The PANDA detector at the future FAIR laboratory

Klaus Föhl on behalf of the PANDA collaboration

12 July 2007

SPIN-Praha-2007 and Edinburgh

8 August 2007

• Gesellschaft für Schwerionenforschung in Darmstadt, Germany

• German National Lab for Heavy Ion Research

• Highlights:– Heavy ion physics

(i.e.tsuperheavies)– Nuclear physics– Atomic and plasma physics– Cancer research

Nuclei Far From StabilityHadron SpectroscopyCompressed Nuclear MatterHigh Energy Density in Bulk

Rare-Isotope BeamsAntiprotonsN-N Collisions at High EnergyIon Beam Induced Plasmas

The new FAIR

Rare-Isotope BeamsAntiprotonsN-N Collisions at High EnergyIon Beam Induced Plasmas

Nuclei Far From StabilityHadron SpectroscopyCompressed Nuclear MatterHigh Energy Density in Bulk

The new FAIR

Facility for Antiprotonand Ion Research

Primary Beams

•1012/s; 1.5 GeV/u; 238U28+

•Factor 100-1000 present in intensity•2(4)x1013/s 30 GeV protons•1010/s 238U73+ up to 25 (- 35) GeV/u

Secondary Beams

•Broad range of radioactive beams up to 1.5 - 2 GeV/u; up to factor 10 000 in intensity over present •Antiprotons 3 (0) - 30 GeV

Storage and Cooler Rings

•Radioactive beams•e – A collider

•1011 stored and cooledm 0.8 - 14.5 GeV antiprotons

•Cooled beams•Rapidly cycling superconducting magnets•Parallel operation

Key Technical Features

Facility for Antiprotonand Ion Research

CBM

PAX

HE

SR

CBM

Q: Why do we want to build yet another heavy-ion experiment?

What does theory expect? → Predictions from lattice QCD:

• crossover transition from partonic to hadronic matter at small B and high T

• critical endpoint in intermediate range of the phase diagram

• first order deconfinement phase transition at high B but moderate T

Use heavy-ion experiments as tools in order to study the QCD phase diagram!

hea

t

compression

CBM - Physics case

CBM - Experiment• tracking, momentum determination, vertex reconstruction: radiation hard silicon pixel/strip detectors (STS) in a magnetic dipole field

• hadron ID: TOF (& RICH)• photons, 0, : ECAL

• electron ID: RICH & TRD suppression 104

• PSD for event characterization• high speed DAQ and trigger

• muon ID: absorber + detector layer sandwich move out absorbers for hadron runs

MVD + STS

aim: optimize setup to include both, electron and muon ID (not necessarily simultaneously)

high interaction ratelong beamtime→ rare probes!

HESR

HESR - High Energy Storage Ring

injection from RESR • antiprotons• protons at reversed field polarities

injection from SIS 18 • protons 12.7 Tm in SIS

N

from RESR

Storage ring for p: Np = 5×1010, Pbeam= 1.5-15 GeV/c;

High density target: pellet 4×1015 atoms/cm2, cluster jet,

wire;

High luminosity mode: Δp/p = 10-4, stochastic cooling,

L = 1032 cm-2s-1;

High precision mode: Δp/p = 3×10-5, electron cooling,

L = 1031 cm-2s-1.

HESR

( ≤ 8.9 GeV/c)

( ≥ 3.8 GeV/c)

Circumference 574 m

longit

udina

l

horizontal

vertical

PAX

http://www.fz-juelich.de/ikp/pax

Polarized Antiproton ExperimentsPolarized Antiproton Experiments

… the [QCD-] PAC would like to stress again the uniqueness of the program with polarized anti-protons and polarized protons that could become available at GSI.

MAIN PHYSICS ISSUES

• Transversity measurement via Drell-Yan– Direct and unique measurement of transversity

• Electromagnetic Form Factors in the time-like region– First measurement of relative and absolute phase

• Double-polarized elastic pbar-p scattering– Same mysteries as in p-p case?

Cerenkov

Xeepp

pppp

Asymmetric collider: polarized antiprotons in HESR (p=15

GeV/c) polarized protons in CSR (p=3.5

GeV/c)

Fixed target experiment: pol./unpol. pbar internal H polarized target

Proton EFFs

eepp

pbar-p elastic

Drell-Yan

Designed for Collider but compatible with fixed target

Detector Concept

Antiproton Polarizer Ring (APR) Cooler Storage Ring (CSR) High Energy Synchrotron Ring (HESR)

Experimental SetupExperimental Setup ResultsResults

F. Rathmann. et al., PRL 71, 1379 (1993)

T=23 MeV

Polarising antiprotons?1992 Filter Test at TSR with protons1992 Filter Test at TSR with protons

First step of experimental Proof of PrincipleFirst step of experimental Proof of Principle

has neverbeen doneso far ...

Atomic Beam Source

SC Quadrupoles

Detector System surroundingStorage Cell Target

Common Experimental Setup for COSY and AD

Spin filtering works (for protons) but:1. Controversial interpretations of only experiment with

protons2. No experimental basis for antiprotonsExperimental tests needed with:

1. Protons at COSY2. Antiprotons at AD

Spin-filtering experiments

•Outstanding physics potential of polarized antiprotons

•Different proposals for polarizing antiprotons, but only one experimentally tested method (spin-filtering)

•COSY will play a fundamental role in understanding the spin filtering process and in commissioning for the decisive experiment with antiprotons at ADTIMELINE

2007-2008 Depolarization studies at COSY

2009-2010 Spin-filtering studies at COSY

Commissioning of AD experiment

2010 Installation at AD

2010-2011 Spin-filtering studies at AD

Conclusions PAX

The STI believes that PAX should become part of the FAIR core research program based on its strong scientific merit once the open problems are convincingly solved.

