High Dose Irradiation of Possible FCAL Sensors at the S-DALINAC

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High Dose Irradiation of Possible FCAL Sensors at the S-DALINAC. Ch.Grah Physics and Detector Meeting DESY HH, 29.6.2006. Contents. Reminder of FCAL detector systems and motivation Testbeam at the S-DALINAC of the TU Darmstadt (12.06. -19.06.2006) Preparations - PowerPoint PPT Presentation

Transcript of High Dose Irradiation of Possible FCAL Sensors at the S-DALINAC

  • High Dose Irradiation of Possible FCAL Sensors at the S-DALINAC


    Physics and Detector Meeting DESY HH, 29.6.2006

  • ContentsReminder of FCAL detector systems and motivationTestbeam at the S-DALINAC of the TU Darmstadt (12.06. -19.06.2006)PreparationsSome pictures from the testbeamAnalysis and first resultsSummary

  • FCAL SystemLumiCal30 layer Si:W26 < < 155 mradBeamCal30 layer CVD diamond:W5 < < 28 mrad

    Forward region of LDC (V2)

  • Sensors for FCALEnergy deposition from beamstrahlung pairs in BeamCal.10-20 TeV and more depending on the beam parameters.

    Dose of up to 10MGy/aInvestigate: pCVD diamond sensors fromdifferent manufacturers (E6, IAF, Minsk) Si sensors GaAs sensorspCVD sensor from IAF12 x 12 mm2 size, 300-500m thickness,Ti/Pt/Au metallizationIAF: Fraunhofer Institute for Applied Solid-State PhysicsE6: De Beers Industrial Diamonds rebranded to Element Six in 2002pCVD: polycrystaline Chemical Vapour Deposition

  • Radiation Hardness of CVD diamondsIn our lab: so far only low dose irradiationdiamond response vs. absorbed dose (Sr90)T.Behnke et al., 2001 pCVD diamonds are radiation hard.

  • Testbeam Purpose: High Dose IrradiationIrradiate different sensor samples to high doses (>1 MGy).Use rather low energetic electrons similar to secondaries.2X06X020X0V.DrugakovEnergy spectrum of particles depositing energy in the BeamCal sensors

  • S-DALINAC of the TU DarmstadtUsing the injector line of the S-DALINAC:10 0.015 MeV and beam currents from 10 to 100 nA3 GHz electron beamenergy: 2.5 to 130 MeVintensity: 1 nA to 50 ASuperconducting DArmstadt LInear ACcelerator

  • Accelerator Hall

  • S-DALINAC LocationCCD setup

    Periodic Charge Collection Distance measurementRemote control/surveillance of beam areaTransport of sensor under HV

  • Beam AreaMonitor beam current via Faraday cup current to estimate dose.Monitor high voltage/current and temperatures.Local DAQ PC is operated remotely.

    Optimization by G4 simulation

  • G4 SimulationOptimize distanceOptimize collimator andFaraday cup sizeReduce distance to exit window

  • G4 SimulationEnergy deposition in the sensorSpatial distribution of sensor hitsStatistics (extract R = NFC/NSensor = 0.98)

  • Sensor Holderexit windowof beam linecollimator (IColl)sensor box (IDia, TDia, HV)Faraday cup (IFC, TFC)

  • Beam Area: EquipmentPower supplies and monitoringSurveillance from control roomSensor holder

    I-V conversion

  • Beam Area: Sensor (De-) Installation

  • CCD Setup Installation

  • CCD Setup Operation typical spectrum of an E6 sensorSr90 sourcePreamplifierSensor boxTrigger box&GatediscrdiscrdelayADCSr90diamondScint.PM1PM2

  • Program2 samples from E61 MGy5 MGy2 samples from IAF1 MGy5 MGy2 Si samplesboth drew high currents after ~50 kGy.E6_4p after ~5 MGy

  • Analysis and First Preliminary ResultsTuned the beam to currents in the Faraday cup of:10, 20, 50 and 100 nAThis corresponds to dose rates of:59, 118, 296, 591 kGy/hFor now assume an error of 10%.

  • ConclusionInvestigated the radiation hardness of sensors (silicon and pCVD diamond) for the calorimeters of the FCAL system of the ILC.The S-DALINAC offers an infrastructure for irradiating with a wide range of intensities and energies up to 10 MeV.Irradiated 6 samples up to doses of 1-5 MGy (at least for the diamond sensors).Analysis is ongoing. Have the opportunity to repeat such a test next year, to irradiate to even higher doses.There were some issues (beam monitoring during irradiation, sensor box design) which will be improved by then.

  • The Testbeam Crewnot on the photo:W.LangeThanks to: INTAS and the TU Darmstadt