnikov, K; Moortgat-Pick, G; Mourou, G; Narain, M; Nielsen, J; Okada, N; Okawa, H; Olsen, J; Onyisi, P; Parashar, N; Peskin, M; Petriello, F; Plehn, T; Pollard, C; Potter, C; Prokofiev, K; Rauch, M; Rizzo, T; Robens, T; Rodriguez, V; Roloff, P; Ruiz, R; Sanz, V; Sayre, J; Shafi, Q; Shaughnessy, G; Sher, M; Simon, F; Solyak, N; Stupak, J; Su, S; Tanabe, T; Tajima, T; Telnov, V; Tian, J; Thomas, S; Thomson, M; Un, C; Velasco, M; Wagner, C; Wang, S; Whitbeck, A; Yao, W; Yokoya, H; Zenz, S; Zerwas, D; Zhang, Y; Zhou, Y

    2013-01-01

    This report summarizes the work of the Energy Frontier Higgs Boson working group of the 2013 Community Summer Study (Snowmass). We identify the key elements of a precision Higgs physics program and document the physics potential of future experimental facilities as elucidated during the Snowmass study. We study Higgs couplings to gauge boson and fermion pairs, double Higgs production for the Higgs self-coupling, its quantum numbers and $C\\!P$-mixing in Higgs couplings, the Higgs mass and total width, and prospects for direct searches for additional Higgs bosons in extensions of the Standard Model. Our report includes projections of measurement capabilities from detailed studies of the Compact Linear Collider (CLIC), a Gamma-Gamma Collider, the International Linear Collider (ILC), the Large Hadron Collider High-Luminosity Upgrade (HL-LHC), Very Large Hadron Colliders up to 100 TeV (VLHC), a Muon Collider, and a Triple-Large Electron Positron Collider (TLEP).

  10. A computational study of dielectric photonic-crystal-based accelerator cavities

    Science.gov (United States)

    Bauer, C. A.

    Future particle accelerator cavities may use dielectric photonic crystals to reduce harmful wakefields and increase the accelerating electric field (or gradient). Reduced wakefields are predicted based on the bandgap property of some photonic crystals (i.e. frequency-selective reflection/transmission). Larger accelerating gradients are predicted based on certain dielectrics' strong resistance to electrical breakdown. Using computation, this thesis investigated a hybrid design of a 2D sapphire photonic crystal and traditional copper conducting cavity. The goals were to test the claim of reduced wakefields and, in general, judge the effectiveness of such structures as practical accelerating cavities. In the process, we discovered the following: (1) resonant cavities in truncated photonic crystals may confine radiation weakly compared to conducting cavities (depending on the level of truncation); however, confinement can be dramatically increased through optimizations that break lattice symmetry (but retain certain rotational symmetries); (2) photonic crystal cavities do not ideally reduce wakefields; using band structure calculations, we found that wakefields are increased by flat portions of the frequency dispersion (where the waves have vanishing group velocities). A complete comparison was drawn between the proposed photonic crystal cavities and the copper cavities for the Compact Linear Collider (CLIC); CLIC is one of the candidates for a future high-energy electron-positron collider that will study in greater detail the physics learned at the Large Hadron Collider. We found that the photonic crystal cavity, when compared to the CLIC cavity: (1) can lower maximum surface magnetic fields on conductors (growing evidence suggests this limits accelerating gradients by inducing electrical breakdown); (2) shows increased transverse dipole wakefields but decreased longitudinal monopole wakefields; and (3) exhibits lower accelerating efficiencies (unless a large photonic

  11. The study of the photon structure function at the ILC energy range

    CERN Document Server

    Krupa, B; Zawiejski, L

    2015-01-01

    At the future $e^{+}e^{-}$ linear collider ILC/CLIC it will be able to measure the photon structure functions in a wider range of kinematic variables x and $Q^{2}$ in comparison to the previous results of experiments at LEP. The classical way to measure the photon structure functions is the study of $e^{+}e^{-} \\rightarrow e^{+}e^{-} {\\gamma}{\\gamma} \\rightarrow e^{+}e^{-}$ X process, where X is the leptonic or hadronic final state. For the study of the QED and hadronic photon structure functions the simulations of two-photon processes were performed at the ILC center-of-mass energy equal to 500 GeV using the PYTHIA and the ILCSoft package. The analysis used information related to the forward detectors, tracking detectors and calorimeters which are parts of the ILD detector concept.

  12. Now entering phase two...

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    Building on the success of their feasibility phase, the CLIC test facility, CTF3, has just launched into a five-year project development phase. This will involve detailed performance optimisation studies, marking the project’s transition from pure research and development to prototyping and construction.   CLIC accelerator modules under construction at CERN. “With the feasibility phase now complete, we have established that CLIC can be built,” says Roberto Corsini, CLIC Collaboration spokesperson. “Now we want to be sure that it can provide the luminosity and energy performance needed. We will be looking at the engineering, performance and cost of a real CLIC machine also seeing if we can reduce it.” CTF3’s second phase will focus on selected performance-related research areas for further investigation. The largest of these involves the construction and testing of several authentic CLIC accelerator modules that are currently being ...

  13. Influence of sinomenine on protein profiles of peripheral blood mononuclear cells from ankylosing spondylitis patients: a pharmacoproteomics study

    Institute of Scientific and Technical Information of China (English)

    HUANG Zhi-xiang; TAN Jin-hui; LI Tian-wang; DENG Wei-ming; QIU Ke-wei; LIAO Ze-tao; ZENG Zhao-qiu

    2013-01-01

    Background Ankylosing spondylitis (AS) is a common inflammatory rheumatic disease which lacks satisfactory treatment so far.Sinomenine (SIN) is an alkaloid and has recently been utilized in treating multiple rheumatic diseases including AS in China,but its exact mechanism remains to be explored.This study investigated the alteration of proteome in peripheral blood mononuclear cells (PBMCs) from AS patients.Methods Thirty AS patients were enrolled in this study.PBMCs from each AS patient were cultured in medium with or without SIN respectively.Then PBMCs proteins from both groups were separated by two-dimensional electrophoresis (2-DE) and analyzed by mass spectrometry (MS).Two differentially expressed proteins were then chosen to be verified using Western blotting.Results Seven proteins,including α-synuclein (SNCA),calmodulin (CALM),acidic leucine-rich nuclear phosphoprotein 32 family member A (ANP32A),chloride intracellular channel protein 1 (CLIC1),guanine nucleotide-binding protein G(I)/G(S)/ G(T) subunit beta-1 (GNB1),gelsolin (GSN) and histone H2B type 1-M (HISTH2BM)were over-expressed,while coronin1A (CORO1A) was under-expressed in the SIN-treated PBMCs.Further bioinformatics search indicated that the changes of SNCA,ANP32A and CLIC1 pertained to apoptosis,while changes of GSN and CORO1A were associated with both apoptosis and inhibition of immunological function.Subsequently GSN and CORO1A were selected to validate by Western blotting and the results were consistent with those of 2-DE.Conclusion There were 8 differentially expressed proteins in the SIN-treated PBMCs,which might shed some light on the mechanism of SIN in the treatment of AS.

  14. Simulation of the CLIC transfer structure by means of MAFIA

    Science.gov (United States)

    Millich, Antonio

    1993-12-01

    The function of the CTS is to extract 30 GHz power from the drive beam and to make it available for the acceleration of the main beam. The simulation of a six cells section of the CTS using the MAFIA set of codes has provided the designers of the structure with a set of RF parameters at 30 GHz. The frequency domain analysis has allowed the plotting of the dispersion curves for the first few pass bands, whereas the time domain analysis has provided results on the shape and magnitude of the longitudinal and transverse wake fields and of the loss factors.

  15. An Experimental Approach to Simulations of the CLIC Interaction Point

    DEFF Research Database (Denmark)

    Esberg, Jakob

    2012-01-01

    respect to the luminosity weighted depolarization is discussed. In the chapter on muons, the implementation of the production of incoherent muons in GUINEA-PIG++ will be discussed. Comments on the correctness and completeness of the implementation of muon production will be presented. The chapter on...

  16. CLICing into action

    CERN Multimedia

    Barbara Warmbein

    2015-01-01

    Putting its acronym into action, the Compact Linear Collider (CLIC) collaboration is testing its first compact accelerator module in the CTF3 test facility. Fed by high-power waveguides, cables and cooling tubes, the module has all the functions of future CLIC modules and allows the experts to test all the features, including frequency, losses, damping, acceleration and deceleration.   The new CLIC module in the CTF3 test facility. CLIC is one of the potential follow-up projects to the LHC, alongside the International Linear Collider (ILC) and the Future Circular Collider (FCC) studies. Instead of smashing protons into protons, it is designed to collide electrons with positrons. Following the publication of its CDR in 2012, the CLIC collaboration entered the project preparation phase - testing its unique technology, making improvements and taking a closer look at the cost of the individual components. This is where the new module comes in. While many of the techniques and technologies neede...

  17. Event-shape of dileptons plus missing energy at a linear collider as a supersymmetry/Arkani-Hamed-Dimopoulos-Dvali discriminant

    Indian Academy of Sciences (India)

    Pabir Roy

    2007-11-01

    An event-shape analysis of the dileptons in the process + - → ℓ+ ℓ- Ɇ, studied in ILC or CLIC, can clearly discriminate between a supersymmetric or a large extra dimensional (ADD) production mechanism.

  18. Prof. John Wood, Chief Executive Designate, Dr Gordon Walker, Directorate, Chief Executive, Prof. Ken J. Peach, Head of the Particle Physics Department, CLRC Rutherford Appleton Laboratory, United Kingdom

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    L. to. r.: Dr. Ian Wilson, CLIC Deputy Study Leader, Prof. Ken J. Peach, Head of the Particle Physics Department, Prof. John Wood, Chief Executive Designate, Dr. Gordon Walker, Directorate, Chief Executive

  19. Comparative Studies of High-Gradient Rf and Dc Breakdowns

    CERN Document Server

    Kovermann, Jan Wilhelm; Wuensch, Walter

    2010-01-01

    The CLIC project is based on normal-conducting high-gradient accelerating structures with an average accelerating gradient of 100 MV/m. The maximum achievable gradient in these structures is limited by the breakdown phenomenon. The physics of breakdowns is not yet fully understood quantitatively. A full knowledge could have strong impact on the design, material choice and construction of rf structures. Therefore, understanding breakdowns has great importance to reaching a gradient of 100MV/m with an acceptable breakdown probability. This thesis addresses the physics underlying the breakdown effect, focusing on a comparison of breakdowns in rf structures and in a dc spark setup. The dc system is simpler, easier to benchmark against simulations, with a faster turnaround time, but the relationship to rf breakdown must be established. To do so, an experimental approach based on optical diagnostics and electrical measurements methods was made. Following an introduction into the CLIC project, a general theoretical ...

  20. Updated baseline for a staged Compact Linear Collider

    CERN Document Server

    Boland, M J; Giansiracusa, P J; Lucas, T G; Rassool, R P; Balazs, C; Charles, T K; Afanaciev, K; Emeliantchik, I; Ignatenko, A; Makarenko, V; Shumeiko, N; Patapenka, A; Zhuk, I; Abusleme Hoffman, A C; Diaz Gutierrez, M A; Gonzalez, M Vogel; Chi, Y; He, X; Pei, G; Pei, S; Shu, G; Wang, X; Zhang, J; Zhao, F; Zhou, Z; Chen, H; Gao, Y; Huang, W; Kuang, Y P; Li, B; Li, Y; Shao, J; Shi, J; Tang, C; Wu, X; Ma, L; Han, Y; Fang, W; Gu, Q; Huang, D; Huang, X; Tan, J; Wang, Z; Zhao, Z; Laštovička, T; Uggerhoj, U; Wistisen, T N; Aabloo, A; Eimre, K; Kuppart, K; Vigonski, S; Zadin, V; Aicheler, M; Baibuz, E; Brücken, E; Djurabekova, F; Eerola, P; Garcia, F; Haeggström, E; Huitu, K; Jansson, V; Karimaki, V; Kassamakov, I; Kyritsakis, A; Lehti, S; Meriläinen, A; Montonen, R; Niinikoski, T; Nordlund, K; Österberg, K; Parekh, M; Törnqvist, N A; Väinölä, J; Veske, M; Farabolini, W; Mollard, A; Napoly, O; Peauger, F; Plouin, J; Bambade, P; Chaikovska, I; Chehab, R; Davier, M; Kaabi, W; Kou, E; LeDiberder, F; Pöschl, R; Zerwas, D; Aimard, B; Balik, G; Baud, J-P; Blaising, J-J; Brunetti, L; Chefdeville, M; Drancourt, C; Geoffroy, N; Jacquemier, J; Jeremie, A; Karyotakis, Y; Nappa, J M; Vilalte, S; Vouters, G; Bernard, A; Peric, I; Gabriel, M; Simon, F; Szalay, M; van der Kolk, N; Alexopoulos, T; Gazis, E N; Gazis, N; Ikarios, E; Kostopoulos, V; Kourkoulis, S; Gupta, P D; Shrivastava, P; Arfaei, H; Dayyani, M K; Ghasem, H; Hajari, S S; Shaker, H; Ashkenazy, Y; Abramowicz, H; Benhammou, Y; Borysov, O; Kananov, S; Levy, A; Levy, I; Rosenblat, O; D'Auria, G; Di Mitri, S; Abe, T; Aryshev, A; Higo, T; Makida, Y; Matsumoto, S; Shidara, T; Takatomi, T; Takubo, Y; Tauchi, T; Toge, N; Ueno, K; Urakawa, J; Yamamoto, A; Yamanaka, M; Raboanary, R; Hart, R; van der Graaf, H; Eigen, G; Zalieckas, J; Adli, E; Lillestøl, R; Malina, L; Pfingstner, J; Sjobak, K N; Ahmed, W; Asghar, M I; Hoorani, H; Bugiel, S; Dasgupta, R; Firlej, M; Fiutowski, T A; Idzik, M; Kopec, M; Kuczynska, M; Moron, J; Swientek, K P; Daniluk, W; Krupa, B; Kucharczyk, M; Lesiak, T; Moszczynski, A; Pawlik, B; Sopicki, P; Wojtoń, T; Zawiejski, L; Kalinowski, J; Krawczyk, M; Żarnecki, A F; Firu, E; Ghenescu, V; Neagu, A T; Preda, T; Zgura, I-S; Aloev, A; Azaryan, N; Budagov, J; Chizhov, M; Filippova, M; Glagolev, V; Gongadze, A; Grigoryan, S; Gudkov, D; Karjavine, V; Lyablin, M; Olyunin, A; Samochkine, A; Sapronov, A; Shirkov, G; Soldatov, V; Solodko, A; Solodko, E; Trubnikov, G; Tyapkin, I; Uzhinsky, V; Vorozhtov, A; Levichev, E; Mezentsev, N; Piminov, P; Shatilov, D; Vobly, P; Zolotarev, K; Bozovic-Jelisavcic, I; Kacarevic, G; Lukic, S; Milutinovic-Dumbelovic, G; Pandurovic, M; Iriso, U; Perez, F; Pont, M; Trenado, J; Aguilar-Benitez, M; Calero, J; Garcia-Tabares, L; Gavela, D; Gutierrez, J L; Lopez, D; Toral, F; Moya, D; Ruiz-Jimeno, A; Vila, I; Argyropoulos, T; Gutierrez, C Blanch; Boronat, M; Esperante, D; Faus-Golfe, A; Fuster, J; Fuster Martinez, N; Galindo Muñoz, N; García, I; Giner Navarro, J; Ros, E; Vos, M; Brenner, R; Ekelöf, T; Jacewicz, M; Ögren, J; Olvegård, M; Ruber, R; Ziemann, V; Aguglia, D; Alipour Tehrani, N; Aloev, A; Andersson, A; Andrianala, F; Antoniou, F; Artoos, K; Atieh, S; Ballabriga Sune, R; Barnes, M J; Barranco Garcia, J; Bartosik, H; Belver-Aguilar, C; Benot Morell, A; Bett, D R; Bettoni, S; Blanchot, G; Blanco Garcia, O; Bonnin, X A; Brunner, O; Burkhardt, H; Calatroni, S; Campbell, M; Catalan Lasheras, N; Cerqueira Bastos, M; Cherif, A; Chevallay, E; Constance, B; Corsini, R; Cure, B; Curt, S; Dalena, B; Dannheim, D; De Michele, G; De Oliveira, L; Deelen, N; Delahaye, J P; Dobers, T; Doebert, S; Draper, M; Duarte Ramos, F; Dubrovskiy, A; Elsener, K; Esberg, J; Esposito, M; Fedosseev, V; Ferracin, P; Fiergolski, A; Foraz, K; Fowler, A; Friebel, F; Fuchs, J-F; Fuentes Rojas, C A; Gaddi, A; Garcia Fajardo, L; Garcia Morales, H; Garion, C; Gatignon, L; Gayde, J-C; Gerwig, H; Goldblatt, A N; Grefe, C; Grudiev, A; Guillot-Vignot, F G; Gutt-Mostowy, M L; Hauschild, M; Hessler, C; Holma, J K; Holzer, E; Hourican, M; Hynds, D; Inntjore Levinsen, Y; Jeanneret, B; Jensen, E; Jonker, M; Kastriotou, M; Kemppinen, J M K; Kieffer, R B; Klempt, W; Kononenko, O; Korsback, A; Koukovini Platia, E; Kovermann, J W; Kozsar, C-I; Kremastiotis, I; Kulis, S; Latina, A; Leaux, F; Lebrun, P; Lefevre, T; Linssen, L; Llopart Cudie, X; Maier, A A; Mainaud Durand, H; Manosperti, E; Marelli, C; Marin Lacoma, E; Martin, R; Mazzoni, S; Mcmonagle, G; Mete, O; Mether, L M; Modena, M; Münker, R M; Muranaka, T; Nebot Del Busto, E; Nikiforou, N; Nisbet, D; Nonglaton, J-M; Nuiry, F X; Nürnberg, A; Olvegard, M; Osborne, J; Papadopoulou, S; Papaphilippou, Y; Passarelli, A; Patecki, M; Pazdera, L; Pellegrini, D; Pepitone, K; Perez, F; Perez Codina, E; Perez Fontenla, A; Persson, T H B; Petrič, M; Pitters, F

    2016-01-01

    The Compact Linear Collider (CLIC) is a multi-TeV high-luminosity linear e+e- collider under development. For an optimal exploitation of its physics potential, CLIC is foreseen to be built and operated in a staged approach with three centre-of-mass energy stages ranging from a few hundred GeV up to 3 TeV. The first stage will focus on precision Standard Model physics, in particular Higgs and top-quark measurements. Subsequent stages will focus on measurements of rare Higgs processes, as well as searches for new physics processes and precision measurements of new states, e.g. states previously discovered at LHC or at CLIC itself. In the 2012 CLIC Conceptual Design Report, a fully optimised 3 TeV collider was presented, while the proposed lower energy stages were not studied to the same level of detail. This report presents an updated baseline staging scenario for CLIC. The scenario is the result of a comprehensive study addressing the performance, cost and power of the CLIC accelerator complex as a function of...

