ICAP2012 - List of Keywords (scattering)

Paper	Title	Other Keywords	Page
MOABC3	Simulating the LHC Collimation System with the Accelerator Physics Library MERLIN, and Loss Map Results	proton, collimation, simulation, optics	12
	J. Molson, R. Appleby, M. Serluca, A.M. Toader UMAN, Manchester, United Kingdom R.J. Barlow University of Huddersfield, Huddersfield, United Kingdom
	Funding: FP7 EUCARD Cockcroft Institute We present large scale simulations of the LHC collimation system using the MERLIN code for calculations of loss maps, currently using up to 1.5·10⁹ halo particles. In the dispersion suppressors following the collimation regions, protons that have undergone diffractive interactions can be lost into the cold magnets. This causes radiation damage and could possibly cause a magnet quench in the future with higher stored beam energies. In order to correctly simulate the loss rates in these regions, a high statistics physics simulation must be created that includes both accurate beam physics, and an accurate description of the scattering of a 7 TeV proton in bulk materials. The current version includes the ability to simulate new possible materials for upgraded collimators, and advances to beam-collimator interactions, including proton-nucleus interactions using the Donnachie-Landshoff Regge-Pomeron scattering model. Magnet alignment and field errors are included, in addition to collimator jaw alignment errors, and their effects on the beam losses are systematically estimated. Collimator wakefield simulations are now fully parallel via MPI, and many other speed enhancements have been made.
	Slides MOABC3 [8.057 MB]

MOSCC3	Low-energy p-He and mu-He Simulation in Geant4	simulation, proton, plasma, electron	40
	Y. Bao PSI, Villigen, Switzerland
	The frictional cooling method is one of the most promising methods on cooling a muon beam. Several frictional cooling schemes have been simulated in Geant4 to be efficient to produce intense muon beams. Frictional cooling works at a low energy range, where the energy loss (momentum transfer) from elastic collision is not negligible. In this paper, the p-He collision process is implemented into Geant4 and the simulation results are compared to the literature data. The cross section is then scaled for mu-He interaction, which will provide more accurate Geant4 simulations at low energies.
	Slides MOSCC3 [0.665 MB]

THACI1	Lumped Equivalent Models of Complex RF Structures	HOM, impedance, RF-structure, factory	245
	T. Flisgen, J. Heller, U. van Rienen Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
	Funding: partly funded by EU FP7 Research Infrastructure Grant No. 227579 The prediction of RF properties of complex accelerating structures is an important issue in computational accelerator physics. This paper describes the derivation of state space equations for complex structures based on real eigenmodes of sections of the decomposed complex structure. The state space equations enable the calculation of system responses due to port excitations by means of standard ordinary differential equation solvers. Therefore, the state space equations are referred to as lumped equivalent models of such complex RF structures. Besides fast computation of system responses, the equivalent models enable the calculation of secondary quantities such as external quality factors. The present contribution discusses theoretical aspects and illustrates an application example.
	Slides THACI1 [1.538 MB]

Paper

Title

Other Keywords

Page

MOABC3

Simulating the LHC Collimation System with the Accelerator Physics Library MERLIN, and Loss Map Results

proton, collimation, simulation, optics

12

J. Molson, R. Appleby, M. Serluca, A.M. Toader
UMAN, Manchester, United Kingdom
R.J. Barlow
University of Huddersfield, Huddersfield, United Kingdom

Funding: FP7 EUCARD Cockcroft Institute
We present large scale simulations of the LHC collimation system using the MERLIN code for calculations of loss maps, currently using up to 1.5·10⁹ halo particles. In the dispersion suppressors following the collimation regions, protons that have undergone diffractive interactions can be lost into the cold magnets. This causes radiation damage and could possibly cause a magnet quench in the future with higher stored beam energies. In order to correctly simulate the loss rates in these regions, a high statistics physics simulation must be created that includes both accurate beam physics, and an accurate description of the scattering of a 7 TeV proton in bulk materials. The current version includes the ability to simulate new possible materials for upgraded collimators, and advances to beam-collimator interactions, including proton-nucleus interactions using the Donnachie-Landshoff Regge-Pomeron scattering model. Magnet alignment and field errors are included, in addition to collimator jaw alignment errors, and their effects on the beam losses are systematically estimated. Collimator wakefield simulations are now fully parallel via MPI, and many other speed enhancements have been made.

Slides MOABC3 [8.057 MB]

MOSCC3

Low-energy p-He and mu-He Simulation in Geant4

simulation, proton, plasma, electron

40

Y. Bao
PSI, Villigen, Switzerland

The frictional cooling method is one of the most promising methods on cooling a muon beam. Several frictional cooling schemes have been simulated in Geant4 to be efficient to produce intense muon beams. Frictional cooling works at a low energy range, where the energy loss (momentum transfer) from elastic collision is not negligible. In this paper, the p-He collision process is implemented into Geant4 and the simulation results are compared to the literature data. The cross section is then scaled for mu-He interaction, which will provide more accurate Geant4 simulations at low energies.

Slides MOSCC3 [0.665 MB]

THACI1

Lumped Equivalent Models of Complex RF Structures

HOM, impedance, RF-structure, factory

245

T. Flisgen, J. Heller, U. van Rienen
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany

Funding: partly funded by EU FP7 Research Infrastructure Grant No. 227579
The prediction of RF properties of complex accelerating structures is an important issue in computational accelerator physics. This paper describes the derivation of state space equations for complex structures based on real eigenmodes of sections of the decomposed complex structure. The state space equations enable the calculation of system responses due to port excitations by means of standard ordinary differential equation solvers. Therefore, the state space equations are referred to as lumped equivalent models of such complex RF structures. Besides fast computation of system responses, the equivalent models enable the calculation of secondary quantities such as external quality factors. The present contribution discusses theoretical aspects and illustrates an application example.

Slides THACI1 [1.538 MB]