Concept of the PANDA Detector for pp&pA at GSI

• Physical motivation for hadron physics with pbars• The antiproton facility• Detector concept• Selected simulation results• Conclusions

James Ritman Univ. Giessen

Physical Motivation

1. Quantitative understanding of quark confinement

Charmonium (Bettoni, Koch)

2. Do hadrons other than mesons and baryons exist?

glueballs and/or hybrids (Peters)

3. The mass of hadrons is much larger than the sumof the valence current quark masses. (SBS)

p A interactions4. Nuclear spectroscopy and the study of

baryon-baryon interactions double hypernuclei

(Pochodzalla)• Future options (Poster: Ganzhur&Koch)

Overview talk by W. Henning

The GSI p Facility

HESR = High Energy Storage Ring

• Production rate 2x107/sec• Pbeam = 1 - 15 GeV/c• Nstored = 5x1010 p

High luminosity mode• Lumin. = 2x1032 cm-2s-1 • p/p~10-4 (stochastic cooling)

High resolution mode• p/p~10-5 (el. cooling < 8 GeV/c)• Lumin. = 1031 cm-2s-1

General Purpose Detector

Detector requests:

• nearly 4 solid angle (partial wave analysis)• high rate capability (2107 annihilations/s)• good PID (, e, , , K, p)• momentum resolution (~1%)• vertex info for D, K0

S, cm for D• efficient trigger (e, , K, D, )• modular design (Hypernuclei experiments)

Detector Concept

target spectrometer forward spectrometer

micro vertexdetector

electromagneticcalorimeter

DIRC:Detecting InternallyReflectedCherenkov light

straw tubetracker

mini driftchambers

muon counter

Solenoidalmagnet

iron yoke

Target• A fiber/wire target will be needed for D physics,• A pellet target is conceived:

1016 atoms/cm2 for D=20-40 m

1 mm

MVD

Conversion Prob: ~3%,primary e+e- ~3.6%

Central Tracking Detectors

example event: pp 4K

• MVD: (Si) 5 layers• Straw-Tubes: 15 skewed double-layers• Mini-Drift-Chambers

Tracking Resolution

J/ +-

+- (J/ = 35 MeV/c2

( = 3.8 MeV/c2

Example reaction: pp J/ + (s = 4.4 GeV/c2)

Single track resolution

Invariant mass resolution

PID with DIRC

                                                                           

(DIRC@BaBar)

GEANT4 simulationfor HESR:

PbWO4 Calorimeter

Length = 17 X0

APD readout (in field)

pp J/

e/-Separation

Muon Detector

Performance of Spectrometer

Probability to measure the reaction:

GeV4.4/ sJpp J/ ee J/

Simulations Framework

Event Generation (FS) DPM pbar + p background

PndEvtGen selected channels

PndSimAppGEANT4 modeling of the detector

PndRecoApptracking, EMC cluster finding, RICH ring

finding,...

PandaApp (FastSim) „user analysis“, PID, spectra, ...

Summary

• HESR: cooled antiprotons up to 15 GeV/c

• Wide program in hadron physics

• Detector concept

• Selected simulation results

Pressemitteilung 05.02.2003

Bulmahn gives green light for large-scale research equipment "We are securing an international top position for German basic research"

…

Together with European partners, the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt is to develop further its equipment in a phased approach and become a leading European physics centre. At least 25% of the costs amounting to €675 million are to be shouldered by foreign partners.

Neutral Vertex Finder

K0S

+

-

-

+ -

Reaction: 2K0s

|D0|>0.4 mm or |Z0|>0.5 mm for each track

Kinematic refit (constraint=common vertex)

3-Momentum conservation

Forward Spectrometer

What Can Antiproton Beams Contribute to this

Discussion?Much lower momentum for heavy producedparticles (2GeV for “free”)

(Mass shifts are smaller at high momentum)

Open charm mass region (H atom of QCD) @HESR

(single light quark)

Well defined nuclear environment (T and )