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Lars Schmitt, GSI Hadron 2011, Munich, June 17 2011

FAIR and PANDA Hadron Spectroscopy Hadron Structure Outlook: Beyond PANDA Facility for Antiproton and Ion Research

FAIR and PANDA L. Schmitt, GSI Facility for Antiproton and Ion Research

HESR

100 m PANDA

FAIR and PANDA L. Schmitt, GSI Characteristics of FAIR

Existing Storage and cooler rings Radioactive beams e-- A (or p - A) collider Antiprotons New

FAIR and PANDA L. Schmitt, GSI Characteristics of FAIR

Physics pillars: Primary beams Nuclear structure, HI physics, atomic & plasma U up to 35 AGeV physics, material science and bio physics, Protons up to 30 GeV/c hadron physics with p 100-1000x more g kin Secondary beams rea b Broad range of rare und s ro eam isotopes, 10000x more : G t B 012 irs 2 8: F p: 0-15 GeV/c 201 Existing Storage and cooler rings Radioactive beams e-- A (or p - A) collider Antiprotons New

FAIR and PANDA L. Schmitt, GSI High Energy Storage Ring

HESR Parameters HESR Storage ring for internal target Initially also used for accumulation Electron Injection of p at 3.7 GeV/c cooler

Slow synchrotron (1.5-15 GeV/c) PANDA Luminosity up to L~ 2x1032 cm-2s-1 Cooling (stochastic & electrons) Energy resolution ~50 keV

Injection

FAIR and PANDA L. Schmitt, GSI Physics Goals of PANDA

HadronHadron SpectroscopySpectroscopy Observables: masses, widths & quantum numbers JPC of resonances Charm Hadrons: charmonia, D-mesons, charm baryons ➔ Understand new XYZ states, Ds(2317) and others Exotic QCD States: glueballs, hybrids, multi-quarks Spectroscopy with Antiprotons: Production of states of all quantum numbers Resonance scanning with high resolution HadronHadron StructureStructure Generalized Parton Distributions ➔ Formfactors and structure functions, Lq Timelike Nucleon Formfactors Drell-Yan Process

FAIR and PANDA L. Schmitt, GSI Physics Goals of PANDA

FAIR and PANDA L. Schmitt, GSI The PANDA Experiment

Detector requirements: 4π acceptance

High rate capability: 2x107 s-1 interactions Efficient event selection ➔ Continuous acquisition

Momentum resolution ~1% 0 Vertex info for D, K S, Y (cτ = 317 µm for D±) ➔ Good tracking

Good PID (γ, e, µ, π, K, p) ➔ Cherenkov, ToF, dE/dx

γ-detection 1 MeV – 10 GeV ➔ Crystal Calorimeter

FAIR and PANDA L. Schmitt, GSI The PANDA Experiment

TARGET SPECTROMETER FORWARD SPECTROMETER Solenoid Target Dipole

p-Beam

FAIR and PANDA L. Schmitt, GSI The PANDA Experiment

TARGET SPECTROMETER FORWARD SPECTROMETER

Central GEM Micro Vertex Tracker Tracker Straw Chambers FAIR and PANDA L. Schmitt, GSI The PANDA Experiment

TARGET SPECTROMETER FORWARD SPECTROMETER Disc DIRC Muon ID RICH

Muon PWO Crystal Forward Range Barrel DIRC Barrel ToF Calorimeters ToF System

FAIR and PANDA L. Schmitt, GSI Hadron Spectroscopy

L. Schmitt, GSI Aims of Spectroscopy

Experiment: Systematic determination of particle properties Mass Lifetime or width of resonance Quantum number JPC

Theory: Calculation of spectra Knowing interaction allows prediction Tuning accounting for experimental data

Final aim: Understand composition and dynamics of matter In QCD we are still far away from precision of QED

Hadron Spectroscopy L. Schmitt, GSI Spectroscopy with Antiprotons

Spectroscopy with antiprotons

V 100 CBall pp machine allows ΔE ~ 50 keV (beam) e E835 M

+ − vs. ΔE ~5 MeV in e e (detector) 2 χ / c1 1000 .

