1471000 20180328104355.0 oai:cds.cern.ch:1471000 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN CERN EDS CLAS1 SzGeCERN Accelerators and Storage Rings PREPRINT Brüning, O CERN Rossi, L CERN High Luminosity Large Hadron Collider A description for the European Strategy Preparatory Group CERN LHC Not applicable CERN PREPRINT 000725169CER evelyne.delucinge@cern.ch CERN-ATS-2012-236 The Large Hadron Collider (LHC) is the largest scientific instrument ever built. It has been exploring the new energy frontier since 2009, gathering a global user community of 7,000 scientists. It will remain the most powerful accelerator in the world for at least two decades, and its full exploitation is the highest priority in the European Strategy for Particle Physics, adopted by the CERN Council and integrated into the ESFRI Roadmap. To extend its discovery potential, the LHC will need a major upgrade around 2020 to increase its luminosity (rate of collisions) by a factor of 10 beyond its design value. As a highly complex and optimized machine, such an upgrade of the LHC must be carefully studied and requires about 10 years to implement. The novel machine configuration, called High Luminosity LHC (HL-LHC), will rely on a number of key innovative technologies, representing exceptional technological challenges, such as cutting-edge 13 tesla superconducting magnets, very compact and ultra-precise superconducting cavities for beam rotation, new technology for beam collimation and 300-metre-long high-power superconducting links with zero energy dissipation. HL-LHC federates efforts and R&D of a large community towards the ambitious HL-LHC objectives and contributes establishing the European Research Area (ERA) as a focal point of global research cooperation and a leader in frontier knowledge and technologies. However, it relies on a strong participation from outside the (ERA), in particular leading US and Japanese laboratories, which will facilitate the implementation of the construction phase as a global project. The proposed governance model is tailored accordingly and may pave the way for the organization of other global research infrastructures. Preprint CC-BY-3.0 Preprint CERN 2012 n 201231 23 p ATS The project is partially supported by the EC as FP7 HiLumi LHC Design Study under grant no. 284404 Collaboration http://cds.cern.ch/record/1471000/files/CERN-ATS-2012-236.pdf http://cds.cern.ch/record/1471000/files/CERN-ATS-2012-236.pdf?subformat=pdfa pdfa 2012 Geneva CERN 01 Aug 2012 eng 11 PUBLIC 1470601 20240223164758.0 CERN EDS CLAS1 Baglin, V CERN Bregliozzi, G CERN Jimenez, J M CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable 000725128CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-229 During the year 2011 the LHC operated for 682 fills, meaning 247 days and 2 hours of stable beam in total. From 368 bunches per beam at 150 ns bunch spacing circulating in the ring in December 2010, the 2011 proton physic ended with 1380 bunches per beam circulating with 50 ns bunch spacing. The machine performances increased in parallel with the vacuum improvement thanks to a well performed scrubbing run in April 2011 and a continuous conditioning of the beam pipes while the machine was running. The 2011 LHC operation ended with one month of ions physic runs. During the machine operation various phenomena of beam - vacuum interaction were detected, analyzed and solved. This paper describes the pressure behaviour along the machine layout and mainly in specific components position like the TDI (Target Dump Injection) and the MKI injector kickers. The “pressure spike” phenomena near the experiment CMS and in some Dipole 1 (D1) regions are discussed. Finally, results obtained during the 25 ns machine developments are presented. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS WEPPD018 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470601/files/CERN-ATS-2012-229.pdf http://cds.cern.ch/record/1470601/files/CERN-ATS-2012-229.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/WEPPD018.pdf Published version from JaCoW LHC Beam Vacuum During 2011 Machine Operation oai:cds.cern.ch:1470601 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Lanza, G CERN eng 1445554 2534 neworleans20120520 PUBLIC 1470600 20240223164758.0 CERN EDS CLAS1 Caspers, F CERN Edwards, P CERN Holz, M CERN Taborelli, M CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable 000725127CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-228 Electron cloud in particle accelerators can be mitigated by coating the vacuum beam pipe with thin films of low secondary electron yield (SEY). SEY of small samples can be measured in the laboratory. Verifying the performance of long pipes is more complex, since it requires their insertion in the accelerator and the subsequent measurement of the beam induced pressure rise. RF induced multipacting in a coaxial waveguide configuration is proposed as a test before insertion in the machine. The technique is applied to two main bending dipoles of the SPS, where the RF power is fed through a tungsten wire stretched along the vacuum chamber (6.4 m). A dipole with a bare stainless steel chamber shows a clear power threshold initiating an abrupt rise in reflected power and pressure. The effect is enhanced at RF frequencies corresponding to cyclotron resonances for given magnetic fields. Preliminary results show that the dipole with a carbon coated vacuum chamber does not exhibit any pressure rise or reflected RF power up to the maximum available input power. In the event of a large scale coating production this technique will be a valuable resource for quality control. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS MOPPC009 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470600/files/CERN-ATS-2012-228.pdf http://cds.cern.ch/record/1470600/files/CERN-ATS-2012-228.