  1. Top quark threshold scan and study of detectors for highly granular hadron calorimeters at future linear colliders

    International Nuclear Information System (INIS)

    Two major projects for future linear electron-positron colliders, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC), are currently under development. These projects can be seen as complementary machines to the Large Hadron Collider (LHC) which permit a further progress in high energy physics research. They overlap considerably and share the same technological approaches. To meet the ambitious goals of precise measurements, new detector concepts like very finely segmented calorimeters are required. We study the precision of the top quark mass measurement achievable at CLIC and the ILC. The employed method was a t anti t pair production threshold scan. In this technique, simulated measurement points of the t anti t production cross section around the threshold are fitted with theoretical curves calculated at next-to-next-to-leading order. Detector effects, the influence of the beam energy spectrum and initial state radiation of the colliding particles are taken into account. Assuming total integrated luminosity of 100 fb-1, our results show that the top quark mass in a theoretically well-defined 1S mass scheme can be extracted with a combined statistical and systematic uncertainty of less than 50 MeV. The other part of this work regards experimental studies of highly granular hadron calorimeter (HCAL) elements. To meet the required high jet energy resolution at the future linear colliders, a large and finely segmented detector is needed. One option is to assemble a sandwich calorimeter out of many low-cost scintillators read out by silicon photomultipliers (SiPM). We characterize the areal homogeneity of SiPM response with the help of a highly collimated beam of pulsed visible light. The spatial resolution of the experiment reach the order of 1 μm and allows to study the active area structures within single SiPM microcells. Several SiPM models are characterized in terms of relative photon detection efficiency and probability crosstalk at

  2. Top quark threshold scan and study of detectors for highly granular hadron calorimeters at future linear colliders

    Energy Technology Data Exchange (ETDEWEB)

    Tesar, Michal

    2014-03-11

    Two major projects for future linear electron-positron colliders, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC), are currently under development. These projects can be seen as complementary machines to the Large Hadron Collider (LHC) which permit a further progress in high energy physics research. They overlap considerably and share the same technological approaches. To meet the ambitious goals of precise measurements, new detector concepts like very finely segmented calorimeters are required. We study the precision of the top quark mass measurement achievable at CLIC and the ILC. The employed method was a t anti t pair production threshold scan. In this technique, simulated measurement points of the t anti t production cross section around the threshold are fitted with theoretical curves calculated at next-to-next-to-leading order. Detector effects, the influence of the beam energy spectrum and initial state radiation of the colliding particles are taken into account. Assuming total integrated luminosity of 100 fb{sup -1}, our results show that the top quark mass in a theoretically well-defined 1S mass scheme can be extracted with a combined statistical and systematic uncertainty of less than 50 MeV. The other part of this work regards experimental studies of highly granular hadron calorimeter (HCAL) elements. To meet the required high jet energy resolution at the future linear colliders, a large and finely segmented detector is needed. One option is to assemble a sandwich calorimeter out of many low-cost scintillators read out by silicon photomultipliers (SiPM). We characterize the areal homogeneity of SiPM response with the help of a highly collimated beam of pulsed visible light. The spatial resolution of the experiment reach the order of 1 μm and allows to study the active area structures within single SiPM microcells. Several SiPM models are characterized in terms of relative photon detection efficiency and probability

  3. InterTerm: los diccionarios de internet en un solo clic

    OpenAIRE

    M Gonzalo Claros

    2009-01-01

    En este artículo se presenta una herramienta que funciona en todos los ordenadores con tal de que se use un navegador que entienda el JavaScript estándar: InterTerm. Con ella se puede buscar una palabra en menos de un minuto en una buena colección de diccionarios y glosarios de la web. Se describe brevemente cómo utilizarlo, cómo se ven los resultados y por qué puede ser una herramienta interesante que merece ser añadida al disco duro y a los enlaces del navegador. La lista de sitios se puede...

  4. InterTerm: los diccionarios de internet en un solo clic

    Directory of Open Access Journals (Sweden)

    M. Gonzalo Claros

    2009-06-01

    Full Text Available En este artículo se presenta una herramienta que funciona en todos los ordenadores con tal de que se use un navegador que entienda el JavaScript estándar: InterTerm. Con ella se puede buscar una palabra en menos de un minuto en una buena colección de diccionarios y glosarios de la web. Se describe brevemente cómo utilizarlo, cómo se ven los resultados y por qué puede ser una herramienta interesante que merece ser añadida al disco duro y a los enlaces del navegador. La lista de sitios se puede modificar a voluntad del usuario, si se atreve a meterse en los entresijos del programa. Para empezar a probarlo, basta consultar la URL . ---------------------------------------------- InterTerm: Internet dictionaries at a single click. This article introduces InterTerm, a tool that runs in every type of computer using a browser with JavaScript standard. In less than a minute, this tool can search a word in a large collection of dictionaries and glossaries available in the web. This article briefly describes how to use it, how to see the results and the reasons why it's an interesting tool to install in the hard drive and to mark as a link in the browser. The user can modify the websites list if able to use the necessary skills to get into the program's ins and outs. To start testing this application, visit .

  5. Introducción: entre ladrillos y clics de ratón (bricks and clicks

    Directory of Open Access Journals (Sweden)

    Agustí, Lluís

    2002-03-01

    Full Text Available El Instituto Cervantes es la institución pública destinada a promover la enseñanza y el estudio de la lengua y la cultura española en el exterior, contribuyendo así al desarrollo y difusión de las culturas de España e Hispanoamericana. Para este fin dispone, además de los servicios centrales en Madrid, de una red de más de treinta centros en el mundo que cuentan en común básicamente proponer cursos de lengua, actividades relacionadas con la cultura y el espectáculo, y un servicio bibliotecario estable. Nacido al mismo tiempo que el Instituto Camões, su homólogo portugués, el Instituto Cervantes toma como referencias y modelo otras experiencias culturales occidentales previas: las Alianzas y los Institutos franceses, el Instituto Británico, el Goethe o el Dante Alighieri.

  6. Copper-to-silicon-carbide joints development for Future CLIC Hom Dampers

    CERN Document Server

    Gil Costa, Miguel

    2015-01-01

    Ceramic-to-metal joints have been of paramount importance for the nuclear and aeronautic industry since the last century. In this document, two different approaches to the Cu-to-SiC joining are briefly described and discussed. The first approach consists of an intermediate piece of lower Coefficient of Thermal Expansion than copper aiming to reduce the expansion mismatch with the ceramic during the brazing cycle. Soldering is selected as a second attempt, whose lower joining temperature reduces the absolute expansion difference between Cu and SiC. In addition, four SiC metallization processes are proposed and some of them have been also tested and discussed.

  7. Positron sources for electron-positron colliders application to the ILC and CLIC

    CERN Document Server

    CERN. Geneva

    2008-01-01

    The increased demanding qualities for positron sources dedicated to e+e- colliders pushed on investigations oriented on new kinds of e+ sources. The different kinds of positron sources polarized and no polarized are considered. Their main features (intensity, emittance) are described and analysed. Comparison between the different sources is worked out. The characteristics of the positron beam available in the collision point are greatly depending on the capture device and on the positron accelerator. Different kinds of capture systems are considered and their qualities, compared. Intense positron sources which are necessary for the colliders require intense incident beams (electrons or photons). The large number of pairs created in the targets leads to important energy deposition and so, thermal heating, which associated to temperature gradients provoke mechanical stresses often destructive. Moreover, the important Coulomb collisions, can affect the atomic structure in crystal targets and the radiation resist...

  8. Parametric study of the cost estimate for ultra precision RF components

    CERN Document Server

    Turunen, Joni; Osterberg, Kenneth; Makinen, Saku

    2011-01-01

    The purpose of this thesis was to find out how the shape accuracy and surface roughness of an RF disk affect the machining time of a disk and the cost of the accelerating structures. The disks in question are part of a future Compact Linear Collider (CLIC) project. This thesis was made because the price of a single disk is a major cost driver of the CLIC project. The cost of a disk is composed mainly of the time consuming ultra precise machining with expensive diamond tools. The surface roughness Ra 25 nm and shape accuracy 5 μm requirements are the reason for the need of ultra precision. The total number of disks to be produced for CLIC at 3 TeV center-of-mass energy is roughly 4.1 million, thus the project is a typical example of mass production where learning curves can be applied. Based on the theoretical calculations, changing the surface roughness Ra from 25 nm to 100 nm decreases the total ultra precise machining from 644 minutes to 311 minutes with current tooling and machining parameters. The effect...

  9. Parametric study of the cost estimate for radio frequency system of compact linear collider

    CERN Document Server

    Nummela, Antti; Österberg, Kenneth

    In this thesis the cost of so called RF units of CLIC particle collider was examined when RF units’ configuration was considered to be lengthened according to several alternative scenarios. According to current estimates these structures correspond to approximately 20 % of the total cost of CLIC collider and as such the savings achieved in their cost could be significant when total cost of CLIC project is looked into. The unit cost of longer RF units would be greater when compared to the baseline scenario but as smaller quantity would be required cost savings might be achieved. The aim was to find out if cost savings would accumulate and if so, how significant these savings might be. Research material used was mainly internal CERN resources such as earlier cost estimates and tenders received from the industry for production of different components. Based on these cost estimate models were created for three different configurations for lengthening the RF units. The research was limited to the cost of RF unit...

  10. Thermal fatigue issues in high-gradient particle accelerators

    CERN Document Server

    Heikkinen, Samuli Tapio; Neupert, Holger

    2006-01-01

    The CLIC (Compact LInear Collider) is being studied at CERN (European Organization for Nuclear Research) as a possible future high-energy (0.5-5 TeV centre-of-mass) physics facility. The current aim of the CLIC Study Team is to demonstrate the key feasibility issues before 2010. CLIC will be about 33 kilometers long and will be buried 100 meters underground. The main linac of CLIC consists of accelerating structures with the following demanding performance requirements: accelerating gradients of about 150 MV/m, power flows of about 200 MW, 1-2 ìm dimensional tolerances, an optical-quality surface finish and ultimately a low mass production cost. About 80% of CLIC's 33 kilometer length will be filled with main beam accelerating structures, which will require of the order of ten thousand tons of raw material and millions of individual parts. One of the main limiting factors of the main linac accelerating structures is the thermal fatigue due to the pulsed surface heating. The accelerating RFpower pulses heat u...

  11. Study and Development of a Laser Based Alignment System

    CERN Multimedia

    Stern, G

    2014-01-01

    CLIC (Compact Linear Collider) has tight requirements regarding pre-alignment of beam related components: 10 µm accuracy over a sliding window of 200 m along the 20 km of linac. To perform such an alignment, a new system is proposed combining laser beam as straight line reference and camera/shutter assemblies as sensors. The poster describes the alignment system and shows results regarding laser pointing stability with respect to time, shutter type, distance and environment. These results give a frame for future building and calibrating of sensors.

  12. Top quark pair production and calorimeter energy resolution studies at a future collider experiment

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Katja

    2012-03-27

    This thesis is focused on detector concepts and analyses investigated at a future linear electron positron collider. For precision measurements at such a collider, the CALICE collaboration develops imaging calorimeters, which are characterized by a fine granularity. CALICE has constructed prototypes of several design options for electromagnetic and hadronic calorimeters and has successfully operated these detectors during combined test beam programs at DESY, CERN and Fermilab. To improve the hadronic energy reconstruction and energy resolution of a hadron calorimeter prototype with analog readout three software compensation techniques are presented in this thesis, of which one is a local and two are global software compensation approaches. One method is based on a neural network to optimize the energy reconstruction, while two are energy weighting techniques, depending on the energy density. Weight factors are extracted from and applied to simulated and test beam data and result in an average energy resolution improvement of 15 - 25% compared to a reconstruction without software compensation. Whether such software compensation techniques are also applicable to a detector concept for a future linear electron positron collider is studied in the second part of this thesis. Simulated data, two different hadronic detector models and a local software compensation technique are used for this study. The energy resolutions for single hadrons and for jets are presented with and without software compensation. In the third part of this thesis, a study on top quark pair production at a center-of-mass energy of 500 GeV at the proposed electron positron collider CLIC is presented. The analysis is based on full detector simulations, including realistic background contributions dominated by two photon processes. The mass and width of the top quark are studied in fully-hadronic and semi-leptonic decays of top quark pairs using event samples of signal and Standard Model background

  13. CERN/KEK: Very high accelerating gradients

    International Nuclear Information System (INIS)

    Full text: A world-wide effort is under way to develop linear electron-positron colliders so that physics experiments can be extended into a range of energies where circular machines (necessarily much larger than CERN's 27-kilometre LEP machine) would be crippled by synchrotron radiation. CERN is studying the feasibility of building a 2 TeV machine called CLIC powered not by individual klystrons, but by a high intensity electron 'drive' linac running parallel to the main linac (November 1990, page 7). This drive linac will itself be powered by similar superconducting cavities to those developed for LEP. A high gradient is an obvious design aim for any future high energy linear collider because it makes it shorter and therefore cheaper - the design figure for the CLIC machine is 80 MV/m. The CLIC study group has taken a significant step forward in demonstrating the technical feasibility of their machine by achieving peak and average accelerating gradients of 137 MV/m and 84 MV/m respectively in a short section of accelerating structure during high gradient tests at the Japanese KEK Laboratory last year. This result obtained within the framework of a CERN/KEK collaboration on linear colliders was obtained using a 20-cell accelerating section built at CERN using state-of the- art technology which served both as a model for CLIC studies as well as a prototype for the Japanese Linear Collider studies. The operating frequency of the model accelerating section is 2.6 times lower than the CLIC frequency but was chosen because a high power r.f. source and pulse compression scheme has been developed for this frequency at KEK. Testing CLIC models at 11.4 GHz is however more stringent than at 30 GHz because the chance of electrical breakdown increases as the frequency is lowered. This recent result clearly demonstrates that a gradient of 80 MV/m is feasible

  14. Indirect search for color octet electron at next generation linear colliders

    CERN Document Server

    Akay, A N; Sahin, M; Sultansoy, S

    2010-01-01

    In this study we investigated indirect manifestations of color octet electron at the next generation linear colliders: International Linear Collider (ILC) and Compact Linear Collider (CLIC). Namely, production of two gluons via color octet electron exchange is considered. Signal and background analysis have been performed taking into account initial state radiation and beamstrahlung. We show that color octet electron (e_(8)) manifestation will be seen upto M(e_(8))=1.75 TeV and 1.70 TeV at ILC and CLIC with sqrt(s)=0.5 TeV, respectively. CLIC with sqrt(s)=3 TeV will be sensitive upto M(e_(8)=6.88 TeV.

  15. Recent Improvements to the Control of the CTF3 High-Current Drive Beam

    CERN Document Server

    Constance, B; Gamba, D; Skowronski, P K

    2013-01-01

    In order to demonstrate the feasibility of the CLIC multiTeV linear collider option, the drive beam complex at the CLIC Test Facility (CTF3) at CERN is providing highcurrent electron pulses for a number of related experiments. By means of a system of electron pulse compression and bunch frequency multiplication, a fully loaded, 120 MeV linac is used to generate 140 ns electron pulses of around 28 Amperes. Subsequent deceleration of this high-current drive beam demonstrates principles behind the CLIC acceleration scheme, and produces 12 GHz RF power for experimental purposes. As the facility has progressed toward routine operation, a number of studies aimed at improving the drive beam performance have been carried out. Additional feedbacks, automated steering programs, and improved control of optics and dispersion have contributed to a more stable, reproducible drive beam with consequent benefits for the experiments.

  16. Shower development of particles with momenta from 1 to 10 GeV in the CALICE Scintillator-Tungsten HCAL

    CERN Document Server

    Adloff, C; Chefdeville, M.; Drancourt, C.; Gaglione, R.; Geffroy, N.; Karyotakis, Y.; Koletsou, I.; Prast, J.; Vouters, G.; Repond, J.; Schlereth, J.; Smith, J; Xia, L.; Baldolemar, E.; Li, J.; Park, S.T.; Sosebee, M.; White, A.P.; Yu, J.; Eigen, G.; Thomson, M.A.; Ward, D.R.; Benchekroun, D.; Hoummada, A.; Khoulaki, Y.; Apostolakis, J.; Dannheim, D.; Dotti, A; Elsener, K.; Folger, G.; Grefe, C.; Ivantchenko, V.; Killenberg, M.; Klempt, W.; van der Kraaij, E.; Lam, C B; Linssen, L.; Lucaci-Timoce, A.-I.; Münnich, A.; Poss, S.; Ribon, A.; Sailer, A.; Schlatter, D.; Strube, J.; Uzhinskiy, V.; Carloganu, C.; Gay, P.; Manen, S.; Royer, L.; Tytgat, M; Zaganidis, N; Blazey, G C; Dyshkant, A; Lima, J G R; Zutshi, V; Hostachy, J-Y; Morin, L; Cornett, U.; David, D.; Ebrahimi, A.; Falley, G.; Feege, N.; Gadow, K.; Göttlicher, P.; Günter, C.; Hartbrich, O.; Hermberg, B.; Karstensen, S.; Krivan, F.; Krüger, K.; Lu, S.; Lutz, B.; Morozov, S.; Morgunov, V.; Neubüser, C.; Reinecke, M.; Sefkow, F.; Smirnov, P.; Terwort, M.; Garutti, E.; Laurien, S.; Marchesini, I.; Matysek, M.; Ramilli, M.; Briggl, K.; Eckert, P.; Harion, T.; Schultz-Coulon, H.-Ch.; Shen, W.; Stamen, R.; Bilki, B.; Norbeck, E.; Northacker, D.; Onel, Y.; Wilson, G.W.; Kawagoe, K.; Sudo, Y.; Yoshioka, T.; Dauncey, P.D.; Wing, M; Salvatore, F; Cortina Gil, E.; Mannai, S.; Baulieu, G.; Calabria, P.; Caponetto, L.; Combaret, C.; Della Negra, R.; Grenier, G.; Han, R.; Ianigro, J-C.; Kieffer, R.; Laktineh, I.; Lumb, N.; Mathez, H.; Mirabito, L.; Petrukhin, A.; Steen, A.; Tromeur, W.; Vander Donckt, M.; Zoccarato, Y.; Calvo Alamillo, E.; Fouz, M.-C.; Puerta-Pelayo, J.; Corriveau, F.; Bobchenko, B.; Chadeeva, M.; Danilov, M.; Epifantsev, A.; Markin, O.; Mizuk, R.; Novikov, E.; Popov, V; Rusinov, V.; Tarkovsky, E.; Kirikova, N.; Kozlov, V.; Smirnov, P; Soloviev, Y.; Besson, D.; Buzhan, P.; Ilyin, A.; Kantserov, V.; Kaplin, V.; Karakash, A; Popova, E.; Tikhomirov, V.; Kiesling, C.; Seidel, K.; Simon, F.; Soldner, C.; Szalay, M.; Tesar, M.; Weuste, L.; Amjad, M.S.; Bonis, J.; Callier, S; Conforti di Lorenzo, S.; Cornebise, P.; Doublet, Ph.; Dulucq, F.; Fleury, J.; Frisson, T.; van der Kolk, N.; Li, H.; Martin-Chassard, G.; Richard, F.; de la Taille, Ch.; Pöschl, R.; Raux, L.; Rouene, J.; Seguin-Moreau, N; Anduze, M.; Balagura, V.; Boudry, V.; Brient, J-C.; Cornat, R.; Frotin, M.; Gastaldi, F.; Guliyev, E.; Haddad, Y.; Magniette, F.; Musat, G.; Ruan, M.; Tran, T.H.; Videau, H.; Bulanek, B; Zacek, J.; Cvach, J.; Gallus, P.; Havranek, M.; Janata, M.; Kvasnicka, J.; Lednicky, D.; Marcisovsky, M.; Polak, I.; Popule, J.; Tomasek, L.; Tomasek, M.; Ruzicka, P.; Sicho, P.; Smolik, J.; Vrba, V.; Zalesak, J.; Belhorma, B.; Ghazlane, H.; Kotera, K.; Takeshita, T.; Uozumi, S.; Chang, S.; Khan, A.; Kim, D.H.; Kong, D.J.; Oh, Y.D.; Götze, M.; Sauer, J.; Weber, S.; Zeitnitz, C.

    2014-01-01

    Lepton colliders are considered as options to complement and to extend the physics programme at the Large Hadron Collider. The Compact Linear Collider (CLIC) is an $e^+e^-$ collider under development aiming at centre-of-mass energies of up to 3 TeV. For experiments at CLIC, a hadron sampling calorimeter with tungsten absorber is proposed. Such a calorimeter provides sufficient depth to contain high-energy showers, while allowing a compact size for the surrounding solenoid. A fine-grained calorimeter prototype with tungsten absorber plates and scintillator tiles read out by silicon photomultipliers was built and exposed to particle beams at CERN. Results obtained with electrons, pions and protons of momenta up to 10 GeV are presented in terms of energy resolution and shower shape studies. The results are compared with several GEANT4 simulation models in order to assess the reliability of the Monte Carlo predictions relevant for a future experiment at CLIC.

  17. Study of the Effect of Grafting Method on Surface Polarity of Tempo-Oxidized Nanocellulose Using Polycaprolactone as the Modifying Compound: Esterification versus Click-Chemistry

    OpenAIRE

    Abdelhaq Benkaddour; Khalil Jradi; Sylvain Robert; Claude Daneault

    2013-01-01

    Esterification and click-chemistry were evaluated as surface modification treatments for TEMPO-oxidized nanocelluloses (TONC) using Polycaprolactone-diol (PCL) as modifying compound in order to improve the dispersion of nanofibers in organic media. These two grafting strategies were analyzed and compared. The first consists of grafting directly the PCL onto TONC, and was carried out by esterification between hydroxyl groups of PCL and carboxyl groups of TONC. The second strategy known as clic...

