Hadron P adron Physics hysics at at Lars Schmitt, GSI Hadron - - PowerPoint PPT Presentation

Outlook: Beyond PANDA Hadron Structure

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

Hadron Spectroscopy

Hadron P adron Physics hysics

FAIR and PANDA

at at

• L. Schmitt, GSI

Facility for Antiproton and Ion Research

FAIR and PANDA

• L. Schmitt, GSI

Facility for Antiproton and Ion Research

FAIR and PANDA

100 m PANDA HESR

• L. Schmitt, GSI

Characteristics of FAIR

FAIR and PANDA

New Existing

Primary beams U up to 35 AGeV Protons up to 30 GeV/c 100-1000x more Secondary beams Broad range of rare isotopes, 10000x more p: 0-15 GeV/c Storage and cooler rings Radioactive beams e-- A (or p - A) collider Antiprotons Physics pillars: Nuclear structure, HI physics, atomic & plasma physics, material science and bio physics, hadron physics with p

• L. Schmitt, GSI

Characteristics of FAIR

FAIR and PANDA

New Existing

Primary beams U up to 35 AGeV Protons up to 30 GeV/c 100-1000x more Secondary beams Broad range of rare isotopes, 10000x more p: 0-15 GeV/c Storage and cooler rings Radioactive beams e-- A (or p - A) collider Antiprotons Physics pillars: Nuclear structure, HI physics, atomic & plasma physics, material science and bio physics, hadron physics with p

2012: Ground breaking 2018: First Beams

• L. Schmitt, GSI

High Energy Storage Ring

FAIR and PANDA

HESR Parameters

Storage ring for internal target Initially also used for accumulation

Injection of p at 3.7 GeV/c

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

Electron cooler PANDA Injection HESR

• L. Schmitt, GSI

Physics Goals of PANDA

FAIR and PANDA

Hadron Hadron Spectroscopy Spectroscopy

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

• L. Schmitt, GSI

Physics Goals of PANDA

FAIR and PANDA

Hadron Hadron Spectroscopy Spectroscopy

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

Hadron Hadron Structure Structure

Generalized Parton Distributions

➔ Formfactors and structure functions, Lq

Timelike Nucleon Formfactors Drell-Yan Process

• L. Schmitt, GSI

Physics Goals of PANDA

FAIR and PANDA

Hadron Hadron Spectroscopy Spectroscopy

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

Hadron Hadron Structure Structure

Generalized Parton Distributions

➔ Formfactors and structure functions, Lq

Timelike Nucleon Formfactors Drell-Yan Process

Nuclear Physics Nuclear Physics

Hypernuclei: Production of double Λ-hypernuclei

➔ γ-spectroscopy of hypernuclei, YY interaction

Hadrons in Nuclear Medium

• L. Schmitt, GSI

The PANDA Experiment

FAIR and PANDA

• L. Schmitt, GSI

The PANDA Experiment

FAIR and PANDA

Detector requirements:

4π acceptance High rate capability: 2x107 s-1 interactions Efficient event selection

➔ Continuous acquisition

Momentum resolution ~1% Vertex info for D, K0

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

• L. Schmitt, GSI

The PANDA Experiment

FAIR and PANDA

TARGET SPECTROMETER FORWARD SPECTROMETER

Solenoid Dipole Target p-Beam

• L. Schmitt, GSI

The PANDA Experiment

FAIR and PANDA

Micro Vertex Central Tracker Straw Chambers GEM Tracker

TARGET SPECTROMETER FORWARD SPECTROMETER

• L. Schmitt, GSI

The PANDA Experiment

FAIR and PANDA

TARGET SPECTROMETER FORWARD SPECTROMETER

Muon ID RICH Barrel DIRC PWO Crystal Calorimeters Muon Range System Barrel ToF Forward ToF Disc DIRC

• L. Schmitt, GSI

Hadron Spectroscopy

• L. Schmitt, GSI

Aims of Spectroscopy

Hadron 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

• L. Schmitt, GSI

Spectroscopy with Antiprotons

Hadron Spectroscopy

Spectroscopy with antiprotons

pp machine allows ΔE ~ 50 keV (beam)

• vs. ΔE ~5 MeV in e+e− (detector)

e+e− directly produces only JPC = 1−− (γ)

• thers via ISR and other higher orders

pp accesses all states

Resolution with antiprotons

Resonance scan:

Energy resolution ~50 keV Tune ECM to probe resonance Get precise mass and width

3500 3520 MeV 3510

Crystal Ball ev./2 MeV

100

ECM

CBall E835

1000

E 835 ev./pb

χc1

ECM

• L. Schmitt, GSI

Quarkonia and Confinement

Hadron Spectroscopy

Properties of Quarkonia

Mass gaps much smaller than mQ

➔ Non-relativistic bound systems

due to the large mass of Q Multiple scales: m >> mv~1/R >> mv2 ~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

1 fm

C C

Q Q R v

• L. Schmitt, GSI

Charmonium Spectroscopy

Hadron Spectroscopy

Status below DD threshold

JPC=1-- well measured Low resolution on JPC=0-+ states ηc' was rediscovered 40 MeV higher Low statistics on hc

1 fm

C C

m(MeV/c2)

Charmonium

Positronium of QCD: Potential of cc calculable

➔ Prediction of states

• L. Schmitt, GSI

New Charmonium States

Hadron Spectroscopy

1 fm

C 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 Y(3940) Belle maybe 23P1 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 ?

