IPAC2013 - List of Authors (Vlachoudis, V.)

Paper

Title

Page

Simulations and Measurements of Cleaning with 100 MJ Beams in the LHC

52

R. Bruce, R.W. Aßmann, V. Boccone, C. Bracco, M. Cauchi, F. Cerutti, D. Deboy, A. Ferrari, L. Lari, A. Marsili, A. Mereghetti, E. Quaranta, S. Redaelli, G. Robert-Demolaize, A. Rossi, B. Salvachua, E. Skordis, G. Valentino, V. Vlachoudis, Th. Weiler, D. Wollmann
CERN, Geneva, Switzerland
L. Lari
IFIC, Valencia, Spain
E. Quaranta
Politecnico/Milano, Milano, Italy
G. Valentino
University of Malta, Information and Communication Technology, Msida, Malta

The CERN Large Hadron Collider is routinely storing proton beam intensities of more than 100 MJ, which puts extraordinary demands on the control of beam losses to avoid quenches of the superconducting magnets. Therefore, a detailed understanding of the LHC beam cleaning is required. We present tracking and shower simulations of the LHC's multi-stage collimation system and compare with measured beam losses, which allow us to conclude on the predictive power of the simulations.

Slides MOODB202 [6.343 MB]

MOPWO028

Recent Developments and Future Plans for SixTrack

948

R. De Maria, R. Bruce, R. Calaga, L. Deniau, M. Fjellstrom, M. Giovannozzi, L. Lari, Y.I. Levinsen, E. McIntosh, A. Mereghetti, D. Pastor Sinuela, S. Redaelli, H. Renshall, A. Rossi, F. Schmidt, R. Tomás, V. Vlachoudis
CERN, Geneva, Switzerland
R. Appleby, D.R. Brett
UMAN, Manchester, United Kingdom
D. Banfi, J. Barranco
EPFL, Lausanne, Switzerland
B. Dalena
CEA/IRFU, Gif-sur-Yvette, France
L. Lari
IFIC, Valencia, Spain
V. Previtali
Fermilab, Batavia, USA
G. Robert-Demolaize
BNL, Upton, Long Island, New York, USA

Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.
SixTrack is a symplectic 6D tracking code routinely used to simulate single particle trajectories in high energy circular machines like the LHC and RHIC. The paper presents the developments recently implemented and those foreseen for extending the physics models: exact Hamiltonian, different ions and charge states, RF multipoles, non-linear fringe fields, Taylor maps, e-lenses, ion scattering. Moreover new functionalities are also added like variable number of tracked particles, time dependent strengths, GPU computations with a refactoring of the core structure. The developments will benefit studies on the LHC and SPS, for collimation efficiency, ion operations, failure scenarios and HL-LHC design.

TUPFI022

Power Load from Collision Debris on the LHC Point 8 Insertion Magnets Implied by the LHCb Luminosity Increase

1382

L.S. Esposito, F. Cerutti, A. Lechner, A. Mereghetti, A.A. Patapenka, V. Vlachoudis
CERN, Geneva, Switzerland
A. Mereghetti
UMAN, Manchester, United Kingdom
A.A. Patapenka
JIPNR-Sosny NASB, Minsk, Belarus

LHCb is aiming to upgrade its goal peak luminosity up to a value of 2 10³³ cm^-2 s⁻¹ after LS2. We investigate the collision debris impact on the machine elements by extensive FLUKA simulations, showing that the present machine layout is substantially compatible with such a luminosity goal. In particular the installation of a TAS (Target Absorber ofSecondaries, installed in front of the final focus Q1-Q3 quadrupole triplet in the LHC high luminosity insertions) turns out not to be necessary on the basis of the expected peak power deposition in the Q1 superconducting coils. A warm protection may be desirable to further reduce heat load and dose on the D2 recombination dipole, due to the absence of the TAN (Target Absorber of Neutrals, present in Point 1 and 5).

TUPFI027

Energy Deposition Studies for Fast Losses during LHC Injection Failures

1397

A. Lechner, A. Alnuaimi, C. Bracco, F. Cerutti, A. Christov, L.S. Esposito, N.V. Shetty, V. Vlachoudis
CERN, Geneva, Switzerland

Several instances of injection kicker magnet (MKI) failures have occurred in the first years of LHC operation, leading to misinjections or to accidental kicks of circulating bunches. In a few cases, MKI modules imparted a partial or an increased beam deflection, resulting in grazing bunch impact on beam-intercepting devices and consequently leading to significant secondary showers to downstream accelerator elements. In this study, we investigate different failure occurrences where miskicked bunches were incident on the injection beam stopper (TDI) and on one of the auxiliary injection collimators (TCLIB), respectively. FLUKA shower calculations were performed to quantify the energy deposition in superconducting magnets. Different sections of the LHC insertion regions 2 and 8 were studied, including the separation dipole and the inner triplet downstream of the TDI as well as matching section and dispersion suppressor adjacent to the TCLIB. The obtained results are evaluated in view of quench and damage limits.