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/MOPPC009.pdf Published version from JaCoW Multipactor for e-cloud diagnostics oai:cds.cern.ch:1470600 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Costa Pinto, P CERN eng 1445554 139 neworleans20120520 PUBLIC 1470599 20240223164758.0 CERN EDS CLAS1 Bregliozzi, G CERN Lanza, G CERN Baglin, V CERN Jimenez, J M CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable 000725126CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-227 In the CERN Large Hadron Collider (LHC), about 6 km of the UHV beam pipe are at room temperature and serve as experimental or utility insertions. TiZrV non-evaporable getter (NEG) coating is used to maintain the design pressure during beam operation. Molecular desorption due to dynamic effects is stimulated during protons operation at high intensity. This phenomenon produces an important gas load from the vacuum chamber walls, which could lead to a partial or total saturation of the NEG coating. To keep the design vacuum performances and to schedule technical interventions for NEG reactivation, it is necessary to take into account all these aspects and to regularly evaluate the saturation level of the NEG coating. Experimental studies of a typical LHC vacuum sector were conducted in the laboratory in order to identify the best method to assess the saturation level of the beam pipe. Partial saturation of the NEG was performed and the effective pumping speed, transmission and capture probability are analysed. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS WEPPD015 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470599/files/CERN-ATS-2012-227.pdf http://cds.cern.ch/record/1470599/files/CERN-ATS-2012-227.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/WEPPD015.pdf Published version from JaCoW Saturation behaviour of the LHC NEG coated beam pipes oai:cds.cern.ch:1470599 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Porcelli, T CERN eng 1445554 2525 neworleans20120520 PUBLIC 1470598 20240223164758.0 CERN EDS CLAS1 ARTICLE ConferencePaper Garion, C CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable CERN ARTICLE 000725125CER shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-226 An unexpected gas inrush in a vacuum chamber leads to the development of a fast pressure wave. It carries small particles that can compromise functionality of sensitive machine systems such as the RF cavities or kickers. In the LHC machine, it has been proposed to protect this sensitive equipment by the installation of fast vacuum valves. The main requirements for the fast valves and in particular for the blade are: fast closure in the 20 ms range, high transparency and melting temperature in case of closure with beam in, dust free material to not contaminate sensitive adjacent elements, and last but not least vacuum compatibility and adequate leak tightness across the blade. In this paper, different designs based on a vitreous carbon blade are presented and a solution is proposed. The main reasons for this material choice are given. The mechanical study of the blade behaviour under dynamic forces is shown. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings 4 p ATS WEPPD016 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470598/files/CERN-ATS-2012-226.pdf http://cds.cern.ch/record/1470598/files/CERN-ATS-2012-226.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/WEPPD016.pdf Published version from JaCoW Development of Glassy Carbon Blade for LHC Fast Vacuum Valve oai:cds.cern.ch:1470598 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Coly, P CERN eng 13 1445554 2528 neworleans20120520 PUBLIC 1470597 20240223164758.0 CERN EDS CLAS1 Lacroix, A CERN Rambeau, H CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable 000725124CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-225 RF contact fingers are primarily used as a transition element to absorb the thermal expansion of vacuum chambers during bake-out and also to compensate for mechanical tolerances. They have to carry the beam image current to avoid the generation of Higher Order Modes and to reduce beam impedances. They are usually made out of copper beryllium thin sheets and are therefore very fragile and critical components. In this paper, a robust design based on a deformable finger concept is proposed. It allows the compensation of large longitudinal movements and also defaults such as transverse offset, twist or bending. The concept of this new RF fingers is first explained, then the design of the component is presented. The mechanical study based on a highly non-linear Finite Element model is shown as well as preliminary tests, including fatigue assessment, carried out on prototypes. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS WEPPD017 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470597/files/CERN-ATS-2012-225.pdf http://cds.cern.ch/record/1470597/files/CERN-ATS-2012-225.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/WEPPD017.pdf Published version from JaCoW Development of a New RF Finger concept for vacuum beam line interconnections oai:cds.cern.ch:1470597 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Garion, C CERN eng 1445554 2531 neworleans20120520 PUBLIC 1470582 20240223164758.0 CERN EDS CLAS1 Chaure, J CERN Cruikshank, P CERN Gallagher, J CERN Garion, C CERN Jimenez, J M CERN Kersevan, R CERN Kos, H CERN Leduc, L CERN Lepeule, P CERN Provot, N CERN Rambeau, H CERN Veness, R CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable 000725120CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-223 The LHC has ventured into unchartered territory for Particle Physics accelerators. A dedicated consolidation program is required between 2013 and 2014 to ensure optimal physics performance. The experiments, ALICE, ATLAS, CMS, and LHCb, will utilise this shutdown, along with the gained experience of three years of physics running, to make optimisations to their detectors. New vacuum technologies have been developed for the experimental areas, to be integrated during this first phase shutdown. These technologies include bellows, vacuum chambers and ion pumps in aluminium, new beryllium vacuum chambers, and composite mechanical supports. An overview of this first phase consolidation program for the LHC experiments is presented. publication CC-BY JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS WEPPD025 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470582/files/CERN-ATS-2012-223.pdf http://cds.cern.ch/record/1470582/files/CERN-ATS-2012-223.