  18. Single Z ' production at compact linear collider based on e-γ collisions

    International Nuclear Information System (INIS)

    We analyze the potential of the compact linear collider (CLIC) based on e-γ collisions to search for the new Z ' gauge boson. Single Z ' production on e-γ colliders in two SU(3)C x SU(3)L x U(1)N models, the minimal model and the model with right-handed neutrinos is studied in detail. The results show that new Z ' gauge bosons can be observed on the CLIC and that the cross sections in the model with right-handed neutrinos are bigger than those in the minimal one

  19. Single Z' production at compact linear collider based on e-γ collisions

    International Nuclear Information System (INIS)

    The potential of the compact linear collider (CLIC) based on e-γ collisions to search for the new Z' gauge boson. Single Z' production at e-γ colliders in two SU(3)C x SU(3)L x U(1)N models, the minimal model and the model with right-handed neutrinos is studied in detail. The results show that new Z' gauge bosons can be observed at the CLIC and that the cross sections in the model with right-handed neutrinos are bigger than those in the minimal one

  20. Alignment studies for the CERN linear collider

    International Nuclear Information System (INIS)

    Transverse alignment tolerances of a few microns are required for the CERN Linear Collider (CLIC) in order to limit the emittance blow-up due to transversely deflecting wakefields to reasonable values. Such tight tolerances over long distances can only be obtained by beam-based active alignment systems using precision micromovers and beam position monitors. Development work being carried out at CERN on closed-loop controlled micron-displacement systems, micron-resolution beam position monitors, active optical pre-alignment schemes and beam blow-up computer simulations for given overall alignment tolerances using both one-to-one and dispersion-free correction algorithms is described. (Author) 11 figs., 8 refs

  1. The collider of the future?

    CERN Multimedia

    2009-01-01

    Why are two studies for one linear collider being conducted in parallel? This is far from a duplication of effort or a waste of resources, since the two studies reflect a complementary strategy aimed at providing the best technology for future physics. On Friday 12 June CERN hosted the first joint meeting between CLIC, ILC and the CERN management.

  2. Investigation of the impact of extreme air temperature on river water temperature: case study of the heat episode 2013.

    Science.gov (United States)

    Weihs, Philipp; Trimmel, Heidelinde; Goler, Robert; Formayer, Herbert; Holzapfel, Gerda; Rauch, Hans Peter

    2014-05-01

    Water stream temperature is a relevant factor for water quality since it is an important driver of water oxygen content and in turn also reduces or increases stress on the aquatic fauna. The water temperature of streams is determined by the source and inflow water temperature, by the energy balance at the stream surface and by the hydrological regime of the stream. Main factors driving the energy balance of streams are radiation balance and air temperature which influences the sensitive and latent heat flux. The present study investigates the impact of the heat episode of summer 2013 on water temperature of two lowland rivers in south eastern Austria. Within the scope of the project BIO_CLIC routine measurements of water temperature at 33 locations alongside the rivers Pinka and Lafnitz have been performed since spring 2012. In addition meteorological measurements of global shortwave and longwave radiation, air temperature, wind and air humidity have been carried out during this time. For the same time period, data of discharge and water levels of both rivers were provided by the public hydrological office. The heat episode of summer 2013 started, according to the Kysely- definition, on 18 July and lasted until 14 August. The highest air temperature ever recorded in Austria was reported on 8 August at 40.5°C. In Güssing, which is located within the project area, 40.0 °C were recorded. In the lower reaches of the river Pinka, at the station Burg the monthly mean water temperature of August 2013 was with more than 22°C, 1°C higher than the mean water temperature of the same period of the previous years. At the same station, the maximum water temperature of 27.1°C was recorded on 29 July, 9 days prior to the air temperature record. Analysis shows that at the downstream stations the main driving parameter is solar radiation whereas at the upstream stations a better correlation between air temperature and water temperature is obtained. Using the extensive data set

  3. Heribert KOZIOL's retirement party

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    Photo 09: L. to r. : Simon van der Meer (inventor of 'Stochastic Cooling', Nobel prize 1984), Kurt Hubner, Director of Accelerators) Photo 11: L. to r.: Renzo Resegotti (builder of the ISR magnets), Simon van der Meer , Kurt Hubner Photo 17: Heribert Koziol (longtime PS-Divisions Beam Diagnostics Group Leader) Radio-Frequency Groups; former CLIC Study Leader),

  4. Parental Tobacco Smoking and Acute Myeloid Leukemia: The Childhood Leukemia International Consortium.

    Science.gov (United States)

    Metayer, Catherine; Petridou, Eleni; Aranguré, Juan Manuel Mejía; Roman, Eve; Schüz, Joachim; Magnani, Corrado; Mora, Ana Maria; Mueller, Beth A; de Oliveira, Maria S Pombo; Dockerty, John D; McCauley, Kathryn; Lightfoot, Tracy; Hatzipantelis, Emmanouel; Rudant, Jérémie; Flores-Lujano, Janet; Kaatsch, Peter; Miligi, Lucia; Wesseling, Catharina; Doody, David R; Moschovi, Maria; Orsi, Laurent; Mattioli, Stefano; Selvin, Steve; Kang, Alice Y; Clavel, Jacqueline

    2016-08-15

    The association between tobacco smoke and acute myeloid leukemia (AML) is well established in adults but not in children. Individual-level data on parental cigarette smoking were obtained from 12 case-control studies from the Childhood Leukemia International Consortium (CLIC, 1974-2012), including 1,330 AML cases diagnosed at age controls. We conducted pooled analyses of CLIC studies, as well as meta-analyses of CLIC and non-CLIC studies. Overall, maternal smoking before, during, or after pregnancy was not associated with childhood AML; there was a suggestion, however, that smoking during pregnancy was associated with an increased risk in Hispanics (odds ratio = 2.08, 95% confidence interval (CI): 1.20, 3.61) but not in other ethnic groups. By contrast, the odds ratios for paternal lifetime smoking were 1.34 (95% CI: 1.11, 1.62) and 1.18 (95% CI: 0.92, 1.51) in pooled and meta-analyses, respectively. Overall, increased risks from 1.2- to 1.3-fold were observed for pre- and postnatal smoking (P < 0.05), with higher risks reported for heavy smokers. Associations with paternal smoking varied by histological type. Our analyses suggest an association between paternal smoking and childhood AML. The association with maternal smoking appears limited to Hispanic children, raising questions about ethnic differences in tobacco-related exposures and biological mechanisms, as well as study-specific biases. PMID:27492895

  5. Authors or signatories?

    CERN Multimedia

    James Gillies

    2012-01-01

    Over recent years, the traditional author list has been joined by a new kid on the block: a signatory list, used by projects ranging from TESLA to SuperB, and soon to be joined by CLIC. What’s the difference?   Next week, the Conceptual Design Report (CDR) for CLIC Physics and Detectors will be published, and it will be fronted by a signatory list of over 1000 people. A volume describing the CLIC accelerator will follow soon after. CLIC, the Compact Linear Collider, is an international study for a possible future particle physics research facility, and one of several options on the table for the post-LHC era. Keeping future options open has been part of the normal run of things since particle-physics-time-immemorial: several technologies are studied and developed in parallel so that when the physics results from operating facilities point the way forward, the community can choose the best option for the physics, and for the available resources. “Long-term R&D is essen...

  6. Development of Stripline Kickers for Low Emittance Rings: Application to the Beam Extraction Kicker for CLIC Damping Rings

    OpenAIRE

    Belver Aguilar, Carolina

    2015-01-01

    El descubrimiento del bosón de Higgs ha iniciado una nueva era en el LHC cuyo objetivo será medir las propiedades de dicho bosón con la mayor precisión posible. Sin embargo, dada la complejidad de los protones, compuestos por quarks y gluones, existe el consenso en la Física de Altas Energías de que el próximo colisionador será un colisionador electrón-positrón. Desde un punto de vista simplista, para que electrones y positrones colisionen a muy altas energías en un colisionador circular, la ...

  7. Transient beam-loading model and compensation in Compact Linear Collider main linac

    CERN Document Server

    Kononenko, O

    2011-01-01

    A new model to compensate for the transient beam loading in the CLIC main linac is developed. It takes into account the CLIC specific power generation scheme and the exact 3D geometry of the accelerating structure including couplers. A new method of calculating unloaded and loaded voltages during the transient is proposed and a dedicated optimization scheme of the rf pulse to compensate the transient beam-loading effect is presented. It is demonstrated that the 0.03% limit on the rms relative bunch-to-bunch energy spread in the main beam after acceleration can be reached. The optimization technique has been used to increase the rf to beam efficiency while preserving the CLIC requirements and to compensate for the energy spread caused by the Balakin-Novokhatski-Smirnov damping and transient process in the subharmonic buncher. Effects of charge jitters in the drive and main beams are studied. It is shown that within the 0.1% CLIC specification limit on the rms spread in beams charge the energy spread is not sig...

  8. Study of charged and neutral minimal supersymmetric standard model Higgs boson decays and measurement of tan at the compact linear collider

    Indian Academy of Sciences (India)

    E Coniavitis; A Ferrari

    2007-12-01

    The minimal supersymmetric extension of the standard model (MSSM) predicts the existence of new charged and neutral Higgs bosons. The pair creation of these new particles at the multi-TeV + - compact linear collider (CLIC), followed by decays into standard model particles, were simulated along with the corresponding background. High-energy beam-beam effects such as ISR, beamstrahlung and hadronic background were included. We have investigated the possibility of using the ratio between the number of events found in various decay channels to determine the MSSM parameter tan and we have derived the corresponding statistical error from the uncertainties on the measured cross-sections and Higgs boson masses.

  9. The collider of the future?

    CERN Multimedia

    CERN Audiovisual Service

    2009-01-01

    Why are two studies for one linear collider being conducted in parallel? This is far from a duplication of effort or a waste of resources, since the two studies reflect a complementary strategy aimed at providing the best technology for future physics. On Friday 12 June CERN hosted the first joint meeting between CLIC and ILC, which led to a host of good results and important decisions. The International Linear Collider (ILC) and Compact Linear Collider (CLIC) studies both call for cutting-edge technologies. At first glance they may appear to be in competition, but they are in fact complementary and have a common objective – namely to propose a design , as soon as possible and at the lowest possible cost, for the linear accelerator best suited to taking over the baton of physics research at the high-energy frontier after the LHC.

  10. Beam dynamics studies and emittance optimization in the CTF3 linac at CERN

    CERN Document Server

    Urschütz, Peter; Corsini, Roberto; Döbert, Steffen; Ferrari, Arnaud; Tecker, Frank

    2006-01-01

    Small transverse beam emittances and well-known lattice functions are crucial for the 30 GHz power production in the Power Extraction and Transfer Structure (PETS) and for the commissioning of the Delay Loop of the CLIC Test Facility 3 (CTF3). Following beam dynamics simulation results, two additional solenoids were installed in the CTF3 injector in order to improve the emittance. During the runs in 2005 and 2006, an intensive measurement campaign to determine Twiss parameters and beam sizes was launched. The results obtained by means of quadrupole scans for different modes of operation suggest emittances well below the nominal .n,rms = 100 ?Î?Êm and a good agreement with PARMELA simulations.

  11. Textbook tests with tungsten

    CERN Multimedia

    Barbara Warmbein

    2010-01-01

    CERN's linear collider detector group joins forces with CALICE in building the world's first tungsten hadronic calorimeter.   Hadronic calorimeter prototype made of tungsten for the linear collider detector being equipped with CALICE scintillators. In a hall for test beam experiments at CERN, next to the CLOUD climate experiment and an irradiation facility, sits a detector prototype that is in many ways a first. It's the first ever hadronic sandwich calorimeter (HCal) prototype made of tungsten. It's the first prototype for a detector for the Compact Linear Collider Study CLIC, developed by the linear collider detector R&D group (LCD group) at CERN. And it's the first piece of hardware that results directly from the cooperation between CLIC and ILC detector study groups. Now its makers are keen to see first particle showers in their detector. The tungsten calorimeter has just moved from a workshop at CERN, where it was assembled from finely polished tungsten squares and triangles, into the ...

  12. Feasibility of Geiger-mode avalanche photodiodes in CMOS standard technologies for tracker detectors

    OpenAIRE

    Vilella Figueras, Eva

    2013-01-01

    The next generation of particle colliders will be characterized by linear lepton colliders, where the collisions between electrons and positrons will allow to study in great detail the new particle discovered at CERN in 2012 (presumably the Higgs boson). At present time, there are two alternative projects underway, namely the ILC (International Linear Collider) and CLIC (Compact LInear Collider). From the detector point of view, the physics aims at these particle colliders impose such extreme...

  13. Metrological Characterization of an Ultra-low Noise Acquisition System for Fast Voltage Pulses Measurements

    CERN Document Server

    Baccigalupi, Carlo; Martino, Michele

    2015-01-01

    The metrological characterization of a custom designed ultra-low noise analogue front-end for an acquisition system for the measurement of flat-top of fast voltage pulses is presented. The system has challenging r quirements, in particular for Common Mode Rejection Ratio (C M RR), thus custom methods have been defined, by illustrating the experimental results achieved at the European Organization for Nuclear Research (CERN) during the study of the new Compact LInear Collider (CLIC).

  14. A Search for leptophlic Z_(l) boson at future linear colliders

    CERN Document Server

    Kara, S O; Sultansoy, S; Turkoz, S

    2011-01-01

    We study the possible dynamics associated with leptonic charge in future linear colliders. Leptophilic massive vector boson, Z_(l), have been investigated through the process e^(+)e^(-) -> mu^(+)mu^(-). We have shown that ILC and CLIC will give opportunity to observe Z_(l) with masses up to the center of mass energy if the corresponding coupling constant g_(l) exceeds 10^(-3).

  15. POSIPOL participants in front of the Globe of Innovation.

    CERN Document Server

    Maximilien Brice

    2006-01-01

    POSIPOL 2006, an international workshop that was held earlier this year at CERN, was dedicated to the production of polarized positrons using the Compton back-scattering of a high-power laser beam by electrons of a few giga-electron-volts. The particular focus was on applications to the two future linear-collider studies, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC).

  16. Choke-mode damped structure design for the Compact Linear Collider main linac

    CERN Document Server

    Zha, Hao; Grudiev, Alexej; Huang, Wenhui; Shi, Jiaru; Tang, Chuanxiang; Wuensch, Walter

    2012-01-01

    Choke-mode damped structures are being studied as an alternative design to waveguide damped structures for the main linac of the Compact Linear Collider (CLIC). Choke-mode structures have the potential for lower pulsed temperature rise and simpler and less expensive fabrication. An equivalent circuit model based on transmission line theory for higher-order-mode damping is presented. Using this model, a new choke geometry is proposed and the wakefield performance is verified using GDFIDL. This structure has a comparable wakefield damping effect to the baseline design which uses waveguide damping. A prototype structure with the same iris dimensions and accelerating gradient as the nominal CLIC design, but with the new choke geometry, has been designed for high-power tests. DOI: 10.1103/PhysRevSTAB.15.122003

  17. Design of a dependable Interlock System for linear colliders

    CERN Document Server

    Nouvel, Patrice

    For high energy accelerators, the interlock system is a key part of the machine protection. The interlock principle is to inhibit the beam either on failure of critical equipment and/or on low beam quality evaluation. The dependability of such a system is the most critical parameter. This thesis presents the design of an dependable interlock system for linear collider with an application to the CLIC (Compact Linear Collider) project. This design process is based on the IEEE 1220 standard and is is divided in four steps. First, the specifications are established, with a focus on the dependability, more precisely the reliability and the availability of the system. The second step is the design proposal based on a functional analysis, the CLIC and interfaced systems architecture. Third, the feasibility study is performed, applying the concepts in an accelerator facility. Finally, the last step is the hardware verification. Its aim is to prove that the proposed design is able to reach the requirements.

  18. Impact of detector solenoid on the Compact Linear Collider luminosity performance

    CERN Document Server

    Levinsen, Yngve Inntjore; Tomas, Rogelio; Schulte, Daniel

    2014-01-01

    In order to obtain the necessary luminosity with a reasonable amount of beam power, the Compact Linear Collider (CLIC) design includes an unprecedented collision beam size of {\\sigma} = 1 nm vertically and {\\sigma} = 45 nm horizontally. Given the small and very flat beams, the luminosity can be significantly degraded from the impact of the experimental solenoid field in combination with a large crossing angle. Main effects include y-x'-coupling and increase of vertical dispersion. Additionally, Incoherent Synchrotron Radiation (ISR) from the orbit deflection created by the solenoid field, increases the beam emittance. A detailed study of the impact from a realistic solenoid field and the associated correction techniques for the CLIC Final Focus is presented. In particular, the impact of techniques to compensate the beam optics distortions due to the detector solenoid main field and its overlap with the final focus magnets are shown. The unrecoverable luminosity loss due to ISR has been evaluated, and found to...

  19. Design of a Solid-State Fast Voltage Compensator for klystron modulators requiring constant AC power consumption

    CERN Document Server

    Aguglia, Davide; Viarouge, Philippe; Cros, Jerome

    2014-01-01

    This paper proposes a novel topological solution for klystron modulators integrating a Fast Voltage Compensator which allows an operation at constant power consumption from the utility grid. This kind of solution is mandatory for the CLIC project under study, which requires several hundreds of synchronously operated klystron modulators for a total pulsed power of 39 GW. The topology is optimized for the challenging CLIC specifications, which require a very precise output voltage flat-top as well as fast rise and fall times (3µs). The Fast Voltage Compensator is integrated in the modulator such that it only has to manage the capacitor charger current and a fraction of the charging voltage. Consequently, its dimensioning power and cost is minimized.

  20. Investigation of the energy dependence of breakdown properties with a DC spark setup

    CERN Document Server

    Hansen, Anita; Calatroni, S

    2009-01-01

    The Compact LInear Collider (CLIC) study is a site independent feasibility study aiming at the development of a realistic technology at an affordable cost for a future linear electron-positron collider. The European Organization for Nuclear Research (CERN) is one of the collaborators for the CLIC study.The CLIC Test Facility (CTF3) positioned at CERN provides testing of this technology, including the testing of the proposed radio-frequency (RF) structures in a two-beam concept to produce the necessary accelerating electric field as high as 100 MV/m to reach the goal of a nominal total energy of 3 TeV. One problem at such high accelerating fields is electrical discharges, i.e. sparks, damaging the inside of the RF structures as well as deflecting the trajectories of accelerated particles. A Direct Current (DC) spark test setup is in use at CERN to aid the understanding of electrical discharges under vacuum conditions, also called vacuum arcs. In contrast to the more complex CTF3 setup, the DC spark setup is si...

