06 Instrumentation, Controls, Feedback & Operational Aspects

T18 Radiation Monitoring and Safety

Paper Title Page
MOPD017 G4Beamline Program for Radiation Simulations 481
 
  • K. B. Beard, T. J. Roberts
    Muons, Inc, Batavia
  • P. Degtiarenko
    Jefferson Lab, Newport News, Virginia
 
  G4beamline, a program that is an interface to the Geant4 toolkit that we have developed to simulate accelerator beamlines, is being extended with a graphical user interface to quickly and efficiently model experimental equipment and its shielding in experimental halls. The program is flexible, user friendly, and requires no programming by users, so that even complex systems can be simulated quickly. This improved user interface is of much wider application than just the shielding simulations that are the focus of this project. As an initial application, G4beamline is being extended to provide the simulations that are needed to determine the radiation sources for the proposed experiments at Jefferson Laboratory so that shielding issues can be evaluated. Since the program already has the capabilities needed to simulate the transport of all known particles, including scattering, attenuation, interactions, and decays, the extension involves implementing a user-friendly graphical user interface for specifying the simulation, and creating general detector and shielding component models and interfacing them to existing Geant4 models of the experimental halls.  
MOPD018 Energy Dependent Measurements of Gamma and Neutron Dose at ANKA 484
 
  • I. Birkel, E. Huttel, A.-S. Müller, N. J. Smale, P. Wesolowski
    FZK, Karlsruhe
 
  Gamma and neutron radiation dose rate around an electron storage ring are proportional to the number of lost particles in a certain time. They are depending on beam energy, current, lifetime and operating conditions of the storage ring. The online area monitoring network of ANKA makes it possible to measure the radiation from the decaying beam at eight stations distributed all over the ANKA hall. Measurements of the ambient dose at beam energies from 800 MeV to 2.5 GeV show higher dose rates around and in the forward direction of insertion devices and other devices with restricted horizontal or vertical aperture.  
MOPD026 Radiological Hazards Assessment for the Beam Dump of High Intensity Deuteron Accelerators 502
 
  • D. López, M. Garcia, A. Mayoral, F. Ogando, J. Sanz, P. Sauvan
    UNED, Madrid
 
  Several of the most important aspects with regards to the radiological potential hazards assessment in the beam dump of a high intensity deuteron accelerator are analyzed. Deuteron and neutron induced activation as well as neutron production for the beam dump cartridge, in order to select low activation materials; evaluation of the tritium production due to the implanted deuterium in the material and the presence of water in the cooling and local shielding systems, relevant for the associated radiotoxicity; estimation of gamma dose rate in beam-off phase in the vicinity of the cartridge, important issue for accessibility and maintenance works of the system. All these points are assessed both for normal operation and commissioning phase in the IFMIF-EVEDA accelerator prototype. Several materials are studied according to neutron production using transport codes (MCNPX and PHITS) and EAF2007 libraries. Activation calculations with ACAB code use irradiation fluxes obtained with MCNPX. Evaluation of tritium production due to implanted deuterium is calculated with SRIM-TMAP7 coupled code. Tritium in water is calculated by activation procedures. Gamma dose rate is computed with MCNPX.  
MOPD027 AMC-based Radiation Monitoring System 505
 
  • D. R. Makowski, A. Napieralski, A. Piotrowski
    TUL-DMCS, Łódź
  • S. Simrock
    DESY, Hamburg
 
  This paper reports a novel radiation monitoring system able to monitor gamma and neutron radiation in an accelerator tunnel in the nearest proximity of the electronic components of the control system. The monitoring system is designed as an Advanced Mezzanine Module (AMC) and it is dedicated for the Low Level Radio Frequency (LLRF) control system based on the Advanced Telecommunication Computing Architecture (ATCA). The AMC module is able to communicate with LLRF control system using both I2C interface defined by Intelligent Platform Management Interface (IPMI) standard and PCI Express. The measured gamma radiation dose and neutron fluence are sent to data acquisition computer using Ethernet network and stored in a database. Static Random Access Memory (SRAM) is applied as a neutron dosimeter. The principle of the detector is based on the radiation effect initiating the Single Event Upsets (SEUs) in a high density microelectronic SRAMs. A well known RadFET dosimeter is used to monitor gamma radiation.  
MOPD030 The LHC radiation monitoring system for the environment and safety: from design to operation 514
 
  • L. Scibile, D. Forkel-Wirth, H. G. Menzel, D. Perrin, G. Segura Millan, P. Vojtyla, M. Widorski
    CERN, Geneva
 
  The RAdiation Monitoring System for the Environment and Safety (RAMSES) has been installed and successfully commissioned. The system was originally designed for the Large Hadron Collider (LHC), it was extended to the CNGS and it is also planned to further extend it to the rest of the CERN accelerators. This state-of-the-art radiation monitoring and alarm system provides permanent ambient dose equivalent rates and ambient dose equivalent measurement in the underground areas as well as on the surface inside and outside the CERN perimeter; it permanently monitors air and water released from the LHC and CNGS installations; it also integrates some conventional environmental measurement such as physicochemical parameters of released water. This paper illustrates the experience gained during the various project phases outlining the problems encountered and the solutions implemented. In addition, it gives a first feedback on the operational experience gained with the CNGS.  
MOPD031 Automatic Implementation of Radiation Protection Algorithms in Programs Generated by GCC Compiler 517
 
