SoLID Simulation

1. SoLID Simulation Zhiwen Zhao 赵志文 University of Virginia Third Workshop on Hadron Physics in China and Opportunities in US 2011/8/9 • Introduction • Simulation framework • Simulation study

2. SoLID-Solenoidal Large Intensity Device • One of three major new equipments of Hall A 12GeV upgrade besides Super Bigbite (SBS) and Moller • General purpose device. • Physics approved proposals: • PVDIS (XiaochaoZheng’s talk) • SIDIS (XinQian’s talk) Submitted proposals: • b1, deuteron tensor structure function • proton transversity Proposals in preparation: • g3z, parity violating spin structure function • PVRES, parity violation in resonance region

3. ComgeantThe Past • Geant3 based simulation program. • geometry/sensitivity/digitization/field as input files and detached from main code, run different settings without recompilation. • Successfully used for PVDIS and SIDIS proposals.

4. GEMC (GEant4 MonteCarlo)The Present and Future http://gemc.jlab.org https://hallaweb.jlab.org/wiki/index.php/Solid_sim_geant4 • C++ program that simulates particles through matter using the Geant4. • Successfully used for CLAS12. • Detector information are stored in mysql database. configuration changes are immediately available to users without need of recompiling the code. • Hit process factory: associate detectors with external digitization routines at run time. • perl script I/O to database, no need to know C++ or Geant4 to build detector and run the simulation. GEOMETRY, BANKS, DIGITIZATION DATABASE gemc network

5. GEMC interface Batch mode

6. Detector GEMC interface Interactive mode Run Control Camera

7. SIDIS with BaBar Magnet Magnet/coil/yoke

8. SIDIS with BaBar Magnet Target/Beam line

9. SIDIS with BaBar Magnet GEM

10. SIDIS with BaBar Magnet EC, large angle

11. SIDIS with BaBar Magnet Collimator

12. SIDIS with BaBar Magnet Cherenkov, light gas

13. SIDIS with BaBar Magnet Scintillator

14. SIDIS with BaBar Magnet Cherenkov, heavy gas

15. SIDIS with BaBar Magnet MRPC (Multigap Resistive Plate Chambers)

16. SIDIS with BaBar Magnet EC, forward angle

17. SIDIS with BaBar Magnet 2DGeant3 3DGeant4

18. SIDIS with BaBar Magnet 2DGeant3 3DGeant4

19. PVDIS with BaBar Magnet 2DGeant3 3DGeant4 Baffle

20. PVDIS with BaBar Magnet 2DGeant3 3DGeant4 Baffle

21. SoLID GEMC Framework • geometry/sensitivity/digitization/field in mysql database. • Customized hit processing for various detectors. • Unified individual detector simulation and the whole SoLID simulation. • GEMC can be used for other projects.

22. Simulation Study • Magnet Option • SIDIS Kinematics Study • PVDIS baffle design and FOM • Background rate and GEM tracking • Energy flux and EC • Cherenkov • Neutron background • Other progress

23. Poisson 2D Magnet Option BaBar CDF CLEO ZEUS

24. Magnet Comparison Paul E. Reimer

25. SIDIS Kinematic Coverage@11GeV BaBar • Green area, • large angle coverage • Black area, forward angle coverage

26. SIDIS Kinematic Coverage@11GeV

27. PVDIS Baffle BaBar Reduce background by 50

28. PVDIS FOM

29. Background Rate on GEM for SIDIS BaBar CDF Condition: 15uA 11GeV e- beam, 40cm 3He 10amg gas target Todo: more realistic GEM module description in progress, borrowed from SBS simulation.

30. Tracking Progressive Method (curved tracks) 3/4 3/4 PVDIS, based on simulated background on GEM No EC • Add EC, with BG Single/Multi : 97.5/0.27% time: 100 s

31. Energy Flux Rate on ECfor SIDIS with BaBar Magnet BaBar 60krad/y Forward angle Large angle Condition: 15uA 11GeV e- beam, 40cm 3He 10amg gas target Todo: more careful study of hadron energy flux in progress

32. IHEP 2010 module EC (Shashlik) • Dimensions 38.2x38.2 mm2 • Radiation length 17.5mm • Moliere radius 36mm • Radiation thickness 22.5 X0 • Scintillator thickness 1.5mm • Lead thickness 0.8mm • Radiation hardness 500 krad • Energy resolution 6.5%/√E 1%

33. EC (Shashlik) transverse sizeRough numbers only w/ 50ns ADC gate block Size (cm)

34. SIDISCherenkov: Optics One spherical mirror

35. SIDISCherenkov: Detector • (Some) Requirements: 1) resistant in magnetic field • 3) decent size • 2) “quiet” yes yes ? Used by PHENIX successfully Gaseous Electron Multiplier + CsI • GEMs + CsI: resistant in magnetic field, size is not a problem • Consists of 3 layers of GEMs, first coated with CsI which acts as a photocathode • First GEM metallic surface overlayed with Ni and Au to ensure stability of CsI (CsI not stable on Cu) The simulation shows good collection efficiency.