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/WEPPD025.pdf Published version from JaCoW LHC Detector Vacuum System Consolidation for Long Shutdown 1 (LS1) in 2013-2014 oai:cds.cern.ch:1470582 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN Inspire 1124727 2012 Gallilee, M CERN eng 1445554 2555 neworleans20120520 PUBLIC 1470581 20241025033557.0 ARTICLE ConferencePaper Faus-Golfe, A Valencia U., IFIC Barnes, M J CERN Toral, F CIEMAT, Madrid Podadera, I CIEMAT, Madrid Belver-Aguilar, C Valencia U., IFIC CERN-ATS-2012-222 CLIC Not applicable CERN ARTICLE 000725119CER shauna.dillon@cern.ch CLIC Pre-Damping Rings (PDR) and Damping Rings (DR) are required for reducing the emittance of the electron and positron beams before being accelerated in the main linac. Several stripline kicker systems are used to inject and extract the beam from the PDR and DR. Wake fields produced by the charged particles passing through the aperture of the stripline kickers may become an important source of emittance growth; for this reason, simulations of longitudinal and transverse beam impedance in the frequency domain, and their equivalent in the time domain are needed. First analytical approaches, future simulations and tests planned are presented in this paper. CC-BY publication JACoW CERN EDS CLAS1 CLIC-Note CLICARCHIVE SzGeCERN Accelerators and Storage Rings n 201231 a2012 CLIC-Note-978 4 p ATS TUPPR018 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR018.pdf Published version from JaCoW 656785 1541386 http://cds.cern.ch/record/1470581/files/CERN-ATS-2012-222.pdf 801102 1614476 http://cds.cern.ch/record/1470581/files/CLIC_note_978.pdf 656785 1815945 http://cds.cern.ch/record/1470581/files/CERN-ATS-2012-222.pdf?subformat=pdfa pdfa 801102 1858441 http://cds.cern.ch/record/1470581/files/CLIC_note_978.pdf?subformat=pdfa pdfa 801102 22473 http://cds.cern.ch/record/1470581/files/CLIC_note_978.gif?subformat=icon-700 icon-700 801102 5363 http://cds.cern.ch/record/1470581/files/CLIC_note_978.gif?subformat=icon icon Beam impedance study of the stripline kicker for the CLIC damping ring oai:cds.cern.ch:1470581 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Geneva CERN 01 Aug 2012 eng CERN Library CLIC-Note-0978 13 1445554 1849 neworleans20120520 PUBLIC 1470580 20241025033900.0 ARTICLE ConferencePaper Faus-Golfe, A Valencia U., IFIC Barnes, M J CERN Toral, F CIEMAT, Madrid Belver-Aguilar, C Valencia U., IFIC CERN-ATS-2012-221 CLIC Not applicable CERN ARTICLE 000725118CER shauna.dillon@cern.ch The CLIC design relies on the presence of Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve, through synchrotron radiation, the very low emittance needed to fulfill the luminosity requirements. Kicker systems are required to inject and extract the beam from the Pre-Damping and Damping Rings. In order to achieve both low beam coupling impedance and reasonable broadband impedance matching to the electrical circuit, striplines have been chosen for the kicker elements. In this paper the final design for the DR kicker is presented, including an optimization of the geometric parameters to achieve the requirements for both characteristic impedance and field homogeneity. In addition, a sensitivity analysis of characteristic impedance and field homogeneity to geometric parameters is reported. CC-BY publication JACoW CERN EDS CLAS1 CLIC-Note CLICARCHIVE SzGeCERN Accelerators and Storage Rings n 201231 a2012 CLIC-Note-977 4 p ATS TUPPR016 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR016.pdf Published version from JaCoW 656783 1090229 http://cds.cern.ch/record/1470580/files/CERN-ATS-2012-221.pdf 801101 1169025 http://cds.cern.ch/record/1470580/files/CLIC_note_977.pdf 656783 1706941 http://cds.cern.ch/record/1470580/files/CERN-ATS-2012-221.pdf?subformat=pdfa pdfa 801101 1755127 http://cds.cern.ch/record/1470580/files/CLIC_note_977.pdf?subformat=pdfa pdfa 801101 26171 http://cds.cern.ch/record/1470580/files/CLIC_note_977.gif?subformat=icon-700 icon-700 801101 6004 http://cds.cern.ch/record/1470580/files/CLIC_note_977.gif?subformat=icon icon Final cross section design of the stripline kicker for the CLIC damping rings oai:cds.cern.ch:1470580 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Geneva CERN 01 Aug 2012 eng CERN Library CLIC-Note-0977 13 1445554 1843 neworleans20120520 PUBLIC 1470577 20241024143140.0 ARTICLE ConferencePaper Barnes, M J CERN Kovermann, J CERN Calatroni, S CERN Wuensch, W CERN Soares, R H CERN CERN-ATS-2012-220 CLIC Not applicable CERN ARTICLE 000725117CER shauna.dillon@cern.ch Compact Linear Collider (CLIC) RF structures must be capable of sustaining high surface electric fields, in excess of 200 MV/m, with a breakdown (BD) rate below 3×10-7 breakdowns/pulse/m. Achieving such a low rate requires a detailed understanding of all the steps involved in the mechanism of breakdown. One of the fundamental studies is to investigate the statistical characteristics of the BD rate phenomenon at very low values to understand the origin of an observed dependency of the surface electric field raised to the power of 30. To acquire sufficient BD data, in a reasonable period of time, a high repetition rate pulse generator is required for an existing d.c. spark system at CERN. Following BD of the material sample the pulse generator must deliver a current pulse of several 10’s of Amperes for ~2 μs. A high repetition rate pulse generator has been designed, built and tested; this utilizes pulse forming line technology and employs MOSFET switches. This paper describes the design of the pulse generator and presents measurement results. CC-BY publication JACoW CERN EDS CLAS1 CLIC-Note CLICARCHIVE SzGeCERN Accelerators and Storage Rings n 201231 a2012 CLIC-Note-973 4 p ATS THPPC061 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 https://accelconf.web.cern.ch/IPAC2012/papers/THPPC061.pdf Published version from JaCoW 656782 496259 http://cds.cern.ch/record/1470577/files/CERN-ATS-2012-220.pdf 801097 468699 http://cds.cern.ch/record/1470577/files/CLIC_note_973.pdf 656782 1698834 http://cds.cern.ch/record/1470577/files/CERN-ATS-2012-220.pdf?subformat=pdfa pdfa 801097 1763820 http://cds.cern.ch/record/1470577/files/CLIC_note_973.pdf?subformat=pdfa pdfa 801097 27480 http://cds.cern.ch/record/1470577/files/CLIC_note_973.gif?subformat=icon-700 icon-700 801097 6257 http://cds.cern.ch/record/1470577/files/CLIC_note_973.gif?subformat=icon icon A 12 kV, 1 kHz, Pulse Generator for Breakdown Studies of Samples for CLIC RF Accelerating Structures oai:cds.cern.ch:1470577 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Geneva CERN 01 Aug 2012 eng CERN Library CLIC-Note-0973 13 1445554 3431 neworleans20120520 PUBLIC 1470576 20240223164757.