Paper  Title  Other Keywords  Page 

MOSBI1  Automatic Computer Algorithms for Beambased Setup of the LHC Collimators  alignment, feedback, injection, collimation  15 


Funding: FP7 EuCARD  WP8 ColMat Beambased setup of the LHC collimators is necessary to establish the beam centers and beam sizes at the collimator locations and determine the operational settings during various stages of the LHC machine cycle. Automatic software algorithms have been successful in reducing the costly beam time required for the alignment, as well as significantly reducing human error. In this paper, the beambased alignment procedure is described, and the design of algorithms such as a BLM feedback loop, parallel collimator alignment, pattern recognition of BLM loss spikes, automatic loss threshold selection and coarse BPMinterpolation guided alignment is explained. A comparison on the alignment results from the 2010 to the 2012 LHC runs is presented to illustrate the improvements achieved with the automatic algorithms. 

Slides MOSBI1 [10.572 MB]  
MOSBC3  An Implementation of the Virtual Accelerator in the Tango Control System  lattice, simulation, diagnostics, storagering  23 


Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.0012213/09 Integration of simulating codes into the control system gives a possibility to improve machine operation. Providing tools for making computations directly within the control system and letting exchange data between the control system and models is a way of simplifying the whole process of calculating and applying machine's operational parameters as well as keeping track of them. In addition, having socalled an online model could be useful for system diagnostic and faults detection, especially when the objective approach is considered. The concept of the Virtual Accelerator will be presented as well as its implementation for the Tango control system as it is planned to be used for both facilities: the Solaris in Kraków, Poland and the MAX IV in Lund, Sweden. This includes the ModelServer tango device, the simplified C/C++ Tango API to be used with codes like Tracy and the tango2elegant script providing easy solution for integrating the Elegant tool with the Tango. 

Slides MOSBC3 [2.232 MB]  
MOSDC2  GPGPU Implementation of Matrix Formalism for Beam Dynamics Simulation  simulation, target  59 


Matrix formalism is a map integration method for ODE solving. It allows to present solution of the system as sums and multiplications of 2indexes numeric matrix. This approach can be easy implement in parallel codes. As the most natural for matrix operation GPU architecture has been choosen. The set of the methods for beam dynamics has been implemented. Particles and envelope dynamics are supported. The computing facilities are located in St. Petersburg State University and presented by the NVIDIA Tesla clusters.  
Slides MOSDC2 [0.770 MB]  
TUAAI2  A Massively Parallel General Purpose Multiobjective Optimization Framework, Applied to Beam Dynamic Studies  simulation, emittance, status, solenoid  62 


Particle accelerators are invaluable tools for research in basic and applied sciences. The successful design, commissioning, and operation of accelerator facilities is non trivial. We implemented a framework for general simulationbased multioptimization methods automating the investigation of optimal sets of machine parameters. In order to solve the emerging, huge problems we propose a massivelyparallel master/slave approach. We employ the framework to identify optimal parameters of existing and new accelerators at PSI.  
Slides TUAAI2 [0.694 MB]  
TUSCC2  The Convergence and Accuracy of the Matrix Formalism Approximation  93  


Funding: The work is supported by Federal Targeted Program "Scientific and ScientificPedagogical Personnel of the Innovative Russia in 20092013" (Governmental Contract no. p 793) To the present time there has been developed a large number of different codes for the particles beam dynamics modeling. However, their precision, accuracy and reliability of the numerical results are not sufficiently guaranteed in the case of longterm evolution of particle beams in circular accelerators. Here we discuss convergence estimates of the matrix presentation for Lie series. We also consider some problems of the matrix formalism accuracy for constructing the evolution operator of the particle beam. In this article there is paid a special attention to problems of symplecticity and energy conservation for long time evolution of particle beams. 

