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Synergia, a multi-language, high-performance simulation environment, maximizes accelerator performance. It offers unique capabilities for synchrotrons, boosters, and storage rings, with advanced features such as multi-physics integration and multiple Poisson solvers. The Fermilab Booster simulation plays a crucial role in probing neutrino masses, requiring modeling of high-intensity proton dynamics and space-charge effects. BeamBeam3D addresses beam-beam interactions at the Tevatron, the world's highest-energy particle accelerator, enhancing luminosity by studying and mitigating beam-beam effects through self-consistent 3D modeling.
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Advanced Accelerator Simulation Panagiotis Spentzouris Fermilab Computing Division (member of the SciDAC AST project)
Accelerators are essential for the advance of science. In DOE’s “Facilities for the Future of Science” 13 of the 28 facilities are accelerators!
UC Davis Visualization, multi-resolution techniques FNAL Software Integration, Lie methods, space charge in rings, Booster simulation& experiment BNL Wakefield effects, Space charge in rings, BNL Booster simulation LBNL Beam-beam modeling, space charge in linacs & rings, parallel Poisson solvers, collisions M=e:f2: e:f3: e:f4:… N=A-1 M A U. Maryland Lie Methods in Accelerator Physics, MaryLie LANL High order optics, beam expts, collisions, multi-language support, statistical methods SLAC Ellectromagnetic component modeling UCLA Parallel PIC Frameworks SciDAC AST project(Accelerator Science & Technology)
SciDAC AST project goals • Develop and apply an advanced, comprehensive, high-performance simulation environment to solve challenging problems and to enable new discoveries in accelerator science & technology. • maximize performance of existing and optimize design of future accelerators
Synergia • Multi-language, extensible, parallel PIC framework • Incorporates multi-physics; state-of-the-art numerical libraries, solvers, physics modules Humane user interface and job creation/monitoring tools
Unique capabilities for synchrotrons, boosters, and storage rings • Multi-bunch capability • Multiple Poisson solvers • FFT, multigrid (PETSc) • Multi-turn injection • Ramping rf and magnet modeling • Active feedback modeling Longitudinal phase space shows halo & space-charge “drag” during bunch merge Synergia used in international space charge benchmark effort lead by I.Hofmann (PAC'05) From test suite: comparison w/ analytical result (J. Comp. Phys, 211,1, 2005)
Synergia performance • Utilized NERSC SP3 and Linux clusters Millions of macro-particles on hundredths of processors
Fermilab’s accelerator complex Tevatron Booster Main Injector
The Fermilab Booster The Booster is a rapid cycling machine (15Hz) accelerating protons from 400 MeV to 8 GeV The success of the quest to understand the nature and properties of neutrino masses at Fermilab depends on the Booster. Multi-particle dynamics effects, such as space charge are responsible for machine losses which limit performance
High intensity proton driver modeling • Problem:optimize accelerator performance • Problem size(FNAL Booster example): • 6×1012 protons circulating for 20,000 turns • ~100 electromagnetic elements in accelerator • Need to model the beam's self-interaction • Need to understand observed beamcharacteristics and losses • simulationrequires 106 to 107 macro-particles
Booster simulation details • Self-consistent 3D space-charge • High order magnetic optics • 33x33x257 grid, ~5M particles • boundary conditions • longitudinal periodic • transverse closed • Realistic model • multi-turn injection • machine ramping with position feedback Multi-bunch modelling in 3D • follow 5 200 MHz Linac micro-bunches in a 37.8 MHz PhS slice.
Synergia to study and optimize beam quality on normal operating conditions • compare to turn-by-turn beam profiles • 3D model enables study of phase space correlations
Space charge effects on resonances Less charge more charge Synergia simulation Data, machine running on resonance
Beam evolution on resonance:how close to a resonance can we operate?
Requirements for end to end Booster simulation • Computational effort: ~ Nturns× Nbunches× Nkicks×{parameters} • for 20,000 turns → 20 days • for multi-bunch simulation with smoothing, effective Nbunches ~10 • need ~100× current capability and improved scalability • continuing R&D for solvers with better performance and scalability
The Tevatron is the highest energy particle accelerator in the world; it accelerates protons and antiprotons up to 1 TeV (trillion electron volt). The two beams circulate together and collide at the detector locations. As the beams pass through each other, each beam’s charge affects the other beam, reducing performance. We need to study and understand these “Beam-Beam” effects to maximize Tevatron luminosity. BeamBeam3D: a 3D, self consistent code Can model multiple bunches!
But first verify model: beam-beam force couples transverse and longitudinal dynamics, so effect can be tested by comparing to FFT of the bunch motion in dedicated experiments. VEP-II accelerator, dedicated to beam measurements