+ − PC −− v e

e e directly produces only J = 1 (γ) b l l p a / .

others via ISR and other higher orders B v

l e a

t 5

pp accesses all states s 3 y 8 r

C E Resolution with antiprotons 3500 3510 3520 MeV E Resonance scan: CM Energy resolution ~50 keV

Tune ECM to probe

resonance ECM Get precise mass and width

Hadron Spectroscopy L. Schmitt, GSI

Quarkonia and Confinement C 1 fm C

Properties of Quarkonia

Mass gaps much smaller than mQ Q ➔ Non-relativistic bound systems due to the large mass of Q R Multiple scales: Q 2 m >> mv~1/R >> mv v

~ΛQCD

(v small) Quarkonium Spectroscopy At zero T: probe non-perturbative, perturbative and transition region Quarkonia in matter At finite T: color screening in QGP

➔ Tool to understand confinement

Hadron Spectroscopy L. Schmitt, GSI

Charmonium Spectroscopy C 1 fm C

Charmonium Status below DD threshold Positronium of QCD: JPC=1-- well measured Potential of cc calculable Low resolution on JPC=0-+ states

➔ Prediction of states ηc' was rediscovered 40 MeV higher

Low statistics on hc ) 2 c / V e M ( m

Hadron Spectroscopy L. Schmitt, GSI

New Charmonium States C 1 fm C

Renaissance in Charmonium Spectroscopy: Belle, BaBar, CLEO, CDF and D0 find new states above DD Many of these states are problematic: mass not predicted, width too small, decay pattern unusual Challenge for better understanding and high precision data

State Experiments Nature/Remarks X(3872) Belle, BaBar, CDF, D0 D0D0* molecule, 4-quark state

X(3943) Belle maybe η‘‘c 23 Y(3940) Belle maybe P1

Z(3930) Belle maybe χ‘c2

Y(4260) BaBar, Belle, CLEO-c Hybrid, ωχc1 -molecule, 4q state Y(4350) BaBar, Belle ? Z±(4430) Belle No charged cc, molecule or 4q state Y(4660) Belle ?

Hadron Spectroscopy L. Schmitt, GSI D-Meson Spectroscopy

Heavy mesons like H-atom: Heavy quark surrounded by light quark ordered by property of light quark approximate j degeneracy ➔ Spectroscopic predictions ➔ Works fairly well in c(u/d) system

Hadron Spectroscopy L. Schmitt, GSI D-Meson Spectroscopy ] 2 c / j=L+sL V e

G J=j+s

[ H

m Ds1 D*K }j=3/2 D * s2 }j=1/2 Heavy mesons like H-atom: DsJ Heavy quark surrounded by light quark (2460) D0K D * * sJ ordered by property of light quark Ds (2317) approximate j degeneracy Ds ➔ Spectroscopic predictions ➔ Works fairly well in c(u/d) system 0− 1− 0+ 1+ 2+ 3− D mesons surprise JP s D (2317) → D + π0, but not D + π+ π– Recent narrow D (2317) and D (2460) s0 s s s0 s1 D (2460) in D + π0γ, D +γ , D + π+π– do not fit theoretical calculations. s1 s s s Quantum numbers for the newest states Experimentally well established Nature unclear: 4q states, molecules? DsJ(2700) and DsJ (2880) open

Hadron Spectroscopy L. Schmitt, GSI Baryon Spectroscopy

Baryon Spectroscopy in PANDA Large cross section, no extra mesons 4π acceptance for charged and neutral Displaced vertex tagging N and Δ Baryons N* spectrum not understood Missing resonances Strange Baryons Little known about Ξ and Ω resonances Hardly any progress since 20 years Charmed Baryons Narrow widths of resonances Rich spectrum of states JPC not yet all measured Testing ground for HQET

Hadron Spectroscopy L. Schmitt, GSI Exotic Hadrons

Exotic Hadrons Normal hadrons: (qq) or (qqq) Gluonic degrees of freedom: Hybrid mesons (qqg) Glueballs Multi-quark states Molecules Exotic mesons can have exotic quantum numbers

Mesons, Baryons

Multi-quarks

Hybrids

Glueballs

Hadron Spectroscopy L. Schmitt, GSI Exotic Hadrons

Exotic Hadrons Charm Spectroscopy Charm quark: m >> m Normal hadrons: (qq) or (qqq) c u,d,s Gluonic degrees of freedom: ➔ Perturbative to strong coupling Hybrid mesons (qqg) Charm Hybrids Glueballs c-states narrow, understood Multi-quark states Little interference of ccg & cc-states Molecules Mass 4–4.5 GeV, c c g narrow, Exotic mesons can have exotic quantum numbers ~ σ( p p → c c)

Mesons, Baryons

Multi-quarks

Hybrids

Glueballs

Hadron Spectroscopy L. Schmitt, GSI Hadron Structure

L. Schmitt, GSI Nucleon Spin Structure

Basics of nucleon structure studies: Bjorken scaling: At high Q2 dependence only on x: scatter on partons Parton distributions: ● Valence quarks ● Sea: quarks and antiquarks ● Gluons Structure Functions:

● Unpolarized F1 and F2

● Polarized g1 (and g2)

● Transverse polarized h1 Proton spin status:

