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Radiation protection aspects for the Phase II upgrade. S. Roesler, C. Theis, C. Urscheler , Heinz Vincke, Helmut Vincke. Outline. A quick introduction to FLUKA Residual dose equivalent predictions by FLUKA Evolution parameters for simulation Focus on Inner Detectors
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Radiation protection aspects for the Phase II upgrade S. Roesler, C. Theis, C. Urscheler, Heinz Vincke, Helmut Vincke
Outline • A quick introduction to FLUKA • Residual dose equivalent predictions by FLUKA • Evolution parameters for simulation • Focus on Inner Detectors • Scaling factors for Phase II upgrade • Measured dose rates and comparison to FLUKA simulations for ATLAS • ALARA: • ALARA rules • Optimization during design (ActiWiz) Forum on Tracking Detector Mechanics 2013, 19-21 June
What is FLUKA1,2? • General purpose tool for calculating transport and interactions of particles with matter • Applications: accelerator shielding to target design, activation, dosimetry, detector design, etc. A. Ferrari, P.R. Sala, A. Fasso and J. Ranft.FLUKA: amulti-particle transport code. s.l. : CERN 2005-10, INFN/TC_05/11, SLAC-R-773, 2005. G. Battistoni, S. Muraro, P.R. Sala, F. Cerutti, A. Ferrari, S. Roesler, A. Fasso, J. Ranft. The FLUKA code: Description and benchmarking. Proceedings of the Hadronic Shower Simulation Workshop 2006. s.l. : Fermilab 6-8Sept 2006, AIP Conference Proceeding 896, 31-49 (2007). Forum on Tracking Detector Mechanics 2013, 19-21 June
Physics in FLUKA1,2 interaction and transport of: • About 60 particles (non-nuclei) • Photons and electrons from 1 keV to thousands of TeV • Hadrons up to 20 TeV (up to 10 PeV by linking DPMJET3) • Neutrons down to thermal energies (260 energy groups for E < 20MeV) • Heavy ions • In complex geometries and presence of magnetic fields A. Ferrari, P.R. Sala, A. Fasso and J. Ranft.FLUKA: a multi-particletransport code. s.l. : CERN 2005-10, INFN/TC_05/11, SLAC-R-773, 2005. G. Battistoni, S. Muraro, P.R. Sala, F. Cerutti, A. Ferrari, S. Roesler, A. Fasso, J. Ranft. The FLUKA code: Description and benchmarking. Proceedings of the Hadronic Shower Simulation Workshop 2006. s.l. : Fermilab 6-8Sept 2006, AIP Conference Proceeding 896, 31-49 (2007). S.Roesler, R.Engel, J.Ranft. The Monte Carlo Event Generator DPMJET-III. s.l. : Springer-Verlag Berlin, 1033-1038 (2001), 2000. Vols. in Proceedings of the Monte Carlo 2000 Conference Lisbon, October 23-26. Forum on Tracking Detector Mechanics 2013, 19-21 June
Pixel ATLAS model in FLUKA Original version by: A. Ferrari, modified and updated by many other authors • Symmetry in φ and with regard to xy plane at IP • Including magnetic field from toroid • Reduced implementation of services and support structure TAS Endcap calorimeter Endcap toroid Q1 10 m Pictured with FLAIR4 Forum on Tracking Detector Mechanics 2013, 19-21 June (4) V.Vlachoudis"FLAIR: A Powerful But User Friendly Graphical Interface For FLUKA"Proc. Int. Conf. on Mathematics, Computational Methods & Reactor Physics (M&C 2009), Saratoga Springs, New York, 2009
CMS model in FLUKA Original version by: M. Huhtinen, modified and updated by many other authors HE • Symmetry in φ and with regard to XY plane in IP except for interface to LHC • Including magnetic field from solenoid and from Q1 • Reduced implementation of services and support structure • No Castor Blockhouse HF Pixel TAS Q1 10 m Pictured with FLAIR4 Forum on Tracking Detector Mechanics 2013, 19-21 June (4) V.Vlachoudis"FLAIR: A Powerful But User Friendly Graphical Interface For FLUKA"Proc. Int. Conf. on Mathematics, Computational Methods & Reactor Physics (M&C 2009), Saratoga Springs, New York, 2009
Operational scenario up to Phase II L.Rossi / Workshop on remote manipulations, 6.Mai 2013 Assumptions on the operational parameters as obtained from ATLAS and CMS Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual dose rates LS3 – ATLAS 1 week 6 months 0.5uSv/h 0.15uSv/h one year one month 0.3uSv/h 0.11uSv/h Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual dose rates LS3 – CMS 1 week 6 months 5uSv/h 1uSv/h one year one month 3uSv/h 0.7uSv/h Forum on Tracking Detector Mechanics 2013, 19-21 June EDMS-Nr: 1281113
