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Michel GONIN. Lecture 2 on J/ ï¹ suppression. 1. Charmonium bound states. 2. Screening effects in the plasma. 3. Experimental results. 4. Life (for physicist) is tough. l D depends on the temperature. ï³. quarkonia. q. q. Lattice QCD. ï¹ â€™. ï¹. T > T c. ï‚¡. ï³ = 0.
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Michel GONIN Lecture 2 on J/ suppression 1. Charmonium bound states 2. Screening effects in the plasma 3. Experimental results 4. Life (for physicist) is tough
quarkonia q q Lattice QCD ’ T > Tc = 0 Signals for the Deconfinement Successive (vs. temperature) melting for the quarkonia Satz et al.
Screening Temperature Energy density(GeV/fm3)ε Suppression Bounding Energy (MeV) ψ χ ’ ψ’ Quakonia Screening 1 2 3 4 5 ε Satz et al.
NA50 at CERN Electromagnetic desintegration c c
How does PHENIX see the J/ ? J/ e+e– identified in RICH and EMCal • || < 0.35 • p > 0.2 GeV J/μ+μ– identified in 2 fwd spectrometers • 1.2 < || < 2.4 • p > 2 GeV
Cathode-strip chambers = 24000 voies analogiques / bras • Pistes = 1cm s (barycentre) = 100mm Bruit/Signal ~ 1% • ADC 11 bits, 4 échantillons temporels à 100 ns
d-Au sample Di-electron analysis Di-muons analysis Mass Resolution ~ 100 MeV Mass Resolution ~ 150 MeV
peripheral central NA50 at CERN …
Ordinary absorption NA50 ANOMALOUS J/ SUPPRESSION
Beam EZDC (GeV)
With E T With EZCD
ψ χ ’ ψ’ ε 1 2 3 4 5 Suppression Satz et al.
NA50 Suppression ψ χ ’ ψ’ Satz et al. ε 1 2 3 4 5
NA50 Evidence for ψ χ ψ’ Screening Effects
ψ’ Suppression ψ χ ’ ψ’ Satz et al. ε 1 2 3 4 5
DECONFINEMENT !!! High Energy Physics Heavy Ion Physics
Heavy Ion Physicists Life is tough
WITH PLASMA t = 0 c c - Screening effects - hard gluon scattering Deconfinement c c t 2 fm/c mixed phase c d t 5 fm/c c d Hadronization D D Hadronic gas J/ψ J/ψ 10 fm/c t 20 fm/c Freeze-out
S-U Pb-Pb R.Rapp Regeneration : answer from RHIC
ψ’ Suppression ψ χ ’ ψ’ Satz et al. ε 1 2 3 4 5
Heavy Ion Physicists Life is tough
D- D+ CHARMONIA DISSOCIATION J/ p J/ +protons (neutrons) open charm
L = path length abs. Glauber absorption model Rarely produced (no multi-production) Uniforme (inside the nucleus) production probability • Short ( 1fm/c) formation time • straight line trajectories
data model Does it work ?? Yes
antiproton CERN :abs. = 21.4 2 mb BNL :abs. = 24.8 3 5 mb
Drell-Yan Glauber absorption model Drell-Yan no absorption abs. 0