  • A. Piotrowski, D. R. Makowski, A. Napieralski, Sz. Tarnowski
    TUL-DMCS, Łódź
 
  Radiation influence on microprocessor-based systems is serious problem especially in places like accelerators and synchrotrons, where sophisticated digital devices operate closely to the radiation source. Reliability of such systems is significantly decreased due to effects like SEU or SEFI. One of the possible solutions to increase radiation immunity of the microprocessor systems is a strict programming approach known as Software Implemented Hardware Fault Tolerance. SIHFT methods are based on the redundancy of variables or procedures. Sophisticated algorithms are used to check the correctness of control flow in application. Unfortunately, manual implementation of presented algorithms is difficult and can introduce additional problems with program functionality cased by human errors. Proposed solution is based on modifications of the source code of the C language compiler. Protection methods are applied at intermediate representation of the compiled source code. This approach makes it possible to use standard optimization algorithms during compilation. In addition, a responsibility for implementing fault tolerant is transferred to the compiler and is transparent for programmers.  
MOPD032 Neutronics Calculations to Support the SNS Accelerator Facility 520
 
  • I. I. Popova, G. W. Dodson, P. D. Ferguson, J. Galambos, F. X. Gallmeier
    ORNL, Oak Ridge, Tennessee
 
  The Spallation Neutron Source (SNS) is an accelerator driven neutron scattering facility for materials research that recently started operations. After commissioning, the facility started at low power and is presently in the process of a power ramp to reach the Megawatt power level within two years of operations, maintenance, and tuning cycles. Extensive neutronics work for shielding development and dose rate predictions was completed during design and construction for various operational and shut down scenarios. Now that the facility is successfully operating, there is still demand for neutronics analyses for radiation-protection support. This need arises from redesigning some parts of the facility, facility upgrades, designing additional structures, designing test stands for accelerator structures, and verification and code validation analyses on the basis of the measured data.  
MOPD037 Safety Testing for LHC Access System 532
 
  • F. Valentini, T. Ladzinski, P. Ninin, L. Scibile
    CERN, Geneva
 
  This paper presents the validation and verification activities carried out for the LHC Access Control and Safety System. It also presents a new strategy for the future that includes the application of formal methods based on model checking techniques, commonly used to prove the correctness of software algorithms or system functional specifications through automatic exploration of the system state space. We will show how to apply these techniques in order to automate the testing process. The paper also presents the results of the performances and the applicability of a series of tools that have been tested in order to carry out a formal correctness proof for the LHC Access System.  
MOPD038 First Radiation Monitoring Results During Elettra Booster Commissioning 535
 
  • K. Casarin, E. Quai, S. Sbarra, G. Tromba, A. Vascotto
    ELETTRA, Basovizza, Trieste
 
  The new injection system for the Elettra storage ring is based on a 100 MeV linac and a booster synchrotron, where the electron energy can be raised up to 2.5 GeV. The new machine is designed to perform full energy injection, also in top-up mode. Outside the shielding, radiation monitoring is performed through a real-time network of gamma and neutron dosimeters as well as through TLD passive dosimeters. The radiation monitors placed next to the beamlines are interlocked with the machine operation and prevent injection into the storage ring if the alarm threshold is exceeded. This paper reports the first results of the radiation monitoring performed during the new injector commissioning.  
MOPD039 The Personnel Safety System of the Elettra Booster 538
 
  • K. Casarin, L. Battistello, S. Fontanini, F. Giacuzzo, M. Lonza, E. Quai, S. Sbarra, G. Tromba, A. Vascotto, L. Zambon
    ELETTRA, Basovizza, Trieste
 
  The new injector of the Elettra storage ring is based on a 100 MeV linac feeding a 3 Hz booster synchrotron. The booster is designed to accelerate the electron beam up to the maximum energy of 2.5 GeV, providing full-energy injection into the storage ring. The Personnel Safety System (PSS) of the new injector protects personnel from radiation hazards by controlling access to restricted areas and interrupting the machine operation in case unsafe conditions occur. The system is based on Programmable Logic Controller (PLC) technology providing redundant logic in a fail-safe configuration. This paper describes the radiation safety criteria that have been defined to minimize radiation exposure hazards as well as the technology and architecture chosen for the PSS implementation.  
MOPD041 The SSRF Radiation Safety Interlock System 541
 
  • X. J. Xu, J. H. Cai, J. Cai, K. M. Fang, Z. D. Hua, X. Liu, J. H. Wang, J. Q. Xu
    SINAP, Shanghai
 
  Radiation Safety Interlock System (RSIS) for the Shanghai Synchrotron Radiation Facility (SSRF) is composed of two subsystems, the Access Control System (ACS) and the radiation containment system (RCS).The ACS prevents personnel from being exposed to the extremely high radiation inside the SSRF shielding tunnel (or called the interlock area) during machine operation. The RCS prevents personnel from being exposed to the high radiation outside a shielding tunnel during either normal or abnormal operation. The implementation of the ACS is based on the Programmable Logic Controllers, key transfer interlocking systems and IC card system. The RSIS is based on fail-safe, redundancy, multiplicity. Any violation of the RSIS will result in the inhibiting of redundant permission to the associated interlock systems, and cease the injection process and eliminate the entire stored electron beam in the SSRF. This paper describes the design philosophy, the logic, and the implementation of the RSIS at SSRF.