Author: Cerutti, F.
Paper Title Page
MOOCB01 Beam-induced Quench Tests of LHC Magnets 52
 
  • M. Sapinski, B. Auchmann, T. Bär, W. Bartmann, M. Bednarek, S. Bozyigit, C. Bracco, R. Bruce, F. Cerutti, V. Chetvertkova, K. Dahlerup-Petersen, B. Dehning, E. Effinger, J. Emery, A. Guerrero, E.B. Holzer, W. Höfle, A. Lechner, A. Priebe, S. Redaelli, B. Salvachua, R. Schmidt, N.V. Shetty, A.P. Siemko, E. Skordis, M. Solfaroli Camillocci, J. Steckert, J.A. Uythoven, D. Valuch, A.P. Verweij, J. Wenninger, D. Wollmann, M. Zerlauth, E.N. del Busto
    CERN, Geneva, Switzerland
 
  At the end of the LHC Run1 a 48-hour quench-test campaign took place to investigate the quench levels of superconducting magnets for loss durations from nanoseconds to tens of seconds. The longitudinal losses produced extended from one meter to hundreds of meters and the number of lost protons varied from 108 to 1013. The results of these and other, previously conducted quench experiments, allow the quench levels of several types of LHC magnets under various loss conditions to be assessed. The quench levels are expected to limit LHC performance in the case of steady-state losses in the interaction regions and also in the case of fast losses initiated by dust particles all around the ring. It is therefore required to accurately adjust beam loss abort thresholds in order to maximize the operation time. A detailed discussion of these quench test results and a proposal for additional tests after the LHC restart is presented.  
slides icon Slides MOOCB01 [2.737 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOOCB01  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPRO021 Power Deposition in LHC Magnets With and Without Dispersion Suppressor Collimators Downstream of the Betatron Cleaning Insertion 112
 
  • A. Lechner, B. Auchmann, R. Bruce, F. Cerutti, P.P. Granieri, A. Marsili, S. Redaelli, N.V. Shetty, E. Skordis, G.E. Steele, A.P. Verweij
    CERN, Geneva, Switzerland
 
  The power deposited in dispersion suppressor (DS) magnets downstream of the LHC betatron cleaning insertion is governed by off-momentum protons which predominantly originate from single-diffractive interactions in primary collimators. With higher beam energy and intensities anticipated in future operation, these clustered proton losses could possibly induce magnet quenches during periods of short beam lifetime. In this paper, we present FLUKA simulations for nominal 7 TeV operation, comparing the existing layout with alternative layouts where selected DS dipoles are substituted by pairs of shorter higher-field magnets and a collimator. Power densities predicted for different collimator settings are compared against present estimates of quench limits. Further, the expected reduction factor due to DS collimators is evaluated.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPRO039 Integrated Simulation Tools for Collimation Cleaning in HL-LHC 160
 
  • R. Bruce, C. Bracco, F. Cerutti, A. Ferrari, A. Lechner, A. Marsili, A. Mereghetti, D. Mirarchi, P.G. Ortega, D. Pastor Sinuela, S. Redaelli, A. Rossi, B. Salvachua, V. Vlachoudis
    CERN, Geneva, Switzerland
  • R. Appleby, J. Molson, M. Serluca
    UMAN, Manchester, United Kingdom
  • R.W. Aßmann
    DESY, Hamburg, Germany
  • R.J. Barlow, H. Rafique, A.M. Toader
    University of Huddersfield, Huddersfield, United Kingdom
  • S.M. Gibson, L.J. Nevay
    Royal Holloway, University of London, Surrey, United Kingdom
  • L. Lari
    IFIC, Valencia, Spain
  • C. Tambasco
    University of Rome La Sapienza, Rome, Italy
 
  The Large Hadron Collider is designed to accommodate an unprecedented stored beam energy of 362~MJ in the nominal configuration and about the double in the high-luminosity upgrade HL-LHC that is presently under study. This requires an efficient collimation system to protect the superconducting magnets from quenches. During the design, it is therefore very important to accurately predict the expected beam loss distributions and cleaning efficiency. For this purpose, there are several ongoing efforts in improving the existing simulation tools or developing new ones. This paper gives a brief overview and status of the different available codes.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO039  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPRO041 Multi-turn Tracking of Collision Products at the LHC 166
 