=½ =½ (Δu+Δd+Δs)+Lq+ΔG+LG Expt. Quark contribution: ΔΣ=(Δu+Δd+Δs) ≈ 0.3 Gluon polarisation: |ΔG/G| < 0.3 Other contributions: orbital angular momentum

Hadron Structure L. Schmitt, GSI Generalized Parton Distributions

WhatWhat GPDsGPDs are:are: Handbag Diagram A fractional momentum ξ is taken out GPDs: 4 functions H(x,ξ,t), E(x,ξ,t), ~ ~ H(x,ξ,t), E(x,ξ,t) (polarized) x+ξ x-ξ

GPD Quark distribution q(x), -q(-x) PropertiesProperties ofof GPDs:GPDs: GPDs carry information on longitudinallongitudinal and transverse distribution of partons GPDs contain also information on quark (orbital) angular momentum H(x,0,0) = q(x) structure functions of DIS M. Vanderhaeghen ∫H(x,0,t) dx = F(t) nucleon formfactor

Hadron Structure L. Schmitt, GSI GPDs in PANDA

p p Generalized Parton Distributions Meson Deeply virtual Compton scattering Hard exclusive meson production GDAs GDAs

Crossed channels with p p p Wide angle Compton scattering Hard exclusive meson production

Simulation Signal: pp→γγ Backgrounds: pp→γπ0, pp→π0 π0

Hadron Structure L. Schmitt, GSI Transition Distribution Amplitudes

From GPDs to TDAs: GPDs describe qq exchange TDAs describe qqq exchange: ➔ Backward exclusive meson production ➔ Process pp → γγ*

Properties of TDAs: Universal non-perturbative objects describing e.g. p → π and p → γ Obey QCD evolution equations

Feasibility Studies Cross section in reach for PANDA Signal: pp→γe+e– and pp→π0γ Backgrounds: pp→γπ0, pp→π0 π0

Hadron Structure L. Schmitt, GSI Drell-Yan Process in PANDA

Transverse nucleon spin Drell Yan Process p (full PWA or polarized beam/target) e,µ No helicity flip fragmentation function needed as in DIS With pp access valence antiquarks p e,µ High x, high cross section, high sensitivity First unpolarised only Later: single spin asymmetry

Hadron Structure L. Schmitt, GSI Electromagnetic Formfactors

Accessing electromagnetic formfactors of nucleon

Discrepancy between timelike and spacelike region: GM(TL) ≈ 2GM(SL) Measure pp→e+e-

Scattering: spacelike FF, Annihilation: timelike FF q2<0 2 2 q >4 M p

Hadron Structure L. Schmitt, GSI Outlook: Beyond PANDA

L. Schmitt, GSI Polarisation in PANDA

Polarised target in PANDA: Transversely polarised protons increase PANDA physics potential SSA in Drell Yan Phase difference between GE and GM Polarised target inside solenoid difficult Exploit modular upstream design with storage cell Counter solenoid to compensate spectrometer magnet at up to 1 T BESS-Polar ultra thin solenoid 2 (1 g/cm Al/Nb, 0.11 X0) Polarised proton beam: as model for the counter solenoid Mid-term option using snake in HESR: a preparation to ENC or PAX

Outlook: Beyond PANDA L. Schmitt, GSI Electron Nucleon Collider

Physics with polarized e and p Transversity Precision ΔG/G Polarized GPDs Accelerator setup: Polarized p-source Acceleration of p in HESR High energy e-cooler Electron accelerator chain Modified PANDA Thin counter solenoid Narrow beam crossing

Outlook: Beyond PANDA L. Schmitt, GSI Polarized Antiprotons in PAX

Physics with polarized p Transversity with Drell Yan ➔ Double polarisation ➔ No spin-flip as in DIS Polarized GPDs Production of polarized p Spin filter method at low p Acceleration of p in HESR Collision with p from CSR Experiment PAX Phase I: Fixed target Phase II: Collider Detector designed for both

Outlook: Beyond PANDA L. Schmitt, GSI Conclusions

Hadron physics sees a significant renaissance New observations probe our present understanding Similar methods and input from different fields Spectroscopy, Structure and Symmetry Studies merge New methods enlarge our horizon Theory: fundamental methods based on low energy QCD Computing: lattice gauge theory, coupled channels, PWA Future hadron facilities: GLUE-X, J-PARC, PANDA at FAIR Experiments: precision detectors with flexible readout PANDA & FAIR become important in hadron physics from 2018 Versatile physics machine with full detection capabilities PANDA will shed light on many of today's QCD puzzles Beyond PANDA further plans for spin physics at FAIR exist

L. Schmitt, GSI