1. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 1 Radiation Testing at KSU for the Run 2B Upgrade  L0/L1/L2 sensors from both HPK and ELMA tested with 7-14 MeV proton beams at the James R. Macdonald Laboratory, a DOE national user facility for accelerator-related AMO physics.  Many other detector components tested as well (hybrids, epoxy, cables, …).

2. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 2 Basic Setup  Beam from 7 MV tandem Van de Graaff (mostly 10 MeV protons).  Basic setup: u Samples are mounted in a vacuum target chamber un- powered. u Beam is rastered over sample using sawtooth pattern electric fields. u Current measured by Faraday cup/current integrator to 10 pC least count. u Runs are for fixed amount of charge, with beam currents 10-100 nA. u Sensors are annealed for 80 minutes at 60C, then electrically tested. u Multiple fluence points are taken on single sensor. u Long term storage is at -20C.

3. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 3 Layout

4. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 4 Fluence Checks  Fluence = integrated flux.  In L2 PRR, some issues arose over value of damage coefficient  (I Leak /volume =  ), which appeared ~3×too low when  was re-expressed in terms of 1 MeV neutron equivalent fluence assuming standard NIEL scaling arguments.  Issue now resolved. Simple plotting error (corrected) and unaccounted for physics effect: 10 MeV protons do not obey NIEL scaling.  Nevertheless motivated several checks of fluence.  See more extended write-ups in your “book” for details.

5. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 5 Current Integration Tests  Faraday cup is close behind target.  Only beam passing through sample in Al window is counted.  Efficiency corrections of ~1.01/1.02/1.1 for L0/L1/L2 are applied for MCS.  Efficiency checked to ~10% in special runs  largest flux uncertainty.  Faraday cup cross-checked with other cup; current measurements checked against independent pico-ammeters to < 1%.

6. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 6 Copper Activation Analyses  1.5 mil natural copper foils irradiated in same beam with protons to produce Zn-63(  1/2 =38 min.) and Zn-65 (  1/2 =244 days), which  + or EC decay with accompanying  ’s.  Zn-63 rates and Zn-65 rates measured at KSU Nuclear Reactor Lab using Ge well counter with NIST calibrated sources for efficiency and standard industry software  inferred fluence agrees with direct measurement to 10%.  Zn-65 rate measured independently with NaI(Tl) counter by KSU AMO physicist  same level of agreement.  Zn-65 samples measured independently at FNAL ES&H facility using Ge disk counter  18% agreement with KSU.  Main uncertainty in activation analysis is Cu(p,n)Zn cross section (~10%), but many details need to be sorted out.  FNAL/KSU discrepancy not fully resolved, was converging.

7. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 7 Activation Summary  Activation analyses are consistent with direct fluence measurements.  No reason not to use more precise values from beam system.

8. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 8 Comparison with other proton data  We discovered belatedly that the best way to present our data is directly in terms of integrated proton fluence, rather than converting to 1 MeV neutron equivalence using the NIEL scaling hypothesis.  In doing this, we can compare directly with measurements taken with a similar setup at Montreal (RD48/ROSE Collaboration, D. Bechevet et al), Nucl. Instrum. Meth. A479: 487- 497,2002).  NIEL scaling fails in this regime: this is well known to several members of this committee.  Our data is consistent with an  P value that is approximately independent of sensor type and geometry and which agrees with that measured by RD48/ROSE at both 10 MeV and 7 MeV.

9. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 9 10 MeV Leakage Current Summary

10. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 10 7 MeV Leakage Current Summary

11. Tim Bolton, KSU Run 2B L0/L1 PRR Aug 7, 2003 11 Conclusions  We can reliably use proton beams from the KSU Macdonald Lab for radiation testing of all sensor types. u Beam current measurements are internally self-consistent. u Beam current and activation measurements are consistent. u Leakage current measurements agree with CERN results.  Our L1 data includes fluence to 10 14 protons/cm 2, well beyond anticipated Run 2 exposure.  We are beginning to irradiate production L2 test structures for QC/QA purposes.