WEPEA064

SixTrack-Fluka Active Coupling for the Upgrade of the SPS Scrapers

2657

A. Mereghetti, F. Cerutti, R. De Maria, B. Goddard, V. Kain, M. Meddahi, Ö. Mete, Y. Papaphilippou, D. Pastor Sinuela, V. Vlachoudis
CERN, Geneva, Switzerland
R. Appleby
UMAN, Manchester, United Kingdom

The LHC Injectors Upgrade (LIU) Project aims at upgrading the systems in the LHC injection chain, to reliably deliver the beams required by the High-Luminosity LHC (HL-LHC). Essential for the clean injection into the LHC, the SPS scrapers are one of the important systems under revision. In order to take into account of the effect of betatron and longitudinal beam dynamics on energy deposition patterns, and nuclear and Coulomb scattering in the absorbing medium onto loss patterns, the SixTrack and Fluka codes have been coupled, profiting from the best of the refined physical models they respectively embed. The coupling envisages an active exchange of tracked particles between the two codes at each turn, and an on-line aperture check in SixTrack, in order to estimate the local cleaning inefficiency of the system. Knob-like, time-dependent strengths have been implemented in SixTrack, since the designed scraper system foresees the use of a magnetic bump. The study is intended to assess the robustness of the proposed scraper as well as its effectiveness with respect to the desired performance.

THPFI062

Design of Air-cooled Beam Dump for Extraction Line of PS Booster

3436

A. Perillo-Marcone, T. Antonakakis, M. Battistin, M.A. Czapski, G.W. Mason, E.M. Nowak, A. Sarrió Martínez, S. Sgobba, V. Venturi, V. Vlachoudis
CERN, Geneva, Switzerland

A new beam dump has been designed, which withstands the future proton beam extracted from the PS Booster at CERN, consisting of up to 10¹⁴ protons per pulse at 2 GeV after its upgrade in 2018/2019. In order to be able to efficiently release the deposited heat, the new dump will be made out of a single cylindrical block of a copper alloy and be cooled by forced ventilation. In order to determine the energy density distribution deposited by the beam in the dump, Monte Carlo simulations were performed using FLUKA, and thermo-mechanical analyses carried out by importing the energy density into Ansys. In addition, CFD simulations of the airflow were carried out in order to accurately estimate the heat transfer convection coefficient on the surface of the dump. In this paper we describe the design process and highlight the constraints of integrating a new dump for increased beam power into the existing facility.

Paper	Title	Page
MOODB202	Simulations and Measurements of Cleaning with 100 MJ Beams in the LHC	52
	R. Bruce, R.W. Aßmann, V. Boccone, C. Bracco, M. Cauchi, F. Cerutti, D. Deboy, A. Ferrari, L. Lari, A. Marsili, A. Mereghetti, E. Quaranta, S. Redaelli, G. Robert-Demolaize, A. Rossi, B. Salvachua, E. Skordis, G. Valentino, V. Vlachoudis, Th. Weiler, D. Wollmann CERN, Geneva, Switzerland L. Lari IFIC, Valencia, Spain E. Quaranta Politecnico/Milano, Milano, Italy G. Valentino University of Malta, Information and Communication Technology, Msida, Malta
	The CERN Large Hadron Collider is routinely storing proton beam intensities of more than 100 MJ, which puts extraordinary demands on the control of beam losses to avoid quenches of the superconducting magnets. Therefore, a detailed understanding of the LHC beam cleaning is required. We present tracking and shower simulations of the LHC's multi-stage collimation system and compare with measured beam losses, which allow us to conclude on the predictive power of the simulations.
	Slides MOODB202 [6.343 MB]

MOPWO028	Recent Developments and Future Plans for SixTrack	948
	R. De Maria, R. Bruce, R. Calaga, L. Deniau, M. Fjellstrom, M. Giovannozzi, L. Lari, Y.I. Levinsen, E. McIntosh, A. Mereghetti, D. Pastor Sinuela, S. Redaelli, H. Renshall, A. Rossi, F. Schmidt, R. Tomás, V. Vlachoudis CERN, Geneva, Switzerland R. Appleby, D.R. Brett UMAN, Manchester, United Kingdom D. Banfi, J. Barranco EPFL, Lausanne, Switzerland B. Dalena CEA/IRFU, Gif-sur-Yvette, France L. Lari IFIC, Valencia, Spain V. Previtali Fermilab, Batavia, USA G. Robert-Demolaize BNL, Upton, Long Island, New York, USA
	Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404. SixTrack is a symplectic 6D tracking code routinely used to simulate single particle trajectories in high energy circular machines like the LHC and RHIC. The paper presents the developments recently implemented and those foreseen for extending the physics models: exact Hamiltonian, different ions and charge states, RF multipoles, non-linear fringe fields, Taylor maps, e-lenses, ion scattering. Moreover new functionalities are also added like variable number of tracked particles, time dependent strengths, GPU computations with a refactoring of the core structure. The developments will benefit studies on the LHC and SPS, for collimation efficiency, ion operations, failure scenarios and HL-LHC design.

