H. Koch, SFAIR, Lund, Sept. 12-13, 2005 Hadron Physics with Antiprotons Overview Physics with Antiprotons @ PANDA (see J. Ritman, U. Wiedner) – Hadron

H. Koch, SFAIR, Lund, Sept. 12-13, 2005

Hadron Physics with Antiprotons

Overview

Physics with Antiprotons @ PANDA (see J. Ritman, U. Wiedner)

– Hadron Spectroscopy

– Properties of Hadrons in Matter

– Double -Hypernuclei

– Options

Conclusions


Overview on p-induced Reactions

High Energy: pp-Colliders (CERN, Fermilab)

Discovery of Z0, W±

Discovery of t-Quark

Medium Energy: Conventional p-beams (LBL, BNL, CERN, Fermilab, KEK, ...) p-Storage Rings (LEAR (CERN); Antiproton Accumulator (Fermilab))

p-N interactionMeson Spectroscopy (u, d, s, c)p-nucleus InteractionHypernucleiAntihydrogen

Low Energy (Stopped p‘s): Conventional p-beams p-Storage Rings (LEAR, AD (CERN))

p-Atoms (pHe)p/p-mass ratioAntihydrogen

FAIR-Project

Higher p-energies (≤ 15 GeV)Cooled p-beamsMuch higher luminosities


UNILACSIS

FRS

ESR

SIS 100/300

HESRSuperFRS

NESR

CR

RESR

ExistingExisting

Future ProjectFuture Project

PANDA

PAX

FLAIR

CBM



Hadron Spectroscopy

Naive Quark Model: Mesons (Resonances) = qq-states Baryons (Resonances) = qqq-states

Particular states: cc = Charmonium (QCD-analog to e+e–-Positronium states)

LQCD + Model calculations: Existence of exotic states

New feature: Spin-exotic quantum numbers possible, not allowed in qq (JPC = 0+–, 1–+, ...)


Charmonium – the Positronium of QCD

3D2

2900

3100

3300

3500

3700

3900

4100

c(3590)

c(2980)

hc(3525)

(3097)

(3686)

(3770)

(4040)

0(3415)

1(3510) 2(3556)

3D1

3D3

1D2

3P2(~ 3940)

3P1(~ 3880)

3P0(~ 3800)

(~ 3800)

1 fm

C C

Mass [MeV]

DD~ 600 meV

-1000

-3000

-5000

-700011S

0

13S1

21S0 23S

121P

1 23P2

23P1

23P0

031S

0 31D

2 33D2

33D1

33D2

Ionisationsenergie33S

1

e+ e-0.1 nm

Binding energy [meV]

8·10-4 eV

10-4 eV

Positronium Charmonium


cc(g) - Lattice Predictions

42] K. Juge, J. Kuti, and C. Morningstar, Phys. Rev. Lett. 90, 161601 (2003).


Glueballs

Self interaction between gluons

Construction of color-neutral hadrons with gluons possible

exotic glueballs don‘t mix withmesons (qq)

0--, 0+-, 1-+, 2+-, 3-+, ...

C. Morningstar PRD60, 034509 (1999)

gg

g

RG

GR

BGGRRB


PANDA – Hadron Spectroscopy Program

Mass range:



Experiments cc :

c (11S0)experimental error on M > 1 MeV hard to understand in simple quark models

c’ (21S0)

Crystal Ball result way offstudy of hadronic decays

hc(1P1)

Spin dependence of QQ potentialCompare to triplet P-StatesLQCD NRQCD

States above the DD thresholdHigher vector states not confirmed (3S), (4S) Expected location of 1st radial excitation of P wave statesExpected location of narrow D wave states, only (3770) seenSensitive to long range Spin-dependent potential

Nature of the new X(3872)/ X(3940), Y(3940) and Z(3940)

9

)(5)(3)( 210 MMMMcog

++=



Hybrids (ccg) :

?

Example: Ground State

Decay modes: ,

Decay modes: J/; D*D



Predictions:

Masses:

1.5-5.0 GeV/c2 (Ground state found? ;

Candidates for further states?)

Quantum numbers:

Several spin exotics (oddballs), e.g.