  1. Influence of grain orientation on evolution of surface features in fatigued polycrystalline copper: A comparison of thermal and uniaxial mechanical fatigue results

    International Nuclear Information System (INIS)

    Surface state plays a major role in the crack nucleation process of pure metals in the High-Cycle-Fatigue (HCF) as well as in the Ultra-High-Cycle-Fatigue (UHCF) regime. Therefore, in studies dealing with HCF or UHCF, special attention is paid to the evolution of surface degradation during fatigue life. The accelerating structures of the future Compact Linear Collider (CLIC) under study at CERN will be submitted to a high number of thermal-mechanical fatigue cycles, arising from Radio Frequency (RF) induced eddy currents, causing local superficial cyclic heating. The number of cycles during the foreseen lifetime of CLIC reaches 2x1011. Fatigue may limit the lifetime of CLIC structures. In order to assess the effects of superficial fatigue, specific tests are defined and performed on polycrystalline Oxygen Free Electronic (OFE) grade Copper, a candidate material for the structures. Surface degradation depends on the orientation of near-surface grains. Copper samples thermally fatigued in two different fatigue experiments, pulsed laser and pulsed RF-heating, underwent postmortem Electron Backscattered Diffraction measurements. Samples fatigued by pulsed laser show the same trend in the orientation-fatigue damage behavior as samples fatigued by pulsed RF-heating. It is clearly observed that surface grains, oriented [1 1 1] with respect to the surface, show significantly more damage than surface grains oriented [1 0 0]. Results arising from a third fatigue experiment, the ultrasound (US) swinger, are compared to the results of the mentioned experiments. The US swinger is an uniaxial mechanical fatigue test enabling to apply within several days a total number of cycles representative of the life of the CLIC structures, thanks to a high repetition rate of 24 kHz. For comparison, laser fatigue experiments have much lower repetition rates. The dependence of surface degradation on grain orientation of samples tested by the US swinger was monitored during the fatigue life

  2. Emittance optimisation in the Drive Beam Recombination Complex at CTF3

    CERN Document Server

    Gamba, D

    2014-01-01

    According to the Conceptual Design Report, the power to accelerate the main colliding beams of CLIC is taken from parallel high intensity (100 A), low energy (2.37 GeV) beams. These beams are generated by long trains, accelerated by conventional klystrons and then time-compressed in the so called Drive-Beam Recombination Complex (DBRC). A scaled version of the DBRC has been built at the CLIC Test Facility (CTF3) at CERN in order to prove its principle and study any arising feasibility issues. One of the main constraints is the emittance control during the recombination process. This work presents an overview of the studies ongoing at CTF3, keeping in view possible improvements of the nominal CLIC design. In particular, a generic feedback algorithm to solve (quasi-)linear systems has been implemented and used in order to optimize the process by tuning the energy of the beam and steer the orbits in the different lines, as well matching the design dispersion. Current results and possible room for further optimiz...

  3. Influence of grain orientation on evolution of surface features in fatigued polycrystalline copper: a comparison of thermal and uniaxial mechanical fatigue results

    CERN Document Server

    Aicheler, M

    2010-01-01

    Surface state plays a major role in the crack nucleation process of pure metals in the High-Cycle-Fatigue (HCF) as well as in the Ultra-High-Cycle-Fatigue (UHCF) regime. Therefore, in studies dealing with HCF or UHCF, special attention is paid to the evolution of surface degradation during fatigue life. The accelerating structures of the future Compact Linear Collider (CLIC) under study at CERN will be submitted to a high number of thermal-mechanical fatigue cycles, arising from Radio Frequency (RF) induced eddy currents, causing local superficial cyclic heating. The number of cycles during the foreseen lifetime of CLIC reaches 2x10(11). Fatigue may limit the lifetime of CLIC structures. In order to assess the effects of superficial fatigue, specific tests are defined and performed on polycrystalline Oxygen Free Electronic (OFE) grade Copper, a candidate material for the structures. Surface degradation depends on the orientation of near-surface grains. Copper samples thermally fatigued in two different fatigu...

  4. Definition of a reference metrology network for the positioning of a large linear accelerator

    International Nuclear Information System (INIS)

    This thesis is a study of the Compact Linear Collider (CLIC) alignment system, a project of linear accelerator of about 30 km long of the European Organization for Nuclear Research (CERN). The pre-alignment tolerance on the transverse positions of the components of the CLIC linacs is typically ten microns over distances of 200 m. This research is a consequence of 10 years work, where several sets of special sensors dedicated to metrology have been adapted for the CLIC project. Most of these sensors deliver measurements linked to geometric references sensitive to gravity fluctuation. An important part of this work is therefore dedicated to study the gravity disruptions as a high level of accuracy is required. The parameters to take into account in the use of the hydrostatic leveling have thus been highlighted. A proposal of configuration of the system alignment based on a selection of sensors has also been given in this research. Computer models of different possible configurations have been presented. As the existing computing software was inappropriate, a new object oriented software package has been developed, to ensure future upgrades. An optimized configuration of the network has been defined from a set of simulations. Finally, due to problems in the use of hydrostatic leveling systems, a solution based on the use of a long laser beam as an alternative solution is discussed. (author)

  5. Definition of a reference metrology network for the positioning of a large linear accelerator; Definition d'un reseau de reference metrologique pour le positionnement d'un grand accelerateur lineaire

    Energy Technology Data Exchange (ETDEWEB)

    Becker, F

    2003-12-15

    This thesis is a study of the Compact Linear Collider (CLIC) alignment system, a project of linear accelerator of about 30 km long of the European Organization for Nuclear Research (CERN). The pre-alignment tolerance on the transverse positions of the components of the CLIC linacs is typically ten microns over distances of 200 m. This research is a consequence of 10 years work, where several sets of special sensors dedicated to metrology have been adapted for the CLIC project. Most of these sensors deliver measurements linked to geometric references sensitive to gravity fluctuation. An important part of this work is therefore dedicated to study the gravity disruptions as a high level of accuracy is required. The parameters to take into account in the use of the hydrostatic leveling have thus been highlighted. A proposal of configuration of the system alignment based on a selection of sensors has also been given in this research. Computer models of different possible configurations have been presented. As the existing computing software was inappropriate, a new object oriented software package has been developed, to ensure future upgrades. An optimized configuration of the network has been defined from a set of simulations. Finally, due to problems in the use of hydrostatic leveling systems, a solution based on the use of a long laser beam as an alternative solution is discussed. (author)

  6. Beam Momentum Changes due to Discharges in High-gradient Accelerator Structures

    CERN Document Server

    Palaia, Andrea; Ruber, Roger; Ekelöf, Tord

    2013-11-21

    The key questions left unanswered by the Standard Model, and the recent discovery of a Standard Model-like Higgs boson, demand an extension of the research on particle physics to the TeV energy scale. The Compact Linear Collider, CLIC, is a candidate project to achieve such goal. It is a linear lepton collider based on a novel two-beam acceleration scheme capable of high-gradient acceleration in X-band accelerator structures. The high electric fields required, however, entail the occurrence of vacuum discharges, or rf breakdowns, a phenomenon whose microscopic dynamics is not yet completely understood, and whose impact on the beam can lead to a severe degradation of the collider luminosity. The understanding of the physics of rf breakdowns has therefore become a significant issue in the design of a reliable accelerator based on CLIC technology. That is addressed experimentally through the study of accelerator structures performance during high-power operations. We report on such a study carried out on a CLIC...

  7. Thermally Induced Ultra High Cycle Fatigue of Copper Alloys of the High Gradient Accelerating Structures

    CERN Document Server

    Heikkinen, Samuli; Wuensch, Walter

    2010-01-01

    In order to keep the overall length of the compact linear collider (CLIC), currently being studied at the European Organization for Nuclear Research (CERN), within reasonable limits, i.e. less than 50 km, an accelerating gradient above 100 MV/m is required. This imposes considerable demands on the materials of the accelerating structures. The internal surfaces of these core components of a linear accelerator are exposed to pulsed radio frequency (RF) currents resulting in cyclic thermal stresses expected to cause surface damage by fatigue. The designed lifetime of CLIC is 20 years, which results in a number of thermal stress cycles of the order of 2.33•1010. Since no fatigue data existed in the literature for CLIC parameter space, a set of three complementary experiments were initiated: ultra high cycle mechanical fatigue by ultrasound, low cycle fatigue by pulsed laser irradiation and low cycle thermal fatigue by high power microwaves, each test representing a subset of the original problem. High conductiv...

  8. oWPS VERSUS cWPS

    CERN Document Server

    Mainaud Durand, H; Herty, A; Marin, A; Rude, V

    2012-01-01

    The strategy of the CLIC pre-alignment relies on Wire Positioning Sensors (WPS) measuring the radial and vertical offsets with respect to a stretched wire. A precision below 2 µm and an accuracy of 5 µm over a whole range of measurement of 10 mm per axis are required for these sensors. Two types of sensors, based on two different technologies are under development and study at CERN: the capacitive sensor (cWPS) is already in use for the monitoring of the position of the low beta triplets in the LHC and the optical sensor (oWPS) is currently under development with Open Source Instruments. The cWPS had to be upgraded in order to reach the specifications required by the CLIC alignment. The oWPS is a new development especially designed to the CLIC demands. The paper presents the two types of sensors, the developments, as well as the latest results obtained in validation tests. These two types of sensors are part of a common test setup: results of inter-comparison tests achieved on this setup are detailed.

  9. Manufacturing and Testing of a TBL PETS Prototype

    CERN Document Server

    Toral, Fernando; Calero, Jesus; Carrillo, David; De Aragon, Fernando; Garcia-Tabares, Luis; Gutierrez, Jose Luis; Lara, Alvaro; Rodriguez Garcia, Enrique; Sanchez, Laura; Dobert, Steffen; Syratchev, Igor

    2010-01-01

    The goal of the present CLIC Test Facility (CTF3) is to demonstrate the technical feasibility of the CLIC scheme. The Test Beam Line (TBL) is used to study a CLIC decelerator focusing on 12 GHz power production and the stability of the decelerated beam. The extracted CTF3 drive beam from the Combiner Ring (CR) features a maximum intensity of 28 A and 140 ns pulse duration, where the Test Beam Line consists of 16 cells, each one including a BPM, a quadrupole on top of a micrometeraccuracy mover and a RF power extractor so-called PETS (Power Extraction and Transfer Structure). This paper describes the first prototype fabrication techniques, with particular attention to the production of the long copper rods which induce the RF generation. A special test bench for the characterization of the device with low RF power measurements has been developed. Performed measurements of the scattering parameters and the electric field profile along the structure are carefully described. Finally, the prototype has been instal...

  10. The CLIC Test Facility (CTF3) which allowed the first electron beam recombination in order to multiply the RF frequency from 3 GHz up to 15 GHz.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Photo 0210005_11: The CTF3 linac accelerates an electron beam up to 350 MeV. Photo 0210005_1: At the front, the yellow dipole is used for the spectrometer line. At the back, a doublet of blue quadrupole for the matching. Photo 0210005_03: The CTF3 transfer line between the electron linac and the isochronous ring. Photo 0210005_04: One arc of the EPA isochronous ring. Photo 0210005_06: The CTF3 bunching system. The first RF wave guide feeds the Pre-Buncher while the second RF wave guide feeds the Buncher. They provide a bunched electron beam at 4 MeV. The blue magnet is a solenoid around the Buncher. Photo 0210005_07: A LIL accelerating structure used for CTF3. It is 4.5 meters long and provides an energy gain of 45 MeV. One can see 3 quadrupoles around the RF structure.

  11. Pulmonary studies

    International Nuclear Information System (INIS)

    Radionuclide studies of the lung are described, as regards perfusion studies, ventilation studies and physiological considerations. The four principal applications for radionuclide studies of the lungs are outlined and the uses of these discussed in relation to particular entities including pulmonary embolic disease, congestive heart failure, asthma, acute, nonasthmatic, bronchial obstruction, chronic pulmonary disease and cancer. (Auth./C.F.)

  12. Cystometric study

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003904.htm Cystometric study To use the sharing features on this page, please enable JavaScript. Cystometric study measures the amount of fluid in the bladder ...

  13. Initial Study

    DEFF Research Database (Denmark)

    Torp, Kristian

    2009-01-01

    increased. In the initial study presented here, the time it takes to pass an intersection is studied in details. Two major signal-controlled four-way intersections in the center of the city Aalborg are studied in details to estimate the congestion levels in these intersections, based on the time it takes to...

  14. Case Studies

    International Nuclear Information System (INIS)

    Proven options available to Sri Lanka for large scale electricity generation in the future are coal-fired thermal, oil-fired thermal and Nuclear. Four case studies for groups participated are indicated. Case study for group 1 is comparison of the three options by taking into consideration the capital and recurrent expenditure involved. Environmental effects of the three options are also given. Case study for group 2 is economic comparison of three renewable energy based power generation system. Case study for group 3 is based on energy conservation, efficiency, improvement and demand management. Assuming that a continuous saving of 20 MW of demand from 1996 onwards is effective two projects are suggested to achieve this result. Case study for group 4 is a feasibility study for hydro power development of the Kukule Ganga (river) in Sri Lanka. Participants are required to evaluate one of the three optional development concepts which are technically feasible

  15. Security studies

    International Nuclear Information System (INIS)

    The so called 'Security Studies' constitute one of the major tools for evaluating the provisions implemented at facilities to protect and control nuclear material (NM) against unauthorized removal. Operators use security studies to demonstrate that they are complying with objectives set by the Competent Authority to counter internal or external acts aimed at unauthorized removal of nuclear material. The paper presents the context of security studies carried out in France. (author)

  16. Absorption studies

    International Nuclear Information System (INIS)

    Absorption studies were once quite popular but hardly anyone does them these days. It is easier to estimate the blood level of the nutrient directly by radioimmunoassay (RIA). However, the information obtained by estimating the blood levels of the nutrients is not the same that can be obtained from the absorption studies. Absorption studies are primarily done to find out whether some of the essential nutrients are absorbed from the gut or not and if they are absorbed, to determine how much is being absorbed. In the advanced countries, these tests were mostly done to detect pernicious anaemia where vitamin B12 is not absorbed because of the lack of the intrinsic factor in the stomach. In the tropical countries, ''malabsorption syndrome'' is quire common. In this condition, several nutrients like fat, folic acid and vitamin B12 are not absorbed. It is possible to study absorption of these nutrients by radioisotopic absorption studies

  17. Studying Sideways

    DEFF Research Database (Denmark)

    Plesner, Ursula

    2011-01-01

    inequalities in relation to the people we study. This article argues that not all types of social scientific research interviews benefit from an à priori problematization of power and control, ethics and equality, or emancipation. From a constructivist perspective, the article seeks to displace the...... methodological concern with power related to the ideas of studying up or down and introduce another set of concerns in relation to producing good empirical material when we “study sideways.” The argument is based on analyses of interview situations from a concrete research project, where researcher and...... researched share professional background to some degree, where negotiations replace a researcher-imposed dialogue, and where the circulation of shared or common concepts messes up an orderly division between researchers’ vocabulary and interviewees’ vocabularies. It is proposed that when we study sideways...

  18. Floodplain Study

    Data.gov (United States)

    Montgomery County of Maryland — The purpose of a floodplain study is to establish the 100-year floodplain limits within or near a development in order to preserve the natural resources within the...

  19. Actuarial Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Office of the Actuary in the Centers for Medicare and Medicaid Services (CMS) from time to time conducts studies on various aspects of the Medicare and Medicaid...

  20. Feasibility study

    International Nuclear Information System (INIS)

    The feasibility study itself examines the technical, economic and financial implications of a nuclear power station in depth so as to make sure that nuclear power is the right course to take. This means that it is quite an expensive operation and it is to avoid wasting this money that a pre-feasibility study is carried out. This preliminary study should eliminate cases where the electrical system cannot absorb the capacity of a nuclear station of commercial size, where other sources of power such as hydro-electricity, gas or cheap coal would make nuclear obviously uneconomic or where no suitable sites exist. If this first rather simple survey shows that nuclear power is a credible solution to a utilities need for electricity or heat production plant, then the next stage is a full feasibility study. (orig./TK)

  1. Invisibility Studies

    DEFF Research Database (Denmark)

    Invisibility Studies explores current changes in the relationship between what we consider visible and what invisible in different areas of contemporary culture. Contributions trace how these changes make their marks on various cultural fields and investigate the cultural significance of these...... conditioned by physical and social settings that create certain possibilities for visibility and visuality, yet exclude others. The richness and complexity of this cultural framework means that no single discipline or interdisciplinary approach could capture it single-handedly. Invisibility Studies begins...

  2. Photon-Photon and Electron-Photon Colliders with Energies Below a TeV

    CERN Document Server

    Velasco, Mayda M; Barenboim, Gabriela; Logan, Heather E.; Atwood, David; Godfrey, Stephen; Kalyniak, Pat; Doncheski, Michael A; Burkhardt, Helmut; de Roeck, Albert; Ellis, John; Schulte, Daniel; Zimmermnn, Frank; Gunion, John F; Asner, David M; Gronberg, Jeff B; Hill, Tony S; Van Bibber, Karl; Hewett, JoAnne L; Petriello, Frank J; Rizzo, Thomas; Velasco, Mayda M.

    2001-01-01

    We investigate the potential for detecting and studying Higgs bosons in $\\gamma\\gamma$ and $e\\gamma$ collisions at future linear colliders with energies below a TeV. Our study incorporates realistic $\\gamma\\gamma$ spectra based on available laser technology, and NLC and CLIC acceleration techniques. Results include detector simulations. We study the cases of: a) a SM-like Higgs boson based on a devoted low energy machine with $\\sqrt{s_{ee}}\\le 200$ GeV; b) the heavy MSSM Higgs bosons; and c) charged Higgs bosons in $e\\gamma$ collisions.

  3. Treatability studies

    DEFF Research Database (Denmark)

    Bennedsen, Lars Rønn; Studds, Phil

    The fundamental information that a well-designed treatability study can provide is essential to the success of all remediation systems. Over the past years several new techniques for in situ and on site remediation of contaminated soil and groundwater have been used with varying degrees of success...... ends up with 3 or 4 applicable techniques.   Drawing up field studies and laboratory data, this paper will discus the importance of conducting screening laboratory and pilot test prior starting up the full scale treatment of a contaminated site with a given technology. For this purpose Rambøll has...... construction of the test unit makes it possible to combine different techniques in order to obtain more aggressive and effective remediation technologies, e.g. UV/ozone or electrochemical/H2O2. Actual case study data is presented to illustrate the benefits of in situ treatability tests prior to full scale...

  4. Security studies

    International Nuclear Information System (INIS)

    Full text: Security studies constitute one of the major tools for evaluating the provisions implemented at facilities to protect and control Nuclear Material against unauthorized removal. Operators use security studies to demonstrate that they are complying with objectives set by the Competent Authority to counter internal or external acts aimed at unauthorized removal of NM. The paper presents the context of security studies carried out in France. The philosophy of these studies is based on a postulated unauthorized removal of NM and the study of the behavior of the systems implemented to control and protect NM in a facility. The potential unauthorized removal of NM usually may take place in two stages. The first stage involves the sequence leading to handling of the NM. It occurs inside the physical barriers of a facility and may include action involving the documents corresponding to Material Control and Accounting systems. At this stage it is possible to limit the risk of unauthorized removal of NM by means of detection capabilities of the MC and A systems. The second stage is more specific to theft and involves removing the NM out of the physical barriers of a facility in which they are being held, notably by affecting the Physical Protection System. Operators have to study, from a quantity and time lapse point of view, the ability of the installed systems to detect unauthorized removal, as well as the possibility of tampering with the systems to mask unlawful operations. Operators have also to analyze the sequences during which NM are accessed, removed from their containment and further removed from the facility in which they are stored. At each stage in the process, the probability of detection and the time taken to carry out the above actions have to be estimated. Of course, these two types of studies complement each other. Security studies have begun, in France, for more than fifteen years. Up to now more than fifty security studies are available in the

  5. Hydrogeological study

    International Nuclear Information System (INIS)

    This work shows the hydrogeological study and well drilling carried out in the Teaching Formation Institute San Jose de Mayo Province Uruguay. It was developed a geological review in the National Directorate of Geology and Mining data base as well as field working, geology and hydrogeology recognition and area well drilling inventory.

  6. Design of an Ultra-Low Noise Analogue Front-End for Fast Voltage Pulses Measurement

    CERN Document Server

    AUTHOR|(SzGeCERN)712364; Arpaia, Pasquale; Cerqueira Bastos, Miguel; Martino, Michele

    2015-01-01

    A 15MS/s, 10 ppm repeatable acquisition system to characterize 3 μs rise-time trapezoidal voltage pulses is proposed. The system is based mainly on a low-noise, 5MHz bandwidth analog front-end. In this paper, the requirements, the concept and physical design are illustrated. Simulation results aimed at assessing the circuit performance are presented. An experimental case study on the characterization of a pulsed power supply for the klystrons modulators of the Compact Linear Collider (CLIC) under study at CERN is reported. In particular, the experimental metrological characterization of the prototype in terms of bandwidth and noise is presented.

  7. Extreme Value Statistical Characterization of Time Domain Pulse-to-Pulse Measurements

    CERN Document Server

    AUTHOR|(SzGeCERN)712364; Arpaia, Pasquale; Martino, Michele

    2015-01-01

    An analytical method, based on Extreme Value Theory (EV T), for predicting the worst case repeatability of time domain pulse-to-pulse measurements, modeled as independent and identically distributed random variables, is proposed. The method allows the use of the noise level of a measurement system for predicting the upcoming peak values over a given number of independent observations. The proposed analytical model is compared against simulated distributions generated in Matlab, highlighting satisfying match for any sample size.The simulations are based on a case study on the characterization of a pulsed power supply for the klystron modulators of the Compact LInear Collider (CLIC) under study at CERN.

