The PANDA Detector at FAIR Lars Schmitt, GSI Darmstadt VCI '07, Vienna, February 22nd 2007 The Facility PANDA Physics Spectrometer Overview Tracking in PANDA Particle Identification Calorimetry in PANDA Conclusion & Outlook

Facilitiy for Antiproton and Ion Research GSI, Darmstadt German National Lab for Heavy Ion Research Highlights: - Heavy ion physics - Nuclear physics - Atomic and plasma physics - Cancer research FAIR: New facility RIB Heavy ions higher intensities & energies Antiprotons The Facility L. Schmitt, VCI '07

Storage and Cooler Rings Key Technical Features Layout of FAIR Primary Beams 238U28+ : 1012/s @ 1.5-2 AGeV; 238U92+: 1010/s @ up to 35 AGeV Protons : 2 x1013/s @ 30 GeV; up to 90 GeV 100-1000 times present intensity SIS 100/300 SIS UNILAC FRS Secondary Beams Broad range of radioactive beams up to 1.5 - 2 AGeV intensity up to 10 000x over present Antiprotons 0 - 15 GeV ESR HESR Existing New Super FRS Storage and Cooler Rings Radioactive beams e-– A (or Antiproton-A) collider 1011 stored and cooled antiprotons 0.8 - 14.5 GeV/c Future: Polarized antiprotons (?) CR RESR FLAIR NESR Cooled beams Rapidly cycling superconducting magnets Parallel Operation Key Technical Features The Facility L. Schmitt, VCI '07

HESR – Storage Ring for Antiprotons Injection of p at 3.7 GeV Slow synchrotron (1.5-14.5 GeV/c) Storage ring for internal target operation Luminosity up to L~ 2x1032 cm-2s-1 Beam cooling (stochastic & electron) ECM Resonance Scan PANDA The Facility L. Schmitt, VCI '07

Stronq coupling constant vs R PANDA Physics Structure & Dynamics of Hadrons in the transition regime of QCD Why don’t we observe free quarks? Charmonium spectroscopy → Quark confinement How are color neutral states formed? Hadrons (qqq or qq) Gluonic excitations Multi-quark systems → QCD predictions How do hadrons obtain mass? p-A interactions Meson properties in nuclear medium → Restoration of chiral symmetry What is the structure of the nucleon? Hard scattering processes & soft fragmentation → From partons to hadrons Stronq coupling constant vs R perturbative strong QCD PANDA Physics

Hadron Spectroscopy Spectroscopy with antiprotons χc1 pp machine allows ΔE ~ 100 keV vs. ΔE ~ 10 MeV in e+e− obtain m and Γ with high precision e+e− directly produces only JPC = 1−− (γ) pp accesses all states Charm spectroscopy Charmonium: Positronium of QCD Charm hybrids c-states narrow, understood Little interference between ccg and cc-states Mass 4–4.5 GeV, c c g narrow, ~ σ( p p → c c) Charm meson spectroscopy 3500 3520 MeV 3510 Crystal Ball ev./2 MeV 100 ECM CBall E835 χc1 1000 E 835 ev./pb PANDA Physics

Nuclear Physics in PANDA Charm in the Medium Mesons in nuclear matter Masses change in nuclei D-mass lower Enhanced charmonium states due to lower D D threshold J/ψ absorption in nuclei ¯ Hypernuclei 3rd dimension in nuclear chart Study interactions of nucleons in the nuclear potential PANDA: Double Hypernuclei Production via Ξ- capture Λ Λ interaction in nucleus PANDA Physics

Electromagnetic Processes Electromagnetic formfactors Discrepancy between timelike and spacelike region Measure pp→e+e- Generalized Parton Distributions Wide angle Compton scattering Hard exclusive meson production Transverse nucleon spin Drell Yan Process (full PWA or polarized beam/target) p p Vector meson GPDs GPDs p p p e,µ p e,µ PANDA Physics