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN LHC Not applicable Adraktas, P CERN Baer, T CERN Barnes, M J CERN Cerutti, F CERN Ferrari, A CERN Garrel, N CERN Gerardin, A CERN Guinchard, M CERN Lechner, A CERN Masi, A CERN Mertens, V CERN Morón Ballester, R CERN Redaelli, S CERN Uythoven, J CERN Vlachoudis, V CERN Zimmermann, F CERN AUTHOR|(CDS)2067941 #BEARD# 000725116CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-219 Transient beam losses on a time scale of a few ms have been observed in the LHC injection kickers, occurring mainly shortly after beam injection with a strong correlation in time to the kicker pulsing. The beam losses, which have at times affected LHC availability, are attributed to micron scale ceramic dust particles detached from the alumina beam pipe and accelerated into the beam. The beam related observations are described, together with laboratory measurements of beam pipe contamination and kicker vibration, simulations of electric field in the beam pipe and the basic dynamic model. Energy deposition simulations modelling the beam losses are presented and compared to measurement. Extrapolations to future LHC operation at higher intensities and energies are made, and prospects for mitigation are discussed. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS TUPPR092 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470576/files/CERN-ATS-2012-219.pdf http://cds.cern.ch/record/1470576/files/CERN-ATS-2012-219.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR092.pdf Published version from JaCoW Transient beam losses in the LHC injection kickers from micron scale dust particles oai:cds.cern.ch:1470576 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 eng Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# 1445554 2044 neworleans20120520 PUBLIC 1470573 20240223164757.0 CERN EDS CLAS1 Barnes, M J CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable 000725115CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-218 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. Simulations have been carried out to define component specifications for the inductive adder and this paper reports on the results of tests and measurements of various components. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS THPPD076 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470573/files/CERN-ATS-2012-218.pdf http://cds.cern.ch/record/1470573/files/CERN-ATS-2012-218.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPD076.pdf Published version from JaCoW Evaluation of Components for the High Precision Inductive Adder for the CLIC Damping Rings oai:cds.cern.ch:1470573 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Holma, J CERN eng 1445554 3692 neworleans20120520 PUBLIC 1470571 20240223164757.0 CERN EDS CLAS1 Fowler, T CERN Atanasov, M G CERN EBG MedAustron Kramer, T CERN EBG MedAustron Stadlbauer, T CERN EBG MedAustron Geneva CERN 01 Aug 2012 Not applicable Not applicable 000725113CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-217 Metallized racetrack vacuum chambers will be used in the pulsed magnets of the Austrian cancer therapy and research facility, MedAustron. It is important that the metallization does not unduly degrade field rise and fall times or the flattop of the field pulse in the kicker magnets. This was of particular concern for a tune kicker magnet, which has a specified rise and fall time of 100 ns. The impact of the metallization, upon the transient field response, has been studied using Finite Element Method (FEM) simulations: the dependency of the field response to the metallization thickness and resistivity are presented in this paper and formulae for the field response, for a ramped transient excitation current, are given. An equivalent circuit for the metallization allows the effect of an arbitrary excitation to be studied, with a circuit simulator, and the circuit optimized. Furthermore, results of simulations of the effect of a magnetic brazing collar, located between the ceramic vacuum chamber and flange, of the tune kicker magnet, are reported. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS THPPD074 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470571/files/CERN-ATS-2012-217.pdf https://accelconf.web.cern.ch/IPAC2012/papers/THPPD074.pdf Published version from JaCoW Effect of a metallized chamber upon the field response of a kicker magnet: simulations results and analytical calculations oai:cds.cern.ch:1470571 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Barnes, M J CERN eng 1445554 3686 neworleans20120520 PUBLIC 1470570 20240223164757.0 CERN EDS CLAS1 Barnes, M J CERN Mueller, F CERN Kramer, T EBG MedAustron CERN Stadlbauer, T EBG MedAustron CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable 000725112CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-216 MedAustron, a centre for ion-therapy and research, will comprise an accelerator facility based on a synchrotron for the delivery of protons and light ions for cancer treatment. The Low Energy Beam Transfer line (LEBT) to the synchrotron contains an electrostatic fast deflector (EFE) which, when energized, deviates the continuous beam arriving from the ion source onto a Faraday Cup: the specified voltage is ±3.5 kV. De-energizing the EFE for variable pulse durations from 500 ns up to d.c. allows beam passage for multi-turn injection into the synchrotron. To maintain beam quality in the synchrotron, the EFE pulse generator requires rise and fall times of less than 300 ns between 90 % of peak voltage and a ±1 V level. To achieve this, a pulsed power supply (PKF), with high voltage MOSFET switches connected in a push-pull configuration, will be mounted in close proximity to the deflector itself. A fast, large dynamic range monitoring circuit will verify switching to the ±1 V level and subsequent flat bottom pulse quality. A prototype will be installed in the injector test stand in 2012; this paper presents the design and first measurements of the PKF and its monitoring circuit. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS THPPD075 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470570/files/CERN-ATS-2012-216.pdf http://cds.cern.ch/record/1470570/files/CERN-ATS-2012-216.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPD075.pdf Published version from JaCoW Design and measurements of a fast high-voltage pulse generator for the MedAustron Low Energy Transfer line fast deflector oai:cds.cern.ch:1470570 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Fowler, T CERN eng 1445554 3689 neworleans20120520 PUBLIC 1470569 20240223164757.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN LHC Not applicable Boccardi, A CERN Bracco, C CERN Bravin, E CERN Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# Höfle, W CERN Jacquet, D CERN Jeff, A CERN Kain, V CERN Meddahi, M CERN AUTHOR|(CDS)2051014 #BEARD# Roncarolo, F CERN Uythoven, J CERN Valuch, D CERN Gianfelice-Wendt, E Fermilab 000725111CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-215 The presence of significant intensities of un-bunched beam is a potentially serious issue in the LHC. Procedures using damper kickers for cleaning both the Abort Gap (AG) and the buckets targeted for injection, are currently in operation at flat bottom. Recent observations of relatively high population of the AG during physics runs brought up the need for AG cleaning during luminosity operation. In this paper the results of experimental studies performed in October 2011 are presented. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS MOPPD058 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470569/files/CERN-ATS-2012-215.pdf http://cds.cern.ch/record/1470569/files/CERN-ATS-2012-215.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/MOPPD058.pdf Published version from JaCoW LHC abort gap cleaning studies during luminosity operation oai:cds.cern.ch:1470569 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Bartmann, W CERN eng 1445554 496 neworleans20120520 PUBLIC 1470565 20240223164756.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN PS Booster Borburgh, J CERN Gilardoni, S CERN Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# Newborough, A CERN Pittet, S CERN Steerenberg, R CERN Yu, C Beijing, Inst. High Energy Phys. 000725110CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-214 Within the framework of the CERN PS Booster (PSB) energy upgrade from 1.4 to 2 GeV, the PSB-to-PS transfer line will be adapted for pulse-to-pulse modulated operation. A modified lattice is presented including a redesign of the switching dipole between ISOLDE and PS together with a changed focussing structure. Optics solutions optimized for small emittance LHC beams as well as for the large emittance high-intensity (HI) beams are shown. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS MOPPD057 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470565/files/CERN-ATS-2012-214.pdf http://cds.cern.ch/record/1470565/files/CERN-ATS-2012-214.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/MOPPD057.pdf Published version from JaCoW CERN PSB to PS Transfer Modifications for the 2 GeV Upgrade oai:cds.cern.ch:1470565 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Bartmann, W CERN eng 1445554 493 neworleans20120520 PUBLIC 1470564 20240223164756.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN LHC Not applicable Antonakakis, T CERN Balhan, B CERN Borburgh, J CERN Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# Maglioni, C CERN Versaci, R CERN 000725109CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-213 The Beam Dumping System for the Large Hadron Collider comprises for each ring a set of horizontally deflecting extraction kicker magnets, vertically deflecting steel septa, dilution kickers and finally, a couple of hundred meters further downstream, an absorber block. A mobile diluter (TCDQ) protects the superconducting quadrupole immediately downstream of the extraction as well as the arc at injection energy and the triplet aperture at top energy from bunches with small impact parameters, in case of a beam dump that is not synchronized with the particle free gap or a spontaneous firing of the extraction kickers. Simulations have shown that an asynchronous dump of a 7 TeV nominal beam into the TCDQ absorber blocks could damage it. This paper describes the proposed changes to this device in order to maintain the protection for the downstream elements while reducing the risk of damaging the TCDQ in case of such a beam loss. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS MOPPD081 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470564/files/CERN-ATS-2012-213.pdf http://cds.cern.ch/record/1470564/files/CERN-ATS-2012-213.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/MOPPD081.pdf Published version from JaCoW Upgrade of the LHC Beam Dumping Protection Elements oai:cds.cern.ch:1470564 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Weterings, W CERN eng 1445554 556 neworleans20120520 PUBLIC 1470562 20240223164756.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN PS Booster Balhan, B CERN Benedetto, E CERN Borburgh, J CERN Bracco, C CERN Carli, C CERN Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# Hanke, K CERN Mikulec, B CERN AUTHOR|(CDS)2068050 #BEARD# Newborough, A CERN Noulibos, R CERN Tan, J CERN 000725108CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-212 The 160 MeV H- beam from the LINAC4 will be injected into the 4 superimposed rings of the PS Booster (PSB) with a new H- charge-exchange injection system. This entails a massive upgrade of the injection region. The hardware requirements and constraints, the performance specifications and the design of the H- injection region are described. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS TUPPR091 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470562/files/CERN-ATS-2012-212.pdf http://cds.cern.ch/record/1470562/files/CERN-ATS-2012-212.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR091.pdf Published version from JaCoW Status of the 160 MeV H- Injection into the CERN PSB oai:cds.cern.ch:1470562 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Weterings, W CERN eng 1445554 2041 neworleans20120520 PUBLIC 1470559 20240223164756.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN LHC Not applicable Ducimetière, L CERN Garrel, N CERN Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# Mertens, V CERN Weterings, W CERN 000725107CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-211 The two LHC injection kicker magnet (MKI) systems must produce a kick of 1.3 T.m with a flat top duration variable up to 7860 ns, and rise and fall times of less than 900 ns and 3000 ns, respectively. A beam screen is placed in the aperture of the magnets: the screen consists of a ceramic tube with conductors on the inner wall. The conductors provide a path for the image current of the high intensity LHC beam and screen the ferrite against wake fields. The conductors initially used gave adequately low beam coupling impedance however screen conductor discharges occurred during pulsing of the magnet; hence an alternative design with fewer screen conductors was implemented to meet the often conflicting requirements for low beam coupling impedance, fast magnetic field rise-time and good high voltage behaviour. During 2011 the LHC was operated with high intensity beam, coasting for many hours at a time, resulting in heating of the ferrite yoke of the MKIs. This paper presents an analysis of thermal measurement data and an extrapolation of the heating for future operation; in addition means are discussed for reducing ferrite heating and improving cooling. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS TUPPR090 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470559/files/CERN-ATS-2012-211.pdf http://cds.cern.ch/record/1470559/files/CERN-ATS-2012-211.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR090.pdf Published version from JaCoW Analysis of ferrite heating of the LHC injection kickers and proposals for future reduction of temperature oai:cds.cern.ch:1470559 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Barnes, M J CERN eng 1445554 2038 neworleans20120520 PUBLIC 1470558 20240223164755.0 CERN EDS CLAS1 Geneva CERN 01 Aug 2012 CERN LHC Not applicable Bartmann, W CERN Goddard, B CERN AUTHOR|(CDS)2108505 #BEARD# Kain, V CERN Uythoven, J CERN 000725106CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-210 Machine safety depends critically on the correct setup of the protection elements. One of the injection protection elements consists of exceptionally long jaws (4 m). An angular offset of the jaws could affect significantly the measured beam size and, as a consequence, the correct setup with respect to the beam. Dedicated studies and cross-calibrations have been performed to quantify the effect of tilts and offsets on the setup of this stopper and to check the provided passive protection. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS TUPPR096 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470558/files/CERN-ATS-2012-210.pdf http://cds.cern.ch/record/1470558/files/CERN-ATS-2012-210.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR096.pdf Published version from JaCoW Angular alignment of LHC injection protection stopper oai:cds.cern.ch:1470558 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Bracco, C CERN eng 1445554 2056 neworleans20120520 PUBLIC 1470556 20240223164755.0 CERN EDS CLAS1 Fuchsberger, K CERN Schmidt, R CERN Wenninger, J CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable 000725104CER ARTICLE ConferencePaper shauna.dillon@cern.ch n 201231 a2012 CERN-ATS-2012-208 The Large Hadron Collider (LHC) has an unprecedented nominal stored beam energy of up to 362 MJ per beam. In order to ensure an adequate machine protection by the collimation system, a high reproducibility of the beam position at collimators and special elements like the final focus quadrupoles is essential. This is realized by a combination of manual orbit corrections, feed forward and real time feedback. In order to protect the LHC against inconsistent orbit corrections, which could put the machine in a vulnerable state, a novel software-based interlock system for orbit corrector currents was developed. In this paper, the principle of the new interlock system is described and the reproducibility of the LHC orbit correction is discussed against the background of this system. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings CERN ARTICLE 13 4 p ATS THPPP010 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470556/files/CERN-ATS-2012-208.pdf http://cds.cern.ch/record/1470556/files/CERN-ATS-2012-208.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPP010.pdf Published version from JaCoW LHC Orbit Correction Reproducibility and Related Machine Protection oai:cds.cern.ch:1470556 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Baer, T CERN eng 1445554 3746 neworleans20120520 PUBLIC 1470341 20240223164754.0 CERN EDS CLAS1 ARTICLE ConferencePaper Dahlerup-Petersen, K CERN Denz, R CERN Siemko, A CERN Steckert, J CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable CERN ARTICLE 000725051CER shauna.dillon@cern.ch n 201230 a2012 CERN-ATS-2012-204 The interconnections between the LHC main magnets are made of soldered joints (splices) of two superconducting cables stabilized by a copper bus-bar. After the 2008 LHC incident, caused by a defective interconnection, a new layer of high resolution magnet circuit quench protection (nQPS) has been developed and integrated with the existing systems. It allowed mapping of the resistances of all superconducting splices during the 2009 commissioning campaign. Since April 2010, when the LHC was successfully restarted at 3.5 TeV, every bus bar interconnection is constantly monitored by the nQPS electronics. The acquired data are saved to the LHC Logging Database. The paper will briefly describe the data analysis method and will present the results from the two years of resistance measurements. Although no splice was found with resistance higher than 3.3 n􀀀 and no significant degradation in time was observed so far, the monitoring of splices will stay active till the end of LHC 4 TeV run. The detected outliers will be repaired during the Splice Consolidation Campaign in 2013-2014. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings 4 p ATS THPPD026 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470341/files/CERN-ATS-2012-204.pdf http://cds.cern.ch/record/1470341/files/CERN-ATS-2012-204.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPD026.pdf Published version from JaCoW Splice Resistance Measurements in the LHC Main Superconducting Magnet Circuits by the New Quench Protection System oai:cds.cern.ch:1470341 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Charifoulline, Z CERN eng 13 1445554 3557 neworleans20120520 PUBLIC 1470336 20241025034319.0 ARTICLE ConferencePaper Ferracin, P CERN Fessia, P CERN Karppinen, M CERN Mazet, J CERN Russenschuck, S CERN Peiffer, P Karlsruhe, Inst. Technol. Grau, A Karlsruhe, Inst. Technol. CERN-ATS-2012-202 CLIC Not applicable CERN ARTICLE 000725048CER shauna.dillon@cern.ch SzGeCERN Accelerators and Storage Rings n 201230 a2012 CLIC-Note-979 Geneva CERN 01 Aug 2012 4 p 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, Nb$_{3}$Sn 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, Nb$_{3}$Sn wiggler magnets are under investigation at CERN despite the challenging manufacturing process. This paper presents first results of Nb$_{3}$Sn coils and short model tests and outlines the further plans for developing Nb$_{3}$Sn wiggler magnets at CERN. CC-BY publication JACoW CERN EDS CLAS1 CLIC-Note CLICARCHIVE ATS TUPPR061 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR061.pdf Published version from JaCoW 651883 1454089 http://cds.cern.ch/record/1470336/files/CERN-ATS-2012-202.pdf 801103 1534663 http://cds.cern.ch/record/1470336/files/CLIC_note_979.pdf 651883 2887532 http://cds.cern.ch/record/1470336/files/CERN-ATS-2012-202.pdf?subformat=pdfa pdfa 801103 28862 http://cds.cern.ch/record/1470336/files/CLIC_note_979.gif?subformat=icon-700 