36. SIDIS L.-G. Cherenkov: Photon Detector • (Some) Requirements: 1) resistant in magnetic field • 3) decent size • 2) “quiet” possibly good enough yes if tiled ? ? ? Photomultiplier Tubes • Multi-anode 2” PMT: fairly resistant in magnetic field; it can be tiled (data from Hamamatsu) 1.93” effective area (94%) Square shaped and 94% effective area: ideal for tiling 2.05” Initial test shows we can safely run at less than 70G The simulation gives us the guidance of local magenetic field where the PMT is located.

37. Neutron Background Damage function FLUKA Shielding: Polyethylene

38. Neutron Background Shielding reduces neutron flux in half at two test locations

39. Other Progress • GEM A small prototype was tested at Jlab. Combined Efforts from UVa/INFN/Jlab/China are in coincidence with GEM R&D for the SuperBigbite & EIC. Several large prototypes are being built in US and China. • MRPC Chinese collaborators will come onsite for beam test later this year. • DAQ Collaborating with Hall D.

40. Summary • SoLID collaboration has successfully adopted GEMC as its Geant4 simulation framework and joined in GEMC development. The simulation is ready to be used for various studies to help detector design. • A lot of subsystem design and simulation progresses have been made. More studies are under way. • In preparation for the director review.

41. Thanks • Maurizio Ungaro (GEMC) • Paul Reimer (Magnet, Calorimeter) • Seamus Riordan (Baffle, PVDIS FOM) • Lorenzo Zana (Neutron BG) • SimonaMalace, Eric Fuchey, Yi Qiang (Cherenkov) • Jin Huang, MehdiMeziane (Calorimeter) • Yang Zhang (SIDIS kinematics) • Eugene Chudakov (Comgeant PVDIS, Baffle) • XinQian (Comgeant SIDIS, tracking) • SoLID Collaboration

42. Backup

43. How To: new detector, hits $detector{"pos"} = ”10*cm 20*cm 305*mm"; $detector{"rotation"} = "90*deg 25*deg 0*deg"; $detector{"color"} = "66bbff"; $detector{"type"} = "Trd"; $detector{"dimensions"} = ”1*cm 2*cm 3*cm 4*cm 5*cm"; $detector{"material"} = "Scintillator"; $detector{"mfield"} = "no"; $detector{"ncopy"} = 12; $detector{"pMany"} = 1; $detector{"exist"} = 1; $detector{"visible"} = 1; $detector{"style"} = 1; $detector{"sensitivity"} = "CTOF"; $detector{"hit_type"} = "CTOF"; $detector{"identifiers"} = "paddle manual 2"; 16th: Bank 17th: Digitization Routine In general, 1 bank  1 digitization routine… but not necessary

44. Factory Method for Hit Processes Hit Process, Digitizations External Routines SVT CTOF • Automatic Process • Routines Still External • Easy to: • add new routine • debug • modify gemc DC gemc FTOF

45. Digitization Available For every G4 step Hit Process Example • Hit Position • Volume Local Hit Position • Deposited energy • Time of the hit • Momentum of the Track • Energy of the track • Primary Vertex of track • Particle ID • Identifier • Mother Particle ID • Mother Vertex Average (x,y,z) Average (lx, ly, lz) Total E Average t Average p (final p) Energy Primary Vertex of track Particle ID Strip, Layer, Sector

46. Event Generation Particle gun built in, two luminosity beams can be added LUND Format (txt) for physics events Data Output evio, bank alike binary format by Jlab DAQ group Root tree, convert from evio text

47. SoLID Event Generator • DIS e- and pion generators are ready in C++ • e- and pion coincidence generator is ready in C++ • FLUX, raw, EC … SoLID Hit Processing

48. SoLID Simulation Databasresoliddb.jlab.org • Mysql 5 cluster server. It is highly efficient and has minimum downtime. • Flexible development structure.

49. Documentation • gemc.jlab.org • https://hallaweb.jlab.org/wiki/index.php/Solid_sim_geant4

50. Netpbm