IBIC2012 - List of Authors (Dehning, B.)

Paper

Title

Page

Comparison of Three Different Concepts of High Dynamic Range and Dependability Optimised Current Measurement Digitisers for Beam Loss Systems

66

W. Viganò, B. Dehning, E. Effinger, G.G. Venturini, C. Zamantzas
CERN, Geneva, Switzerland

The first concept is based on current to frequency conversion, enhanced with an ADC for extending the dynamic range and decreasing the response time. A summary of 3 years worth of operational experience with such a system for LHC beam loss monitoring will be given. The second principle is based on an adaptive current to frequency converter implemented in an ASIC. The basic parameters of the circuit are discussed and compared with measurements. Several measures are taken to harden both circuits against single event effects and to make them tolerant for operation in radioactive environments. The third circuit is based on a fully differential integrator for enhanced dynamic range, where laboratory and test installation measurements will be presented. All circuits are designed to avoid any dead time in the acquisition and have reliability and fail safe operational considerations taken into account.

MOPA10

Diamond Detectors for LHC

71

E. Griesmayer, P. Kavrigin
CIVIDEC Instrumentation, Wien, Austria
T. Baer, B. Dehning, D. Dobos, E. Effinger, H. Pernegger
CERN, Geneva, Switzerland
M. Hempel
BTU, Cottbus, Germany

Funding: CIVIDEC Instrumentation GmbH
Diamond detectors are installed at the LHC as fast beam loss monitors. Their excellent time resolution make them a useful beam diagnostic tool for bunch-to-bunch beam loss observations, which is essential for the understanding of fast beam loss scenarios at the LHC.

MOPA12

Characterization of a Wide Dynamic-range, Radiation-tolerant Charge-digitizer ASIC for Monitoring of Beam Losses

74

G.G. Venturini, F. Anghinolfi, B. Dehning
CERN, Geneva, Switzerland
M. Kayal
EPFL, Lausanne, Switzerland

An Application Specific Integrated Circuit (ASIC) has been designed and fabricated to provide a compact solution to digitize current signals from ionization chambers and diamond detectors, employed as beam loss monitors at CERN and several other high energy physics facilities. The circuit topology has been devised to accept positive and negative currents, to have a wide dynamic range (above 120 dB), withstand radiation levels over 100kGy and offer different modes of operation, covering a broad range of applications. Furthermore, an internal conversion reference is employed in the digitization, to provide an accurate absolute measurement. This paper discusses the detailed characterization of the first prototype: linearity, radiation tolerance and temperature dependence of the conversion, as well as implications and system-level considerations regarding its use for beam instrumentation applications in a high energy physics facility.

MOPB79

Design of a High-precision Fast Wire Scanner for the SPS at CERN

259

R. Veness, N. Chritin, B. Dehning, J. Emery, J.F. Herranz Alvarez, M. Koujili, S. Samuelsson, J.L. Sirvent Blasco
CERN, Geneva, Switzerland

Studies are going on of a new wire scanner concept. All moving parts are inside the beam vacuum and it is specified for use in all the machines across the CERN accelerator complex. Key components have been developed and tested. Work is now focussing on the installation of a prototype for test in the Super Proton Synchrotron (SPS) accelerator. This article presents the specification of the device and constraints on the design for integration in the different accelerators at CERN. The design issues of the mechanical components are discussed and optimisation work shown. Finally, the prototype design, integrating the several components into the vacuum tank is presented.

TUPA09

System Architecture for Measuring and Monitoring Beam Losses in the Injector Complex at CERN

347

C. Zamantzas, M. Alsdorf, B. Dehning, S. Jackson, M. Kwiatkowski, W. Viganò
CERN, Geneva, Switzerland

The strategy for beam setup and machine protection of the accelerators at the European Organisation for Nuclear Research (CERN) is mainly based on its Beam Loss Monitoring (BLM) systems. For their upgrade to higher beam energies and intensities, a new BLM system is under development with the aim of providing faster measurement updates with higher dynamic range and the ability to accept more types of detectors as input compared to its predecessors. In this paper, the architecture of the complete system is explored giving an insight to the design choices made to provide a highly reconfigurable system that is able to fulfil the different requirements of each accelerator using reprogrammable devices.