• L. Schmitt, GSI

Heavy mesons like H-atom:

Heavy quark surrounded by light quark

• rdered by property of light quark

approximate j degeneracy

➔ Spectroscopic predictions ➔ Works fairly well in c(u/d) system

D-Meson Spectroscopy

Hadron Spectroscopy

• L. Schmitt, GSI

Heavy mesons like H-atom:

Heavy quark surrounded by light quark

• rdered by property of light quark

approximate j degeneracy

➔ Spectroscopic predictions ➔ Works fairly well in c(u/d) system

Ds mesons surprise

Recent narrow Ds0(2317) and Ds1 (2460) do not fit theoretical calculations. Quantum numbers for the newest states DsJ(2700) and DsJ (2880) open

D-Meson Spectroscopy

Hadron Spectroscopy

DsJ

(2460)

0− 1− 0+ 1+ 2+ 3− Ds Ds

*

DsJ

*

(2317)

Ds1 m [GeV/c2] D0K D*K Ds2

*

JP

}j=3/2 }j=1/2 j=L+sL J=j+sH

Ds0(2317) → Ds

+ π0, but not Ds + π+ π–

Ds1(2460) in Ds

+ π0γ, Ds +γ , Ds + π+π–

Experimentally well established Nature unclear: 4q states, molecules?

• L. Schmitt, GSI

Baryon Spectroscopy

Hadron 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

• L. Schmitt, GSI

Exotic Hadrons

Hadron Spectroscopy

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

• L. Schmitt, GSI

Exotic Hadrons

Hadron Spectroscopy

Charm Spectroscopy

Charm quark: m c >> m u,d,s

➔ Perturbative to strong coupling

Charm Hybrids

c-states narrow, understood Little interference of ccg & cc-states Mass 4–4.5 GeV, c c g narrow, ~ σ( p p → c c)

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

• L. Schmitt, GSI

Hadron S adron Structure tructure

• 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:

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

Expt.

Hadron Structure

• L. Schmitt, GSI

Generalized Parton Distributions

Properties of GPDs: Properties of GPDs:

GPDs carry information on GPDs carry information on longitudinal longitudinal and and transverse transverse distribution of partons distribution of partons GPDs contain also information on quark GPDs contain also information on quark (orbital) angular momentum (orbital) angular momentum H(x,0,0) = q(x) structure functions of DIS H(x,0,0) = q(x) structure functions of DIS ∫ ∫H(x,0,t) dx = F(t) nucleon formfactor H(x,0,t) dx = F(t) nucleon formfactor GPD GPD

x+ξ x-ξ

Handbag Diagram What GPDs are: What GPDs are:

A fractional momentum A fractional momentum ξ ξ is taken out is taken out GPDs: 4 functions H(x, GPDs: 4 functions H(x,ξ,t ξ,t), E(x, ), E(x,ξ,t ξ,t), ), ~ ~ ~ ~ H(x, H(x,ξ,t ξ,t), E(x, ), E(x,ξ,t ξ,t) (polarized) ) (polarized)

Quark distribution q(x), -q(-x)

• M. Vanderhaeghen

Hadron Structure

• L. Schmitt, GSI

GPDs in PANDA

Generalized Parton Distributions

Deeply virtual Compton scattering Hard exclusive meson production Crossed channels with p Wide angle Compton scattering Hard exclusive meson production Simulation Signal: pp→γγ Backgrounds: pp→γπ0, pp→π0 π0

GDAs GDAs

Meson p p p p

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

p p e,µ e,µ

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, q2<0 Annihilation: timelike FF q2>4 M p

2

Hadron Structure

• L. Schmitt, GSI

Out utlo look:

• k: Beyond P

Beyond PAND ANDA

• 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

Polarised proton beam:

Mid-term option using snake in HESR: a preparation to ENC or PAX

BESS-Polar ultra thin solenoid (1 g/cm2 Al/Nb, 0.11 X0) as model for the counter solenoid

Outlook: Beyond PANDA

• L. Schmitt, GSI

Electron Nucleon Collider

Outlook: Beyond PANDA

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

• L. Schmitt, GSI

Polarized Antiprotons in PAX

Outlook: Beyond PANDA

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

• 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