TUPFI022	Power Load from Collision Debris on the LHC Point 8 Insertion Magnets Implied by the LHCb Luminosity Increase	1382
	L.S. Esposito, F. Cerutti, A. Lechner, A. Mereghetti, A.A. Patapenka, V. Vlachoudis CERN, Geneva, Switzerland A. Mereghetti UMAN, Manchester, United Kingdom A.A. Patapenka JIPNR-Sosny NASB, Minsk, Belarus
	LHCb is aiming to upgrade its goal peak luminosity up to a value of 2 10³³ cm^-2 s⁻¹ after LS2. We investigate the collision debris impact on the machine elements by extensive FLUKA simulations, showing that the present machine layout is substantially compatible with such a luminosity goal. In particular the installation of a TAS (Target Absorber ofSecondaries, installed in front of the final focus Q1-Q3 quadrupole triplet in the LHC high luminosity insertions) turns out not to be necessary on the basis of the expected peak power deposition in the Q1 superconducting coils. A warm protection may be desirable to further reduce heat load and dose on the D2 recombination dipole, due to the absence of the TAN (Target Absorber of Neutrals, present in Point 1 and 5).

TUPFI027	Energy Deposition Studies for Fast Losses during LHC Injection Failures	1397
	A. Lechner, A. Alnuaimi, C. Bracco, F. Cerutti, A. Christov, L.S. Esposito, N.V. Shetty, V. Vlachoudis CERN, Geneva, Switzerland
	Several instances of injection kicker magnet (MKI) failures have occurred in the first years of LHC operation, leading to misinjections or to accidental kicks of circulating bunches. In a few cases, MKI modules imparted a partial or an increased beam deflection, resulting in grazing bunch impact on beam-intercepting devices and consequently leading to significant secondary showers to downstream accelerator elements. In this study, we investigate different failure occurrences where miskicked bunches were incident on the injection beam stopper (TDI) and on one of the auxiliary injection collimators (TCLIB), respectively. FLUKA shower calculations were performed to quantify the energy deposition in superconducting magnets. Different sections of the LHC insertion regions 2 and 8 were studied, including the separation dipole and the inner triplet downstream of the TDI as well as matching section and dispersion suppressor adjacent to the TCLIB. The obtained results are evaluated in view of quench and damage limits.

WEPEA064	SixTrack-Fluka Active Coupling for the Upgrade of the SPS Scrapers	2657
	A. Mereghetti, F. Cerutti, R. De Maria, B. Goddard, V. Kain, M. Meddahi, Ö. Mete, Y. Papaphilippou, D. Pastor Sinuela, V. Vlachoudis CERN, Geneva, Switzerland R. Appleby UMAN, Manchester, United Kingdom
	The LHC Injectors Upgrade (LIU) Project aims at upgrading the systems in the LHC injection chain, to reliably deliver the beams required by the High-Luminosity LHC (HL-LHC). Essential for the clean injection into the LHC, the SPS scrapers are one of the important systems under revision. In order to take into account of the effect of betatron and longitudinal beam dynamics on energy deposition patterns, and nuclear and Coulomb scattering in the absorbing medium onto loss patterns, the SixTrack and Fluka codes have been coupled, profiting from the best of the refined physical models they respectively embed. The coupling envisages an active exchange of tracked particles between the two codes at each turn, and an on-line aperture check in SixTrack, in order to estimate the local cleaning inefficiency of the system. Knob-like, time-dependent strengths have been implemented in SixTrack, since the designed scraper system foresees the use of a magnetic bump. The study is intended to assess the robustness of the proposed scraper as well as its effectiveness with respect to the desired performance.

THPFI062	Design of Air-cooled Beam Dump for Extraction Line of PS Booster	3436
	A. Perillo-Marcone, T. Antonakakis, M. Battistin, M.A. Czapski, G.W. Mason, E.M. Nowak, A. Sarrió Martínez, S. Sgobba, V. Venturi, V. Vlachoudis CERN, Geneva, Switzerland
	A new beam dump has been designed, which withstands the future proton beam extracted from the PS Booster at CERN, consisting of up to 10¹⁴ protons per pulse at 2 GeV after its upgrade in 2018/2019. In order to be able to efficiently release the deposited heat, the new dump will be made out of a single cylindrical block of a copper alloy and be cooled by forced ventilation. In order to determine the energy density distribution deposited by the beam in the dump, Monte Carlo simulations were performed using FLUKA, and thermo-mechanical analyses carried out by importing the energy density into Ansys. In addition, CFD simulations of the airflow were carried out in order to accurately estimate the heat transfer convection coefficient on the surface of the dump. In this paper we describe the design process and highlight the constraints of integrating a new dump for increased beam power into the existing facility.