Detector Requirements Physics benchmarks: Hybrid charmonium e.g. 7 photons, PWA Charmonium decays e.g. J/Ψ→ e+e- and µ+µ-, or with π0 & γ Charm mesons Weak decays in K0S and K± Hypernuclei Hyperon cascades Wide angle Compton scattering High energy photons Proton formfactors Efficient e± identification Detector requirements: nearly 4 solid angle for PWA high rate capability: 2x107 s-1 interactions efficient event selection momentum resolution ~1% vertex info for D, K0S,  (c = 317 m for D±) good PID (, e, , , K, p) photon detection 1 MeV – 10 GeV Spectrometer Overview

PANDA Spectrometer Spectrometer Overview

PANDA Spectrometer Pellet or cluster jet target Dipole magnet for forward tracks Solenoid magnet for high p t tracks: Superconducting coil & iron return yoke Spectrometer Overview

Forward Drift Chambers PANDA Spectrometer Silicon Microvertex Central Tracker Forward Drift Chambers Spectrometer Overview

PANDA Spectrometer Muon Detectors Forward RICH Barrel DIRC Barrel TOF Endcap DIRC Forward TOF Spectrometer Overview

PANDA Spectrometer PWO Calorimeters Forward Shashlyk EMC Hadron Calorimeter Spectrometer Overview

Data Acquisition and Trigger Self-triggering readout Components Time distribution system Intelligent frontends Powerful compute nodes Configurable high speed network Data Flow Data reduction First selection at high rate Further selections at lower rates, but with more detectors Data logging after online reconstruction Programmable Physics Machine Spectrometer Overview

Silicon Micro Vertex Detector Layout of MVD General structure: 4 Barrels & 6 disks Inner layers pixels Outer layers strips (forward mixed) Pixel part: Hybrid pixels 100 x100 µm2 140 modules 13 M channels 0.15 m2 Strip part: Double sided silicon 400 modules 70k channels 0.5 m2 Beam pipe Barrels Target pipe Disks Tracking in PANDA

Silicon Micro Vertex Detector Readout of MVD Self-triggering electronics Pixel readout: Custom pixel chip TOPIX: ASIC in 0.13µm CMOS First prototype: Preamp & discriminator Analog output Microstrip readout: 128-channel ASIC for strips Prototype n-XYTER chip for DETNI Fast timing shaper/amplifier with comparator Slow channel for analog r/o with peak detector Token ring readout of hit channels Next iteration with lower power consumption Tracking in PANDA

Central Tracker – STT Option 5340 straws in 21-27 layers Al-mylar film tube: 10.0  0.03  1500 mm (ØdL) rin/rout: 160 / 420 mm, V = 610 l Self-supporting straw layers at ~1 bar overpressure (Ar/CO2) Straw pitch: 10 mm 15 kg straw weight Axial layers: r ~ 150µm, A   ~ 98% Skewed layers: z ~ 2.9 mm, A   ~ 90-95% Radiation length: X/X0 ~ 1.0-1.3 % pt / pt ~ 1.2 % Tracking in PANDA

Central Tracker – STT Option 5340 straws in 21-27 layers Al-mylar film tube: 10.0  0.03  1500 mm (ØdL) rin/rout: 160 / 420 mm, V = 610 l Self-supporting straw layers at ~1 bar overpressure (Ar/CO2) Straw pitch: 10 mm 15 kg straw weight Axial layers: r ~ 150µm, A   ~ 98% Skewed layers: z ~ 2.9 mm, A   ~ 90-95% Radiation length: X/X0 ~ 1.0-1.3 % pt / pt ~ 1.2 % Tracking in PANDA

Central Tracker – STT Option 5340 straws in 21-27 layers Al-mylar film tube: 10.0  0.03  1500 mm (ØdL) rin/rout: 160 / 420 mm, V = 610 l Self-supporting straw layers at ~1 bar overpressure (Ar/CO2) Straw pitch: 10 mm 15 kg straw weight Axial layers: r ~ 150µm, A   ~ 98% Skewed layers: z ~ 2.9 mm, A   ~ 90-95% Radiation length: X/X0 ~ 1.0-1.3 % pt / pt ~ 1.2 % Tracking in PANDA

