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Ozgur Ates Hampton University. TREK Experiment “Tracking and Baseline Design” And OLYMPUS Experiment “Study of Systematics”. 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.
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Ozgur AtesHampton University TREK Experiment“Tracking and Baseline Design” And OLYMPUS Experiment “Study of Systematics”
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
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
Planar GEMs“C1”between CsI and C2, or in replacement of C2 • Cylindrical device “C0” • in replacement of C1
C1: Planar GEMs for TREK • “C1”To cover CsI gaps on the outside
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
Geant4 Simulation • 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
Geant4 Simulation • Got started with • Geometry of Sci. target + 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
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
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)
OLYMPUS Exp.: The contribution of multiple photon exchange in elastic lepton-nucleon scattering • Study of Elastic Scattering of Electrons and Positrons • Luminosity Monitors • Systematic Study of Resolutions • Monte Carlo Studies and Root Analysis
Proton Form Factor Ratio Jefferson Lab • All Rosenbluth data from SLAC and Jlab in agreement • Dramatic discrepancy between Rosenbluth and recoil polarization technique • Multi-photon exchange considered best candidate Dramatic discrepancy!
Luminosity Monitors: Telescopes Proposed version included in OLYMPUS TDR Sept. 2009 2 tGEM telescopes, 1.2msr, 12o, R=187/237/287cm, dR=50cm, 3 tracking planes Forward telescopes 12o TOF • Geant4 simulation to optimize vertex resolution, solid angle and noise
Triple Super Ratio Ratio of luminosities Ratio of acceptances (phase space integrals) Ratio of counts • Separately determine three super ratios • Blinding of final result until put together • Left-right symmetry = redundancy
Forward Elastic Luminosity Monitor • Forward-angle electron/positron telescopes with good angular and vertex resolution • Coincidence with proton in opposite sector of main detector • Single-arm tracks • Two telescopes with 3 triple-GEM detectors, left-right symmetric • High rate capability • GEM technology MIT protoype: Telescope of 3 Triple GEM prototypes (10 x 10 cm2) using TechEtch foils F. Simon et al., NIM A598 (2009) 432
Study of Elastic Scattering • FOUR VECTORS: • e=(E,Pe) E^2= (me^2) + (Pe^2) • e’=(E’,Pe’) E’=|Pe’| and E=|Pe| • p=(M,0), E=2 GeV and M=0.938 GeV • p’=(Ep,Pp) • CONSERVATION LAWS: Energy: E – E’ = Ep – M Transverse : E’ Sin(Te)=Pp Sin(Tp) Longitudinal: E – E’Cos(Te)=Pp Cos(Tp) *** Ep^2= Pp^2+M^2
Study of Elastic Scattering • We have 4 variables: Pe, Pp, Te, Tp • 3 constraints: 3 conservation equations • 4 - 3= 1 (DEGREE OF FREEDOM) • Then I can find out 12 Different Relations: • Pp(Tp) inverse Tp(Pp) • Pe(Te) inverse Te(Pe) • Pp(Te) inverse Te(Pp) • Tp(Te) inverse Te(Tp) • Pp(Pe) inverse Pe(Pp) • Tp(Pe) inverse Pe(Tp)
Study of Resolutions • For Proton Left Sector: • Vertex Resolution in Z axis: 0.8 mm • Polar Angle Resolution (Theta): 0.09 Degree • Azimuthal Angle Resolution(Phi): 0.14 Degree • Momentum Resolution: 36 MeV • For Electron Left Sector: • Vertex Resolutions in Z axis: 0.6 mm • Polar Angle Resolutions (Theta): 0.08 D • Azimuthal Angle Resolution(Phi): 0.10 Degree • Momentum Resolution: 36 MeV
What is Next? Montecarlo Studies • Study of Systematics • Further (small) corrections for individual acceptances • Effects by backgrounds and inefficiencies • Effects from beam sizes, slopes and offsets • Construction of GEM LAB@HU!!!!!