DOE ILC The International Linear Collider Project SIMULATION

DOE ILC – The International Linear Collider Project SIMULATION OF BEAMCAL WITH B FIELDS Shirley Choi, Keith Drake, Christopher Geraci, Joshua Elliot, Jack Gill, Jason Gray, Kyle Miller, Sarah Moll, Gleb Oleinik, Uriel Nauenberg, Joseph Proulx, Elliot Smith, Paul Steinbrecher, Jiaxin Yu Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project 2 Photon Process e+ Very forward into BEAMCA e+ γ - q, l in the detector γ q, l Very forward into BEAMCAL ee. Discussion in Beam Cal section at end Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project The FCAL Collaboration BNL Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Lumi Cal -7 mrad ent. 7 mrad exit Beam Cal at z=295 cms Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Study the efficiency to observe the electron and positron of the two photon process above the beamstrahlung background Essential to remove this background in the study of Supersymmetry in the dynamical region of low Pt. Needed to measure the masses. Work by Paul Steinbrecher and Gleb Oleinik Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Testing GEANT 4. 0 Evidence for multiple scattering Muons directed at 7 mrad air in beam pipe No field, 50 Me. Vmuons No field, 50 Ge. V muons Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project 50 Me. V, no field, forward 50 Me. V, solenoid on, forward Solenoid field shrinks effect of mult. scattering Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Solenoid field keeps the low energy charged particle in the forward direction. Beam hole is at 7 mrad. Need to add an x field component to move low energy charged particles in the 7 mrad direction. Anti-Di. D dipole field proposed by Andrei Seryi. Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Beamstrahlung Distribution with Solenoid + Anti-Di. D No beam pipes Beam pipes Entrance Exit Difficult region to detect 2 photon process Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project GEANT 4. 0 seems to be working properly We have fixed various bugs in collaboration with SLAC team. According to Seryi Anti-Di. D was tuned assuming BEAM CAL is at L* ~ 350 cm. BEAM CAL for Si. D is at 295 cm. Effect is clearly seen. Need to retune Anti-Di. D to larger values. We are doing this. All Simulation is work in progress. Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Final Aim We want to determine how far down in Pt we can observe the two photon background by requiring that we observe the forward electron and positron above the beamstrahlung. We will use the standard that we can not observe the signal if the beamstrahlung energy deposited in 1 x 1 cm 2 is 3 (0. 75 Te. V) times the beam energy (0. 25 Te. V). Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project The ILC Parameters Committee is asking us to evaluate how well one can observe the process ~ ~ e+ e- →τ+ τ - →χ~10 τ+ χ~01 τ where the stau-neutralino mass difference is 5 Ge. V. This is roughly point 3 in the Snowmass 2001 parameter set. Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Univ. of Colorado, Boulder, Sept. 2006

DOE ILC – The International Linear Collider Project Univ. of Colorado, Boulder, Sept. 2006