LHC时代的宇宙线实验研究.ppt

Cosmic Ray Experiments in the Era of LHC Zhen Cao Institute of High Energy Physics, Beijing, China TEXAS2010, Heidelberg, Germany, Dec.2010 Outline Questions in cosmic ray measurements Impacts from the new results on colliders High Precision Era: Electron spectra Antimatter spectra Cosmic ray spectra using calorimeters (E100TeV) High statistics Era: Anisotropy at different scales (E100TeV) CR composition: Still challenging but hopeful with LHC Multi-parameter particle identification technique Energy scale for ground based experiments High altitude multi-parameter measurement complex array in near future Summary Where are the knee, the second, the ankle ? E-scaleWhat happen around them? Composition Why do they happen? Acceleration/propagation effect Entangled problems Big uncertainties in modeling of shower development Lack of experimental data nailing down parameters in the models Unknown composition No way to carry out absolute calibration because test beams are not energetic enough and impossible for ground array p-p cross section by SPS, Tevatron and LHC will put great constraints on σp-air(E) Phys. Rev. D 80 (2009) 092004  QCD does not help for small momentum transfer Secondary particle momentum distribution is far to be well measured: the last well done job was before 1984 on ISR at 23 to 62 GeV Models go with P238 As a consequence, e.g. the composition of CRs After being discovered 50 years we are still debating about where is the knee, is it sharply or gradually bent KASCADE had put hadronic calorimeter+AS+MUON together, it turned out more entropy rather than sorting out anything better We are looking for 7TeV and 14TeV results, eagerly.There will be a great opportunity to disentangle the long standing problems. PAMELA Yangbajing Valley  CR/γ Observatory ARGO-YBJ Experiment High Precision EraCosmic Ray Spectrum Measurements- calibrated calorimeter at test beams  - multi-parameter particle identification technique