Braun, H, Corsini, R, Delahaye, J P, De Roeck, A, Döbert, S, Ferrari, A, ...
This note presents the CLIC parameter set as of beginning 2008 and describes the different subsystems,pointing out how the design of the different components is driven. This design emerged from an...
Optics Design Considerations for the CLIC Pre-Damping Rings (2008)
The CLIC pre-damping rings have to accommodate a large emittance beam, coming in particular from the positron source and reduce its size to low enough values for injection into the main damping...
Parameter Scan for the CLIC Damping Rings (2008)
Papaphilippou, Y, Braun, H H, Korostelev, M
Triggered by the RF frequency reduction of the CLIC main linac cavities, the damping ring parameters had to be reevaluated and the rings performance adapted to the new luminosity requirements. In...
Electron Cloud Build Up and Instability in the CLIC Damping Rings (2008)
Rumolo, G, Bruns, W, Papaphilippou, Y
Electron cloud can be formed in the CLIC positron damping ring and cause intolerable tune shift and beam instability. Build up simulations with the Faktor2 code, developed at CERN, have been done to...
Collective Effects in the CLIC Damping Rings (2008)
Rumolo, G, Jeanneret, J B, Papaphilippou, Y, Quatraro, D
Possible performance limitations coming fromcollective effects in the CLIC damping rings are the subject of this paper. In particular, the consequences of space charge, due to the very high beam...
Beam Losses and Collimation Considerations for PS2 (2008)
Barranco, J, Bartmann, W, Benedikt, M, Papaphilippou, Y
The high intensity beams with different emittances foreseen to be delivered by the PS2, an upgraded version of the actual CERN Proton Synchrotron, require strict control of beam losses in order to...
Completion of the Series Fabrication of the Main Superconducting Quadrupole Magnets of LHC (2008)
Tortschanoff, Theodor, Modena, M, Papaphilippou, Y, Rossi, L, Schirm, K M, Burgmer, R, ...
By end of November 2006, the last main superconducting quadrupole cold mass needed for the installation was delivered by ACCEL Instruments to CERN. In total, 360 cold masses for the arc regions of...
Magnet Acceptance and Allocation at the LHC Magnet Evaluation Board (2008)
Bestmann, P, Bottura, L, Catalan-Lasheras, N, Fartoukh, S, Gilardoni, S, Giovannozzi, M, ...
The normal and superconducting magnets for the LHC ring have been carefully examined to insure that each of about 1900 assemblies is suitable for the operation in the accelerator. Hardware experts...
Superconductive Damping Wigglers for the CLIC Project (2007)
Baumbach, T, Bernard, A, Braun, H, Casalbuoni, S, Grau, A, Hagelstein, M, ...
The CLIC damping ring requires wigglers with both high on-axis fields and short periods. The present design foresees a superconductive wiggler with a period length of 5 cm, a peak on-axis field of...
Space-Charge Compensation Options for the LHC Injector Complex (2007)
Aiba, M, Chanel, M, Dorda, U, Franchetti, G, Garoby, R, Koutchouk, Jean-Pierre, ...
Space-charge effects have been identified as the most serious intensity limitation in the CERN PS and PS Booster, on the way towards ultimate LHC performance and beyond. We here explore the...
Beam Loss Map Simulations and Measurements in the CERN PS. (2007)
Barranco, J, Berrig, O, Gilardoni, S, Jeanneret, B, Robert-Démolaize, G, Papaphilippou, Y
Numerical tools providing detailed beam loss maps, recently developed for the design of the Large Hadron Collider (LHC) collimation system, were adapted to low energy synchrotrons. Using a MADX...
Alternative running scenarios for the LHCb experiment (2007)
Herr, Werner, Papaphilippou, Y
In this report we study the possibility to collide the beams in LHCb (interaction point 8) with a modified crossing scheme which allows a transparent change of the LHCb spectrometer polarity. In the...
Superconductive damping wigglers for the CLIC project (2007)
Rossmanith, R, Baumbach, T, Bernhard, A, Braun, H-H, Casalbuoni, Sa, Grau, AW, ...
Sorting strategies for the arc quadrupoles of the LHC (2006)
The variation in the field gradient of the LHC arc quadrupoles can not be corrected by the dedicated trim quadrupole circuits. This may result to a beta function beating larger than the one accepted...
Procedures and accuracy estimates for beta-beat correction in the LHC (2006)
Tomás, R, Brüning, O S, Calaga, R, Fartoukh, Stéphane David, Franchi, A, Giovannozzi, Massimo, ...
The LHC aperture imposes a tight tolerance of 20% on the maximum acceptable beta-beat in the machine. An accurate knowledge of the transfer functions for the individually powered insertion...
Accelerator Physics Code Web Repository (2006)
Zimmermann, Frank, Basset, R, Bellodi, G, Benedetto, E, Dorda, U, Giovannozzi, Massimo, ...
In the framework of the CARE HHH European Network, we have developed a web-based dynamic acceleratorphysics code repository. We describe the design, structure and contents of this repository,...
