Ozgur Ates Hampton University HUGS 2009-JLAB

1. Ozgur AtesHampton UniversityHUGS 2009-JLAB TREK Experiment“Tracking and Baseline Design”

2. The Hadron Hall at J-PARC Secondary lines for +, K+, or p beam Secondary lines for -, K-, or p beam 50 GeV/c proton beam to primary production target

3. Time Reversal violation Experiment with Kaons: Search for New Physics beyond the Standard Model by Measurement of T-violating Transverse Muon Polarization in K+ μ+π0 νμ Decays New official website: http://trek.kek.jp

4. Planar GEMs“C1”between CsI and C2, or in replacement of C2 • Cylindrical device “C0” • in replacement of C1

5. C1: Planar GEMs for TREK • “C1”To cover CsI gaps on the outside

6. Target andTracking • Addition of C0 and C1 • GEM chambers with • -high position resolution • - higher rateperformance • Larger C3-C4 • distance • Use of He bags E246 J-PARC • Better kinematical resolution • New target

7. Upgraded Trek Detector Apparatus

9. Geant4 Simulation • Geant4 studies initiated in Summer 2008 • GOALS: • Realistic geometry of upgraded TREK apparatus • Realistic tracking performance Obtain design criteria for • Sizes and locations of new elements • Angular and spatial resolution of tracks at detector elements • Which spatial detector resolution is adequate? • Optimization of material budget

10. Geant4 Simulation • Got started with • Geometry of target (from Steffen/Eric) + C0 + C1 + C2, coded materials • Full cylinders of target and C0 but only one of 12 sectors for C1,C2 • Generate monoenergetic 100 MeV muonsuniformly distributed over volume of targetwithopening angle according to muon gap size. • Produce hits in detector elements of C0, C1, C2 • Use multiple scattering or physics off • Record hits along track and write set of variables (th, ph, z, y, p, edep. mom, etc.) to ROOT TREE

13. Root Analyses • Studied acceptance of tracks in C0, C1, C2. • From this study,determined required geometric sizes of C0 and C1. • Found out that; • Length of C0 should be: 300 mm • Width of C1 should be: 200 mm • Length of C1 should be: 480 mm

14. Determination of Length of C0

16. Determination of Width of C1

17. Determination of Length of C1

18. Straight-Line Fit in 3D • Recorded hit locations of Readout layers of C0, C1 and C2. • Appliedstraight-line fit in 3D for each generated event. • Reconstruct straight track from recorded hits with 3D straight-line fit • Recorded fit parameters for each track, and locations of fitted trackat each 3 readout layers. • Closest distance of reconstructed track to origin of generated track (vertex difference)(1st column) • Difference of generated hit position at detectors(C0,C1,C2) and that of the recons. track (2nd to 4th column)

19. RESIDUALS

20. Systematic Study of Resolution

22. Backup Slides • Sanity check: Residuals for Phys=OFF and perfect detectors • Intrinsic tracking resolution: Explicit Gaussian smearing of hits • Study effect of physics (MS, Bremss., Ionization, Pairprod. ) separately fromintrinsic resolution, use balancing as criterion for design resolution • studied residuals, i.e. difference of generated and reconstructed hit locations at each readout layer, and at target vertex (closest point with respect to generated vertex) • studied residuals with and without physics activated in Geant4 (multiple scattering and energy loss) • concluded lower limits the required intrinsic resolution (<<residual)

23. High Rate Chamber – Gas Electron Multiplier (GEM) • Still Gas Ionization and Avalanche, again, but… • A different way to get an intense electric field, • Without dealing with fragile tiny wires, and • Release + ions much faster -V GEM ~400v 0.002” http://gdd.web.cern.ch/GDD/ To computer