1. Radiation levels in CBM Radiation effects iFluka (Fluka C++ interface to CbmRoot) Fluka Geometry Models Results Conclusion

2. Radiation Damage Effects Total Ionizing Dose Displacement Damage Single Event Error hard SEE soft SEE clock data input line data in register expected data in register © T. Wijnands 2

3. MATERIALCAUSERADIATION EFFECT Semiconductors Electron-hole pairdose ionization Photon interactionphoton absorption Lattice displacement nucleon collision PolymersMain and side chain rupturedose ionization cross-linking degradation“ “ gas evolution, radical productiondose rate CeramicsLattice displacementsnucleon collision trapped charge carriersdose ionization color centers“ “ MetalsLattice displacementsnucleon collision nuclear reactions producing clusters “ “ voids and bubbles “ “ Radiation Effects – Rough Classification © Lockheed Martin 3

4. Semiconductors Polymers Ceramics Metals and alloys 1E3 1E4 1E5 1E6 1E7 1E8 1E9 1E10 1E11 1E12 1E13 rad 1E12 1E13 1E14 1E15 1E16 1E17 1E18 1E19 1E20 1E21 1E22 n/cm 2 - no damage - mild to severe damage - destruction CBM Radiation Damage to Materials/Electronics Dose & Displacement Damage 4

5. iFluka Motivations Non intrusive interface Fluka used in analogue or biased mode C++ programming using FairRoot Class Library –Generators ( Urqmd, etc... ) –Field maps definition –Standardized IO using Fairroot file structure –Parameters containers

6. iFluka Design FairRoot

7. iFluka Features Fluka version 2006.3b C++ FairRoot interface to native Fluka –Enable usage of FairRoot class library directly precise field maps info (CbmFieldMap) external generators ( CbmUrqmdGenerator etc..) etc... –FairRoot IO supported All Root IO + Stack info: (CbmMCTrack) Detector scoring info stored using CbmMCPoint General Fluka mesh normalization routine –directly linked with Fluka executable –Energy density -> Total Ionizing Dose (rad) –Fluence -> 1 MeV n-eq –etc..

8. Radiation study settings –Geometry models: CBM cave ( based on technical drawings + modifs ) Magnets ( Muon + Active ) MUCH ( compact design ) taken from CbmRoot (1%) Au target –Primary sources: DPMJET-III (delta rays + beam / beam dump ) UrQmd (Au-Au mbias collisions @ 25 AGeV) –Secondaries (transport): Delta –rays: 50 KeV, hadrons 100 KeV Low-energy neutrons library activated

9. FLUKA Geometry of the CBM Cave Field ActiveMuon Field

10. Cave Global Diagnosis ( TID) No Much MUCH

11. Cave Global Diagnosis (fluence) No MUCH MUCH

12. Global Diagnosis Xsection X=0 FluenceTID MUCH

13. MUCH induced radiation

14. Scoring planes Much scoring planes MDV+STS Scoring planes

15. Details : MVD @ z=5cm (TID) MUCH no MUCH Xsection X=0

16. Details : STS1 @ z= 30 cm (TID) MUCHno MUCH

17. Details : STS8 @ z= 100 cm (TID) MUCH no MUCH

18. Details : MVD @ z= 5 cm (Fluence) MUCH no MUCH

19. Details : STS1 @ z= 30 cm (fluence) MUCH no MUCH

20. Details : STS4 @ z= 50 cm (fluence) MUCHno MUCH

21. Details : STS8 @ z= 100 cm (fluence) MUCH no MUCH

22. Details : Much1 @ z= 130 cm (fluence) MUCHno MUCH

23. Comparisons with other MCs MVD0 (TID)MVD0 Fluence

24. Radiation studies ( CBM-Wiki) Main PageResults tables

25. Conclusion MUCH option (study with Active Field Magnet) –Impact in Tracker region ( 30 cm < Z < 100 cm ) –TID increases moderately with Z –Fluence increases x10 up to x100 with Z Soon effects due to Muon Magnet Results cross-checked with other MC´s Study of beam dump effect (PSD) beam dump design Needed : feedback from detector groups

26. BACKUPS

27. Much : Energy density

28. Much: Charged particles fluence

29. Much: neutrons particles fluence

30. Conclusion iFluka ready to be used for radiation level studies On going work: –More detailed Geometry –run time conversion to ROOT format for all Fluka estimators –Normalization routine in C++ –Comparison with TFluka (Validation) ( Collaboration with ALICE )

31. CBM radiation environment Detectors –MVD + STS –MUCH Estimators: –Energy density ( GeV/cm3/primary ) –Fluence ( 1 Mev n equivalent : n-equiv/cm2/primary)

32. Geometry

33. Scoring planes Much scoring planes MDV+STS Scoring planes

34. MVDs energy density

35. STS Energy density (1) Sts 1 Sts 2 Sts 3Sts 4

36. Sts energy density Sts energy density STS 5 STS 6 STS 7 STS 8

37. MUCH energy density MUCH 1 MUCH2 MUCH 3 MUCH 4

38. MUCH energy density MUCH 5MUCH 6

39. MVDs Charged particles fluence MVD 1MVD 2

40. STS charged particles fluence STS 1 STS 2 STS 3 STS 4

41. Sts charged particles fluence STS 5 STS 6 STS 7 STS 8

42. MUCH charged particles fluence MUCH 1 MUCH 2 MUCH 3 MUCH 4

43. Much charged particles fluence MUCH 5 MUCH 6

44. MVDs neutrons fluence MVD 1 MVD 2

45. Sts neutrons fluence STS 1 STS 2 STS 3 STS 4

46. Sts neutrons fluence STS 5 STS 6 STS 7STS 8

47. MUCH neutrons fluence MUCH 1MUCH 2 MUCH 3MUCH 4

48. MUCH neutrons fluence MUCH 5 MUCH 6

49. Conclusion iFluka used to estimate fluences for MVD, STS and MUCH Need to overlay results from UrQmd with DPM (beam dump) Need more input from detector groups Compare with real data ( TRD... ) and other MC ?

50. NIEL (1) NIEL (1) Displacement damage on Si lattice proportional to non ionizing energy transfer (NIEL) ( n, p, π+/-,e). To characterize the damage efficiency of a particle at E –Use of the normalized damage function D(E)/D(1Mev) –Tables taken from A.Vasilescu and G. Lindstroem ( http://sesam.desy.de/menbers/gunnar/Si-func.htm)http://sesam.desy.de/menbers/gunnar/Si-func.htm Normalization of hadron fluence Φ : Φ (1 MeV n-eq) = ∫ (D(E)/D(1 MeV)) Φ(E) dE with D(1 MeV) = 95 MeV mb. Φ (1 MeV n-eq) : equivalent 1 MeV-n fluence producing the same bulk damage

51. NIEL (2) NIEL (2)

52. CBM Cave Geometry ZY viewXZ view

53. The electronics cave