  • A. Marsili, R. Bruce, F. Cerutti, L.S. Esposito, S. Redaelli
    CERN, Geneva, Switzerland
 
  Funding: Research supported by EU FP7 HiLumi LHC - Grant Agreement 284404
The luminosity expected at the interaction points in LHC at 7 TeV will be unprecedented, up to 1034 cm−2 s−1 . Part of the debris produced by the collisions is lost locally im- mediately downstream the Interaction Point (IP), in the matching section and dispersion suppressor. In this paper, the dynamics of collision debris protons is discussed. First, the loss distributions close to the collision points, simulated with two codes – SixTrack and FLUKA – are compared for different layout configurations. Then, SixTrack is used to simulate the fraction of protons that have undergone inelastic interactions with smaller energy and and betatron offsets, which could travel for several turns around the ring and might be lost in other collimation insertions. A preliminary comparison is made between the resulting loss distribution and measurements.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO041  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPRI098 Design Studies of the Upgraded Collimation System in the SPS-to-LHC Transfer Lines 845
 
  • A. Mereghetti, C. Bracco, F. Cerutti, B. Goddard, J. Hrivnak, V. Kain, F.L. Maciariello, M. Meddahi, G.E. Steele
    CERN, Geneva, Switzerland
  • R. Appleby
    UMAN, Manchester, United Kingdom
 
  In the framework of the LHC Injectors Upgrade (LIU) Project, the collimators in the SPS-to-LHC transfer lines are presently under re-design, in order to cope with the unprecedented beam intensities and emittances required by the High Luminosity LHC (HL-LHC). Factors ruling the design phase are the robustness of the jaws on one side and, on the other side, the proton absorption and the emittance blow-up, essential for an effective protection of the equipment in the LHC injection regions and the LHC machine. In view of the new design, based on the one of the currently installed TCDI collimators and past investigations, the FLUKA Monte Carlo code is used to address these two factors. The present studies are intended to give essential feedback to the identification of viable solutions.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI098  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPRO020 Integration of a Neutral Absorber for the LHC Point 8 1052
 
  • A. Santamaría García, R. Alemany-Fernández, H. Burkhardt, F. Cerutti, L.S. Esposito, N.V. Shetty
    CERN, Geneva, Switzerland
 
  The LHCb detector will be upgraded during the second long shutdown (LS2) of the LHC machine, in order to increase its statistical precision significantly. The upgraded LHCb foresees a peak luminosity of L = 1-2 . 1033 cm-2 s−1, with a pileup of 5. This represents ten times more luminosity and five times more pile up than in the present LHC. With these conditions, the pp-collisions and beam losses will produce a non-negligeable beam-induced energy deposition in the interaction region. More precisely, studies have shown that the energy deposition will especially increase on the D2 recombination dipole, which could bring them close to their safety thresholds. To avoid this, the placement of a minimal neutral absorber has been proposed. This absorber will have the same role as the TAN in the high luminosity Interaction Regions (IR) 1 and 5. This study shows the possible dimensions and location of this absorber, and how it would reduce both the peak power density and total heat load.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO020  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPRO027 First Beam Background Simulation Studies at IR1 for High Luminosity LHC 1074
 
  • R. Kwee-Hinzmann, S.M. Gibson
    JAI, Egham, Surrey, United Kingdom
  • G. Bregliozzi, R. Bruce, F. Cerutti, L.S. Esposito, R. Kersevan, A. Lechner, N.V. Shetty
    CERN, Geneva, Switzerland
  • S.M. Gibson
    Royal Holloway, University of London, Surrey, United Kingdom
 
