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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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
UNILACSIS
FRS
ESR
SIS 100/300
HESRSuperFRS
NESR
CR
RESR
ExistingExisting
Future ProjectFuture Project
PANDA
PAX
FLAIR
CBM
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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–+, ...)
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
cc(g) - Lattice Predictions
42] K. Juge, J. Kuti, and C. Morningstar, Phys. Rev. Lett. 90, 161601 (2003).
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
PANDA – Hadron Spectroscopy Program
Mass range:
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
PANDA – Hadron Spectroscopy Program
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
++=
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
PANDA – Hadron Spectroscopy Program
Hybrids (ccg) :
?
Example: Ground State
Decay modes: ,
Decay modes: J/; D*D
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
PANDA – Hadron Spectroscopy Program
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: , ,
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
PANDA – Hadron Spectroscopy Program
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
Merits of Antiprotons (2)
p-beams can be cooled Excellent beam momentum resolution
0.97 1 1.03
rel. ion velocity v/v0
before cooling
after cooling
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
High Resolution of M and
Crystal Ball: typical resolution ~ 10 MeV
Fermilab: 240 keV
PANDA: ~20 keV
Dp/p ~ 10-5 needed
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
Merits of Antiprotons (3)
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
Merits of Antiprotons (4)
High probability for production of exotic states
Example: pp 00 : (1400) (JPC = 1–+) = candidate for Hybrid ground state^
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
J/, Absorption in Nuclei
J/ absorption cross section in nuclear matter p + A J/ + (A–1)
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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)
–
–
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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+
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
Physics Program / Further Options
Study of reversed Deeply Virtual Compton Scattering (DVCS) Nucleon structure functions
€
p +p→ γ*+γ→ l +l −+γ
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
QCD-Vacuum as function of p and T
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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]
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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
*
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
Crypto-exotic Baryons with Charm ?
J.Hofmann & M.Lutz hep-ph/0507071
Many Narrow Resonances
Decays to N
H. Koch, SFAIR, Lund, Sept. 12-13, 2005
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