TUPA29

Implementation of an FPGA Based System Survey and Diagnostic Reader with the Aim to Increase the System Dependability

409

M. Alsdorf, B. Dehning, M. Kwiatkowski, W. Viganò, C. Zamantzas
CERN, Geneva, Switzerland

The operation and machine protection of accelerators practically rely on their underlying instrumentation systems and a failure of any of those systems could pose a significant impact on the overall reliability and availability. In order to improve the detection and in some cases the prevention of failures, a survey mechanism could be integrated to the system that collects crucial information about the current system status through a number of acquisition modules. The implementation and integration of such a method is presented with the aim to standardize the implementation, where the acquisition modules share a common build and are connected through a standardized interface to a survey reader. The reader collects regularly data and controls the readout intervals. The information collected from these modules is used locally in the FPGA device to identify critical system failures and results in an immediate failsafe reaction with the data also transmitted and stored in external databases for offline analysis.

TUPA30

Development of a Beam Loss Measurement System with Gigabit Ethernet Readout at CERN

414

M. Kwiatkowski, M. Alsdorf, E. Angelogiannopoulos, B. Dehning, S. Jackson, W. Viganò, C. Zamantzas
CERN, Geneva, Switzerland

The aim of the BLM Dual Polarity card under development at the European Organisation for Nuclear Research (CERN) is to measure and digitise with high precision the current produced by several types of beam loss detectors. In its default configuration, it is expected to provide data to the processing electronics through two point-to-point connections with bidirectional multi-gigabit optical links. For the development phases as well as later serving as a stand-alone measurement system, its reconfigurable FPGA device is exploited to provide a soft-core CPU with a custom made server. This server, running on the CPU, will expose through the Gigabit Ethernet connection and the TCP/IP protocol different types of data in the network. In this paper the development of the system and of the communication protocol is explored as well as the accompanying client application that is realised with the purpose of commanding, collecting storing and viewing the different types of data.

TUPA31

A Real-Time FPGA Based Algorithm for the Combination of Beam Loss Acquisition Methods used for Measurement Dynamic Range Expansion

419

M. Kwiatkowski, M. Alsdorf, B. Dehning, W. Viganò, C. Zamantzas
CERN, Geneva, Switzerland

The aim of the Beam Loss Monitoring Dual Polarity (BLEDP) module under development at the European Organisation for Nuclear Research (CERN) is to measure and digitise with high precision the current produced by several types of beam loss detectors. The BLEDP module consists of eight analogue channels each with a fully differential integrator and an accompanying 16 bit ADC at the output of each analogue integrator. The on-board FPGA device controls the integral periods, instructs the ADC devices to perform measurements at the end of each period and collects the measurements. In the next stage it combines the number of charge and discharge cycles accounted in the last interval together with the cycle fractions observed using the ADC samples to produce a digitized high precision value of the charges collected. This paper describes briefly the principle of the fully differential integrator and focuses on the algorithm employed to process the digital data.

TUPB61

The First Experience with the LHC Beam Gas Ionisation Monitor

489

M. Sapinski, W. Andreazza, B. Dehning, A. Guerrero, M. Patecki, R. Versteegen
CERN, Geneva, Switzerland

The Beam Gas Ionisation Monitors (BGI) are used to continuously measure the beam size at the LHC. This paper describes the detectors and their operation and discusses the issues encountered during the commissioning. It also discusses the various calibration procedures used to correct for non-uniformity of Multi-Channel plates and to correct the beam size for effects affecting the electron trajectory after ionisation.

WEIB02

Review of Reliability Concepts Applied to Beam Loss Monitoring Systems

550

B. Dehning
CERN, Geneva, Switzerland

Beam loss measurement systems are often used for the protection of equipment against the damage caused by impacting particles creating secondary showers and their energy dissipation in the matter. Depending on the acceptable consequences and the frequency of particle impact events on equipment reliability requirements are scaling accordingly. Increasing reliability often leads to more complex systems. The downside of complexity is a reduction of availability, therefore an optimum has to be found for these conflicting requirements. A detailed review of selected concepts and solutions from real-life examples will be given to show approaches used in various parts of the system from the sensors, signal processing, and software implementations up to the requirements for operation and documentation.