  In the High-Luminosity Large Hadron Collider (HL-LHC) Project, the LHC will be significantly upgraded to attain a peak luminosity of up to 8.5 × 1034 cm-2s-1, thus almost an order of magnitude higher compared to the nominal machine configuration in ATLAS at IP1 and CMS at IP5. In the view of a successful machine setup as well as a successful physics programme, beam induced background studies at IP1 were performed to investigate sources of particle fluxes to the experimental area. In particular as a start of the study, two sources forming the major contributions were simulated in detail: the first one considers inelastic interactions from beam particles hitting tertiary collimators, the second one from beam interactions with residual gas-molecules in the vacuum pipe close by the experiment, referred to as beam-halo and local beam-gas, respectively. We will present these first HL-LHC background studies based on SixTrack and FLUKA simulations, highlighting the simulation setup for the design case in the HL-LHC scenario. Results of particle spectra entering the ATLAS detector region are presented for the latest study version of HL-LHC machine layout (2013).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO027  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPRO028 Energy Deposition Studies for the Hi-Lumi LHC Inner Triplet Magnets 1078
 
  • N.V. Mokhov, I.L. Rakhno, S.I. Striganov, I.S. Tropin
    Fermilab, Batavia, Illinois, USA
  • F. Cerutti, L.S. Esposito, A. Lechner
    CERN, Geneva, Switzerland
 
  Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy through the US LARP Program, and by the High Luminosity LHC project.
After operation at the nominal luminosity, the LHC is planned to be upgraded to a 5-fold increased luminosity of 5×1034 cm-2s−1. The upgrade includes replacement of the IP1/IP5 inner triplet 70-mm NbTi quadrupoles with the 150-mm coil aperture Nb3Sn quadrupoles along with the new 150-mm coil aperture NbTi dipole magnet. A detailed model of the region with these new magnets, field maps, corrector packages, segmented tungsten inner absorbers was built and implemented into the FLUKA and MARS codes. Various aspects of the new design were studied: (i) thicknesses of tungsten absorbers; (ii) beam screen interruption in interconnects; (iii) crossing angle value and orientation, etc. In the optimized configuration, the peak power density averaged over the magnet inner cable width doesn’t exceed 2 mW/cm3, safely below the quench limit. For the integrated luminosity of 3000 fb-1, the highest peak dose of 35 MGy occurs in the corrector package CP, while for other magnets, the peak dose in the innermost insulators ranges from 20 to 30 MGy. Dynamic heat loads to the triplet magnet cold mass are calculated to be on a target 10 W/m level. FLUKA and MARS results agree within 10%.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO028  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPME069 Performance Studies of the SPS Beam Dump System for HL-LHC Beams 3394
 
  • F.M. Velotti, O. Aberle, C. Bracco, E. Carlier, F. Cerutti, K. Cornelis, L. Ducimetière, B. Goddard, V. Kain, R. Losito, C. Maglioni, M. Meddahi, F. Pasdeloup, V. Senaj, G.E. Steele
    CERN, Geneva, Switzerland
 
  The Super Proton Synchrotron (SPS) beam dump system is a concern for the planned High Luminosity LHC (HL-LHC) operation. The system has initially been designed for very different beam parameters compared to those which will reign after the completion of the LHC injectors upgrade, when the SPS will have to operate with unprecedented beam brightness. This paper describes the relevant operational and failure modes of the dump system together with the expected beam loading levels. Tracking studies are presented, considering both normal operation and failure scenarios, with particular attention on the location and level of proton losses. First FLUKA investigations and thermo-mechanical analysis of the high-energy absorber block are described  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME069  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPRI011 Beam-machine Interaction at TLEP: First Evaluation and Mitigation of the Synchrotron Radiation Impact 3785
 
  • L. Lari, F. Cerutti, A. Ferrari, A. Mereghetti
    CERN, Geneva, Switzerland
  • L. Lari
    IFIC, Valencia, Spain
  • A. Mereghetti
    UMAN, Manchester, United Kingdom
 
  In the framework of post-LHC accelerator studies, TLEP is a proposed high-luminosity circular e+e collider, aimed at measuring the properties of the Higgs-boson H(126) with unprecedented accuracy, as well as those of the W boson, the Z boson and the top quark. In order to calculate the impact of synchrotron radiation, the latter has been implemented in the FLUKA code as new source term. A first account of escaping power as a function of the vacuum chamber shielding thickness, photoneutron production, and activation has been obtained for the 80km circumference 175 GeV (beam energy) TLEP option. Starting from a preliminary layout of the FODO cell and a possible dipole design, energy deposition simulations have been carried out, investigating the effectiveness of absorbers in the interconnections. The results provide inputs to improve the cell design and to support mechanical integration studies.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI011  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)