IPAC2014 - Classification: 06 Instrumentation, Controls, Feedback & Operational Aspects / T22 Reliability, Operability

Paper	Title	Page
MOOCB02	A Common Operation Metrics for Third Generation Light Sources	56
	A. Lüdeke PSI, Villigen PSI, Switzerland M. Bieler DESY, Hamburg, Germany J.-F. Lamarre SOLEIL, Gif-sur-Yvette, France M. Pont CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	High reliability is a very important goal for third generation light sources. Very often the beam availability is used as the operation metrics to measure the reliability of the accelerator. A survey at several light sources revealed that the calculation of this statistics varies significantly between facilities. This prevents a useful comparison of their reliabilities. The authors propose a specific metrics for the reliability of third generation light sources; a metrics that will allow a detailed and meaningful comparison of these particle accelerators.
	Slides MOOCB02 [0.701 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOOCB02
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THPRI014	Modular Stand-Alone Pulse Current Measurement System for Kicker and Septa at BESSY II and MLS	3794
	O. Dressler, J. Kuszynski, M. Markert HZB, Berlin, Germany
	Funding: Work supported by German Bundesministerium für Bildung und Forschung and Land Berlin. Pulse current measurement systems are introduced for all pulsed deflection magnets in the BESSY II and MLS storage rings which acquire data autonomously. The measured pulse currents are displayed locally or remotely as single values or graphs. The data acquisition systems utilize commercial PXI chassis by National Instruments (NI), controllers and 2-channel 14bit, 100MHz high-speed digitizer cards. Measurement routines are programmed with LabVIEW 2012. Special in-house custom made ‘CA-Lab’ client software provides interface for the independent systems to write values into pre-assigned process variables of the EPICS control system. The retrieved data can be displayed in the machine control system and stored in a data archive. This allows shot to shot assessment of the pulse currents for accelerator operation and troubleshooting as well as long term data evaluation in correlation with other relevant machine parameters. This report also describes the set-up for the pulse current measurements and the structured programming for the data acquisition. Limits of the applied measurement technique and experience with the information gained for the accelerator operation will be explained.
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THPRI015	DAΦNE Transfer Line for KLOE-2 Physics Run	3797
	A. De Santis, B. Buonomo, S. Cantarella, P. Ciuffetti, G. Di Pirro, A. Drago, L.G. Foggetta, A. Ghigo, C. Milardi, R. Ricci, U. Rotundo, M. Serio, A. Stecchi, A. Stella INFN/LNF, Frascati (Roma), Italy A. Michelotti Consorzio Laboratorio Nicola Cabibbo, Frascati, Italy
	The transfer lines of the DAΦNE accelerator complex have been revised and optimized in view of the forthcoming KLOE-2 physics run. The transfer lines consolidation activities involved low level systems, diagnostics tools and control system hardware modifications for the magnetic element switching polarity during the injection procedure. Transfer lines optics has been reviewed and optimized as well by a systematic study based on a MAD-X model. The work done determined a substantial improvement in the transfer lines stability and reproducibility, speeded up the injection procedure with a considerable reduction on the background hitting the experimental detector during the beam injection process.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI015
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THPRI016	Pulse Based Data Archive System and Analysis for Current and Beam Loss Monitors in the J-PARC RCS	3800
	N. Hayashi, S. Hatakeyama, K. Yamamoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	The data archive system in the J-PARC 25-Hz Rapid-Cycling Synchrotron (RCS) records the beam intensity and the beam loss monitor (BLM) pattern for all pulses. The system is based on the common memory and utilizes the timing system of the J-PARC. Although its time resolution is limited, it is useful to detect rare events or phenomena appearing with only higher accelerator repetition. Using these data, the stability of the beam intensity, particularly ion source can be examined. The relation between BLM patterns and its causes can be studied pulse-by-pulse basis and it would make use of future improvements.
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THPRI019	Reliability and Availability Modeling for Accelerator Driven Facilities	3803
	O. Rey Orozko, E. Bargalló, A. Nordt ESS, Lund, Sweden A. Apollonio, R. Schmidt CERN, Geneva, Switzerland
	Accelerator driven facilities are and will have to be designed to a very high level of reliability and beam availability to meet expectations of the users and experiments. In order to fulfill these demanding requirements on reliability and overall beam availability, statistical models have been developed. We compare different statistical reliability models as well as tools in terms of their performance, capacity and user-friendliness. In addition we also benchmarked some of the existing models. We will present in detail a tool being used for LHC and LINAC4 which is based on the commercially available software package Isograph and a tool using Excel, which was developed in house for ESS-systems. The impact of an early reliability modeling on the design of mission critical systems will be presented as well.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI019
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THPRI020	Availability Studies for Linac4 and Machine Protection Requirements for Linac4 Commissioning	3807