  8. Study protocol

    DEFF Research Database (Denmark)

    Thorsteinsson, Troels; Helms, Anne Sofie; Adamsen, Lis;

    2013-01-01

    Background During cancer treatment children have reduced contact with their social network of friends, and have limited participation in education, sports, and leisure activities. During and following cancer treatment, children describe school related problems, reduced physical fitness...... intervention includes an educational program aimed at the child with cancer, the child’s schoolteachers and classmates, and the child’s parents. Children with cancer will each have two ambassadors assigned from their class. The ambassadors visit the child with cancer at the hospital at alternating 2-week......, and one year after the cessation of treatment. The study is powered to quantify the impact of the combined educational, physical, and social intervention programs. Discussion RESPECT is the first population-based study to examine the effect of early rehabilitation for children with cancer, and to use...

  9. Studying Adolescence

    OpenAIRE

    Richter, Linda M.

    2006-01-01

    Young people in their teens constitute the largest age group in the world, in a special stage recognized across the globe as the link in the life cycle between childhood and adulthood. Longitudinal studies in both developed and developing countries and better measurements of adolescent behavior are producing new insights. The physical and psychosocial changes that occur during puberty make manifest generational and early-childhood risks to development, in the form of individual differences in...

  10. Study protocol

    DEFF Research Database (Denmark)

    Madsen, Helle Østergaard; Dam, Ole Henrik; Hageman, Ida

    2012-01-01

    yields a Global Seasonal Score and a prevalence of SAD. Outcomes from the two groups will be compared. Moreover, outcomes from subgroups of the visually impaired population will be compared. ETHICS AND DISSEMINATION: The study is approved by the Danish Data Protection Agency. Results will be published in...... persons with severe visual impairments or blindness and to compare the results to a control group without visual impairments. Moreover, the authors wish to investigate whether SAD is correlated to the degree of impairment or to the diagnosis. METHODS AND ANALYSIS: 2781 persons with visual impairments...

  11. Arctic studies

    International Nuclear Information System (INIS)

    Idaho National Engineering Laboratory (INEL) conducted a study of contamination of the Arctic Ocean and surrounding areas in order to better understand the severity of the problem and identify possible parallels in the United States. The findings were published in a quarterly report as a part of this technical task plan (TTP). While many radioactive and hazardous material contamination sites in this region have been identified, official Russian statements indicate that contaminant concentrations are within normal limits and are currently confined to specific areas

  12. DC Breakdown Experiments with Iridium Cathode

    CERN Document Server

    Profatilova, Iaroslava; Korsback, Anders; Muranaka, Tomoko; Wuensch, Walter

    2015-01-01

    Electrical breakdown occurring in rf accelerating structures is one of the major disruptions of the accelerated beam in CLIC. At CERN, as complements to rf facilities, DC-spark systems have been used to study breakdown properties of many candidate materials for making rf components. In this note, measurements of conditioning speed, breakdown field and field enhancement factor of iridium are presented comparing with previously tested materials. The average breakdown field after conditioning reached 238 MV/m, which places iridium next to copper. By comparison with results and properties of other metals, the low breakdown field of iridium could be explained by its face-centred-cubic crystal structure.

  13. Air temperature stabilization in the thermally isolated optical laboratory

    Science.gov (United States)

    Budagov, J.; Glagolev, V.; Lyablin, M.; Shirkov, G.; Mainaud Durand, H.

    2014-05-01

    For the studies and calibration of optoelectronic components of the high-precision laser based metrology systems the large volume (50 m3) thermoisolated lab based on seismic isolated concrete block is created. The inside lab volume temperature stabilization for the daily observation at 16.5°C is ±0.05°C with ±0.015°C temperature difference between maximal space separated points. This work was initiated by the needs of high-precision alignment of accelerator components of the CLIC, ILC-type colliders.

  14. Linear collider research and development

    International Nuclear Information System (INIS)

    This paper presents a review of work being done on the design of linear colliders with center of mass energies near 0.5 TeV. These include TESLA, SBLC, NLC, JLC, VLEPP, and CLIC. Here the author touches on recent advances made on these designs. Items discussed include advances in the study of beam focusing and spot sizes in setups such as the Final Focus Test Beam, bunching concepts, development of high power RF systems, design of high gradient accelerator structures, and work on emittance features

  15. Doubly charged Higgs from e- γ scattering in the 3-3-1 Model

    Science.gov (United States)

    Cieza Montalvo, J. E.; Ramírez Ulloa, G. H.; Tonasse, M. D.

    2012-11-01

    We studied the production and signatures of doubly charged Higgs bosons in the process γe -→ H -- E +, where E + is a heavy lepton, at the e - e + International Linear Collider (ILC) and CERN Linear Collider (CLIC). The intermediate photons are given by the Weizsäcker-Williams and laser-backscattering distributions. We found that significant signatures are obtained by bremsstrahlung and backward Compton scattering of laser. A clear signal can be obtained for doubly charged Higgs bosons, doubly charged gauge bosons and heavy leptons.

  16. High-energy linear e+e- colliders

    International Nuclear Information System (INIS)

    A description is given of the world-wide efforts in developing e+e- colliders for an energy significantly higher than SLC. The main problem is not to obtain high energy, but to achieve very high luminosity while keeping the power needed within reasonable limits. It turns out that limitations for the final forms (disruption, beam radiation, chromaticity) are leaving little room for choice of machine parameters. Various new acceleration methods are described followed by a more detailed discussion of the approach followed by the CLIC study group at CERN, hopefully to result in a valid 1 TeV + 1 TeV design

  17. Methods for evaluating physical processes in strong external fields at e{sup +}e{sup -} colliders. Furry picture and quasi-classical approach

    Energy Technology Data Exchange (ETDEWEB)

    Porto, Stefano [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Hartin, Anthony [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Moortgat-Pick, Gudrid [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-04-15

    Future linear colliders designs, ILC and CLIC, are expected to be powerful machines for the discovery of Physics Beyond the Standard Model and subsequent precision studies. However, due to the intense beams (high luminosity, high energy), strong electromagnetic fields occur in the beam-beam interaction region. In the context of precision high energy physics, the presence of such strong fields may yield sensitive corrections to the observed electron-positron processes. The Furry picture of quantum states gives a conceptually simple tool to treat physics processes in an external field. A generalization of the quasi-classical operator method (QOM) as an approximation is considered too.

  18. JAS'2000

    CERN Multimedia

    2000-01-01

    Are you interested in beam dynamics? Do you work on the LHC injectors or CLIC or maybe feasibility studies fornew machines? Then this is for youJAS'2000: Joint CERN-Japan-JINR-Russia-US SchoolFrontiers of Accelerator Technology: High Quality Beams to be held on a river boat between St. Petersburg and Moscow 1 to 14 July 2000. For further information see eitherhttp://schools.web.cern.ch/Schools/CAS/ orhttp://www.indiana.edu/~uspas/programs/js/jas2000.html

  19. Conceptual study

    Energy Technology Data Exchange (ETDEWEB)

    Harty, H.

    1978-09-01

    This appendix is a compendium of topical reports prepared for the Hanford Nuclear Energy Center: Status Report: Conceptual Fuel Cycle Studies for the Hanford Nuclear Energy Center; Selection of Heat Disposal Methods for a Hanford Nuclear Energy Center; Station Service Power Supply for a Hanford Nuclear Energy Center (HNEC); Impact of a Hanford Nuclear Energy Center on Ground Level Fog and Humidity; A Review of Potential Technology for the Seismic Characterization of Nuclear Energy Centers; Reliability of Generation at a Hanford Nuclear Energy Center (HNEC); Meteorological Evaluation of Multiple Reactor Contamination Probabilities for a Hanford Nuclear Energy Center; Electric Power Transmission for a Hanford Nuclear Energy Center (HNEC); The Impact of a Hanford Nuclear Energy Center on Cloudiness and Insolation; and A Licensing Review for an HNEC.

  20. Conceptual study

    International Nuclear Information System (INIS)

    This appendix is a compendium of topical reports prepared for the Hanford Nuclear Energy Center: Status Report: Conceptual Fuel Cycle Studies for the Hanford Nuclear Energy Center; Selection of Heat Disposal Methods for a Hanford Nuclear Energy Center; Station Service Power Supply for a Hanford Nuclear Energy Center (HNEC); Impact of a Hanford Nuclear Energy Center on Ground Level Fog and Humidity; A Review of Potential Technology for the Seismic Characterization of Nuclear Energy Centers; Reliability of Generation at a Hanford Nuclear Energy Center (HNEC); Meteorological Evaluation of Multiple Reactor Contamination Probabilities for a Hanford Nuclear Energy Center; Electric Power Transmission for a Hanford Nuclear Energy Center (HNEC); The Impact of a Hanford Nuclear Energy Center on Cloudiness and Insolation; and A Licensing Review for an HNEC

  1. SOCIOLOGICAL STUDIES

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    PAPER Post-Sociology: Exploration and Reflection Xie Lizhong Abstract: "Post-Sociology" refers to a new perspective which is different from tradi- tional perspectives of social studies. "Post-Social History" and "Pluralistic Discourse Analysis" could be seen as its two specific examples. "Discourse Constructivism" and "Pluralism" are the two core concepts of "Post-Sociology". That encouraging people to realize that all "social reality" including our experiences, thoughts and speech are just a "discoursive reality" constructed by social actors under the guidance and constraints of certain discourse system, is the major significance of "PostSociology". Some critics on "Post-Sociology" are misunderstandings, while others couldn't stand to strict analysis.

  2. Aerosol studies

    International Nuclear Information System (INIS)

    As part of the continuing studies of the effects of very severe reactor accidents, an effort was made to develop, test, and improve simple, effective, and inexpensive methods by which the average citizen, using only materials readily available, could protect his residence, himself, and his family from injury by toxic aerosols. The methods for protection against radioactive aerosols should be equally effective against a clandestine biological attack by terrorists. The results of the tests to date are limited to showing that spores of the harmless bacterium, bacillus globegii (BG), can be used as a simulant for the radioactive aerosols. An aerosol generator of Lauterbach type was developed which will produce an essentially monodisperse aerosol at the rate of 109 spores/min. Analytical techniques have been established which give reproducible results. Preliminary field tests have been conducted to check out the components of the system. Preliminary tests of protective devices, such as ordinary vacuum sweepers, have given protection factors of over 1000

  3. Systems studies

    International Nuclear Information System (INIS)

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity, the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the U.S.A. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated Bioenergy Systems (IBS) Activity of IEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the U.S.A. and the U.K. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modelling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from techno-economic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the U.S.A. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review 8 refs, 10 tabs

  4. Systems Studies

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.L.

    1998-03-17

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

  5. Mineralogical studies

    International Nuclear Information System (INIS)

    The mineralogy of WC-series cores from the project area uranium deposit in the San Juan Basin, New Mexico was studied with respect to the deposit and to the paleohydrologic and present hydrologic gradients. Bulk clay analyses, authigenic clay coatings on detrital grains, sulfur minerals, ferric oxide minerals, carbonate minerals, and detrital magnetite-ilmenite were investigated. Among the clays, chlorite/illite seem to offer some indication of the deposit location. More frequent clay coatings are found in the favorable ore horizon along the paleogradient than along the present gradient. Barite is more abundant in the favorable horizon and near ore than elsewhere. Pyrite and other sulfide minerals are relatively sparse in and near the deposit compared to areas away from the deposit. More than two generations of ferric oxide minerals are present in the area and these are deleted in samples nearest ore down the present gradient. Carbonate minerals aremore abundant in lower parts of the favorable zone. 8 figures, 2 tables

  6. Considerations for a QD0 with Hybrid Technology in ILC

    CERN Document Server

    Modena, M; Garcia, H; Gatignon, L; Tomas, R

    2014-01-01

    The baseline design of the QD0 magnet for ILC, the International Linear Collider, is a very compact superconducting quadrupole (coil-dominated magnet). A prototype of this quadrupole is under construction at Brookhaven National Laboratory (USA). In CLIC, the Compact Linear Collider under study at CERN, we are studying a different conceptual solution for the QD0. This is due to two main reasons: all the magnets of the Beam Delivery System will need to be stabilized in the nano-meter range and extremely tight alignment tolerances are required. The proposed solution, now baseline for CLIC, is a room temperature hybrid quadrupole based on resistive coils and permanent magnet blocks (iron-dominated magnet). In this paper we present a conceptual design for a hybrid solution studied and adapted also to the ILC project. A super-ferric solution (superconducting coils with warm iron poles) is proposed to make the cross section compatible with the layout of the experiments. This design matches the compactness requiremen...

  7. Fostering Effective Studying and Study Planning with Study Questions

    Science.gov (United States)

    Wilhelm, Pascal; Pieters, Jules M.

    2007-01-01

    In a course on biological psychology and neuropsychology, study questions were provided that also appeared as test questions in the course exam. This method was introduced to support students in active processing and reproduction of the study texts, and study planning. Data were gathered to test the hypothesis that study question use would be…

  8. Determination of Longitudinal Electron Bunch Lengths on Picosecond Time Scales

    CERN Document Server

    Martínez, C; Calviño, F

    1999-01-01

    At CERN (European Laboratory for Particle Physics) the CLIC (Compact Linear Collider) study is pursuing the design of an electron-positron high-energy linear collider using an innovative concept for the RF (Radio Frequency) power production, the socalled two-beam acceleration scheme. In order to keep the length of the collider in a reasonable range while being able of accelerating electrons and positrons up to 5 TeV, the normal-conducting accelerating structures should operate at very high frequency (in this case 30 GHz). The RF power necessary to feed the accelerating cavities is provided by a second electron beam, the drive beam, running parallel to the main beam. The CLIC Test Facility (CTF) was build with the main aim of studying and demonstrating the feasibility of the two beam acceleration scheme and technology. It is composed of two beams, the drive beam that will generate the 30 GHz RF power and the main beam which will be accelerated by this power. In order to have a good efficiency for the power gen...

  9. Investigations of dc breakdown fields

    CERN Document Server

    Ramsvik, Trond; Reginelli, Alessandra; Taborelli, Mauro

    2006-01-01

    The need for high accelerating gradients for the future 30 GHz multi-TeV e+e- Compact Linear Collider (CLIC) at CERN has triggered a comprehensive study of DC breakdown fields of metals in UHV. The study shows that molybdenum (Mo), tungsten (W), titanium (Ti) and TiVAl reach high breakdown fields, and are thus good candidates for the iris material of CLIC structures. A significant decrease in the saturated breakdown field (Esat) is observed for molybdenum and tungsten when exposed to air. Specifically, at air pressures of 10-5 mbar, the decrease in Esat is found to be 50% and 30% for molybdenum and tungsten, respectively. In addition, a 30% decrease is found when molybdenum is conditioned with a CO pressure of ~1-10-5 mbar. Surface analysis measurements and breakdown conditioning in O2 ambience imply that the origin of the decrease in Esat is closely linked to oxide formation on the cathode surface. "Ex-situ" treatments by ion bombardment of molybdenum effectively reduce the oxide layers, and improve the brea...

  10. Clic en la didáctica: oportunidad de enseñar y aprender mediante experiencia, indagación, reflexión y socialización con apoyo de tecnología

    OpenAIRE

    Galvis, Alvaro

    2004-01-01

    La didáctica es una disciplina y campo de estudio donde se concretan muchos de los esfuerzos de la actividad educativa, donde se ponen en plata blanca los ideales, principios, métodos, criterios y herramientas que permiten al docente asumir la función de enseñar. ¿Cabe repensar la manera de aprender a enseñar, de cara a los requerimientos de la sociedad del conocimiento? ¿Cómo ayudar a que el docente desarrolle criterio y habilidad para tomar decisiones educativas que le permitan asumir la fu...

  11. CLIC- LHC Temelindeki Serbest Elektron Lazer (SEL-Çarpıstırıcısında 40Ar Çekirdeğinin Düşük Enerjili Seviyelerinin İncelenmesi

    Directory of Open Access Journals (Sweden)

    Aynur TATAR

    2009-04-01

    Full Text Available Nükleer Rezonans Floresans (NRF çekirdekte yapısal bozulmalar olusturmadan incelenme imkanı saglayan bir metottur. Bu çalısmalarda kullanılacak ısınımın yüksek kaliteli bir ısınım olması çalısma sonuçları açısından çok önemlidir. Serbest Elektron Lazer (SEL demeti Nükleer Rezonans Floresans (NRF deneyleri için ideal bir kaynaktır. Bu kaynak tek renkli, ayarlanabilir enerjili ve büyük oranda düzeyde kutuplanabilir bir ısınımdır. Large Hadron Collider (LHCdan alınan büyük enerjili çekirdek demetleri ile Serbest Elektron Lazer (SEL demeti uygun bir noktada çarpıstırılacak ve olusan büyük miktardaki olay sayısı çekirdeklerin uyarılma seviyelerini incelemek imkanı saglayacaktır. Argon (40Ar çekirdegi LHC'nin ikinci fazında kullanılacak bir çekirdek olup bu çalısmanın benzerleri ikinci fazda kullanılacak diger çekirdekler ve uygun tüm çekirdekler için de yapılabilir. Bu çalısmada Argon (40Ar çekirdeginin (g, g¢ deneylerinde gözlenmis enerji seviyeleri seçilerek incelenmistir.

  12. PACMAN Project: A New Solution for the High-accuracy Alignment of Accelerator Components

    CERN Document Server

    Mainaud Durand, Helene; Buzio, Marco; Caiazza, Domenico; Catalán Lasheras, Nuria; Cherif, Ahmed; Doytchinov, Iordan; Fuchs, Jean-Frederic; Gaddi, Andrea; Galindo Munoz, Natalia; Gayde, Jean-Christophe; Kamugasa, Solomon; Modena, Michele; Novotny, Peter; Russenschuck, Stephan; Sanz, Claude; Severino, Giordana; Tshilumba, David; Vlachakis, Vasileios; Wendt, Manfred; Zorzetti, Silvia

    2016-01-01

    The beam alignment requirements for the next generation of lepton colliders have become increasingly challenging. As an example, the alignment requirements for the three major collider components of the CLIC linear collider are as follows. Before the first beam circulates, the Beam Position Monitors (BPM), Accelerating Structures (AS)and quadrupoles will have to be aligned up to 10 μm w.r.t. a straight line over 200 m long segments, along the 20 km of linacs. PACMAN is a study on Particle Accelerator Components' Metrology and Alignment to the Nanometre scale. It is an Innovative Doctoral Program, funded by the EU and hosted by CERN, providing high quality training to 10 Early Stage Researchers working towards a PhD thesis. The technical aim of the project is to improve the alignment accuracy of the CLIC components by developing new methods and tools addressing several steps of alignment simultaneously, to gain time and accuracy. The tools and methods developed will be validated on a test bench. This paper pr...

