03/27/'07T. ISGC20071 Computing GRID for ALICE in Japan Hiroshima University Takuma Horaguchi for the ALICE Collaboration 03/27/’07 for ISGC2007

03/27/'07T. ISGC20072 Outline Introduction LHC ALICE Experiment ALICE Offline Analysis –Simulation data –Data Flow Computing Hiroshima University Current Status as a User Summary

03/27/'07T. ISGC20073 Introduction Our purpose for using Grid Computing –Data analysis for the ALICE LHC for the study of the Quark-Gluon Plasma (QGP) Our Goal for the Grid Computing –Join the Grid as a Tier2 and provide the CPU power for the ALICE Experiment (without a break !) I will report the status of the computing Hiroshima University in this presentation !

03/27/'07T. ISGC20074 Large Hadron Collider (LHC) p+p collisions –14TeV Pb+Pb collisions –5.5TeV/A The collision energy of LHC is much more than RHIC (0.2TeV/A) ! Circumference length –27km The p+p collisions at 900GeV will be started from this November !

03/27/'07T. ISGC20075 ALICE Experiment ALICE –A Large Ion Collision Experiment Experiment for the Heavy Ion –Quark matter will be produced, which is High temperature High density Long life time –Study of Quark-Gluon Plasma (QGP) PHOS

03/27/'07T. ISGC20076 ALICE Collaboration 30 Countries, 96 Institutions, 1015 Members (in January, 2007)

03/27/'07T. ISGC20077 Photon ALICE –p+p collisions Hadron decay Prompt photon –Comparison with pQCD calculation –Gluon distribution function Reference data for the heavy ion collisions –Pb+Pb collisions Hadron decay Prompt photon –Jet Quenching Thermal Photon

03/27/'07T. ISGC20078 Photon Spectrometer (PHOS) Photon Spectrometer –ElectroMagnetic Calorimeter –PbGO 4 Crystal –APD readout –5 moudules 64×56 (1 moudule) The installation will be started from this end of May ! (1 module)

03/27/'07T. ISGC20079 ALICE Offline Analysis Simulation Data （ December 2006 ） –pp 900GeV PYTHIA (Event Generator) Minimum Bias 200K event –pp 14TeV PYTHIA (Event Generator) Minimum Bias 20M event –Pb+Pb 5.5TeV will be generated near future PYTHIA+GEANT+Reconstruction –Event Summary Data (ESD) –Analysis Object Data (AOD) ALICE Grid (March 2007) –About 8000 node –Average availability : 46% –More than 2000 jobs are submitted in a day. –For Pb+Pb collisions, we need about node !

03/27/'07T. ISGC ALICE Offline Analysis Date Flow in ALICE DAQ T0 T0 Buffer CAFT1 ESD T2 ESD AOD On line Analysis First Reco 2-3 Reco User Analysis Offline Analysis

03/27/'07T. ISGC Computing Hiroshima For a User University just have been able to submit their jobs ! For a Host –Machines just have been installed this middle of March ! –CPU 38×2 (Intel Xeon 5160) 3GHz –Storage 42TByte –The machine power will increase in a few years ! –Plan Install Grid Middleware Setup ALICE analysis framework This work will be started from this April (after the ISGC2007 !)

03/27/'07T. ISGC GRID Computing

03/27/'07T. ISGC GRID Computing

03/27/'07T. ISGC Current Status as a user Pi0 mass distribution –p+p 14TeV simulation data PYTHIA+GEANT+Reconst ruction 60K event analysis was finished. More detail analysis is processing with Computing Grid now ! pp minimum 14TeV Pi0 mass peak

03/27/'07T. ISGC Summary ALICE Experiment –The highest energy heavy ion collisions experiment with LHC –The p+p collisions at sqrt(s)=900GeV will be started from this November ! Photon Physics in Heavy Ion Collisions –Photon Spectrometer Installation of the Hiroshima University –The installation just have been finished in this middle of March –The installation of the Grid Middle ware & ALICE analysis framework will be started from this April. Analysis for the ALICE simulation data with Grid –We just obtained the pi0 mass distribution of the simulation data with Grid. –More detail analysis is processing at Hiroshima University with Grid Computing !

03/27/'07T. ISGC First pp run conditions √s (TeV)0.9 L (cm -2 s -1 ) 2    t (s) (2 days) (10 days) 1 PHOS module  = 0.24 × 20°   = 0.9 (assuming there is NO material in front of PHOS!) A  (p t ) p t < 10 GeV/c 10 GeV/c < p t < 100 GeV/c (p 0 + p 1 p t )(1- e -(pt- p 2 )/ p 3 ) ) p 0 = p 1 = c/GeV p 2 = 0.55 GeV/ p 3 =1.25 GeV/c p 0 = p 1 = c/GeV p 2 = 14 GeV/ p 3 =12 GeV/c