Slides WEIB02 [4.609 MB]

Paper	Title	Page
MOPA09	Comparison of Three Different Concepts of High Dynamic Range and Dependability Optimised Current Measurement Digitisers for Beam Loss Systems	66
	W. Viganò, B. Dehning, E. Effinger, G.G. Venturini, C. Zamantzas CERN, Geneva, Switzerland
	The first concept is based on current to frequency conversion, enhanced with an ADC for extending the dynamic range and decreasing the response time. A summary of 3 years worth of operational experience with such a system for LHC beam loss monitoring will be given. The second principle is based on an adaptive current to frequency converter implemented in an ASIC. The basic parameters of the circuit are discussed and compared with measurements. Several measures are taken to harden both circuits against single event effects and to make them tolerant for operation in radioactive environments. The third circuit is based on a fully differential integrator for enhanced dynamic range, where laboratory and test installation measurements will be presented. All circuits are designed to avoid any dead time in the acquisition and have reliability and fail safe operational considerations taken into account.

MOPA10	Diamond Detectors for LHC	71
	E. Griesmayer, P. Kavrigin CIVIDEC Instrumentation, Wien, Austria T. Baer, B. Dehning, D. Dobos, E. Effinger, H. Pernegger CERN, Geneva, Switzerland M. Hempel BTU, Cottbus, Germany
	Funding: CIVIDEC Instrumentation GmbH Diamond detectors are installed at the LHC as fast beam loss monitors. Their excellent time resolution make them a useful beam diagnostic tool for bunch-to-bunch beam loss observations, which is essential for the understanding of fast beam loss scenarios at the LHC.

MOPA12	Characterization of a Wide Dynamic-range, Radiation-tolerant Charge-digitizer ASIC for Monitoring of Beam Losses	74
	G.G. Venturini, F. Anghinolfi, B. Dehning CERN, Geneva, Switzerland M. Kayal EPFL, Lausanne, Switzerland
	An Application Specific Integrated Circuit (ASIC) has been designed and fabricated to provide a compact solution to digitize current signals from ionization chambers and diamond detectors, employed as beam loss monitors at CERN and several other high energy physics facilities. The circuit topology has been devised to accept positive and negative currents, to have a wide dynamic range (above 120 dB), withstand radiation levels over 100kGy and offer different modes of operation, covering a broad range of applications. Furthermore, an internal conversion reference is employed in the digitization, to provide an accurate absolute measurement. This paper discusses the detailed characterization of the first prototype: linearity, radiation tolerance and temperature dependence of the conversion, as well as implications and system-level considerations regarding its use for beam instrumentation applications in a high energy physics facility.

MOPB79	Design of a High-precision Fast Wire Scanner for the SPS at CERN	259
	R. Veness, N. Chritin, B. Dehning, J. Emery, J.F. Herranz Alvarez, M. Koujili, S. Samuelsson, J.L. Sirvent Blasco CERN, Geneva, Switzerland
	Studies are going on of a new wire scanner concept. All moving parts are inside the beam vacuum and it is specified for use in all the machines across the CERN accelerator complex. Key components have been developed and tested. Work is now focussing on the installation of a prototype for test in the Super Proton Synchrotron (SPS) accelerator. This article presents the specification of the device and constraints on the design for integration in the different accelerators at CERN. The design issues of the mechanical components are discussed and optimisation work shown. Finally, the prototype design, integrating the several components into the vacuum tank is presented.

TUPA09	System Architecture for Measuring and Monitoring Beam Losses in the Injector Complex at CERN	347
	C. Zamantzas, M. Alsdorf, B. Dehning, S. Jackson, M. Kwiatkowski, W. Viganò CERN, Geneva, Switzerland
	The strategy for beam setup and machine protection of the accelerators at the European Organisation for Nuclear Research (CERN) is mainly based on its Beam Loss Monitoring (BLM) systems. For their upgrade to higher beam energies and intensities, a new BLM system is under development with the aim of providing faster measurement updates with higher dynamic range and the ability to accept more types of detectors as input compared to its predecessors. In this paper, the architecture of the complete system is explored giving an insight to the design choices made to provide a highly reconfigurable system that is able to fulfil the different requirements of each accelerator using reprogrammable devices.