JPC = 2+- (4.3 GeV/c2 )

Widths: ≥ 100 MeV/c2

– Decay into two lighter glueballs often forbidden because of q.-n.

– No mixing effects for oddballs

Glueballs (gg)

Decays: , ,



Open Charm States

The DS± spectrum |cs> + c.c. was not

expected to reveal any surprises, but ...

– Potential model

– Old measurements

– New observations

(BaBar, CLEO-c, Belle)

Or these are molecules?

0− 1− 0+ 1+ 2+ 2−

D s

D s*

D sJ*

(2317)

D 1s

D 0K

D*K

D sJ(2458)

D 2s*

J P

New observations


Merits of Antiprotons (1)

Measured rate

Beam

Resonance cross

section

CM Energy

In pp-annihilation all mesons can be formed

Resolution of the mass and width is only limited by the (excellent) beam momentum resolution

Example: pp 1,2

J/ e+e–

In contrast: In e+e–-annihilation only JPC = 1-- can be found

e+e– J/ , e+e– 1,2



p-beams can be cooled Excellent beam momentum resolution

0.97 1 1.03

rel. ion velocity v/v0

before cooling

after cooling


High Resolution of M and

Crystal Ball: typical resolution ~ 10 MeV

Fermilab: 240 keV

PANDA: ~20 keV

Dp/p ~ 10-5 needed



pp-cross sections high Data with very high statisties

Example: pp 000 (LEAR) f0(1500) = best candidate for Glueball ground state

Low final state multiplicities: Clean spectra, Good for PWA analyses



High probability for production of exotic states

Example: pp 00 : (1400) (JPC = 1–+) = candidate for Hybrid ground state^


Properties of Hadrons in Matter

Mass splittings because charge conjugation symmetry broken at nB 0

Overall attraction of Kaons due to scalar interaction: KN sigma term

Mass splitting due to vector interaction: Weinberg-Tomozawa

c d_

d du

c_ d

repulsive

attractive

D-

D+d du

d du

d du

d du

d du

K– (su): ms/mu ≈ 40D+ (cd): mc/md ≈ 200 Quark atom


J/, Absorption in Nuclei

J/ absorption cross section in nuclear matter p + A J/ + (A–1)


Douple -Hypernuclei

Hypernuclei open a 3rd dimension (strangeness) in the nuclear chart Double-hypernuclei:

very little data

Baryon-baryon interactions: -N only short ranged (no 1 exchange due to isospin) impossible in scattering reactions

-

3 GeV/c

K+KTrigger

_

secondary target

p

-(dss) p(uud) (uds) (uds)

–

–


Timelike Proton Form Factors at large Q2

The time like FF remains about a factor 2 above the space like. These differences should vanish in pQCD, thus the asymptotic behavior has not yet been reached at these large values of |q2|. (HESR up to s ~ 25 GeV2)(PANDA probably up to 20 GeV2)

q2>0

q2<0


Physics Program / Further Options– Baryon Spectroscopy

New states, Quantum numbers and decay rates

€

Multi − Strangeness Channels Threshold GeV / c

2

[ ]p

LabGeV / c[ ] σ p p → B B

( )

Δ Δ 2 . 23 1 . 43 100 μ b

Λ Σ 2 . 31

Σ Σ 2 . 39 10 μ b

Λ Σ ( 1385 ) 2 . 50 2 . 20

Λ Λ ( 1405 ) 2 . 52

Λ Λ ( 1520 ) 2 . 64

Ξ Ξ 2 . 64 2 . 62 2 μ b

Ξ Ξ ( 1530 ) 2 . 85

Ω Ω 3 . 35 4 . 93 200 nb

Charmed Channels

Λc

Λ c

4 . 57 10 . 1 20 nb

Λc

Σ c

4 . 74 11 . 0

Σc

Σ c

4 . 91 11 . 9 10 nb

Ξc

Ξ c

4 . 93 12 . 0 0 . 1 nb

Ξc

*

Ξ c

*

5 . 33 14 . 1

Ωc

Ωc

5 . 33 14 . 1 0 . 1 nb


Physics Program / Further Options

Direct CP-Violation (SCS)

