Radiation monitoring: what do we have and what do we need?

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Radiation monitoring: what do we have and what do we need?. M. Calviani, M. Brugger, P. Peronnard, J. Saraiva, G. Spiezia (EN/STI) R2E/Availability Workshop October 2014. Summary. Use of the monitoring system Brief summary of Run I experience RadMon development Injectors monitoring - PowerPoint PPT Presentation

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Radiation monitoring: what do we have and what do we need?Radiation monitoring: what do we have and what do we need?M. Calviani, M. Brugger, P. Peronnard, J. Saraiva, G. Spiezia (EN/STI)R2E/Availability Workshop October 20141SummaryUse of the monitoring systemBrief summary of Run I experienceRadMon developmentInjectors monitoringRequirements from usersWhat would be needed for Run IIOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop2What do we use the monitoring forMeasurement of radiation levels in the machines:High energy hadron fluence (HEH)Total ionizing dose (TID)Understanding of the radiation field in the tunnel and shielded areas and support for simulation extrapolationImportant service to equipment groups for failure analysisInput/requirement for equipment designOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop3What would happen if dont have itCannot correlate equipment failure with radiation levels risk of changing equipment w/o solving the problemCannot anticipate need for equipment upgrades rad-tolerantCannot study radiation impact of changing operational parametersCannot dissociate the possible radiation sourceLimited info on eventual radiation quantity responsible for degradation (TID, NIEL, HEH)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop4Types of detectors employedOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop5LHC RadMon coverageOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop6LHCCritical areas (UJ, RR, US, UX, RE, UA)DS and start of ARCLSSExperimentsRadMon locations in DS/ARCOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop7DS/ARC (from cell 7 to 20)RadMon are placed below the interconnect between the last MB/MQ of a given cellEquipment below MB/MQ!MBMBMQMBMBMQMBMBMBcell icell i+1cell icell i+1Dedicated LHC-MD extraction of an operative ratio between BLM dose and expected HEH from RadMons = ~1 SEU count/mGyTunnel equipment (QPS, CRYO, BLM or EPC)Experience from Run I (1/5)Nice summary of Run I observation is available here Radiation levels summarized with the use of different types of detectors (RadMons, BLMs, FGCs, etc.)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop8Experience from Run I (2/5)Lesson:Important to follow-up machine operational parameters (TCL/RR)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop9Experience from Run I (3/5)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop10Lessons:BLM analysis fundamental for the DS/ARCWhen BLM/RadMon available, good agreement between themPoint 4Experience from Run I (4/5)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop11Very important to follow-up radiation monitoring following operational variationsSometimes just scaling is risky...Predictions2012Observations end 2012Decreased: TCL closedIncreased: tight collimatorsIncreased: higher cum. lumiExperience from Run I (5/5)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop12We should not forget the p-Pb and Pb-Pb runsDue to the Bound-Free Pair Production (BFPP), even for short runs, radiation levels can be up to 5 times those of a standard pp runDS cells most affected~7 months~3 daysOpen points in view of Run IIOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop1325 ns operation uncertainties:Evolution of beam-gas levels during 25 ns operation still to be fully clarifiedDuring Chamonix 2012 it was stated that pressure will not increase more than 2x with respect to 50 nsHowever experience showed that pressure variation depends strongly on real operational parametersStill an open pointOpen points in view of Run IILHC Point 4 and Point 6UX45: radiation levels in 2012 higher than expected from 2011 triggered TE/CRG relocation activitiesHow the situation will evolve with 25ns operation?UX65: still calm, as no special equipment might increase the beam-gas interactionMonitoring has been improvedOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop14RadMons developmentsOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop15During LS1 more than 100 RadMons have been installed in machines450 in totalInjectors, target area, experimental areas..LHC: ARC P1-2-5-8 + relocations for R2ERadMon v5LHCRadMon v6Experimental areas (n_TOF, AD)Injection linesRadMons developmentFeatures of v6:Remote configurabilitySelf-diagnosticRadiation resistance 3 times higherNew sensorsOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop16Advantages with respect to v5:Resolution improved by a factor of 10Reduced number of tunnel access to change settingsLonger life-timeRadMons developmentOverall resolution improvement factor of 3 to 10TID limit 3x times largerOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop17SensorSensitivity*ResolutionRange(Prev)(New-V6)Fet10050 rad/mV300 rad20 rad 1Mrad Fet100Bias14 rad/mVNA6 rad 0.4 Mrad BPW (3)4109 n/cm2/mV31010 n/cm26109n/cm21013n/cm2BPW(1)11010 n/cm2/mV71010 n/cm221010 n/cm251014 n/cm2Toshiba2106 n/cm2/count2108 n/cm22108 n/cm221011 n/cm2Cypress1.5105(8105) n/cm2/countNA1.5107(8107) n/cm241011 n/cm2BatMon versatile instrumentOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop18Where versatile installation is requiredE.g. PLC failures in LHC Point 4 and 6 requiring urgent checksValidation of the relocation strategyMeasure R-factor in critical area via voltage changeMeasurement requests for machine studiesInjectors radiation monitoringR2E up to 2012 concentrated on the LHC, in order to mitigate radiation effects for Run 1However issues are present in the injector chain as well, simply less visibleIn order to guarantee machine availability also in the future, its important to dedicate resources on it as wellInfo available at http://r2e-injectors.web.cern.ch/ October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop19Issues with present radiation monitoringOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop20BLMs (ACEM Aluminum Cathode Electron Multipliers)Saturation in critical areas, of no use for loss distributionNot calibrated to doseOngoing campaign to install LHC-type BLMs in PSB (not PS) important to be able to evaluate cumulative doseSPS ionisation chambers low granularity (1 every 32 meters)HLD (not online system)Radiation SurveysDepends on activation, cannot directly relate to rad levels for equipmentPSB example (RS vs. HLD)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop21PS example (RS vs. HLD)October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop22October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop23October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop24Injector monitoring - futureOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop25Requirements:Appropriate BLM coverage with sufficient granularity in PS/PSB/SPSRadMon installation extensionPassive dosimetryImportant to follow-up this measurements and improve analysis speedRequirements from usersOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop26A weekly report was published during 2011/2012, providing radiation levels in critical areasService to users in support of the RadWGRequirements from usersOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop27However:It was a manual system, requiring full support from the MCWG teamDifficult for users to understand levels if equipment away from the detector location interpretation/extrapolation from MCWG team neededLoss scenarios can modify radiation levels distributionsInvestment should be made to try to automatize it!Requirements from usersOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop28An attempt of realizing an online system was performed in collaboration with EN/ICEDedicated support of EN/ICE requested to revise the system LHC R2E DashboardComplex to maintain, since as of now data requires manual manipulationWhat will be needed for Run IIReactivation of the MCWG analysis teamDedicated support from the BLM team to provide cumulated doses on a weekly basisRadMon team to continue support the detectorsContinue keep track of the detectors inventory (Layout DB?)Support of the groups for fast reporting on equipment failuresContinue improving on radiation monitoring in the injectorsOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop29October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop30October 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop31Fundamental to follow-up on these, at the moment done manually!ConclusionsMonitoring is and will be an important aspects of the R2E (and Availability) activitiesIn the LHC and in the Injector chainIt is now required as a service rather than studiesPowerful instrument that allow providing a service to equipment owners in understanding radiation-related failuresOctober 2014M. Calviani: Radiation monitoring - R2E/Availability Workshop32

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