Fartoukh, Stéphane David, Gilardoni, S S, Giovannozzi, Massimo, Jeanneret, J B, Lombardi, A, Papaphilippou, Y, ...
It is customary to evaluate the performance of a circular particle accelerator by computing the dynamical aperture, i.e. the domain in phase space where bounded singleparticle motion occurs. In the...
Transverse "Monopole" Instability Driven by Electron Cloud? (2003)
Benedetto, Elena, Schulte, Daniel, Zimmermann, Frank, Ohmi, K, Papaphilippou, Y, Rumolo, Giovanni
We simulate the long-term emittance growth of a proton beam due to an electron cloud of moderate density. This emittance growth is sometimes characterized by a rapid blow up of the bunch tail, and it...
Beam-Beam Interaction, Electron Cloud and Intrabeam Scattering for Proton Super-bunches (2003)
Ruggiero, F, Zimmermann, Frank, Rumolo, Giovanni, Papaphilippou, Y
Super-bunches are long bunches with a flat longitudinal profile, which could potentially increase the LHC luminosity in a future upgrade. We present example parameters and discuss a variety of issues...
Ruggiero, F, Rumolo, Giovanni, Zimmermann, Frank, Papaphilippou, Y
Possible upgrade scenarios for the Large Hadron Collider (LHC) comprise the operation with either uniform (hollow) bunches or long super-bunches. We discuss the respective merits of these approaches...
Estimates of Diffusion due to Long-range Beam-beam Collisions (2002)
Papaphilippou, Y, Zimmermann, Frank
Weak-strong tracking simulations for the Large Hadron Collider (LHC) have shown that long-range beam-beam collisions give rise to a well-defined diffusive aperture beyond which particles are lost...
Correction Schemes for the Normal Octupole and Decapole Errors in the LHC Dipoles (2000)
Different correction schemes for curing the effect of the normal octupole and decapole multipole errors of the LHC main dipoles, at injection, are investigated. Frequency and diffusion maps are...
Diffusive Aperture Due to Long-Range Beam-Beam Interaction (2000)
Papaphilippou, Y, Zimmermann, Frank
Weak-strong tracking simulations for the Large Hadron Collider (LHC) show that long-range beam-beam collisions give rise to a well-defined diffusive aperture beyond which particles are lost quickly....
Measurements of coherent tune shifts and head-tail growth rates at the CERN SPS (2000)
Zorzano-Mier, M P, Arduini, Gianluigi, Burkhardt, H, Cornelis, Karel, Zimmermann, Frank, Papaphilippou, Y
As part of an ongoing effort to monitor SPS impedance changes with regard to LHC, the coherent tune shifts and head-tail growth rates in the SPS were measured for single proton bunches at 26 GeV....
Frequency maps of LHC models (2000)
The frequency map analysis method is applied in models of LHC optics versions 5 and 6 in order to study their non-linear dynamics. The maps present a global picture of the resonance structure of the...
Measurement of Resonance Driving Terms from Turn-by-Turn Data (1999)
Bartolini, R, Leunissen, L H A, Papaphilippou, Y, Schmidt, F, Verdier, A
It has been shown that the Fourier analysis of recorded turn-by-turn tracking data can be used to derive resonance terms of an accelerator. Besides the resonance driving terms, the non-linear...
Measurement of Resonance Driving Terms from Turn-by-Turn Data (1999)
Bartolini, R, Leunissen, L H A, Papaphilippou, Y, Schmidt, F, Verdier, A
It has been shown that the Fourier analysis of recorded turn-by-turn tracking data can be used to derive resonance terms of an accelerator. Besides the resonance driving terms, the non-linear...
Effects of sextupole time dependence on the LHC dynamic aperture (1999)
Papaphilippou, Y, Schmidt, F, Zimmermann, Frank
A primary concern regarding the LHC dynamic aperture is the time dependence of persistent-current sextupole fields in the superconducting magnets. Decaying slowly during injection, these fields are...
Effects of sextupole time dependence on the LHC dynamic aperture (1999)
Papaphilippou, Y, Schmidt, F, Zimmermann, Frank
A primary concern regarding the LHC dynamic aperture is the time dependence of persistent-current sextupole fields in the superconducting magnets. Decaying slowly during injection, these fields are...
Normal Form Approaches and Resonance Analysis of LHC Models (1998)
In order to understand the dynamic aperture limitations in LHC optics versions 4 and 5 at injection energy (450 GeV), a thorough resonance analysis is performed through Lie perturbation methods and...
Improvement of LHC dynamic aperture via octupole spool pieces for the nominal tunes (1998)
Jin, L, Papaphilippou, Y, Schmidt, F
The dynamic aperture of the LHC optics version 5 at injection energy has been calculated for an opti-mistic error table, the so called target error table, in which erect and/or skew octupolar...
Study of the Non-linear Behaviour of the LHC using Normal Forms (1998)
Normal form tools are used in view of understanding the causes of dynamic aperture limitations in the LHC optics versions 4 and 5. To this end, maps up to 11th order have been produced and analysed...