ATLAS - inner detectors implementation in FLUKA • beampipe: • Be for z<3.5m, aluminium for z>3.5m • No bellows included • Pixel layout • : by P. Miyagawa TRT SCT Pixel Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS - Residual Dose in vicinity of Inner detectors LS1 1 week 4 weeks 6 months 1 year Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS - Residual Dose in vicinity of Inner detectors LS3 1 week 4 weeks 6 months 1 year Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS - Scaling factors inner detectors (0<r<1m) LS3 LS1 Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS - Scaling factors inner detectors (0<r<1m) LS3 LS1 Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS - Scaling factors LS1 to LS3 Forum on Tracking Detector Mechanics 2013, 19-21 June
CMS - inner detectors implementation in FLUKA HCAL barrel • beampipe: • Be for z<2m, steel for z>2m • Pixel layout • : by I.Kurochkin • Tracker layout: • Si layers, average material for services and air ECAL barrel ECAL endcap Silicon tracker Bellows (Fe, Cr, Ni) Pictured with FLAIR Forum on Tracking Detector Mechanics 2013, 19-21 June
CMS - Residual Dose in vicinity of Inner detectors LS1 1 week 4 weeks 6 months 1 year Forum on Tracking Detector Mechanics 2013, 19-21 June
CMS - Residual Dose in vicinity of Inner detectors LS3 1 week 4 weeks 6 months 1 year Forum on Tracking Detector Mechanics 2013, 19-21 June
CMS - Scaling factors inner detectors (0<r<1m) LS3 LS1 Forum on Tracking Detector Mechanics 2013, 19-21 June
CMS - Scaling factors inner detectors (0<r<1m) LS3 LS1 Forum on Tracking Detector Mechanics 2013, 19-21 June
CMS - Scaling factors inner detectors Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS – Bechmark to measured dose rates forward regionLS1 Measurement points 1-5: Forum on Tracking Detector Mechanics 2013, 19-21 June
ATLAS – Benchmark to measured dose rates forward regionLS1 Measurement points 1-5 @ 40cm: Forum on Tracking Detector Mechanics 2013, 19-21 June Measurement data from 21.2.2013 in courtesy of O.Beltramello, N. Conan, S. Malyukov, G. Spigo
ATLAS – Benchmark to measured dose ratesLS1 Measurement points 6-8 @ 10cm: Barrel 6680 (EBC) EBC 40 cm 90 cm 180 cm VI VA 6 7 8 Measurement data from 6.3.2013 in courtesy of O.Beltramello, N. Conan, S. Malyukov, G. Spigo Dose equivalent rate prediction for VA by Z. Zajacova Forum on Tracking Detector Mechanics 2013, 19-21 June
Classification of non-designated and radiation areas at CERN EDMS-Nr: 810149 Forum on Tracking Detector Mechanics 2013, 19-21 June
General Principles of Radiation Protection • Justification • any exposure of persons to ionizing radiation has to be justified • 2) Limitation • the personal doses have to be kept below the legal limits • 3) Optimization • the personal doses and collective doses have to be kept as low as reasonable achievable (ALARA) IEFC workshop 2011, 21 - 24 March
Optimization – CERN safety code F Forum on Tracking Detector Mechanics 2013, 19-21 June
Optimization – ALARA procedure Optimization is legal requirement if accumulated annual dose exceeds 100 μSv (ALARA) Optimization includes: Optimization is done by the Experiment safety group (RSO, Glimos) in cooperation with CERN-RP group • work coordination • work procedures • handling tools • design • material Group 1 criteria 5 mSv Group 1 criteria: determine ALARA Level classification Group 2 criteria: can be used by RP/RSO to increase/decrease classification depending on radiological risk analysis Formal work-and-dose-planning(DIMR) as from ALARA Level 2 ALARA committee if ALARA Level 3 Group 2 criteria Forum on Tracking Detector Mechanics 2013, 19-21 June