Slides TUSCC2 [1.475 MB]  
WEAAI1  Bringing Largescale Analytics to Accelerators  EPICS, target, monitoring, linac  116 


The report presents a new approach for storing and processing both the accelerator control data and the experimental results. It is based on the analysis and consolidation of several modern technologies, such as the EPICS control infrastructure, the SciDB arrayoriented data management and analytics platform, the HDF5 file format, and others. The paper overviews the different features of the proposed system and the development of analytics algorithms in the context of the modern light source facilities.  
Slides WEAAI1 [2.505 MB]  
WEAAC3  Dynamics of Ferrite Cavities and their Effect on Longitudinal Dipole Oscillations  cavity, simulation, resonance, synchrotron  124 


Funding: This work is supported by the German Federal Ministry of Education and Research under grant number 06DA9028I. In a synchrotron, particles are accelerated by repeatedly passing through RF cavities. In the SIS18 synchrotron at GSI, ferrite cavities are used. Each cavity is equipped with local control systems to adjust the amplitude and phase of the accelerating field. In this paper, we consider ferrite cavities of the type that is currently used in the SIS18 at GSI and will be used in the future SIS100 which is being built in the frame of the FAIR project. We analyze the dynamics of the cavities in conjunction with their local control loops. An emphasis is put on the cavities' reaction to changes in the desired amplitude or resonant frequency. Using simulations, we show that the cavities' dynamics hardly influence longitudinal dipole oscillations, and conclude that a highlevel model for the RF cavities is sufficient. 

Slides WEAAC3 [1.055 MB]  
WEAAC4  Design of a Computer Based ResonatorSimulator for Tests of RF Control Systems  cavity, resonance, linac, beamloading  127 


Funding: supported by the BMBF contract 06DA9024I In order to test RF control systems for accelerator cavities without being dependent on available prototypes, a resonatorsimulator has been developed. The Simulator is based on a XilinxVIRTEX4 FPGAmodule and has been configured using MATLABSimulink with a special XilinxBlockset. The underlying model for this configuration is a parallel RLCcircuit that has been parameterised with common RFquantities like the resonance frequency, driving frequency, bandwidth and quality factor. This approach allows to simulate the behaviour of normal conducting cavities with quality factors up to 10^{4} as well as superconducting cavities with quality factors up to 10^{9}. Besides, it can as well be operated in a continuouswave as in a pulsed mode. We report on the mathematical model, its digital representation and on the benchmarking against real cavity behaviour. 

Slides WEAAC4 [2.540 MB]  
WEP06  Particle Tracking in Electrostatic Fields with Energy Conservation  simulation, quadrupole, storagering, lattice  149 


The key idea of the research is to consider spin dynamics in electrostatic fields. Due to the fact, that spin rotation frequency explicitly depends on velocity of the particle and its kinetic energy is changed in electrostatic fields it is important to use some technique that provides both conservation energy and symplicticity condition. An appropriate mathematical model is described and the results of numerical calculation are shown. In conclusion, fringe fields influence is examined and compared with case of ideal fields.  
WEP13  ModelBased Analysis of Digital Signal Processing Blocks in a Beam Phase Control System  synchrotron, dipole, ion, heavyion  164 


Funding: This work is supported by the German Federal Ministry of Education and Research under grant number 06DA9028I. A beam phase control system comprises digital phase detectors and band pass filters to detect coherent longitudinal dipole and higher order bunch oscillations. These digital signal processing functions can be implemented in several ways, e. g. in software or on a programmable logic device. In this paper, we consider different possible implementations and compare them in terms of their realtime performance and their system resource consumption. For the phase detectors, a software implementation is compared against different (e. g. lookup table and CORDICbased) hardware implementations. For the band pass filters, we consider software, hardware and mixed implementations. 

WEP15  Tools for Analysis and Improvement of Linac Optics Design for High Brightness Electron Beams  optics, quadrupole, focusing, emittance  170 


The optics design of single pass high brightness electron linacs usually aims at the preservation of the transverse emittance. Collective effects mainly impose constraints to the optics design such as at the lowbeta interaction points in colliders and magnetic compressors in FELs. Other constraints are from the trajectory correction scheme, performance of diagnostics, collimation systems and physical space limitations. Strong focusing is typically prescribed for all the aforementioned cases, although it may hamper the main goal of emittance preservation through the excitation of optical aberrations. Strong focusing also potentially leads, through focusing errors, to large beam optics mismatch. Based on these sometimes conflicting requirements, we have developed tools for the analysis and improvement of electron linac optics. They are based on the Elegant [1] code and allow the user to identify:
[1] M. Borland, Advanced Photon Source LS287 (2000). 