icon-700 801103 2923754 http://cds.cern.ch/record/1470336/files/CLIC_note_979.pdf?subformat=pdfa pdfa 801103 6665 http://cds.cern.ch/record/1470336/files/CLIC_note_979.gif?subformat=icon icon First magnetic test of a superconducting Nb$_{3}$Sn Wiggler magnet for CLIC oai:cds.cern.ch:1470336 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Schoerling, D CERN eng CERN Library CLIC-Note-0979 13 1445554 1957 neworleans20120520 PUBLIC 1470335 20240223164746.0 CERN EDS CLAS1 ARTICLE ConferencePaper Modena, M CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable CERN ARTICLE 000725047CER shauna.dillon@cern.ch n 201230 a2012 CERN-ATS-2012-201 A critical aspect of the Compact Linear Collider (CLIC) design is represented by the Accelerator/Experiment interface (called Machine Detector Interface or MDI). In the 3 TeV CLIC layout, the final focus QD0 quadrupole will be located inside the end-cap of the detector itself. This complex MDI scenario required to be simulated with a full 3D-FE analysis. This study was critical to check and control the magnetic cross-talk between the detector solenoid and the final focus magnet and therefore to optimize the design of an “antisolenoids” system needed to shield the QD0 and the e-/e+ beams from the detector magnetic field. In this paper the development and evolution of the computational FE model is presented together with the results obtained and their implication on the CLIC MDI design. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings 4 p ATS TUPPR052 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470335/files/CERN-ATS-2012-201.pdf https://accelconf.web.cern.ch/IPAC2012/papers/TUPPR052.pdf Published version from JaCoW 3D FEA Computation of the CLIC Machine Detector Interface Magnets oai:cds.cern.ch:1470335 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Bartalesi, A CERN eng 13 1445554 1936 neworleans20120520 PUBLIC 1470334 20240223164745.0 CERN EDS CLAS1 ARTICLE ConferencePaper Dunkel, O CERN Garcia Perez, J CERN Petrone, C CERN Solodko, E CERN Thonet, P CERN Tommasini, D CERN Vorozhtsov, A CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable CERN ARTICLE 000725046CER shauna.dillon@cern.ch n 201230 a2012 CERN-ATS-2012-200 In the framework of the Compact Linear Collider (CLIC) R&D, a tunable hybrid magnet design has been proposed for the final focus QD0 quadrupole. A short model of the magnet has been realized in order to validate the novel design and its expected performances. In order to achieve extremely high quadrupole gradients (>500 T/m), the magnet design combines: a core structure made in magnetic CoFe alloy “Permendur”, permanent magnet blocks, and air-cooled electromagnetic coils. Relevant aspects of this design are the wide tunability of the gradient range, the compactness and the absence of any vibrations. In this paper a reminder of the magnet design concept is given; then, the procurement and assembly main aspects are presented, followed by the results of the magnetic measurements. Finally, some manufacturing considerations relative to a full size magnet procurement are discussed. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings 4 p ATS THPPD010 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470334/files/CERN-ATS-2012-200.pdf https://accelconf.web.cern.ch/IPAC2012/papers/thppd010.pdf Published version from JaCoW http://cds.cern.ch/record/1470334/files/CERN-ATS-2012-200.pdf?subformat=pdfa pdfa Design, Assembly and First Measurements of a short Model for CLIC Final Focus Hybrid Quadrupole QD0 oai:cds.cern.ch:1470334 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Modena, M CERN eng 13 1445554 3515 neworleans20120520 PUBLIC 1470332 20240223164745.0 CERN EDS CLAS1 ARTICLE ConferencePaper Atieh, S CERN Duarte Ramos, D CERN Pirotte, O CERN Principe, R CERN Savary, F CERN Scheuerlein, C CERN Tock, J Ph CERN Verweij, A CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable CERN ARTICLE 000725045CER shauna.dillon@cern.ch n 201230 a2012 CERN-ATS-2012-199 In 2008 a defective connection in one of the 13 kA dipole circuits of the LHC caused an electric breakdown that resulted in extensive damage in a sector of the accelerator. The investigation performed after the accident showed the necessity to consolidate the electrical splices of the 13 kA dipole and quadrupole circuits in order to operate the LHC at its nominal energy of 7 TeV. These circuits are powered through electrical feedboxes located at each end of the 8 sectors of the LHC. In the feedboxes the current is routed from room temperature to the superconducting magnets busbars along current leads and superconducting busbars and flows through at least two internal splices. These splices are based on the same technology as the magnet-to-magnet ones but they are significantly different in terms of environment and configuration. As for the magnet to magnet splices, a consolidation will be necessary to operate them at nominal current. This paper presents an analysis of the properties of these splices and the technologies that will be used to consolidate them. The quality control and the workflow to perform this operation during the first long shutdown of the LHC are also presented. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings 4 p ATS THPPD027 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470332/files/CERN-ATS-2012-199.pdf http://cds.cern.ch/record/1470332/files/CERN-ATS-2012-199.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPD027.pdf Published version from JaCoW Consolidation of the 13 kA Splices in the Electrical Feedboxes of the LHC oai:cds.cern.ch:1470332 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Perin, A CERN eng 13 1445554 3560 neworleans20120520 PUBLIC 1470331 20240223164745.0 CERN EDS CLAS1 ARTICLE ConferencePaper Bajko, M CERN Deferne, G CERN Dunkel, O CERN Fiscarelli, L CERN Russenschuck, S CERN Giloteaux, D CERN Walckiers, L CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable CERN ARTICLE 000725044CER shauna.dillon@cern.ch n 201230 a2012 CERN-ATS-2012-198 SzGeCERN Accelerators and Storage Rings 4 p A new measurement system, based on a large-diameter search-coil rotating in the superfluid helium, a fast digital integrator, a motor drive unit with slip rings, and a flexible software environment was developed at CERN for the measurement of dynamic effects in superconducting magnets. This system has made it possible the measure, with a resolution of up to 1 Hz, the multipole field errors due to superconductor magnetization and interstrand coupling currents. In this paper we present the development and calibration of the measurement system, its installation in the vertical cryostat of CERN’s recently refurbished test station, and its application to the US-LARP built, 120-mm aperture Nb$_{3}$Sn quadrupole magnet (HQ01e) for the upgrade of the LHC insertion regions. CC-BY publication JACoW ATS THPPD030 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470331/files/CERN-ATS-2012-198.pdf http://cds.cern.ch/record/1470331/files/CERN-ATS-2012-198.