	A. Apollonio, S. Gabourin, C. Martin, B. Mikulec, B. Puccio, J.L. Sanchez Alvarez, D. Wollmann, M. Zerlauth CERN, Geneva, Switzerland
	Linac4 is one of the key elements in the upgrade program of the LHC injector complex at CERN, assuring beams with higher bunch intensities and smaller emittance for the LHC and many other physics experiments on the CERN site. Due to the demand of continuous operation, the expected availability of Linac4 needs to be carefully studied already during its design phase. In this paper an overview of the relevant systems impacting on Linac4 machine availability is given: the various system failure modes are outlined as well as their impact on the total yearly machine downtime. Machine Protection Systems (MPS) play a significant role in reducing the risk associated to each failure mode and are therefore important for reaching the target availability. The Linac4 MPS requirements, with particular focus on the different commissioning phases, are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI020
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THPRI022	The Accelerator Reliability Forum	3813
	A. Lüdeke PSI, Villigen PSI, Switzerland R. Giachino CERN, Geneva, Switzerland L. Hardy ESRF, Grenoble, France
	A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum (http://reliability.forumotion.com). This contribution will describe the forum and advertise it's usage in the community.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI022
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THPRI024	Finding Your Happy-User-Index	3816
	A. Lüdeke PSI, Villigen PSI, Switzerland
	Reliability is defined as the ability of a system or component to perform its required functions under stated conditions for a specified period of time. If we are talking about accelerator reliability then we have to know what the required functions are. Many accelerator facilities restrict their analysis to the beam availability: how reliable is beam provided to the users? We will show that this metrics is often not fully adequate. Specific metrics can be much more useful to allow you to optimize your facility to the needs of your users. The three accelerator user facilities at PSI will serve as examples for these happy-user-indexes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI024
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THPRI025	Accelerator Reliability Reporting at the Swiss Light Source	3819
	A. Lüdeke PSI, Villigen PSI, Switzerland
	Third generation light sources do aim for a very high reliability of the accelerator. This contribution describes the reliability reporting of the Swiss Light Source at the Paul Scherrer Institut, as it has been performed in the past decade. We will highlight the importance of a formal reporting on the accelerator reliability to support the long term optimization of the reliability of an accelerator facility.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI025
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THPRI026	A Review on Accelerator Operator Training	3822
	A. Lüdeke, E. Zimoch PSI, Villigen PSI, Switzerland
	Operators of accelerator facilities have to be trained in order to safely operate their machines. While the amount of training varies between the different types of accelerators, many best-practices could be applied to the training of operators for a variety of different facilities. The aim of our study is to survey the best-practices for operator training for a larger number of accelerator facilities. The results may provide useful insights to advance the training-plans for operators of particle accelerators.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI026
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THPRI027	Automated Conditioning System for Siemens Novel Electrostatic Accelerator	3825
	H. von Jagwitz-Biegnitz JAI, Oxford, United Kingdom P. Beasley, O. Heid, T. Kluge Siemens AG, Erlangen, Germany D.C. Faircloth STFC/RAL, Chilton, Didcot, Oxon, United Kingdom R.G. Selway Inspired Engineering Ltd, Climping, United Kingdom
	Siemens has proposed a novel compact DC electrostatic tandem accelerator to produce protons of a few MeV and is currently commissioning a prototype at the Rutherford Appleton Laboratory. The geometry of the accelerator involves large surfaces which are exposed to high electric fields and therefore need long procedures for conditioning. An automated system for conditioning has been developed. It reacts quicker to breakdowns than a human operator could do, thus being more effective and also reduces the time spent by research staff on the conditioning.
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THPRI028	Acoustic Spark Localization for the 201 MHz RF Cavity	3828
	P.G. Lane, Y. Torun Illinois Institute of Technology, Chicago, Illinois, USA E. Behnke, I.Y. Levine Indiana University South Bend, South Bend, USA D.W. Peterson Fermilab, Batavia, Illinois, USA P. Snopok IIT, Chicago, Illinois, USA
	Funding: Work supported by U.S. Department of Energy Current designs for muon cooling channels require high-gradient RF cavities to be placed in solenoidal magnetic fields in order to contain muons with large transverse emittances. It has been found that doing so reduces the threshold at which RF cavity breakdown occurs. To aid the effort to study RF cavity breakdown in magnetic fields it would be helpful to have a diagnostic tool which can detect breakdown and localize the source of the breakdown inside the cavity. We report here on the experiment setup for localizing sparks in an RF cavity by using piezoelectric transducers and on preparation for data collection on a 201.25 MHz vacuum cavity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI028
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Paper