  13. A fast, ultra-low and frequency-scalable power consumption, 10-bit SAR ADC for particle physics detectors

    International Nuclear Information System (INIS)

    The design and measurements results of a fast 10-bit SAR ADC with ultra-low and scalable with frequency power consumption, developed for readout systems for detectors at future particle physics colliders (ILC, CLIC, LHC Upgrade), are described. A prototype ASIC was designed and fabricated in 130 nm CMOS technology and a wide spectrum of static (INL∼<0.5 LSB, DNL∼<0.5 LSB) and dynamic (SINAD ∼58 dB, ENOB∼9.3) measurements was performed to study and quantify the ADC performance. The ADC works in wide 10 kS/s – 40 MS/s sampling frequency range, covering more than three orders of magnitude. In most of the range the power consumption scales linearly with sampling rate with a factor of about 22 μW/MS/s. A dynamic and asynchronous internal logic makes the ADC very well suited not only for commonly used synchronous sampling but also for applications with asynchronous sampling and/or the ones requiring power cycling, like the experiments at future linear collider (ILC/CLIC). The ADC layout is drawn with a small pitch of 146 μm to facilitate multi-channel integration. The obtained figure of Merit is in range 32-37 fJ/conversion for sampling frequencies 10-40 MS/s, placing the ADC among the best State of the Art designs with similar technology and specifications

  14. ECFA Detector R&D Panel, Review Report

    CERN Document Server

    Abramowicz, H; Afanaciev, K.; Aguilar, J.; Alvarez, E.; Bambade, P.; Bortko, L.; Bozovic-Jelisavcic, I.; Castro, E.; Chelkov, G.; Coca, C.; Daniluk, W.; Dragone, A.; Dumitru, L.; Elsener, K.; Emeliantchik, I.; Firu, E.; Fischer, J.; Fiutowski, T.; Ghenescu, V.; Gostkin, M.; Grzelak, G.; Haller, G.; Henschel, H.; Ignatenko, A.; Idzik, M.; Ito, K.; Kananov, S.; Kielar, E.; Kollowa, S.; Kotula, J.; Krumstein, Z.; Krupa, B.; Kulis, S.; Lange, W.; Levy, A.; Levy, I.; Linssen, L.; Lohmann, W.; Lukic, S.; Moron, J.; Moszczynski, A.; Nauenberg, U.; Neagu, A.; Novgorodova, O.; Nuiry, F.X.; Ohlerich, M.; Orlandea, M.; Oleinik, G.; Oliwa, K.; Olshevski, A.; Pandurovic, M.; Pawlik, B.; Preda, T.; Przyborowski, D.; Sato, Y.; Sadeh, I.; Sailer, A.; Schumm, B.; Schuwalow, S.; Schwartz, R.; Smiljanic, I.; Swientek, K.; Takubo, Y.; Teodorescu, E.; Wierba, W.; Yamamoto, H.; Zawiejski, L.; Zgura, T.S.; Zhang, J.

    2014-01-01

    Two special calorimeters are foreseen for the instrumentation of the very forward region of an ILC or CLIC detector; a luminometer (LumiCal) designed to measure the rate of low angle Bhabha scattering events with a precision better than 10−3 at the ILC and 10−2 at CLIC, and a low polar-angle calorimeter (BeamCal). The latter will be hit by a large amount of beamstrahlung remnants. The intensity and the spatial shape of these depositions will provide a fast luminosity estimate, as well as determination of beam parameters. The sensors of this calorimeter must be radiation-hard. Both devices will improve the e.m. hermeticity of the detector in the search for new particles. Finely segmented and very compact electromagnetic calorimeters will match these requirements. Due to the high occupancy, fast front-end electronics will be needed. Monte Carlo studies were performed to investigate the impact of beam-beam interactions and physics background processes on the luminosity measurement, and of beamstrahlung on th...

  15. dc breakdown conditioning and breakdown rate of metals and metallic alloys under ultrahigh vacuum

    CERN Document Server

    Descoeudres, A; Calatroni, S; Taborelli, M; Wuensch, W

    2009-01-01

    RF accelerating structures of the Compact Linear Collider (CLIC) require a material capable of sustaining high electric field with a low breakdown rate and low induced damage. Because of the similarity of many aspects of DC and RF breakdown, a DC breakdown study is underway at CERN in order to test candidate materials and surface preparations, and have a better understanding of the breakdown mechanism under ultra-high vacuum in a simple setup. Conditioning speeds and breakdown fields of several metals and alloys have been measured. The average breakdown field after conditioning ranges from 100 MV/m for Al to 850 MV/m for stainless steel, and is around 170 MV/m for Cu which is the present base-line material for CLIC structures. The results indicate clearly that the breakdown field is limited by the cathode. The presence of a thin cuprous oxide film at the surface of copper electrodes significantly increases the breakdown field. On the other hand, the conditioning speed of Mo is improved by removing oxides at t...

  16. Conceptual Design of the Drive Beam for a PWFA-LC

    Energy Technology Data Exchange (ETDEWEB)

    Pei, S.; Hogan, M.J.; Raubenheimer, T.O.; Seryi, A.; /SLAC; Braun, H.H.; Corsini, R.; Delahaye, J.P.; /DESY

    2009-08-03

    Plasma Wake-Field Acceleration (PWFA) has demonstrated acceleration gradients above 50 GeV/m. Simulations have shown drive/witness bunch configurations that yield small energy spreads in the accelerated witness bunch and high energy transfer efficiency from the drive bunch to the witness bunch, ranging from 30% for a Gaussian drive bunch to 95% for bunch with triangular shaped longitudinal profile. These results open the opportunity for a linear collider that could be compact, efficient and more cost effective than the present microwave technologies. A concept of a PWFA-based Linear Collider (PWFA-LC) has been developed by the PWFA collaboration. Here we will describe the conceptual design and optimization of the drive beam, which includes the drive beam linac and distribution system. We apply experience of the CLIC drive beam design and demonstration in the CLIC Test Facility (CTF3) to this study. We discuss parameter optimization of the drive beam linac structure and evaluate the drive linac efficiency in terms of the drive beam distribution scheme and the klystron/modulator requirements.

  17. A multi-TeV compact e+e- linear collider

    International Nuclear Information System (INIS)

    The CLIC study of a high energy (0.5-5 TeV), high luminosity (1034-1035 cm-2 sec-1) e± linear collider is presented. Beam acceleration using high frequency (30 GHz) normal-conducting structures operating at high accelerating fields (150 MV/m) significantly reduces the length and, in consequence, the cost of the linac. Based on new beam and linac parameters derived from a recently developed set of general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. The drive beam generation scheme for RF power production by the so-called ''Two Beam Acceleration (TBA)'' method is described. It uses a thermionic gun and a fully-loaded normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches, and RF multiplication by funnelling in compressor rings to produce the desired bunch structure. Recent 30 GHz hardware developments and results from the CLIC Test Facility (CTF), assessing the feasibility of the scheme, are described

  18. Case Study: Writing a Journal Case Study

    Science.gov (United States)

    Prud'homme-Genereux, Annie

    2016-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue describes incorporating a journal article into the classroom by first converting it into a case study.

  19. Ecological baseline studies

    Science.gov (United States)

    Vickers, D.

    1980-01-01

    Environmental studies of Merritt Island are discussed. Five areas of the island's ecology are examined. They include: a terrestrial community analyses, a plant community study, a small mammal population study, a rainfall study, and an ichthyological analyses.

  20. Building Transdisciplinary Environmental Studies

    DEFF Research Database (Denmark)

    Holm, Jesper

    Conceptual analytical-methodological conceptualization of crossdisciplinary sustainability studies......Conceptual analytical-methodological conceptualization of crossdisciplinary sustainability studies...

  1. After 16 years of service, the LEP Pre-Injector (LPI) was finally closed down at Easter. The LPI was not only one of the essential building blocks of LEP, but it also supplied beams to a whole host of experiments.

    CERN Multimedia

    2001-01-01

    In the coming months it will undergo extensive work to be converted into a test facility for CLIC, one of the possible options for a future accelerator. So in the autumn of 2001, the LPI zone will be re-baptised CTF3 (CLIC Test Facility 3).

  2. German Studies in America. German Studies Notes.

    Science.gov (United States)

    Sander, Volkmar; Osterle, Heinz D.

    This volume contains two papers, "German Studies in America," by Volkmar Sander, and "Historicism, Marxism, Structuralism: Ideas for German Culture Courses," by Heinz D. Osterle. The first paper discusses the position of German studies in the United States today. The greatest challenge comes from low enrollments; therefore, German departments must…

  3. Connecting the interstellar magnetic field at the heliosphere to the Loop I superbubble

    CERN Document Server

    Frisch, P C; Funsten, H O; Magalhaes, A M; McComas, D J; Piirola, V; Schwadron, N A; Seriacopi, D B; Wiktorowicz, S J

    2014-01-01

    The local interstellar magnetic field affects both the heliosphere and the surrounding cluster of interstellar clouds (CLIC). Measurements of linearly polarized starlight provide the only test of the magnetic field threading the CLIC. Polarization measurements of the CLIC magnetic field show multiple local magnetic structures, one of which is aligned with the magnetic field traced by the center of the "ribbon" of energetic neutral atoms discovered by the Interstellar Boundary Explorer (IBEX). Comparisons between the bulk motion of the CLIC through the local standard of rest, the magnetic field direction, the geometric center of Loop I, and the polarized dust bridge extending from the heliosphere toward the North Polar Spur direction all suggest that the CLIC is part of the rim region of the Loop I superbubble.

  4. Connecting the interstellar magnetic field at the heliosphere to the Loop I superbubble

    Science.gov (United States)

    Frisch, P. C.; Berdyugin, A.; Funsten, H. O.; Magalhaes, A. M.; McComas, D. J.; Piirola, V.; Schwadron, N. A.; Seriacopi, D. B.; Wiktorowicz, S. J.

    2015-01-01

    The local interstellar magnetic field affects both the heliosphere and the surrounding cluster of interstellar clouds (CLIC). Measurements of linearly polarized starlight provide the only test of the magnetic field threading the CLIC. Polarization measurements of the CLIC magnetic field show multiple local magnetic structures, one of which is aligned with the magnetic field traced by the center of the "ribbon" of energetic neutral atoms discovered by the Interstellar Boundary Explorer (IBEX). Comparisons between the bulk motion of the CLIC through the local standard of rest, the magnetic field direction, the geometric center of Loop I, and the polarized dust bridge extending from the heliosphere toward the North Polar Spur direction all suggest that the CLIC is part of the rim region of the Loop I superbubble.

  5. Connecting the interstellar magnetic field at the heliosphere to the Loop I superbubble

    International Nuclear Information System (INIS)

    The local interstellar magnetic field affects both the heliosphere and the surrounding cluster of interstellar clouds (CLIC). Measurements of linearly polarized starlight provide the only test of the magnetic field threading the CLIC. Polarization measurements of the CLIC magnetic field show multiple local magnetic structures, one of which is aligned with the magnetic field traced by the center of the ''ribbon'' of energetic neutral atoms discovered by the Interstellar Boundary Explorer (IBEX). Comparisons between the bulk motion of the CLIC through the local standard of rest, the magnetic field direction, the geometric center of Loop I, and the polarized dust bridge extending from the heliosphere toward the North Polar Spur direction all suggest that the CLIC is part of the rim region of the Loop I superbubble

  6. Wakefield Monitor Experiments with X-Band Accelerating Structures

    CERN Document Server

    Lillestøl, Reidar; Corsini, Roberto; Döbert, Steffen; Farabolini, Wilfrid; Malina, Lukas; Pfingstner, Juergen; Wuensch, Walter

    2015-01-01

    The accelerating structures for CLIC must be aligned with a precision of a few um with respect to the beam trajectory in order to mitigate emittance growth due to transverse wake fields. We report on first results from wake field monitor tests in an X-band structure, with a probe beam at the CLIC Test Facility. The monitors are currently installed in the CLIC Two-Beam Module. In order to fully demonstrate the feasibility of using wakefield monitors for CLIC, the precision of the monitors must be verified using a probe beam while simultaneously filling the structure with high power rf used to drive the accelerating mode. We outline plans to perform such a demonstration in the CLIC Test Facility.

  7. Case Study Teaching

    Science.gov (United States)

    Herreid, Clyde Freeman

    2011-01-01

    This chapter describes the history of case study teaching, types of cases, and experimental data supporting their effectiveness. It also describes a model for comparing the efficacy of the various case study methods. (Contains 1 figure.)

  8. Chemical Industry Bandwidth Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-12-01

    The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

  9. Esophagram (Barium Swallow Study)

    Science.gov (United States)

    ... esophagram is a study that is completed in radiology. The test evaluates the esophagus. The esophagus is ... to wear. The study is completed in a radiology (x-ray/fluoroscopy) room. If a child is ...

  10. Tailored Barium Swallow Study

    Science.gov (United States)

    ... View Denver Pollen Count You are here: Programs & Services > Tests We Offer > Imaging Tests Tailored Barium Swallow Study The TBS is a special study that is completed in radiology. The test evaluates the mouth and the throat ...

  11. The Study of Algae

    Science.gov (United States)

    Rushforth, Samuel R.

    1977-01-01

    Included in this introduction to the study of algae are drawings of commonly encountered freshwater algae, a summary of the importance of algae, descriptions of the seven major groups of algae, and techniques for collection and study of algae. (CS)

  12. Current Research Studies

    Science.gov (United States)

    ... Home > Explore CCFA Research > Current Research Studies Current Research Studies Email Print + Share The Crohn’s & Colitis Foundation ... online. Learn more about CCFA Partners. CCFA Clinical Research Alliance The Clinical Research Alliance is a network ...

  13. Future Circular Collider Study

    CERN Document Server

    Benedikt, Michael

    2014-01-01

    This presentation has been given during the 1st EuCARD-2 annual meeting. It contains: • Motivation & scope • Parameters & design challenges • Study organization, study time line • Preparing global FCC collaboration • Summary

  14. Excellence in Social Studies.

    Science.gov (United States)

    Durfee, David A.

    1986-01-01

    Discusses a strategy for unifying and improving the social studies curriculum through an "outcomes sought" approach. Outlines eight measurable qualities students completing social studies should have achieved. Discusses implications of this approach. (LP)

  15. FEMA DFIRM Study Info

    Data.gov (United States)

    Minnesota Department of Natural Resources — This table contains details about the study such as the study name, datum, projection, etc. There is normally only one record in this table for each Flood Insurance...

  16. 522 Postmarket Surveillance Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The 522 Postmarket Surveillance Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated under section 522 of the...

  17. Post-Approval Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a...

  18. Satellite servicing economic study

    Science.gov (United States)

    1990-01-01

    Previous studies have shown that satellite servicing is cost effective; however, all of these studies were of different formats, dollar year, learning rates, availability, etc. Therefore, it was difficult to correlate any useful trends from these studies. The reviewed study was initiated to correlate the economic data into a common data base, using a common set of assumptions. A selected set of existed funded programs was then analyzed to provide an independent analysis of the servicing options and potential economic benefits.

  19. CISSP study guide

    CERN Document Server

    Conrad, Eric; Feldman, Joshua; Riggins, Kevin

    2011-01-01

    "The Eleventh Hour CISSP Study Guide" is keyed to the latest CISSP exam. This book is streamlined to include only core certification information and is presented for ease of last-minute studying. Main objectives of the exam are covered concisely with key concepts highlighted. This is the only guide you need for last-minute studying. This title answers the toughest questions and highlights core topics. This title can be paired with any other study guide so you are completely prepared.

  20. Medicinsk forbedring: study drugs

    OpenAIRE

    Holm Sørensen, Camilla; Juul Asmussen, Melanie; Constantin, Liv; Haugtved, Claire Rigmor

    2015-01-01

    This study investigates medical optimization regarding cognitive enhancement. Study drugs are performance-enhancing drugs that people use in terms of optimizing cognitive skills. The use of study drugs has turned out to have a beneficial effect when it comes to perform in stressful situations for example an examination. The purpose of our project is to analyze central arguments for and against the use of study drugs. We analyze two arguments for and three arguments that express a statem...

  1. Implementation of manufacturing data management application in the scientific research project. Case: CERN, the European Organization for Nuclear Research

    CERN Document Server

    Saifoulina, Margarita

    2010-01-01

    This Bachelor’s thesis examined the implementation process of an MTF (Manufacturing and Test Folder) application in the CLIC (Compact Linear Collider) Radio Frequency Structure Development project for manufacturing data management purposes. The primary goal of the study was to investigate how MTF implementation and its integration with CERN EDMS (Engineering and Equipment Data Management System) system could facilitate product life cycle through the supply chain, and could affect on manufacturing operations performance in internaland external levels. The aim of the study was also to find out implementation differences within CERN (European Organization for Nuclear Research) projects. The study is divided into two parts: a qualitative theory section and an empirical section. In the theory section differences of features between PDM (Product Data Management), EDM (Engineering Data Management) and PLM (Product Life Cycle Management) systems were studied. The thesis examined the benefits and managerial challeng...

  2. Social Psychoanalytic Disability Studies

    Science.gov (United States)

    Goodley, Dan

    2011-01-01

    This paper explores connections and tensions between psychoanalysis and disability studies. The first part of the paper considers contemporaneous engagements with the psyche by a number of disability studies writers. These scholars have remained accountable to a politicised disability studies but have pushed for critical encounters with the…

  3. Defining (Conceptualizing) Social Studies.

    Science.gov (United States)

    Shaver, James P.

    1990-01-01

    Critiques James Barth, Robert Barr, and Sam Shermis' three social studies traditions theory and National Commission on Social Studies task force report. Argues first falsely splits essential social studies components; second creates a curricular hodgepodge. Highlights need to consider values as both affective and cognitive and to create…

  4. System studies and applications

    International Nuclear Information System (INIS)

    Extensive information is given for each of the following topics: (1) fusion reactor studies, (2) reactor concepts, (3) first wall studies, (4) laser system studies, (5) fusion-fission hybrids, (6) National security applications, and (7) long-range planning for inertial confinement fusion

  5. Studying Engineering Practice

    DEFF Research Database (Denmark)

    Buch, Anders

    2015-01-01

    The study of engineering practices has been the focus of Engineering Studies over the last three decades. Theses studies have used ethnographic and grounded methods in order to investigate engineering practices as they unfold in natural settings - in workplaces and engineering education. However,...

  6. Fusion reactor studies

    International Nuclear Information System (INIS)

    A review is given of fusion reactor systems studies, the objectives of these studies are outlined and some recent conceptual reactor designs are described. The need for further studies in greater depth is indicated so that progress towards a commercial fusion reactor may be consolidated. (U.K.)

  7. Studying to Learn.

    Science.gov (United States)

    Air Univ., Maxwell AFB, AL.

    This booklet was prepared in response to a demand from Air Force Officers returning to academic study after being out of school for several years. Its main purpose is to help returning veterans learn how to study. The guide is divided into three sections: (1) the "Reconnaissance-Read-Recall" (RRR) system of study, (2) concepts in "How We Learn,"…

  8. Study deep geothermal energy; Studie dypgeotermisk energi

    Energy Technology Data Exchange (ETDEWEB)

    Havellen, Vidar; Eri, Lars Sigurd; Andersen, Andreas; Tuttle, Kevin J.; Ruden, Dorottya Bartucz; Ruden, Fridtjof; Rigler, Balazs; Pascal, Christophe; Larsen, Bjoern Tore

    2012-07-01

    The study aims to analyze the potential energy with current technology, challenges, issues and opportunities for deep geothermal energy using quantitative analysis. It should especially be made to identify and investigate critical connections between geothermal potential, the size of the heating requirements and technical solutions. Examples of critical relationships may be acceptable cost of technology in relation to heating, local geothermal gradient / drilling depth / temperature levels and profitability. (eb)

  9. Mysore study: A study of suicide notes

    OpenAIRE

    Namratha, P.; Kishor, M.; Sathyanarayana Rao, T. S.; Raman, Rajesh

    2015-01-01

    Background: Suicide is one of the leading causes of preventable deaths. Recent data suggest South India as one of the regions with highest suicide rates in the world. In 2013, 134,799 people committed suicide in India according to the statistics released by the National Crime Records Bureau. Suicide note is one of the most important sources to understand suicide, which may be beneficial in suicide prevention. Studies on suicidal notes from this part of the world are sparse. Objective: The aim...

