high dose irradiation of possible fcal sensors at the s-dalinac
DESCRIPTION
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 PresentationTRANSCRIPT
High Dose Irradiation of Possible FCAL Sensors at the S-DALINAC
Ch.Grah
Physics and Detector MeetingDESY HH, 29.6.2006
29.06.2006 Ch.Grah: FCAL Testbeam 2006 2
ContentsReminder of FCAL detector systems
and motivationTestbeam at the S-DALINAC of the TU
Darmstadt (12.06. -19.06.2006)•Preparations
•Some pictures from the testbeamAnalysis and first resultsSummary
29.06.2006 Ch.Grah: FCAL Testbeam 2006 3
FCAL System
LumiCal30 layer Si:W26 < θ < 155 mrad
BeamCal30 layer CVD diamond:W5 < θ < 28 mrad
Forward region of LDC (V2)
29.06.2006 Ch.Grah: FCAL Testbeam 2006 4
Sensors for FCAL
Energy deposition from beamstrahlung pairs in BeamCal.10-20 TeV and more depending on the beam parameters.
Dose of up to 10MGy/a
Investigate:• pCVD diamond sensors fromdifferent manufacturers (E6, IAF, Minsk)• Si sensors• GaAs sensors
pCVD sensor from IAF12 x 12 mm2 size, 300-500μm thickness,Ti/Pt/Au metallization
IAF: Fraunhofer Institute for Applied Solid-State PhysicsE6: De Beers Industrial Diamonds rebranded to Element Six in 2002pCVD: polycrystaline Chemical Vapour Deposition
29.06.2006 Ch.Grah: FCAL Testbeam 2006 5
Radiation Hardness of CVD diamonds
In our lab: so far only low dose irradiation
diamond response vs. absorbed dose (Sr90)
T.Behnke et al., 2001
„pCVD diamonds are radiation hard.“
29.06.2006 Ch.Grah: FCAL Testbeam 2006 6
Testbeam Purpose: High Dose Irradiation
Irradiate different sensor samples to high doses (>1 MGy). Use rather low energetic electrons similar to secondaries.
2X0 6X0 20X0
V.Drugakov
Energy spectrum of particles depositing energy in the BeamCal sensors
29.06.2006 Ch.Grah: FCAL Testbeam 2006 7
S-DALINAC of the TU Darmstadt
Using the injector line of the S-DALINAC:10 ± 0.015 MeV and beam currents from 10 to 100 nA
3 GHz electron beamenergy: 2.5 to 130 MeVintensity: 1 nA to 50 µA
Superconducting DArmstadt LInear ACcelerator
29.06.2006 Ch.Grah: FCAL Testbeam 2006 8
Accelerator Hall
29.06.2006 Ch.Grah: FCAL Testbeam 2006 9
S-DALINAC Location
CCD setup
Periodic Charge Collection Distance measurement
Remote control/surveillance of beam area
Beam Areasee next slide
Transport of sensor under HV
29.06.2006 Ch.Grah: FCAL Testbeam 2006 10
Beam Area
Monitor 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
29.06.2006 Ch.Grah: FCAL Testbeam 2006 11
G4 Simulation
Optimize distance
Optimize collimator andFaraday cup size
Reduce distance to exit window
29.06.2006 Ch.Grah: FCAL Testbeam 2006 12
G4 Simulation
Energy deposition in the sensor Spatial distribution of sensor hits
Statistics (extract R = NFC/NSensor = 0.98)
29.06.2006 Ch.Grah: FCAL Testbeam 2006 13
Sensor Holder
exit windowof beam line
collimator (IColl)
sensor box (IDia, TDia, HV)
Faraday cup (IFC, TFC)
29.06.2006 Ch.Grah: FCAL Testbeam 2006 14
Beam Area: Equipment
Power supplies and monitoring Surveillance from control room
Sensor holder
I-V conversion
29.06.2006 Ch.Grah: FCAL Testbeam 2006 15
Beam Area: Sensor (De-) Installation
29.06.2006 Ch.Grah: FCAL Testbeam 2006 16
CCD Setup Installation
29.06.2006 Ch.Grah: FCAL Testbeam 2006 17
CCD Setup Operation
typical spectrum of an E6 sensor
Sr90 source
Preamplifier
Sensor box
Trigger box
&Gate
PA
discr
discr
delay
ADC
Sr90
diamond
Scint. PM1
PM2
29.06.2006 Ch.Grah: FCAL Testbeam 2006 18
Program
•2 samples from E6•1 MGy•5 MGy
•2 samples from IAF•1 MGy•5 MGy
•2 Si samples•both drew high currentsafter ~50 kGy.
E6_4p after ~5 MGy
29.06.2006 Ch.Grah: FCAL Testbeam 2006 19
Analysis and First Preliminary Results
Tuned the beam to currents in the Faraday cup of:10, 20, 50 and 100 nA
This corresponds to dose rates of:59, 118, 296, 591 kGy/h
For now assume an error of 10%.
29.06.2006 Ch.Grah: FCAL Testbeam 2006 20
Conclusion Investigated 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.
29.06.2006 Ch.Grah: FCAL Testbeam 2006 21
The Testbeam Crew
not on the photo:W.Lange
Thanks to: INTAS and the TU Darmstadt