WEP16  Analytical Presentation of Space Charge Forces  spacecharge, beamtransport, focusing, optics  173 


Funding: The work is supported by Federal Targeted Programme "Scientific and ScientificPedagogical Personnel of the Innovative Russia in 20092013" (Governmental Contract no. p 793) This paper presents an analytical description of the space charge forces generated by charged particle beams. The suggested approach is based on some set of models for particle distribution function. All necessary calculations have analytical and closed form for different models for beam density distributions. These model distributions can be used for approximation of real beam distributions. The corresponding solutions are included in a general scheme of beam dynamics presentation based on the matrix formalism for Lie algebraic tools. The corresponding computer software is based on corresponding symbolic codes and some parallel technologies. In particular, as computational tools we consider GPU graphic card NVIDIA. As an example, there is considered the problem of modeling the beam dynamics for microprobe focusing systems. 

WEACI1  Design and Applications of the Bmad Library for the Simulation of Particle Beams and XRays  simulation, lattice, solenoid, quadrupole  179 


The Bmad software library has been developed for simulations of highenergy particle beams along with simulations of the xrays produced by the particle beams. Owing to its modular, objectoriented design, Bmad is now used in a number of programs at Cornell's Laboratory for ElementaryParticle Physics. This paper will discuss the design of the Bmad library. Features such as the ability to have overlapping elements, the ability to define in a lattice file the action of controlroom ‘‘knobs'', and the ability to choose from a number of different tracking options on an elementbyelement basis have all contributed to a versatile simulation environment that eases the task of programmers and users using Bmad. Also discussed is the uses that Bmad has been put to including synchrotron radiation tracking with reflections from the vacuum chamber walls, spin tracking, beam breakup instability, intrabeam scattering, etc. Besides simulation and design programs, Bmad can be used in control programs to do such things as orbit and Twiss correction calculations.  
Slides WEACI1 [1.884 MB]  
THP02  Beam Dynamics Simulations Using GPUs  simulation, ion, linac, synchrotron  227 


PATRIC is a particle tracking code used at GSI to study collective effects in the FAIR synchrotrons. Due to the need for calculationintense simulations, parallel programming methods are being explored to optimize calculation performance. Presently the tracking part of the code is parallelized using MPI, where each node represents one slice of the particles that travel through the accelerator. In this contribution different strategies will be presented to additionally employ GPUs in PATRIC and exploit their support for data parallelism without major code modifications to the original tracking code. Some consequences of using only singleprecision in beam dynamics simulations will be discussed.  
THP06  An OpenMP Parallelisation of Realtime Processing of CERN LHC Beam Position Monitor Data  target, insertion, HOM, nonlineardynamics  230 


SUSSIX is a FORTRAN program for the post processing of turnbyturn Beam Position Monitor (BPM) data, which computes the frequency, amplitude, and phase of tunes and resonant lines to a high degree of precision. For analysis of LHC BPM data a specific version run through a C steering code has been implemented in the CERN Control Centre to run on a server under the Linux operating system but became a real time computational bottleneck preventing truly online study of the BPM data. Timing studies showed that the independent processing of each BPMs data was a candidate for parallelization and the OpenMP package with its simple insertion of compiler directives was tried. It proved to be easy to learn and use, problem free and efficient in this case reaching a factor of ten reduction in realtime over twelve cores on a dedicated server. This paper reviews the problem, shows the critical code fragments with their OpenMP directives and the results obtained.  
THSCC2  Reconstruction of Velocity Field  electron, spacecharge, induction, electromagneticfields  256 


In this paper we suppose that the distribution density of particles in phase space is known. Using Liouville’s equations the problem of finding velocity field is considered as a minimization problem. Thus the problem of determination of velocity field is reduced to solving of elliptic system of EulerLagrange equations.  
Slides THSCC2 [8.701 MB]  