  10. Function of chloride intracellular channel 1 in gastric cancer cells

    Directory of Open Access Journals (Sweden)

    Bo-Pei Li

    2012-01-01

    Full Text Available AIM: To investigate the effect of chloride intracellular channel 1 (CLIC1 on the cell proliferation, apoptosis, migration and invasion of gastric cancer cells. METHODS: CLIC1 expression was evaluated in human gastric cancer cell lines SGC-7901 and MGC-803 by real time polymerase chain reaction (RT-PCR. Four segments of small interference RNA (siRNA targeting CLIC1 mRNA and a no-sense control segment were designed by bioinformatics technology. CLIC1 siRNA was selected using Lipofectamine 2000 and transfected transiently into human gastric cancer SGC-7901 and MGC-803 cells. The transfected efficiency was observed under fluorescence microscope. After transfection, mRNA expression of CLIC1 was detected with RT-PCR and Western blotting was used to detect the protein expression. Proliferation was examined by methyl thiazolyl tetrazolium and apoptosis was detected with flow cytometry. Polycarbonate membrane transwell chamber and Matrigel were used for the detection of the changes of invasion and migration of the two cell lines. RESULTS: In gastric cancer cell lines SGC-7901 and MGC-803, CLIC1 was obviously expressed and CLIC1 siRNA could effectively suppress the expression of CLIC1 protein and mRNA. Proliferation of cells transfected with CLIC1 siRNA3 was enhanced notably, and the highest proliferation rate was 23.3% (P = 0.002 in SGC-7901 and 35.55% (P = 0.001 in MGC-803 cells at 48 h. The G2/M phase proportion increased, while G0/G1 and S phase proportions decreased. The apoptotic rate of the CLIC1 siRNA3 group obviously decreased in both SGC-7901 cells (62.24%, P = 0.000 and MGC-803 cells (52.67%, P = 0.004. Down-regulation of CLIC1 led to the inhibition of invasion and migration by 54.31% (P = 0.000 and 33.62% (P = 0.001 in SGC-7901 and 40.74% (P = 0.000 and 29.26% (P = 0.002 in MGC-803. However, there was no significant difference between the mock group cells and the negative control group cells. CONCLUSION: High CLIC1 expression can efficiently

  11. Function of chloride intracellular channel 1 in gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Peng-Fei Ma; Jun-Qiang Chen; Zhen Wang; Jin-Lu Liu; Bo-Pei Li

    2012-01-01

    AIM:To investigate the effect of chloride intracellular channel 1 (CLIC1) on the cell proliferation,apoptosis,migration and invasion of gastric cancer cells.METHODS:CLIC1 expression was evaluated in human gastric cancer cell lines SGC-7901 and MGC-803 by real time polymerase chain reaction (RT-PCR).Four segments of small interference RNA (siRNA) targeting CLIC1 mRNA and a no-sense control segment were designed by bioinformatics technology.CLIC1 siRNA was selected using Lipofectamine 2000 and transfected transiently into human gastric cancer SGC-7901 and MGC-803 cells.The transfected efficiency was observed under fluorescence microscope.After transfection,mRNA expression of CLIC1 was detected with RT-PCR and Western blotting was used to detect the protein expression.Proliferation was examined by methyl thiazolyl tetrazolium and apoptosis was detected with flow cytometry.Polycarbonate membrane transwell chamber and Matrigel were used for the detection of the changes of invasion and migration of the two cell lines.RESULTS:In gastric cancer cell lines SGC-7901 and MGC-803,CLIC1 was obviously expressed and CLIC1 siRNA could effectively suppress the expression of CLIC1 protein and mRNA.Proliferation of cells transfected with CLIC1 siRNA3 was enhanced notably,and the highest proliferation rate was 23.3% (P =0.002) in SGC-7901 and 35.55% (P =0.001) in MGC-803 cells at 48 h.The G2/M phase proportion increased,while G0/G1 and S phase proportions decreased.The apoptotic rate of the CLIC1 siRNA3 group obviously decreased in both SGC-7901 cells (62.24%,P =0.000) and MGC-803 cells (52.67%,P =0.004).Down-regulation of CLIC1 led to the inhibition of invasion and migration by 54.31% (P =0.000) and 33.62% (P =0.001) in SGC-7901 and 40.74% (P =0.000) and 29.26% (P =0.002) in MGC-803.However,there was no significant difference between the mock group cells and the negative control group cells.CONCLUSION:High CLIC1 expression can efficiently inhibit proliferation and

  12. Advanced Clothing Studies

    Science.gov (United States)

    Orndoff, Evelyne; Poritz, Darwin

    2014-01-01

    All human space missions require significant logistical mass and volume that add an unprecedented burden on longduration missions beyond low-Earth orbit. For these missions with limited cleaning resources, a new wardrobe must be developed to reduce this logistical burden by reducing clothing mass and extending clothing wear. The present studies have been undertaken, for the first time, to measure length of wear and to assess the acceptance of such extended wear. Garments in these studies are commercially available exercise T-shirts and shorts, routine-wear T-shirts, and longsleeved pullover shirts. Fabric composition (cotton, polyester, light-weight, superfine Merino wool, modacrylic, cotton/rayon, polyester/Cocona, modacrylic/Xstatic, modacrylic/rayon, modacrylic/lyocell/aramid), construction (open knit, tight knit, open weave, tight weave), and finishing treatment (none, quaternary ammonium salt) are the independent variables. Eleven studies are reported here: five studies of exercise T-shirts, three of exercise shorts, two of routine wear Tshirts, and one of shirts used as sleep-wear. All studies are conducted in a climate-controlled environment, similar to a space vehicle's. For exercise clothing, study participants wear the garments during aerobic exercise. For routine wear clothing, study participants wear the T-shirts daily in an office or laboratory. Daily questionnaires collected data on ordinal preferences of nine sensory elements and on reason for retiring a used garment. Study 1 compares knitted cotton, polyester, and Merino exercise T-shirts (61 participants), study 2, knitted polyester, modacrylic, and polyester/Cocona exercise T-shirts (40 participants), study 3, cotton and polyester exercise shorts, knitted and woven (70 participants), all three using factorial experimental designs with and without a finishing treatment, conducted at the Johnson Space Center, sharing study participants. Study 4 compares knitted polyester and ZQ Merino exercise T

  13. American Studies in Turkey

    OpenAIRE

    Gülriz Buken

    2006-01-01

    In the discipline of American Studies in Turkey, the major contribution emanates, on the one hand, from the American Culture and Literature Departments instituted in various Universities in Turkey and, on the other, from the American Studies Association of Turkey. Up till now, unfortunately, no Research and Performance Institute or Center for the Study of America has yet been established to secure the necessary contacts with other similar institutions in Europe and in the United States, to fa...

  14. Standardization Study of Ghritas

    OpenAIRE

    D. Shaila; M. K. Santosh; Chandrakumar, T.; I. Sanjeeva Rao

    2004-01-01

    The standardization of ghritas such as amritaprasa ghrita, brahmi ghrita, chagalyadi ghrita and phala ghrita has been studied. These ghritas are the important Ayurvedic formulations used for peri-natal care of mother and child health. Standardization of ghritas were achieved by organoleptic study, physico-chemical analysis, qualitative analysis, thin layer chromatography (TLC), UV - visible spectrophotometry and high performance liquid chromatographic (HPLC) fingerprint studies. Qualitative a...

  15. Single Policy Study

    DEFF Research Database (Denmark)

    Kronsell, Annica; Manners, Ian James

    Single policy studies are the most common form of European Union (EU) research. Single policy studies are widely used to understand the role of the EU in a wide variety of sectors, together with their development over time, and often offer public policy prescriptions. This chapter discusses the...... relevance of single policy studies in EU research and give examples of how such research can be designed and carried out. The chapter reviews three examples of single policy studies using different methods based on EU environmental policy, the EU biofuels directive, and the EU Common Security and Defence...

  16. School library user studies

    Directory of Open Access Journals (Sweden)

    Zdenka Verlič

    2002-01-01

    Full Text Available The analysis of the results of a questionnaire answered by Slovene primary and secondary school librarians is presented in the article. The purpose of the study was to determine if library user studies were being performed in our school libraries. It was confirmed that more studies had been conducted by school librarians with a completed higher level of education, by librarians with adequate (library and information sciences education and also by the librarians participating in life-long learning in their professional field than by other librarians. An important factor influencing increased user studies was also librarians’ membership in the Slovene librarian professional organization.

  17. Why Study in Australia?

    Institute of Scientific and Technical Information of China (English)

    丁丽丽

    2014-01-01

    Going overseas to pursue further studies is even more generalized in recent years. Students are open to a variety of op-tions to decide which country to go and which university to choose. Why wouldn’t you want to study with some of the best minds in the world? Australia is a leading global education power, with world’s best educators and facilities. It also provides both local and international students with a variety of quality study options. This essay presents some of the important reasons why in-ternational students should study in Australia in regard to education quality, affordable fees, government support, multiple cultures and immigration policies.

  18. Studies on seismic waves

    Institute of Scientific and Technical Information of China (English)

    张海明; 陈晓非

    2003-01-01

    The development of seismic wave study in China in the past four years is reviewed. The discussion is divided into several aspects, including seismic wave propagation in laterally homogeneous media, laterally heterogeneous media, anisotropic and porous media, surface wave and seismic wave inversion, and seismic wave study in prospecting and logging problems. Important projects in the current studies on seismic wave is suggested as the development of high efficient numerical methods, and applying them to the studies of excitation and propagation of seismic waves in complex media and strong ground motion, which will form a foundation for refined earthquake hazard analysis and prediction.

  19. Contemporary American Chinese Studies

    Institute of Scientific and Technical Information of China (English)

    Qiu Huafei

    2008-01-01

    The rise of modern American scholarship on China was largely attributed to the establishment of the American Joint Committee on Contemporary China (JCCC) in 1959 which sponsored all kinds of activities to promote Chinese studies, ranging from institutional support and financial resources to training courses. Since then, American study of China has entered into a period of sustainability that features academic and group-oriented research. It has become a mainstream discipline in American social science studies.1 There are some distinctive differences between early sinology and modern Chinese Studies: the latter is much more concentrated on the study of issues, comparative historical studies, and contemporary Chinese society. American Chinese studies stresses empirical research, textual data, and the application of theory to practice.Shanghai. He was a Fulbright visiting professor at State University of New York at Geneseo from 2006-2007. This treatise is one of a series of studies for China's National Research Foundation of Philosophy and Social Science (05BGJ012), "American Chinese Studies."

  20. Study Groups in Denmark

    DEFF Research Database (Denmark)

    Hjorth, Poul G.

    2007-01-01

    Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions.......Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions....

  1. Human exploration mission studies

    Science.gov (United States)

    Cataldo, Robert L.

    1989-01-01

    The Office of Exploration has established a process whereby all NASA field centers and other NASA Headquarters offices participate in the formulation and analysis of a wide range of mission strategies. These strategies were manifested into specific scenarios or candidate case studies. The case studies provided a systematic approach into analyzing each mission element. First, each case study must address several major themes and rationale including: national pride and international prestige, advancement of scientific knowledge, a catalyst for technology, economic benefits, space enterprise, international cooperation, and education and excellence. Second, the set of candidate case studies are formulated to encompass the technology requirement limits in the life sciences, launch capabilities, space transfer, automation, and robotics in space operations, power, and propulsion. The first set of reference case studies identify three major strategies: human expeditions, science outposts, and evolutionary expansion. During the past year, four case studies were examined to explore these strategies. The expeditionary missions include the Human Expedition to Phobos and Human Expedition to Mars case studies. The Lunar Observatory and Lunar Outpost to Early Mars Evolution case studies examined the later two strategies. This set of case studies established the framework to perform detailed mission analysis and system engineering to define a host of concepts and requirements for various space systems and advanced technologies. The details of each mission are described and, specifically, the results affecting the advanced technologies required to accomplish each mission scenario are presented.

  2. Information society studies

    CERN Document Server

    Duff, Alistair S

    2013-01-01

    We are often told that we are ""living in an information society"" or that we are ""information workers."" But what exactly do these claims mean, and how might they be verified? In this important methodological study, Alistair S. Duff cuts through the rhetoric to get to the bottom of the ""information society thesis."" Wide-ranging in coverage, this study will be of interest to scholars in information science, communication and media studies and social theory. It is a key text for the newly-unified specialism of information society studies, and an indispensable guide to the future of this disc

  3. Project management case studies

    CERN Document Server

    Kerzner, Harold R

    2013-01-01

    A new edition of the most popular book of project management case studies, expanded to include more than 100 cases plus a ""super case"" on the Iridium Project Case studies are an important part of project management education and training. This Fourth Edition of Harold Kerzner''s Project Management Case Studies features a number of new cases covering value measurement in project management. Also included is the well-received ""super case,"" which covers all aspects of project management and may be used as a capstone for a course. This new edition:Contains 100-plus case studies drawn from re

  4. Research Studies & Networks

    Science.gov (United States)

    These epidemiological studies may assist in evaluating associations between certain pharmaceuticals and disease risk and contain detailed information on pharmaceutical use and disease risk, including cancer.

  5. Prolactinomas : clinical studies

    NARCIS (Netherlands)

    Kars, Marleen

    2008-01-01

    Prolactinoma are treated with dopamine agonists, which are effective in reducing prolactin and tumor size. Studies reporting clinical and radiological outcome are scarce. The study described in chapter 2, assesses long-term outcome in patients treated with dopamine agonists for macroprolactinoma. An

  6. Independent Human Studies.

    Science.gov (United States)

    Kaplan, Suzanne; Wilson, Gordon

    1978-01-01

    The Independent Human Studies program at Schoolcraft College offers an alternative method of earning academic credits. Students delineate an area of study, pose research questions, gather resources, synthesize the information, state the thesis, choose the method of presentation, set schedules, and take responsibility for meeting deadlines. (MB)

  7. Fusion energy studies

    International Nuclear Information System (INIS)

    Current experimental efforts are aimed toward developing cryosorption vacuum pumps for removing unburned fuel and impurities from the plasma, studying deep-bed sorption pumps for roughing and transfer operations, investigating methods for recovery of tritium bred in blankets of lithium or lithium alloys, and studying containment of tritium that permeates metal walls

  8. CDC's Cervical Cancer Study

    Science.gov (United States)

    ... in Cancer Moonshot Stay Informed CDC’s Cervical Cancer Study Language: English Español (Spanish) Recommend on Facebook Tweet ... year. As part of CDC’s Cervical Cancer (Cx3) Study, we surveyed a sample of both health care ...

  9. Simulation in International Studies

    Science.gov (United States)

    Boyer, Mark A.

    2011-01-01

    Social scientists have long worked to replicate real-world phenomena in their research and teaching environments. Unlike our biophysical science colleagues, we are faced with an area of study that is not governed by the laws of physics and other more predictable relationships. As a result, social scientists, and international studies scholars more…

  10. Home Study Advertising Handbook.

    Science.gov (United States)

    Lambert, Michael P., Ed.; Welch, Sally R., Ed.

    This handbook contains a collections of nine articles on the subject of direct-response advertising. The handbook gives advice on how to create effective advertisements for home study courses. The nine articles are the following: "Overview of Home Study Advertising in the 1990s" (Michael P. Lambert); "Ad Features that Sell" (Nancie E. Robertson);…

  11. EAL studying texts

    CERN Document Server

    Napthin, Melanie

    2013-01-01

    EAL: Studying texts has been developed out of Insight's best-selling ESL English for Year 12, which has helped thousands of ESL/ EAL students to achieve top marks. Offering comprehensive coverage of Area of Study 1: Reading and responding in VCE English, the book takes a highly practical approach that builds students' skills progressively.

  12. A Social Studies Imperative.

    Science.gov (United States)

    Engle, Shirley H.

    1985-01-01

    Despite all the technology at educators' disposal, the field of social studies is more uncertain of its goals and more intellectually confused than ever before. The failure to deal in a rigorous and uncluttered way with current social problems is one of the most unconscionable defects in the social studies today. (RM)

  13. Entrepreneurship and Process Studies

    DEFF Research Database (Denmark)

    Hjorth, Daniel; Holt, Robin; Steyaert, Chris

    2015-01-01

    variable as just that, a variable. The resonance with entrepreneurship studies is obvious. If any field is alive to, and fully resonant with, a processual understanding of, for example, the creation of firms, it is entrepreneurship studies. This special issue is an attempt to consider the promise and...

  14. What Are Sleep Studies?

    Science.gov (United States)

    ... Events Spokespeople Email Alerts E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory Committees Contact Us FAQs Home » Health Information for the Public » Health Topics » Sleep Studies Explore Sleep Studies What Are... Types Who Needs ...

  15. Spacing Studies in Peppers

    Science.gov (United States)

    Higher plant stand densities usually result in greater pepper fruit yields. While the impact of stand density on yield has been studied for bell and non-bell peppers, but very little information exists regarding implications on pesticide efficacy. The objective of these studies was to determine th...

  16. English Intonation Studies.

    Science.gov (United States)

    Lewis, Jack Windsor

    This paper is a critical survey of the work of various linguists in the field of English intonation studies. Crystal's work is cited as being particularly influential in the author's work. It is argued that there is a lack of progress in this field because of a preoccupation on the part of scholars with their own studies and their application and…

  17. Theorizing Iberian Studies

    Science.gov (United States)

    Newcomb, Robert Patrick

    2015-01-01

    A growing number of scholars invested in Iberian Studies are asking how peninsular literary and cultural studies might be reimagined, and reinvigorated, by placing the Spanish and Portuguese canons into critical dialogue with each other, and with Galician, Catalan, Basque/Euskadi, and Latin American and North African immigrant writers, cultural…

  18. Building Transdisciplinary Environmental Studies

    DEFF Research Database (Denmark)

    Holm, Jesper

    department (Dept. of Environment, Technology and Social Studies, Roskilde University), and has originally in another version been presented in the book “Miljøregulering - tværvidenskabelige studier (Environmental Regulation. Interdisciplinary Studies)” (Holm, Kjærgård & Pedersen eds. 1997, in Danish) written...

  19. The CAIRO4 study

    DEFF Research Database (Denmark)

    de Wilt, Johannes H W; Verhoef, Cornelis; Punt, Cornelis J A;

    2016-01-01

    stages of the disease. We here propose a randomized trial in order to demonstrate that resection of the primary tumour improves overall survival. METHODS/DESIGN: The CAIRO4 study is a multicentre, randomized, phase III study of the Dutch Colorectal Cancer Group (DCCG). Patients with synchronous...

  20. The CAIRO4 study

    DEFF Research Database (Denmark)

    't Lam-Boer, Jorine; Mol, Linda; Verhoef, Cornelis;

    2015-01-01

    stages of the disease. We here propose a randomized trial in order to demonstrate that resection of the primary tumour improves overall survival. METHODS/DESIGN: The CAIRO4 study is a multicentre, randomized, phase III study of the Dutch Colorectal Cancer Group (DCCG). Patients with synchronous...

  1. Managerial Accounting. Study Guide.

    Science.gov (United States)

    Plachta, Leonard E.

    This self-instructional study guide is part of the materials for a college-level programmed course in managerial accounting. The study guide is intended for use by students in conjuction with a separate textbook, Horngren's "Accounting for Management Control: An Introduction," and a workbook, Curry's "Student Guide to Accounting for Management…

  2. Luminescence study of spodumene

    International Nuclear Information System (INIS)

    A comparative study is made of the luminescence of five kinds of spodumene from Minas Gerais, Brazil, studied previously by optical absorption spectroscopy. Natural gemstones are used which, in the course of the experiments, were irradiated with X-rays. (L.C.)

  3. Studies of Personality Disorders

    DEFF Research Database (Denmark)

    Ronningstam, Elsa; Simonsen, Erik; Oldham, John M; Maffei, Cesare; Gunderson, John; Chanen, Andrew M; Millon, Theodore

    2014-01-01

    The past 25 years have shown major advances in the studies of personality disorders. This collaborative article by the presidents, past and present, of ISSPD reflects on the progress within several significant areas of studies, i.e., assessment, neuroscience, treatment, prevention, advocacy, and...

  4. Study Groups in Denmark

    DEFF Research Database (Denmark)

    Hjorth, Poul G.

    2007-01-01

    Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions....

  5. MY ENGLISH STUDY

    Institute of Scientific and Technical Information of China (English)

    孙岩; Roxanne; Lees

    2003-01-01

    I am a student of Yanshan University, majoring in English. I have studied English for a long time, which is full of (and have encountered some) special experiences (in my studies). After graduation from (a) junior (middle) school, I did not go to senior (middle) school for

  6. Soil organic matter studies

    International Nuclear Information System (INIS)

    The use of isotopes in soil organic matter studies is reviewed. Such studies include measuring the input of organic carbon into soils, the decomposition of isotope-labelled materials such as organic compounds and microbial and plant material in soils, the characterization of soil organic matter and the availability of nutrients released from organic residues. (U.K.)

  7. Danish Rural Eye Study

    DEFF Research Database (Denmark)

    Høeg, Tracy Beth; Ellervik, Christina; Buch, Helena;

    2016-01-01

    PURPOSE: To examine the frequency and causes of visual impairment (VI) in a select population of Danish adults. METHODS: A total of 3843 adults aged 20-94 years from the Danish General Suburban Population Study (GESUS) were included in the population-based, cross-sectional ophthalmological study,...