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPD030.pdf Published version from JaCoW Characterization of a Measurement System for Dynamic Effects in Large-Aperture SC Quadrupole Magnets oai:cds.cern.ch:1470331 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Buzio, M CERN eng 13 1445554 3569 neworleans20120520 PUBLIC 1470329 20240223164745.0 CERN EDS CLAS1 ARTICLE ConferencePaper Bertinelli, F CERN Bordry, F CERN Fessia, P CERN Ostojic, R CERN Perin, A CERN Prin, H CERN Savary, F CERN Scheuerlein, C CERN Ten Kate, H H J CERN Verweij, A CERN Willering, G P CERN Geneva CERN 01 Aug 2012 CERN LHC Not applicable CERN ARTICLE 000725043CER shauna.dillon@cern.ch n 201230 a2012 CERN-ATS-2012-197 Following the incident in one of the main dipole circuits of the Large Hadron Collider (LHC) in September 2008, a detailed analysis of all magnet circuits has been performed by a dedicated task force. This analysis has revealed critical issues in the design of the 13 kA splices between the superconducting dipole and quadrupole magnets. These splices have to be consolidated before increasing the beam energy above 4 TeV and operating the LHC at 6.5-7 TeV per beam. The design of the consolidated 13 kA splices is complete and has been reviewed by an international committee of experts. Also, all other types of superconducting circuits have been thoroughly screened for potential safety issues and several important recommendations were established. They were critically assessed and the resulting actions are presented. In addition to the work on the 13 kA splices, other interventions will be performed during the first long shut-down of the LHC to consolidate globally all superconducting circuits. The associated quality control has been defined. Schedule constraints, repair production rate, available space and resources are presented as well. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings 4 p ATS THPPD032 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470329/files/CERN-ATS-2012-197.pdf http://cds.cern.ch/record/1470329/files/CERN-ATS-2012-197.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/THPPD032.pdf Published version from JaCoW Consolidation of the LHC Superconducting Circuits: A Major Step towards 14 TeV Collisions oai:cds.cern.ch:1470329 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Tock, J Ph CERN eng 13 1445554 3575 neworleans20120520 PUBLIC 1470324 20240223164745.0 CERN EDS CLAS1 ARTICLE ConferencePaper 1558597 Aquilina, N CERN Fiscarelli, L CERN Garcia Tomás, R CERN Giovannozzi, M CERN Hagen, P CERN Lamont, M CERN Maclean, E CERN Redaelli, S CERN Schmidt, F CERN Strzelczyk, M CERN Walckiers, L CERN Wenninger, J CERN Sammut, N Malta U. CERN-ATS-2012-195 CERN LHC Not applicable CERN ARTICLE 000725041CER shauna.dillon@cern.ch The magnetic model of the LHC is based on a fit of the magnetic measurements through equations that model the field components (geometric, saturation, persistent) at different currents. In this paper we will review the main results related to the magnetic model during the run of the LHC in 2010-2011: with a top energy of 3.5 TeV, all components of the model but the saturation are visible. We first review the main results relative to the decay at injection plateau, dependence on powering history, and snapback at the beginning of the ramp for both tune and chromaticity. We discuss the precision obtained in tracking the magnets during the ramp, where the persistent current components gradually disappear. We conclude by presenting the behaviour of the quadrupoles model during the squeeze. CC-BY publication JACoW SzGeCERN Accelerators and Storage Rings n 201230 a2012 Geneva CERN 01 Aug 2012 4 p ATS WEEPPB014 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470324/files/CERN-ATS-2012-195.pdf http://cds.cern.ch/record/1470324/files/CERN-ATS-2012-195.pdf?subformat=pdfa pdfa https://accelconf.web.cern.ch/IPAC2012/papers/WEEPPB014.pdf Published version from JaCoW The Magnetic Field Model of the Large Hadron Collider: Overview of Operation at 3.5 and 4 TeV oai:cds.cern.ch:1470324 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 eng Todesco, E CERN AUTHOR|(CDS)2108516 #BEARD# 13 1445554 2194-2196 neworleans20120520 PUBLIC 1470321 20240223164744.0 CERN EDS CLAS1 SzGeCERN Accelerators and Storage Rings ARTICLE ConferencePaper Bottura, L CERN de Rijk, G CERN Rossi, L CERN Geneva CERN 01 Aug 2012 Not applicable Not applicable CERN ARTICLE 000725036CER shauna.dillon@cern.ch CERN-ATS-2012-194 The exploitation and evolution of the CERN accelerator complex pose a continuous challenge for magnet engineers. Superconducting and resistive magnets have a comparable share. The overall mass of either is approximately 50,000 tons, spread over 3 major machines (PS, SPS and LHC), two large experimental area, and a number of smaller experiments and accelerator rings. On the short term (2012-2014) the CERN plan is to upgrade its injection chain (Linac4) and experimental area (HIEIsolde, ELENA) that require mostly a multitude of resistive magnets. The medium-term plan for the evolution of the LHC complex (2015-2021), also referred to as High-Luminosity LHC, foresees interventions on about 1 km of the machine, with magnets to be substituted with higher field, larger aperture, or both. On the long term (2025-2035) we are exploring the technological challenges of very high field magnets, at the verge of 20 T for a High Energy LHC (HE-LHC), which would also call for fast cycled SC magnets in a revamped injector, and we are studying extremely stable high gradient quadrupoles for the Compact Linear Collider (CLIC). CC-BY publication JACoW n 201230 a2012 3 p ATS THPPD009 Conf. Proc. C1205201 2012 IPAC2012 C12-05-20.1 http://cds.cern.ch/record/1470321/files/CERN-ATS-2012-194.pdf https://accelconf.web.cern.ch/IPAC2012/papers/thppd009.pdf Published version from JaCoW Accelerators Magnet R&D Programme at CERN oai:cds.cern.ch:1470321 cerncds:FULLTEXT cerncds:CERN:FULLTEXT cerncds:CERN 2012 Tommasini, D CERN eng 13 1445554 3512-3514 neworleans20120520 PUBLIC