Title

Page

A Common Operation Metrics for Third Generation Light Sources

56

A. Lüdeke
PSI, Villigen PSI, Switzerland
M. Bieler
DESY, Hamburg, Germany
J.-F. Lamarre
SOLEIL, Gif-sur-Yvette, France
M. Pont
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

High reliability is a very important goal for third generation light sources. Very often the beam availability is used as the operation metrics to measure the reliability of the accelerator. A survey at several light sources revealed that the calculation of this statistics varies significantly between facilities. This prevents a useful comparison of their reliabilities. The authors propose a specific metrics for the reliability of third generation light sources; a metrics that will allow a detailed and meaningful comparison of these particle accelerators.

Slides MOOCB02 [0.701 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOOCB02

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THPRI014

Modular Stand-Alone Pulse Current Measurement System for Kicker and Septa at BESSY II and MLS

3794

O. Dressler, J. Kuszynski, M. Markert
HZB, Berlin, Germany

Funding: Work supported by German Bundesministerium für Bildung und Forschung and Land Berlin.
Pulse current measurement systems are introduced for all pulsed deflection magnets in the BESSY II and MLS storage rings which acquire data autonomously. The measured pulse currents are displayed locally or remotely as single values or graphs. The data acquisition systems utilize commercial PXI chassis by National Instruments (NI), controllers and 2-channel 14bit, 100MHz high-speed digitizer cards. Measurement routines are programmed with LabVIEW 2012. Special in-house custom made ‘CA-Lab’ client software provides interface for the independent systems to write values into pre-assigned process variables of the EPICS control system. The retrieved data can be displayed in the machine control system and stored in a data archive. This allows shot to shot assessment of the pulse currents for accelerator operation and troubleshooting as well as long term data evaluation in correlation with other relevant machine parameters. This report also describes the set-up for the pulse current measurements and the structured programming for the data acquisition. Limits of the applied measurement technique and experience with the information gained for the accelerator operation will be explained.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI014

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THPRI015

DAΦNE Transfer Line for KLOE-2 Physics Run

3797

A. De Santis, B. Buonomo, S. Cantarella, P. Ciuffetti, G. Di Pirro, A. Drago, L.G. Foggetta, A. Ghigo, C. Milardi, R. Ricci, U. Rotundo, M. Serio, A. Stecchi, A. Stella
INFN/LNF, Frascati (Roma), Italy
A. Michelotti
Consorzio Laboratorio Nicola Cabibbo, Frascati, Italy

The transfer lines of the DAΦNE accelerator complex have been revised and optimized in view of the forthcoming KLOE-2 physics run. The transfer lines consolidation activities involved low level systems, diagnostics tools and control system hardware modifications for the magnetic element switching polarity during the injection procedure. Transfer lines optics has been reviewed and optimized as well by a systematic study based on a MAD-X model. The work done determined a substantial improvement in the transfer lines stability and reproducibility, speeded up the injection procedure with a considerable reduction on the background hitting the experimental detector during the beam injection process.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI015

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THPRI016

Pulse Based Data Archive System and Analysis for Current and Beam Loss Monitors in the J-PARC RCS

3800

N. Hayashi, S. Hatakeyama, K. Yamamoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

The data archive system in the J-PARC 25-Hz Rapid-Cycling Synchrotron (RCS) records the beam intensity and the beam loss monitor (BLM) pattern for all pulses. The system is based on the common memory and utilizes the timing system of the J-PARC. Although its time resolution is limited, it is useful to detect rare events or phenomena appearing with only higher accelerator repetition. Using these data, the stability of the beam intensity, particularly ion source can be examined. The relation between BLM patterns and its causes can be studied pulse-by-pulse basis and it would make use of future improvements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI016

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THPRI019

Reliability and Availability Modeling for Accelerator Driven Facilities

3803

O. Rey Orozko, E. Bargalló, A. Nordt
ESS, Lund, Sweden
A. Apollonio, R. Schmidt
CERN, Geneva, Switzerland

Accelerator driven facilities are and will have to be designed to a very high level of reliability and beam availability to meet expectations of the users and experiments. In order to fulfill these demanding requirements on reliability and overall beam availability, statistical models have been developed. We compare different statistical reliability models as well as tools in terms of their performance, capacity and user-friendliness. In addition we also benchmarked some of the existing models. We will present in detail a tool being used for LHC and LINAC4 which is based on the commercially available software package Isograph and a tool using Excel, which was developed in house for ESS-systems. The impact of an early reliability modeling on the design of mission critical systems will be presented as well.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI019