Physics

Core programme of PANDA

• Hadron spectroscopy– Charmonium spectroscopy– Gluonic excitations (hybrids, glueballs)

• Charmed hadrons in nuclear matter

• Double -Hypernuclei

Core programme of PANDA

Charmonium Spectroscopy

• Inconsistency in c mass and width

• η´c unambiguously

seen, although disagreement on the mass

• hc seen with poor statistics

• States above DD thr. are not well established

• New resonances...

Who ordered

that?

• e+e- interactions:– Only 1-- states are directly formed;

• pp reactions:– All meson states directly formed

(very good mass resolution)

– other states (spin exotic) can be studied using production mechanism.

Core programme of PANDA

• Hadron spectroscopy– Charmonium spectroscopy– Gluonic excitations (hybrids, glueballs)

• Charmed hadrons in nuclear matter

• Double -Hypernuclei

• further topics– Form Factors, GPDs?– Drell Yan?– Polarisation?

UNPOLARISED Drell-Yan

[2] D. Boer et al., Phys. Rev. D60 (1999) 014012.

DIRECT MEASUREMENT!!

SSA in SIDIS: convoluted with other PD and QFF functions;SSA in DY: convoluted with h1.

ANTIPROTONS!! DY azimuthal asymmetries not suppressed by nonvalence-like contributions. GDA can be investigated in γ and (neutral) meson production

)κ,(xh )κ(xh asymmetry )cos(2 211

22,1

1

Spin physics at PANDA?

Spin physics at PANDA

Polarisation? Look at the final state particles, i.e. self-analysing decays.

Setup

PANDA Side View

Pbar AND A AntiProton ANihilations at DArmstadt

Detector Capabilities• High Rates

– 107 interaction/s

• Vertexing– KS

0, Y, D, …

• Charged particle ID– e±, μ±, π±, K, p,…

• Magnetic tracking• EM. Calorimetry

– γ,π0,η

• Forward capabilities– leading particles

• Sophisticated Trigger(s)

PANDA Detector

beam

Top View

PANDA Detector

beam

Top View

pellet or cluster jet target

solenoid magnet for high pt tracks

- superconducting coil - iron return yoke

dipole magnetfor forward tracks

PANDA Detector

beam

Top View

silicon microvertexdetector

centraltracker

forward driftchambers

Central Tracker Options

Time-Projection ChamberTime-Projection Chamber Straw Tube TrackerStraw Tube Tracker

must be self-quenching

PANDA Detector

beam

Top View

forwardRICH

barrelDIRC

barrelTOF

endcapDIRC

forwardTOF

muondetectors

Cherenkov Detectors

• HERMES-style RICH

• BaBar-style DIRC

• disc DIRC

4 instead of 2 mirrors

front view

LiF

side view

fused silica

Focussing & Chromatic Correction

focussingelement

Focussing & Chromatic Correction

higherdispersionglass

Focussing & Chromatic Correction

higherdispersionglass

current implementation:fused silica radiator disc,LiF plates for dispersioncorrection and focussinglightguides around the rim

Focussing disc DIRC

focussing is better than 1mmover the entire linechosen as focal plane

light stays completelywithin mediumall total reflectioncompact designall solid materialflat focal plane

radiation-hard “glass”RMS surface roughnessat most several Ångström

LiF for dispersion correctionhas smaller |dn/d| than SiO2

fused silica

foca

l pla

ne c

oord

. [m

m]

lightguide number

lightguide “200mm”

rectangularpixel shape

LiF

Material Test

Testing transmission and total internal reflectionof a fused silica sample (G. Schepers and C. Schwarz, GSI)

PANDA Detector

beam

Top View

PWOcalorimeters

ForwardShashlykEMC

hadroncalorimeter

photon detection1MeV – 10GeV

operate at -25oC

Hypernuclei Setup

DAQ and Computing

Outlook

• PANDA will be a versatile QDC detector

• novel techniques in detector and readout design

• Technical Design until 2009

• Commissioning in 2014

Summary

• 30 years after the discovery of the c-quark charmonium systems still have many puzzles

• Many new charmonium and open charm states have been recently found by e+e- colliders:– No coherent picture → their properties like width and

decay channels have to be studied systematically with high precision.

• The PANDA detector will perform high resolution spectroscopy with p-beam and provide new data on this topic. σM ≈ 20 keV at GeVs 4

Panda Participating Institutes more than 300 physicists (48 institutes) from 15 countries

U BaselIHEP BeijingU BochumU BonnU & INFN BresciaU & INFN CataniaU CracowGSI DarmstadtTU DresdenJINR Dubna (LIT,LPP,VBLHE)U EdinburghU ErlangenNWU EvanstonU & INFN FerraraU FrankfurtLNF-INFN Frascati

U & INFN GenovaU GlasgowU GießenKVI GroningenU Helsinki IKP Jülich I + IIU KatowiceIMP LanzhouU MainzU & Politecnico & INFN MilanoU MinskTU MünchenU MünsterBINP NovosibirskLAL Orsay

U PaviaIHEP ProtvinoPNPI GatchinaU of SilesiaU StockholmKTH StockholmU & INFN TorinoPolitechnico di TorinoU Oriente, TorinoU & INFN TriesteU TübingenU & TSL UppsalaU ValenciaIMEP ViennaSINS WarsawU Warsaw

thank you all for coming