TUPA29	Implementation of an FPGA Based System Survey and Diagnostic Reader with the Aim to Increase the System Dependability	409
	M. Alsdorf, B. Dehning, M. Kwiatkowski, W. Viganò, C. Zamantzas CERN, Geneva, Switzerland
	The operation and machine protection of accelerators practically rely on their underlying instrumentation systems and a failure of any of those systems could pose a significant impact on the overall reliability and availability. In order to improve the detection and in some cases the prevention of failures, a survey mechanism could be integrated to the system that collects crucial information about the current system status through a number of acquisition modules. The implementation and integration of such a method is presented with the aim to standardize the implementation, where the acquisition modules share a common build and are connected through a standardized interface to a survey reader. The reader collects regularly data and controls the readout intervals. The information collected from these modules is used locally in the FPGA device to identify critical system failures and results in an immediate failsafe reaction with the data also transmitted and stored in external databases for offline analysis.

TUPA30	Development of a Beam Loss Measurement System with Gigabit Ethernet Readout at CERN	414
	M. Kwiatkowski, M. Alsdorf, E. Angelogiannopoulos, B. Dehning, S. Jackson, W. Viganò, C. Zamantzas CERN, Geneva, Switzerland
	The aim of the BLM Dual Polarity card under development at the European Organisation for Nuclear Research (CERN) is to measure and digitise with high precision the current produced by several types of beam loss detectors. In its default configuration, it is expected to provide data to the processing electronics through two point-to-point connections with bidirectional multi-gigabit optical links. For the development phases as well as later serving as a stand-alone measurement system, its reconfigurable FPGA device is exploited to provide a soft-core CPU with a custom made server. This server, running on the CPU, will expose through the Gigabit Ethernet connection and the TCP/IP protocol different types of data in the network. In this paper the development of the system and of the communication protocol is explored as well as the accompanying client application that is realised with the purpose of commanding, collecting storing and viewing the different types of data.

TUPA31	A Real-Time FPGA Based Algorithm for the Combination of Beam Loss Acquisition Methods used for Measurement Dynamic Range Expansion	419
	M. Kwiatkowski, M. Alsdorf, B. Dehning, W. Viganò, C. Zamantzas CERN, Geneva, Switzerland
	The aim of the Beam Loss Monitoring Dual Polarity (BLEDP) module under development at the European Organisation for Nuclear Research (CERN) is to measure and digitise with high precision the current produced by several types of beam loss detectors. The BLEDP module consists of eight analogue channels each with a fully differential integrator and an accompanying 16 bit ADC at the output of each analogue integrator. The on-board FPGA device controls the integral periods, instructs the ADC devices to perform measurements at the end of each period and collects the measurements. In the next stage it combines the number of charge and discharge cycles accounted in the last interval together with the cycle fractions observed using the ADC samples to produce a digitized high precision value of the charges collected. This paper describes briefly the principle of the fully differential integrator and focuses on the algorithm employed to process the digital data.

TUPB61	The First Experience with the LHC Beam Gas Ionisation Monitor	489
	M. Sapinski, W. Andreazza, B. Dehning, A. Guerrero, M. Patecki, R. Versteegen CERN, Geneva, Switzerland
	The Beam Gas Ionisation Monitors (BGI) are used to continuously measure the beam size at the LHC. This paper describes the detectors and their operation and discusses the issues encountered during the commissioning. It also discusses the various calibration procedures used to correct for non-uniformity of Multi-Channel plates and to correct the beam size for effects affecting the electron trajectory after ionisation.

WEIB02	Review of Reliability Concepts Applied to Beam Loss Monitoring Systems	550
	B. Dehning CERN, Geneva, Switzerland
	Beam loss measurement systems are often used for the protection of equipment against the damage caused by impacting particles creating secondary showers and their energy dissipation in the matter. Depending on the acceptable consequences and the frequency of particle impact events on equipment reliability requirements are scaling accordingly. Increasing reliability often leads to more complex systems. The downside of complexity is a reduction of availability, therefore an optimum has to be found for these conflicting requirements. A detailed review of selected concepts and solutions from real-life examples will be given to show approaches used in various parts of the system from the sensors, signal processing, and software implementations up to the requirements for operation and documentation.
	Slides WEIB02 [4.609 MB]