€

D0 /D 0 − Mixing(r)<10−8(SM) HESR: Δr/r ~10−4

€

CompareD+ → K +K 0* /D− → K −K 0* AsymmetriesA (SM)<10−3

HESR = ΔA /A ≈10−4 −10−3

– CP-Violation in charmed region

€

A ≈α+α α−α

– Direct CP-Violation in , -decays

Compare angular decay asymmetries

Prediction (SM) ≈ 2x10-5 HESR: 1 year of beamtime

€

(α,α ) for Λ → pπ−/Λ → p π+


Physics Program / Further Options

Study of reversed Deeply Virtual Compton Scattering (DVCS) Nucleon structure functions

€

p +p→ γ*+γ→ l +l −+γ


Conclusions

Enormous impact in particle physics of p-induced reactions

p-induced reactions have unique features

– Nearly all states can be directly produced

– High cross sections guarantee high statistics data

p-beams can be cooled very effectively

The planned p-experiments at FAIR will contribute to a further understanding of the non-perturbative sector of QCD


Charmonium Production in pp

* for selected decay mode

** L = 2x1032 cm–2s–1, 50% accelerator and detector efficiency, integrated luminosity = 8 pb–1/day

*** 1% B.R. for this decay mode


QCD-Vacuum as function of p and T


HESR / PANDA

Production Rates (1-2 (fb)-1/y)

Final State

€

Mesonresonance+anything 100μb 1010

ΛΛ 50μb 1010

Ξ Ξ (→ ΛΛ A) 2μb 108 (105)

DD 250nb 107

J /ψ (→ e+e– ,μ+μ– ) 630nb 109

χ2 (→ J /ψ+γ) 3.7nb 107

ΛcΛ c 20nb 107

ΩcΩ c 0.1nb 105

cross section # reconstr. events/y

Common Feature : Low multiplicity events Moderate particle energiesFor Pairs : Charge symmetric conditions Trigger on one, investigate the other


Charmonium Physics

DD

DD*

ψ(11D2) ψ(13D1)

ψ(13D3)

ψ(13D2)

ηc(21S0)

D*D*

ψ(23S1)

J/ψ(13S1)

ψ(33S1)

c2(13P2)

c0(13P0)

c1(13P1)h1c(11P1)

c0(23P0)c1(23P1)

c2(23P2)

h1c(21P1)

ηc(11S0)

ηc(31S0)

JP=0- 1- 1+ (0,1,2)+ 2- (1,2,3)-

Are (4040) and (4160) strong mixtures of the (3S) and hybrid charmonium states or (4040) is D*D*-molecule?

2.9

Mcc

[G

eV

/c2]

3.0

3.1

3.2

3.3

3.4

3.5

3.6

3.7

3.8

3.9

4.0

4.1

4.2

4.3

4.4

4.5

4.6

ψ(43S1)

X(3872)

DsJ*DsJ*

Is the narrow X(3872) state D0D* molecule?

Most states above DD not measured

Measure decay branching ratios. 3.4

4.1

4.8

5.5

6.3

7.1

8.0

9.3

10.3

Pla

b [GeV

/c]


Threshold production of DsJ(2317)*

Depend on internal structure the width of DsJ can be different:

– Current limit 4.9 MeV – -doubling 10 keV – Phenomenological 130 keV – DsK – molecules 200 keV

10 5−=ppδ

keVMM 20=δ

10 4−=ppδ

keVMM 200=δ

10 3−=ppδ

MeVMM 2=δ

*


Crypto-exotic Baryons with Charm ?

J.Hofmann & M.Lutz hep-ph/0507071

Many Narrow Resonances

Decays to N


HESR: High Energy Storage Ring

Beam Momentum 1.5 - 15 GeV/c

High Intensity Mode:Luminosity 2x1032 cm-2s-1 (2x107Hz)δp/p (st. cooling) ~10-4

High Resolution Mode:Luminosity 2x1031 cm-2s-1 δp/p (e- cooling) ~10-5

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

Documents

H. Koch, SFAIR, Lund, Sept. 12-13, 2005 Hadron Physics with Antiprotons Overview Physics with Antiprotons @ PANDA (see J. Ritman, U. Wiedner) – Hadron