Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Charmed Hadrons in Matter Introduction Medium Effects in the light quark sector Expectations for the charm quark sector J/  -N interaction Requirements for the Experiment Conceptual Design Conclusions

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Introduction Origin of Hadron Masses ? Chiral Symmetry in QCD is spontaneously broken Mass Modifications due to Chiral Dynamics Partial Restoration of C.S. in Hadronic Environment

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Deeply bound Pionic States 206 Pb(d, 3 He) Pion-Nucleus Potential from binding energy and width isospinasymmetric matter,    0 m(  - ) increased by  25 MeV A. Gillitzer, Hirschegg ‘01

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Production of Open Strangeness Excitation function for K + /K - production in H.I. Reactions Different from elementary reaction: enhanced  (K - ) K - mass lowered by  100 MeV (  0 ) F. Laue, EPJ A9 397

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Expectations for charmed Mesons J/ , η c : -5 to -10 MeV D-Mesons “Hydrogen of QCD” - mass lowering - 50 MeV mass split Charm quark mass: GeV

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Consequences for Observables A. Sibirtsev EPJ A6 351 DD production will be enhanced below threshold D-mesons decay semi- leptonic (10-20% BR) Cross sections  1 nb near threshold D,D,D s,D s,J/ ,  ’

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Consequences for Observables II  Threshold lowered by  100 MeV  “new” decay channels open (  ’,χ c2 )  width increases   (3770) broadening (lepton pair detection) A. Hayashigaki PLB487 96

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI J/  -N Absorption Cross Section In URHIC: suppression of J/  observed ?Hadronic Interactions? 3-4 mb from γN 6-7 mb from pA, AA  Antiproton annihilation on nuclei also for J/ ,  ’, χ J on various nuclear targets K.K. Seth, Hirschegg ‘01

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Dissociation of Charmonium p + d  D - + Λ c + cc interacts with residual neutron Studying energy dependence p + d  J /  +  + n: measuring  ( J /  -N ) elastic down to lower relative momenta J /  - meson scattering cross section A. Sibirtsev NPA c

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Requirements for the Experiment Production of charmed mesons  (DD)  1 nb  100 d L = 2·10 31 cm -2 s -1  high luminosity c  (D ± ) = 315 µm, c  (D S ) = 149 µm  well-defined interaction point  good vertex resolution (  100 µm ) D’s decay semileptonic (10 – 20 % B.R.) decay kinematics: high p t, large opening angles  momentum determination, PID

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Microvertex Tracking Silicon Pixel Detector, 200 µm wafers (0.25% X 0 ) 7.2 MPixels 50·300 µm² 2 MPixels 100·150 µm²

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Microvertex Tracking II Does the concept meet the requirements?  (  D 0 ) = 50 µm  (  Z 0 ) = 85 µm

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Momentum determination, PID Straw Tubes for tracking  xy = 150µm,  z = 1mm Drift chambers Separation of   /K  (DIRČ)

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Lepton identification Electromagnetic calorimeter (PbWO 4 ) 96% coverage of the solid angle Muon hodoscope (plastic scintillators)

Workshop on Experiments with Antiprotons at the HESR – April 2002, GSI Conclusions GSI has a successful history in studying medium effects in the light quark sector Extending the program to the charm quark sector promises exciting perspectives The proposed program requires a versatile detector in terms of resolution, PID, rate capability and triggering