Optimization during design – Intervention doses Optimization starts with the design! Methodology: Calculation of residual dose rate maps Calculation of individual and collective intervention doses Revision of design and/or work scenario • for cooling times typical for interventions on the respective component • based on nominal operational parameters • definition of geometry and materials as detailed as needed (and available) • Done by Experiment safety group (RSO, RPE, Glimos) approved by RP • based on as realistic as possible work scenarios, including locations, duration, number of • persons involved,.. • identification of cooling times below which work will be impossible • (design criterion: 2 mSv/intervention/year) • start with work steps that give highest individual or collective doses • consider optimization measures (distance, tooling, material choices, etc.) • identify if remote handling is possible Forum on Tracking Detector Mechanics 2013, 19-21 June
Optimization during design – Material choice Goal: • Minimize doses received by personnel during maintenance and repair • Reduce costs for waste disposal • Consider radiological hazards in the choice of construction materials Tool to optimize material choices: ActiWiz5 • Computer codeimplementing a risk model using pre-calculated FLUKA results. Considers external exposure • and radioactive waste disposal • Provides radiological hazard assessment for arbitrary materials within a few seconds • Catalogue6, produced with ActiWiz, listing pre-processed risk factors for typical accelerator construction • materials as well as natural elements • Web-based catalogue (ActiWeb) allowing user friendly comparison of pre-processed materials • Web-site: https://actiwiz.web.cern.ch/ (5) H. Vincke, C. Theis: “ActiWiz - optimizing your nuclide inventory at proton accelerators with a computer code, Proceedings of the ICRS-12 & RPSD 2012 conference, Nara, Progress in Nuclear Science and Technology, in press, 2013. (6) R. Froeschl, S, Sqobba, C. Theis, F. La Torre, H. Vincke, N. Walter: “Radiological hazard classification of material in CERN’s accelerators”, EDMS-Nr: 1184236 Forum on Tracking Detector Mechanics 2013, 19-21 June
ActiWiz web-based catalog Pictures from: ActiWebby F.L. Pereira, C. Theis, H. Vincke, (c) CERN 2011 Forum on Tracking Detector Mechanics 2013, 19-21 June
ActiWiz web-based catalog ActiWiz is designed for LHC accelerator scenarios, Keep in mind when using for experiments Pictures from: ActiWebby F.L. Pereira, C. Theis, H. Vincke, (c) CERN 2011 Forum on Tracking Detector Mechanics 2013, 19-21 June
ActiWiz– Material Catalogue Materials not available in the catalogue can be processed with ActiWiz Forum on Tracking Detector Mechanics 2013, 19-21 June
Optimization during design – ActiWiz Forum on Tracking Detector Mechanics 2013, 19-21 June
Summary and Conclusion • Ambient dose equivalent rate around inner detectors for Phase II: up to 100 µSv/h after several months of cool down time • Scaling factors from LS1 to LS3 between 8-12 for ATLAS and 12-24 for CMS, depending on the cooling time • Benchmark with ATLAS measurements indicates factor of 2 for most locations with exceptions at local hotspots due to inaccurate geometry implementation • Future work: update FLUKA geometries including changes during LS1 (aluminiumbeampipe, implementation of missing flanges etc.) Forum on Tracking Detector Mechanics 2013, 19-21 June
Backup slides LS2 Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual Dose in vicinity of ATLAS Inner detectors LS2 1 week 4 weeks 6 months 1 year Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual Dose CMS Inner Detectors LS2 1 week 4 weeks 6 months 1 year Forum on Tracking Detector Mechanics 2013, 19-21 June
BACKUP SLIDES ATLAS • Residual dose only pixel • Residual dose only ID-SCT-TRT Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual Dose ATLAS Pixel LS1 Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual Dose ATLAS Pixel LS3 Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual Dose ATLAS ID-SCT-TRT LS1 Forum on Tracking Detector Mechanics 2013, 19-21 June
Residual Dose ATLAS ID-SCT-TRT LS3 Forum on Tracking Detector Mechanics 2013, 19-21 June
Waste zoning CMS https://edms.cern.ch/document/1286671/1 Forum on Tracking Detector Mechanics 2013, 19-21 June
Waste zoning ATLAS Forum on Tracking Detector Mechanics 2013, 19-21 June https://edms.cern.ch/document/1286661/1