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First results on particle correlations from ALICE. Dariusz Mi ś kowiec, GSI Darmstadt and EMMI for the ALICE Collaboration . why two-pion correlations two-pion correlations at 900 GeV first look at 7 TeV data try harder: high-p T correlations summary.
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Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 First results on particle correlations from ALICE Dariusz Miśkowiec, GSI Darmstadt and EMMI for the ALICE Collaboration why two-pion correlations two-pion correlations at 900 GeV first look at 7 TeV data try harder: high-pT correlations summary
Collectivity in nuclear collisions Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 collective transverse velocity apparent source of pions with given (y,pT) transverse expansion pT spectra look thermal but boosted longitudinal expansion source size depends on pT 2 2
Transverse expansion Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Mike Lisa, CERN Theory Phenomenology Seminar, 16-Oct-2009 temperature and transverse flow when energy conservation treated properly transverse expansion seems to be there even in very peripheral nuclear collisions 3 3
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Pion source size from STAR STAR, arXiv:1004.0925 [nucl-ex] STAR, Phys. Rev. C 80 (2009) 24905 p + p (various ways of fitting) Au + Au Cu + Cu pT dependence of pion source size similar in nuclear and pp collisions
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 identical-pion correlation analysis technique (HBT) peak width ~ 1 / source size pion source size accessible experimentally
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Two-pion correlation functions in A+A and p+p collisions baseline shape is the challenge in p+p data
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 pp at sqrt(s) = 900 GeV 250 k minimum bias events 10 days starting on Dec 6, 2009 7 7
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 identical pion correlation functions Bose-Einstein peak clearly visible D. Miskowiec, ALICE femto meeting 2010-03-22 8 8
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Unlike-sign pion correlation function Coulomb and K0S peaks visible D. Miskowiec, ALICE femto meeting 2010-03-22 9 9
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Multiplicity and transverse momentum dependence identical pions unlike-sign pions baseline has to be treated properly
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Multiplicity dependence for comp.: nuclear collisions M. Lisa, Ann. Rev. Nucl. Part. Sci. 55, 357 visible dependence in pp HBT radii depend on multiplicity rather than on collision geometry
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Transverse momentum dependence no significant dependence on transverse momentum for comparison: in nuclear collisions
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Dependence on the baseline assumption but: transverse momentum dependence is sensitive to the baseline shape assumption
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 pp at sqrt(s) = 7 TeV 180 M minimum bias events from March 31 till now 120 M events used for this talk
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 pp at sqrt(s) = 900 GeV 7 M minbias events on May 2-3, 2010 2.1 M events used for this talk
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 7 TeV and new 900 GeV data identical pion correlations 120 M events at 7 TeV 2.1 M events at 0.9 TeV high-q baseline flatter at 7 TeV
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 π+π-correlations at 7 TeV Coulomb K0S rich resonance structure ω ρ f0 f2 low-q baseline steeper at 7 TeV origin: jets high-q baseline flatter at 7 TeV origin: momentum cons.
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Non-identical particle correlations from pp at 7 TeV pion - kaon C(qout ) asymmetry -- another handle on transverse flow K* example: Pb+Au at 17.2 GeV CF’s from CERES π+π -π- p π+p pion - proton Λ Δ
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 Summary HBT radii at 900 GeV depend on multiplicity no strong dependence on transverse momentum correlation baseline of crucial importance
transverse momentum dependence of Rside Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 21 21
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 baseline slope significant at 0.9 TeV and above study by Adam Kisiel 22 22
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 7 TeV, identical pions low mult high mult
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 High stat 900 GeV from 2010, identical pions low mult high mult
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 7 TeV, unlike-sign pions low mult high mult
Dariusz Miskowiec, Particle correlations in ALICE, Physics at the LHC, Hamburg, 10-Jun-2010 High stat 900 GeV, from 2010 unlike-sign pions low mult high mult