Central Tracker – TPC Option General layout: GEM-TPC 2 half cylinders Drift field E || B Gas: Ne/CO2 (+CH4/CF4) Multi-GEM stack for amplification and ion backflow suppression 100 k pads of 2 x 2 mm2 50-70 µs drift, 500 events overlap Simulations: p/p ~ 1% dE/dx resolution ~ 6% Challenges: space charge build-up continuous sampling Tracking in PANDA

Central Tracker – TPC Option General layout: GEM-TPC 2 half cylinders Drift field E || B Gas: Ne/CO2 (+CH4/CF4) Multi-GEM stack for amplification and ion backflow suppression 100 k pads of 2 x 2 mm2 50-70 µs drift, 500 events overlap Simulations: p/p ~ 1% dE/dx resolution ~ 6% Challenges: space charge build-up continuous sampling Tracking in PANDA

Particle Identification PANDA PID Requirements: Particle identification essential for PANDA Momentum range 200 MeV/c – 10 GeV/c Different process for PID needed PID Processes: Cherenkov radiation: above 1 GeV Radiators: quartz, aerogel, C4F10 Energy loss: below 1 GeV Best accuracy with TPC Time of flight Problem: no start detector Electromagnetic showers: EMC for e and γ dE/dX by TPC Forward ToF More details on PID in PANDA: see Poster B41 by Björn Seitz in Session B Particle Identification

DIRC Concept Detection of Internally Reflected Cherenkov light Different Cherenkov angles give different reflection angles PANDA DIRC similar to BaBar 96 Fused silica bars, 2.6m length Water tank & 7000 PMTs Alternative readout: (x,y,t), mirrors Schwiening Schwiening Particle Identification

PANDA Endcap DIRC Setup of Endcap Cherenkov DIRC principle Disc shaped fused silica radiator 2.1 m diameter Measure coordinate and time Dispersion correction through dichroic filters or second coordinate Sato Particle Identification

Electromagnetic Calorimeters Backward Endcap 800 Crystals Worse resolution due to service lines of trackers Needed for hermeticity Barrel Calorimeter 11000 PWO Crystals LA APD readout σ(E)/E~1.5%/√E + const. Forward Endcap 4000 PWO crystals High occupancy in center Readout LA APD or vacuum triodes Forward Shashlyk (after dipole magnet) 350 channels Readout via PMTs σ(E)/E~4%/√E + const. Alternative Designs: Spiral Shashlyk Segmented composite Shashlyk-Sandwich for for (e/h/µ) Calorimetry in PANDA

PANDA PWO Design Benefits of PWO Challenges High density → compact detector Hermetic coverage and fine granularity Fast scintillator Good resolution Challenges Radiation damage of crystals Temperature stabilization to 0.1oC In PANDA: Low energy photons (few MeV) Increase PWO light yield Operation at -25oC Higher output crystals PWO-II from BCTP Large area APDs Crystal Design Tapered PWO crystals Length 200mm, front face 20x20 mm2 Offers from Bogoroditsk, Shanghai, Apatiti Carbon fibre alveoles as housing Calorimetry in PANDA

Conclusion & Outlook will be a versatile QCD experiment: Large acceptance and double spectrometer Tracking and vertexing capabilities Particle identification and calorimetry Flexible data acquisition & trigger Novel techniques in detector and readout design Technical Design until 2009 Commissioning in 2014

The PANDA Collaboration More than 350 physicists from 48 institutions in 15 countries U Basel IHEP Beijing U Bochum U Bonn U & INFN Brescia U & INFN Catania U Cracow GSI Darmstadt TU Dresden JINR Dubna (LIT,LPP,VBLHE) U Edinburgh U Erlangen NWU Evanston U & INFN Ferrara U Frankfurt LNF-INFN Frascati U & INFN Genova U Glasgow U Gießen KVI Groningen U Helsinki IKP Jülich I + II U Katowice IMP Lanzhou U Mainz U & Politecnico & INFN Milano U Minsk TU München U Münster BINP Novosibirsk LAL Orsay U Pavia IHEP Protvino PNPI Gatchina U of Silesia U Stockholm KTH Stockholm U & INFN Torino Politechnico di Torino U Oriente, Torino U & INFN Trieste U Tübingen U & TSL Uppsala U Valencia SMI Vienna SINS Warsaw U Warsaw