1. iFluka : a C++ interface between Fairroot and Fluka Motivations Design The CBM case: –Geometry implementation –Settings for radiation studies –Global diagnosis Conclusion and Outlook

2. 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

3. Design FairRoot

4. 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 –Fluences -> Dose –Fluence -> 1 MeV n-eq –etc..

5. Radiation study settings –Geometry: CBM cave ( based on technical drawings + modifs ) Magnet + (1% ) target + MUCH ( compact design ) taken from CbmRoot –Primary sources: DPMJET-III (delta rays + beam / beam dump ) UrQmd (Au-Au central collisions ) –Secondaries (transport): Delta –rays: 50 KeV, hadrons 100 KeV Low-energy neutrons library activated –Magnetic field map from CbmRoot –1 Mev n-equivalent fluence normalization

6. New Geometry of the CBM Cave

7. CBM Detectors (1)

8. CBM Detectors (2)

9. CBM Cave Geometry ZY viewXZ view

10. 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

11. NIEL (2) NIEL (2)

12. Cave charged particles fluence DPM UrQmd

13. Cave neutrons fluence DPM UrQmd

14. The electronics cave

15. Much : Energy density

16. Much: Charged particles fluence

17. Much: neutrons particles fluence

18. 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 )