Year -2 topics simulations needs for these Barbara Jacak March 2, 2001

Year -2 physics topics This year’s analyses at  s = 200 –multiplicity, E T, flow –single particle spectra, ratios –HBT higher p T electron pairs and K+K- muons and e-  direct  spin

For analyses like this year HIJING events for N ch, E T,  0 corrections –~100K events adequate, as this year single particles for correction functions & embedding –as this year, but higher statistics –few days - a week CPUs usage

Charged singles corrections Throw single particles –flat in p T, weight for correct spectrum –physics processes in PISA yield decay, interaction corrections Tracking as in data –get geom. Acceptance & tracking efficiency –rely upon DC,PC simul/data agreement –correct for match, TOF cuts via cut  –TOF simulation being worked on now - will allow same cuts on MC & data Make corrections vs. p T –fit to remove statistical fluctuations Separate N ch dependence –by embedding tracks into real events –check that p T and N ch effects factorize

completeEvaluation ntuple Event Vertex: eventxvtx, eventyvtx, eventzvtx Pc Vertex: Reconstructed: pc13vtxr GEANT: pc13vtxm Bbc Vertex and t 0 : bbcvtx, bbct0 Dc charged particle track: Reconstructed: recoQual, momentumR, theta0R, phi0R, xhits, uvhits,chi2, numHitsFit Evaluation: sumfound, solution,... GEANT: momentumG, theta, phi, theta0G, phi0G, alphaG, betaG, zedG Pc1 and Pc3 hits: Reconstructed: xpc1r,ypc1r,zpc1r,xpc3r,ypc3r,zpc3r Projected: xpc1pro, ypc1pro, zpc1pro, xpc3pro, ypc3pro, zpc3pro GEANT: xpc1m, ypc1m, zpc1m, pc3mcid, xpc3m, ypc3m, zpc3m

Particle generation, decay vertex, ID: generation, particleID, parentID, primaryID, rvtx, zvtx Emc shower position and energy: Reconstruced: xemcreco, yemcreco, zemcreco, emcecore, emcecorr,... Projected: xemcproj,yemcproj,zemcproj,pathlemc GEANT: xemcmc,yemcmc,zemcmc,.. Crk PMTs/pathlength: Reconstructed: crkacc, crknpmt0, crknpmt1, crknpmt3, crknpe0, crknpe1, crknpe3, crkchi2, crkdisp Projected: crkpath Tof time-of-flight: Reconstructed: xtofr, ytofr, ztofr, toftofr, elosstofr, pidtofr Projected: xtofpro, ytofpro, ztofpro, tofpath GEANT: xtofm, ytofm, ztofm, toftofm,elosstofm, pidtofm completeEvaluation ntuple...

Pairs Factorize corrections Throw single parent distribution –according to physical distribution –events have 2 instead of 1 particle corrections as for singles Denominator in corrections –daughters within acceptance & kinematic cuts –separate correction for this analytical for resonances with known decay kinematics cannot do w/o model dependence for continuum impose geometry/kinematic cuts on theory Relation to singles corrections –2D space, fit function to corrections –exchange systematic  for statistics

HBT Single particle corrections cancel MC corrections for 2-particle acceptance, efficiency cutting into q space MC to study residual correlation effects

Higher p T needs Full simulation of TEC tracking –tune as was done for DC Modeling to optimize outer detector cuts –further response tuning? Single particle events with full history –develop cleanup for p T >5 GeV/c –recall S/B now ~1 at 5 GeV/c Separate check of multiplicity dependence

Direct photons Calorimeter analysis –understand showers to few % –embed showers/high statistics –systematic studies specialized simulations by the analyzers themselves requires CPU availability Via conversions –special runs in both data and MC magnetic field extra converter –systematics on e ID, kinematic cuts described already by Akiba Some full HIJING events for background study

Summary Few 100K central arm full HIJING events –also need muon full events… –but muon embedding important! Many single particle runs –centralize generation & reco? –Common embedding study? Pair acceptance studies Resources for systematic studies –by analyzers themselves