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THPRI020

Availability Studies for Linac4 and Machine Protection Requirements for Linac4 Commissioning

3807

A. Apollonio, S. Gabourin, C. Martin, B. Mikulec, B. Puccio, J.L. Sanchez Alvarez, D. Wollmann, M. Zerlauth
CERN, Geneva, Switzerland

Linac4 is one of the key elements in the upgrade program of the LHC injector complex at CERN, assuring beams with higher bunch intensities and smaller emittance for the LHC and many other physics experiments on the CERN site. Due to the demand of continuous operation, the expected availability of Linac4 needs to be carefully studied already during its design phase. In this paper an overview of the relevant systems impacting on Linac4 machine availability is given: the various system failure modes are outlined as well as their impact on the total yearly machine downtime. Machine Protection Systems (MPS) play a significant role in reducing the risk associated to each failure mode and are therefore important for reaching the target availability. The Linac4 MPS requirements, with particular focus on the different commissioning phases, are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI020

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THPRI022

The Accelerator Reliability Forum

3813

A. Lüdeke
PSI, Villigen PSI, Switzerland
R. Giachino
CERN, Geneva, Switzerland
L. Hardy
ESRF, Grenoble, France

A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum (http://reliability.forumotion.com). This contribution will describe the forum and advertise it's usage in the community.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI022

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THPRI024

Finding Your Happy-User-Index

3816

A. Lüdeke
PSI, Villigen PSI, Switzerland

Reliability is defined as the ability of a system or component to perform its required functions under stated conditions for a specified period of time. If we are talking about accelerator reliability then we have to know what the required functions are. Many accelerator facilities restrict their analysis to the beam availability: how reliable is beam provided to the users? We will show that this metrics is often not fully adequate. Specific metrics can be much more useful to allow you to optimize your facility to the needs of your users. The three accelerator user facilities at PSI will serve as examples for these happy-user-indexes.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI024

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPRI025

Accelerator Reliability Reporting at the Swiss Light Source

3819

A. Lüdeke
PSI, Villigen PSI, Switzerland

Third generation light sources do aim for a very high reliability of the accelerator. This contribution describes the reliability reporting of the Swiss Light Source at the Paul Scherrer Institut, as it has been performed in the past decade. We will highlight the importance of a formal reporting on the accelerator reliability to support the long term optimization of the reliability of an accelerator facility.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI025

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THPRI026

A Review on Accelerator Operator Training

3822

A. Lüdeke, E. Zimoch
PSI, Villigen PSI, Switzerland

Operators of accelerator facilities have to be trained in order to safely operate their machines. While the amount of training varies between the different types of accelerators, many best-practices could be applied to the training of operators for a variety of different facilities. The aim of our study is to survey the best-practices for operator training for a larger number of accelerator facilities. The results may provide useful insights to advance the training-plans for operators of particle accelerators.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI026

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THPRI027

Automated Conditioning System for Siemens Novel Electrostatic Accelerator

3825

H. von Jagwitz-Biegnitz
JAI, Oxford, United Kingdom
P. Beasley, O. Heid, T. Kluge
Siemens AG, Erlangen, Germany
D.C. Faircloth
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
R.G. Selway
Inspired Engineering Ltd, Climping, United Kingdom

Siemens has proposed a novel compact DC electrostatic tandem accelerator to produce protons of a few MeV and is currently commissioning a prototype at the Rutherford Appleton Laboratory. The geometry of the accelerator involves large surfaces which are exposed to high electric fields and therefore need long procedures for conditioning. An automated system for conditioning has been developed. It reacts quicker to breakdowns than a human operator could do, thus being more effective and also reduces the time spent by research staff on the conditioning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI027

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THPRI028

Acoustic Spark Localization for the 201 MHz RF Cavity

3828

P.G. Lane, Y. Torun
Illinois Institute of Technology, Chicago, Illinois, USA
E. Behnke, I.Y. Levine
Indiana University South Bend, South Bend, USA
D.W. Peterson
Fermilab, Batavia, Illinois, USA
P. Snopok
IIT, Chicago, Illinois, USA

Funding: Work supported by U.S. Department of Energy
Current designs for muon cooling channels require high-gradient RF cavities to be placed in solenoidal magnetic fields in order to contain muons with large transverse emittances. It has been found that doing so reduces the threshold at which RF cavity breakdown occurs. To aid the effort to study RF cavity breakdown in magnetic fields it would be helpful to have a diagnostic tool which can detect breakdown and localize the source of the breakdown inside the cavity. We report here on the experiment setup for localizing sparks in an RF cavity by using piezoelectric transducers and on preparation for data collection on a 201.25 MHz vacuum cavity.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI028

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