  8. Critical Digital Tourism Studies

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia; Munar, Ana María

    2013-01-01

    This paper advocates the need for a critical and cross-disciplinary research agenda on the field of digital technologies and tourism. The changing virtual landscape of tourism has received increased attention by tourism scholars. However, contemporary studies on information technologies (IT) are...... studying digital socio-technical systems and virtual mediation in tourism. Critical Digital Tourism Studies opens a new cross-disciplinary field where the sociality of virtual tourism interactions is examined (entailing the study of structures, social rules, ideologies, power relations, sustainability...... approached mostly from a business administration perspective and informed by conceptual frameworks developed in management and marketing. IT studies in tourism are still at a stage similar to the first advocacy phase of tourism research in general (Jafari, 1990) and are seldom inspired by relevant...

  9. Subsurface geochemical studies

    International Nuclear Information System (INIS)

    Subsurface geochemical studies are composed of spectral radiometric studies and core geochemistry. These studies are aimed at identifying both secondary and remnant primary halos pertinent to the known mineralization. Genetically, any geochemical signatures delineated in the altered rocks are classified as epigenetic dispersion patterns that are formed during post primary-mineralization processes. However, a few remnant hypogene geochemical dispersion patterns, typical of immobile elements, are also manifested in the area. The above-mentioned studies are also oriented towards understanding the genesis of uranium deposits in granitic rocks. Thus these geochemical studies form an essential link in the exploration systems approach to the identification of halos and contribute to drilling plans and the ultimate discovery of blind uranium deposits in granitic rocks. 61 figures, 5 tables

  10. Design of a 50 MW 30 GHz gyroklystron amplifier for accelerator applications

    CERN Document Server

    Blank, M; Cauffman, S; Felch, K; Mizuhara, Y M; Lawson, W

    2002-01-01

    Summary form only given. The results of a study performed by CPI for CERN are described below. The purpose of the work was to design a pulsed 30 GHz, 50 MW gyroklystron amplifier to be used for testing and conditioning Compact Linear Collider (CLIC) mainline accelerating structures. The specifications for the amplifier are listed. The technical risk factors and achievable performance for several distinct configurations, including coaxial and cylindrical cavities interacting at the fundamental and second harmonic of the cyclotron frequency, were investigated in the study. Following detailed physics designs of several different circuits and electron guns, a fundamental TE/sub 011/ coaxial mode configuration was selected as the most likely to achieve the specifications. Design details and performance predictions for this configuration are given.

  11. ±25ppm repeatable measurement of trapezoidal pulses with 5MHz bandwidth

    CERN Document Server

    AUTHOR|(SzGeCERN)712364; Arpaia, Pasquale; Cerqueira Bastos, Miguel; Martino, Michele

    2015-01-01

    High-quality measurements of pulses are nowadays widely used in fields such as radars, pulsed lasers, electromagnetic pulse generators, and particle accelerators. Whilst literature is mainly focused on fast systems for nanosecond regime with relaxed metrological requirements, in this paper, the high-performance measurement of slower pulses in microsecond regime is faced. In particular, the experimental proof demonstration for a 15 MS/s,_25 ppm repeatable acquisition system to characterize the flat-top of 3 ms rise-time trapezoidal pulses is given. The system exploits a 5MHz bandwidth circuit for analogue signal processing based on the concept of flat-top removal. The requirements, as well as the conceptual and physical designs are illustrated. Simulation results aimed at assessing the circuit performance are also presented. Finally, an experimental case study on the characterization of a pulsed power supply for the klystrons modulators of the Compact Linear Collider (CLIC) under study at CERN is reported. In ...

  12. R&D for Future Accelerators

    CERN Document Server

    Zimmermann, Frank

    2006-01-01

    Research & development for future accelerators are reviewed. First, I discuss colliding hadron beams, in particular upgrades to the Large Hadron Collider (LHC). This is followed by an overview of new concepts and technologies for lepton ring colliders, with examples taken from VEPP-2000, DAFNE-2, and Super-KEKB. I then turn to recent progress and studies for the multi-TeV Compact Linear Collider (CLIC). Some generic linear-collider research, centered at the KEK Accelerator Test Facility, is described next. Subsequently, I survey the neutrino factory R&D performed in the framework of the US feasibility study IIa, and I also comment on a novel scheme for producing monochromatic neutrinos from an electron-capture beta beam. Finally, I present innovative ideas for a high-energy muon collider and I consider recent experimental progress on laser and plasma acceleration.

  13. Tyhjiövalokaarien mallintaminen: plasman syttymisestä pintavuorovaikutuksiin

    CERN Document Server

    Timko, Helga; Djurabekova, Flyura; Schneider, Ralf; Matyash, Konstantin; Calatroni, Sergio; Taborelli, Mauro; Wuensch, Walter

    2011-01-01

    A better understanding of vacuum arcs is desirable in many of today's 'big science' projects including linear colliders, fusion devices, and satellite systems. For the Compact Linear Collider (CLIC) design, radio-frequency (RF) breakdowns occurring in accelerating cavities influence efficiency optimisation and cost reduction issues. Studying vacuum arcs both theoretically as well as experimentally under well-defined and reproducible direct-current (DC) conditions is the first step towards exploring RF breakdowns. In this thesis, we have studied Cu DC vacuum arcs with a combination of experiments, a particle-in-cell (PIC) model of the arc plasma, and molecular dynamics (MD) simulations of the subsequent surface damaging mechanism. We have also developed the 2D ARC-PIC code and the physics model incorporated in it, especially for the purpose of modelling the plasma initiation in vacuum arcs. Assuming the presence of a field emitter at the cathode initially, we have identified the conditions for plasma formation...

  14. China's India Studies

    Institute of Scientific and Technical Information of China (English)

    Liu Qian

    2008-01-01

    Over the past 50 years, with the improvement of relationship between India and China, the scope of India studies in China's IR research has been broadened and the new areas of studies are being explored. The research agenda of India studies has already extended to the areas like economy, society, culture, security, national strategy and their impact on both bilateral and international relations. In this situation, the focuses of India studies in China's IR research can be mainly identified as follows: reviews on India's social, political and economic systems; analysis on the national strategy and foreign policy; Sino-Indian relations; India's relations with some international organizations. However, even though many fresh progresses have been made in India studies, the India studies in China's IR research still lag far behind the study of other important countries like the U.S., UK, Russia and Japan, and more problems and challenges will face in the coming future. The paper believes that a fuller understanding of India probably will not make China and India close friends, but it definitely will help to prevent them from becoming fierce enemies.

  15. STUDY ON CHRONIC LYMPHEDEMA

    Directory of Open Access Journals (Sweden)

    Aromal Chekavar

    2014-03-01

    Full Text Available INTRODUCTION: Little attention has been given to the impact of long standing lymphedema and its complications. AIM: The aim of the study was to prepare a profile of long standing lymphedema complications PATIENTS AND METHODS: A total of 88 patients with lymphedema were included in this hospital based descriptive study. The study was designed to include age, sex, etiology, duration, prophylaxis and complications observed in each patient and entered into a proforma separately. RESULTS: A total of 88 cases studied, 74 cases are lower limb and 14 cases are upper limb lymphedema. Among 74 cases of lower limb lymphedema 4 cases occurred after inguinal lymphadenectomy and upper limb lypmhedema are secondary to postmodified radical mastectomy. A total of 40 cases in 88 patients had complications of lymphedema, among 88 cases studied 54 male and 34 were female patients 29 patients had cellulitis 3 patients had infected ulcer with maggots and 1 patient had lymphoma, among 88 patients 50 patients was on regular benzathine pencillin prophylaxis. Incidence of complications is 37.5 percent and incidence of complication in patient on penicillin prophylaxis 28.4 percent. Our study does not show no significant statistical correlation between benzathine prophylaxis and occurrence of complications. (pvalue0.727. CONCLUSION: The study provided relevant information about complications of lymphoedema, Pencillin prophylaxis is not found effective in reducing recurrent cellulitis episodes in chronic lymphedema. In our series we found one case of lymphoma (Diffuse large cell lymphoma developing in lymphedematous tissue of lower limb.

  16. Effective Physics Study Habits

    Science.gov (United States)

    Zettili, Nouredine

    2011-04-01

    We discuss the methods of efficient study habits and how they can be used by students to help them improve learning physics. In particular, we deal with ideas pertaining to the most effective techniques needed to help students improve their physics study skills. These ideas were developed as part of Project IMPACTSEED (IMproving Physics And Chemistry Teaching in SEcondary Education), an outreach grant funded by the Alabama Commission on Higher Education. This project is motivated by a major pressing local need: A large number of high school physics teachers teach out of field. In the presentation, focus on topics such as the skills of how to develop long term memory, how to improve concentration power, how to take class notes, how to prepare for and take exams, how to study scientific subjects such as physics. We argue that the student who conscientiously uses the methods of efficient study habits will be able to achieve higher results than the student who does not; moreover, a student equipped with the proper study skills will spend much less time to learn a subject than a student who has no good study habits. The underlying issue here is not the quantity of time allocated to the study efforts by the student, but the efficiency and quality of actions. This work is supported by the Alabama Commission on Higher Education as part of IMPACTSEED grant.

  17. Study of copper fluorination

    International Nuclear Information System (INIS)

    This report deals with the action of fluorine on copper. Comprehensive descriptions are given of the particular technological methods and of the preparation of the reactants. This fluorination reaction has been studied at medium and low fluorine pressures. A nucleation and growth phenomenon is described. The influence of a pollution of the gas phase on the fluorination process is described. The solid-state reaction between cupric fluoride and cooper has also been studied. A special study has been made of the growth of copper deposits by thermal decomposition of gaseous fluorides. (author)

  18. Studying Voltage Transformer Ferroresonance

    Directory of Open Access Journals (Sweden)

    Hamid Radmanesh

    2012-09-01

    Full Text Available This study studies the effect of Circuit Breaker Shunt Resistance (CBSR, Metal Oxide Vaistor (MOV and Neutral earth Resistance (NR on the control of ferroresonance in the voltage transformer. It is expected that NR can controlled ferroresonance better than MOV and CBSR. Study has been done on a one phase voltage transformer rated 100 VA, 275 kV. The simulation results reveal that considering the CBSR and MOV exhibits a great mitigating effect on ferroresonance overvoltages, but these resistances cannot control these phenomena for all range of parameters. By applying NR to the system structure, ferroresonance has been controlled and its amplitude has been damped for all parameters values.

  19. Motivations of parametric studies

    International Nuclear Information System (INIS)

    The paper concerns the motivations of parametric studies in connection with the Programme for the Inspection of Steel Components PISC II. The objective of the PISC II exercise is to evaluate the effectiveness of current and advanced NDT techniques for inspection of reactor pressure vessel components. The parametric studies were initiated to determine the influence of some parameters on defect detection and dimensioning, and to increase the technical bases of the Round Robin Tests. A description is given of the content of the parametric studies including:- the effect of the defects' characteristics, the effect of equipment characteristics, the effect of cladding, and possible use of electromagnetic techniques. (U.K.)

  20. American Studies in Romania

    Directory of Open Access Journals (Sweden)

    Ioana Luca

    2006-01-01

    Full Text Available American Studies at the University of BucharestThe idea of teaching American Studies and founding a program in American Studies was first voiced in the long meetings of faculty and students held at the University of Bucharest soon after the collapse of the communist regime. The proposal was one of many that reflected the spirit of reform and hope for radical changes at the outset of Romania’s transition to democracy. The absence of institutional structures other than English departments and t...

  1. Thyroid function study

    International Nuclear Information System (INIS)

    A short revision of thyroid physiology is done. The radioisotopes of common use in thyroid investigation and the choice of the most appropriated ones are discussed. A table showing radioisotopes frequently used in this study, with their main characteristics is presented. Among several isotopic assays in thyroid propaedeutics, those that refer to the function study, topographic studies and tests 'in vitro' are pointed out. Exploration methods 'in vivo' are treated, such as: thyroid uptake; urinary excretion; thyroid scintigraphy, with scintigraphic imagings; stimulation test by TSH; suppression test; pbi; clearance test with perchlorate; iodine deficiency test and thyroid study with technetium. 'In vitro' proofs like triiodothyronine (T3) and thyroxine (T4) assays, as well as free thyroxine index, are treated. At last, the therapeutics by Iodine 131 is commented and emphasis is given to its application on the treatment of hyperthyroidism and thyroid carcinoma

  2. Pavement Subgrade Performance Study

    DEFF Research Database (Denmark)

    Zhang, Wei; Ullidtz, Per; Macdonald, Robin

    1998-01-01

    The report describes the second test in the Danish Road Testing Machine (RTM) under the International Pavement Subgrade Performance Study. Pavement response was measured in different layers, and compared to different theroretical values. Performance in terms of plastic strains, rutting...

  3. PPB | Study Team

    Science.gov (United States)

    The Pleuropulmonary Blastoma (PPB) DICER1 Syndrome Study team is made up of researchers from the National Cancer Institute, Children¹s National Medical Center, the International Pleuropulmonary Blastoma Registry, and Washington University in St. Louis.

  4. The Black Studies Boondoggle

    Science.gov (United States)

    Long, Richard A.

    1970-01-01

    Indicates tendencies dangerous to the basic purpose of Black Studies, and identifies four external challeges--imperialism, paternalism, nihilism, and materialism. An internal challenge is considered to be the use of European and Establishment constructs to analyze black reality. (DM)

  5. The Study of Matter.

    Science.gov (United States)

    Campbell, Peter

    2000-01-01

    Reviews the booklet "The Study of Matter" produced by the Institute of Physics as part of their Shaping the Future series. This booklet is designed for teachers of chemistry, physics, design and technology, and biology. (Author/CCM)

  6. Czech Studies. Language

    Czech Academy of Sciences Publication Activity Database

    Papcunová, Jana

    Leeds: Maney Publ, 2008 - ( Parkinson , S.; Barber, L.), s. 869-882 ISBN 978-1-905981-82-3 Institutional research plan: CEZ:AV0Z90610518 Keywords : linguistics * bibliography * Czech studies Subject RIV: AI - Linguistics

  7. Czech studies : language

    Czech Academy of Sciences Publication Activity Database

    Nováková, Marie; Papcunová, Jana

    Vol. 66. Leeds: Maney Publ., 2006 - ( Parkinson , S.; Barber, L.), s. 761-773 ISBN 978-1-904350-26-2 Institutional research plan: CEZ:AV0Z90610518 Keywords : linguistics * bibliography * Czech studies Subject RIV: AI - Linguistics

  8. Czech Studies. Language

    Czech Academy of Sciences Publication Activity Database

    Nováková, Marie; Papcunová, Jana

    London: Maney Publishing, 2005 - ( Parkinson , S.; Barber, L.), s. 789-799 ISBN 0-901286-94-X Institutional research plan: CEZ:AV0Z90610518 Keywords : linguistics * bibliography * Czech studies Subject RIV: AI - Linguistics

  9. Czech Studies. Language

    Czech Academy of Sciences Publication Activity Database

    Nováková, Marie; Papcunová, Jana

    London: Maney Publishing, 2001 - ( Parkinson , S.), s. 867-878 ISBN 0-901286-94-X R&D Projects: GA AV ČR KSK8002119 Keywords : bibliography * Czech linguistics Subject RIV: AF - Documentation, Librarianship, Information Studies

  10. Czech studies : language

    Czech Academy of Sciences Publication Activity Database

    Nováková, Marie; Papcunová, Jana

    Vol. 67. Leeds: Maney Publ., 2007 - ( Parkinson , S.; Barber, L.), s. 813-825 ISBN 978-1-904350-95-8 Institutional research plan: CEZ:AV0Z90610518 Keywords : linguistics * bibliography * Czech studies Subject RIV: AI - Linguistics

  11. Geomembrane special study

    International Nuclear Information System (INIS)

    The objective of the Geomembrane Special Study was to asses the suitability of geomembranes in Uranium Mill Tailings Remedial Action (UMTRA) Project pile designs. Geomembranes, also called flexible membrane liners, are made of polymer resins and are thermoplastic materials. Part of the special study was to evaluate regulatory compliance and acceptability issues. This study was proposed because of the extensive use of geomembranes in hazardous waste site remedial actions and their accepted use in Resource Conservation and Recovery Act (RCRA) cells as both covers and liners to limit infiltration, or as part of leachate collection systems. This study has reviewed the recent geomembrane literature focusing on: (1) longevity; (2) performance; (3) constructibility; and (4) quality control/quality assurance considerations. In addition to these technical considerations, regulatory compliance and acceptability concerns were also evaluated. This report describes the results of the literature review, including correspondence with manufacturers, resin producers, experts in the field, and long-term major users. 12 refs., 2 tabs

  12. Mobile OS Comparative Study

    OpenAIRE

    Joseph, Jyothy; K, Shinto Kurian

    2013-01-01

    In the fast growing mobile revolutionary era, many operating systems are playing vital role in present market. This study is intending to identify the apt and secure mobile based on mobile operating systems capability and user requirements.

  13. Applied Research Study

    Science.gov (United States)

    Leach, Ronald J.

    1997-01-01

    The purpose of this project was to study the feasibility of reusing major components of a software system that had been used to control the operations of a spacecraft launched in the 1980s. The study was done in the context of a ground data processing system that was to be rehosted from a large mainframe to an inexpensive workstation. The study concluded that a systematic approach using inexpensive tools could aid in the reengineering process by identifying a set of certified reusable components. The study also developed procedures for determining duplicate versions of software, which were created because of inadequate naming conventions. Such procedures reduced reengineering costs by approximately 19.4 percent.

  14. Progress in Aridification Studies

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ A national key project entitled "Predictive study of aridification in northern China in association with life-supporting environment changes" has recently passed the appraisal of a panel organized by the Ministry of Science & Technology in Beijing.

  15. Videofluoroscopic Swallowing Study (VFSS)

    Science.gov (United States)

    ... have already had a swallowing test with a speech-language pathologist, also called an SLP. During this test you ... Other resources ASHA documents about VFSS Guidelines for Speech-Language Pathologists Performing Videofluoroscopic Swallowing Studies Knowledge and Skills Needed ...

  16. HYDROGEOLOGIC CASE STUDIES

    Science.gov (United States)

    Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

  17. Accelerator research studies

    International Nuclear Information System (INIS)

    This progress report for the Accelerator Research Studies program at the University of Maryland covers the second year (June 1, 1989 to May 31, 1990) of the current three-year contract period from June 1, 1988 to May 31, 1991, funded by the Department of Energy under Contract No. AC05-85ER40216. The research program is divided into three separate tasks, as follows: the study of Transport and Longitudinal Compression of Intense, High-Brightness Beams; the study of Collective Ion Acceleration by Intense Electron Beams and Pulse-Powered Plasma Focus; the study of Microwave Sources and Parameter Scaling for High-Frequency Linacs. This report consists of three sections in which the progress for each task is documented separately. An introduction and synopsis is presented at the beginning of the progress report for each task

  18. Techno-economic Study

    DEFF Research Database (Denmark)

    Sigurdsson, Halldór Matthias; Point, J.C.; Million, P.

    A techno-economic model for analysing and comparing broadband deployment strategies has been established. The resulting simulation model can compare Capital Expenditure (CAPEX) of dominating broadband technologies in different types of demographic areas. The study reveals the competitiveness and...

  19. The Hi Five study

    DEFF Research Database (Denmark)

    Johansen, Anette; Denbæk, Anne Maj; Bonnesen, Camilla Thørring;

    2015-01-01

    BACKGROUND: Infectious illnesses such as influenza and diarrhea are leading causes of absenteeism among Danish school children. Interventions in school settings addressing hand hygiene have shown to reduce the number of infectious illnesses. However, most of these studies include small populations...... and almost none of them are conducted as randomized controlled trials. The overall aim of the Hi Five study was to develop, implement and evaluate a multi-component school-based intervention to improve hand hygiene and well-being and to reduce the prevalence of infections among school children...... randomized multi-component school-based hand hygiene intervention is the first to include education on healthy and appropriate toilet behavior as part of the curriculum. No previous studies have involved supplementary cleaning at the school toilets as an intervention component. The study will have the added...

  20. Comparative Packaging Study

    Science.gov (United States)

    Perchonok, Michele; Antonini, David

    2008-01-01

    This viewgraph presentation describes a comparative packaging study for use on long duration space missions. The topics include: 1) Purpose; 2) Deliverables; 3) Food Sample Selection; 4) Experimental Design Matrix; 5) Permeation Rate Comparison; and 6) Packaging Material Information.