1. warped extra dimensions lepton signatures in ATLAS O.K. Baker Hampton University (K. McFarlane, V. Vassilakopoulos, T. Shin) SUSY05

2. gravitons in warped extra dimensions warped extra dimensions (Randall-Sundrum model PRL 83, 3370 (1999)) warped extra dimensions (Randall-Sundrum model PRL 83, 3370 (1999)) narrow graviton resonances; isolated (?) narrow graviton resonances; isolated (?) decay to SM particles decay to SM particles predictions for... predictions for... dark energy dark energy Higgless mass generation Higgless mass generation dark matter dark matter hierarchy problem hierarchy problem...... Planck braneSM (our) brane fifth dimension J. Lyyken and L. Randall

3. parameters, processes...   ~ kexp(-kr c  0 ) ~TeV warp factor   m = m n+1 - m n = kexp (-kr c  ) KK graviton mass gap q q l + l - g g l + l - G* q q l + l -  q q l + l - Z0Z0 signal backgnd mainly DY

4. studies presented here... study graviton production and decay to electrons study graviton production and decay to electrons g + g  G*  Z 0 + Z 0 g + g  G*  Z 0 + Z 0 f + f  G*  Z 0 + Z 0 f + f  G*  Z 0 + Z 0 Z 0  e - + e + Z 0  e - + e + G*  e - + e + G*  e - + e + Pythia processes 391, 392 Pythia processes 391, 392 with tuned underlying events with tuned underlying events no pileup no pileup initial LHC running period (~10 fb -1 ) initial LHC running period (~10 fb -1 )

5. ATLAS at the LHC muon systemtoroidal magnet coil inner tracking pixel, sct, trt calori- meters solenoid magnet

6. ATLAS barrel TRT ATLAS barrel TRT barrel TRT has 105,088 individual detectors; magnetic field of 2T is parallel to the beam axis. inner detector Hampton, Indiana, Duke : mechanical construction Penn, Yale : electronics barrel support structure

7. production facility on campus

8. procedure... generate pythia physics events generate pythia physics events Pythia 6.2 Pythia 6.2 perform GEANT4 simulations on.evgen files (Rome setup) perform GEANT4 simulations on.evgen files (Rome setup) perform digitization on G4 output perform digitization on G4 output perform reconstruction on digi output perform reconstruction on digi output fill ESDs fill ESDs fill AODs fill AODs analysis on AODs analysis on AODs root trees, histograms root trees, histograms i. e. full analysis chain!!

9. 500 GeV; signal and DY background signal DY background with appropriate statistics for signal and background DY cut off at 450 GeV

10. 500 GeV; signal and DY background signal DY background with appropriate statistics for signal and background DY cut off at 450 GeV

11. G*  ee 500 GeV; no background 330 events simulated  80% reconstruction

12. 500 GeV; signal and DY background signal DY

13. 500 GeV; signal and DY background signal DY

14. G*  ee (500 GeV); no background

15. analysis (700 GeV)

16. G*  ee 700 GeV; no background

17. 700 GeV; signal with DY background with appropriate statistics for signal and background

18. G* lab angular distribution; decay products angular distribution G* lab angular distribution; decay products angular distribution  electron - one electron - two G* Graviton produced with momenta along beam axis

19. Graviton decay angular distribution

20. G*  ZZ  eeee with DY background DY dielectron background with appropriate statistics for signal and background reconstruction efficiency ~50% fit to peak

21. G*  ZZ  eeee with DY background DY background

22. comparison to Tevatron data comparison to Tevatron data

23. summary have completed dielectron studies from 0.5 TeV up to 1.5 TeV have completed dielectron studies from 0.5 TeV up to 1.5 TeV have completed di-boson studies at 1.0 TeV have completed di-boson studies at 1.0 TeV have included DY and other backgrounds have included DY and other backgrounds compared to Tevatron data; can extend mass reach at LHC compared to Tevatron data; can extend mass reach at LHC can cover (model) parameter space in a few years at the LHC can cover (model) parameter space in a few years at the LHC