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BARYONS 2013 International Conference On The Structure of Baryons Glasgow, June 2013. HEAVY QUARKONIA DESCRIPTION FROM AN ENERGY DEPENDENT POTENTIAL P. González Universitat de València and IFIC (SPAIN). 12 New Neutral Charmonium States since PDG 2000 - PowerPoint PPT Presentation
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BARYONS 2013
International Conference On The Structure of Baryons
Glasgow, June 2013
HEAVY QUARKONIA DESCRIPTION
FROM AN
ENERGY DEPENDENT POTENTIAL
P. González Universitat de València and IFIC (SPAIN)
12 New Neutral Charmonium States
since PDG 2000
9 X States (7 + 2 ? Unconventional)
J. Beringer et al. (PDG)PRD 86, 010001 (2012)
Conventional States
S. Godfrey, N. Isgur PRD 32, 189 (1985)
X states : Close-below or Above their First S-wave M-M Threshold
2 8 0 0
3 0 0 0
3 2 0 0
3 4 0 0
3 6 0 0
3 8 0 0
4 0 0 0
4 2 0 0
4 4 0 0
4 6 0 0
E (
MeV
)
0 + 1 -- J + + 1 +
X(3940)
D*D*| S(2++)
X(4140-60)
X(4350)
DD1|S, DD1|S
X(4260)
X(4360)D*D*
0|S
X(4660)
X(3915)
Unconventional States
Decay properties very different from conventionally expected
Conventional description: with parallel properties to
However decay properties completely different
Conventional description: or
However aan order of magnitude higher than expected
What are they ?
Quark-Antiquark effective (screened) potential States ?
Molecular Sates ?
Tetraquarks (compact states) ?
Quark-Antiquark + Molecular States ?
Hybrid (Quark-Antiquark + Gluon) States ?
Can we explicitly implement threshold effects
within a quark-antiquark model framework?
INDEX
i) Quenched versus Threshold-Unquenched Quark-Antiquark Ground
State Energy from Latttice.
ii) Quark Model Static Approach: Cornell Potential versus Energy Dependent Potential. Extended Quark Model.
iii) Heavy Quarkonia Description.
iv) Summary.
Quenched vs Threshold-Unquenched Quark-Antiquark GSE
G. S. Bali, Phis. Rep. 343,1 (2001)
G. S. Bali et al., PRD 71, 11453 (2005)
Extended Quark Model (EQM) : Energy Dependent Potential
Heavy Quarkonia Description
The lowest lying spectrum is described by the Cornell potential
Calculated masses differing at most 30 MeV (60 MeV) for bottomonium (charmonium).
Threshold Effects
Additional states + Attraction
results from the attraction produced by on the Cornell state
Additional states + Attraction
EQM : Non Overlapping Thresholds
The threshold has no effect below and above
Effective Thresholds (ET)
When two or more thresholds are almost degenerate there are overlapping effects which can be implemented through ET.
and are Interthreshold States
EQM Spectrum
2 8 0 0
3 0 0 0
3 2 0 0
3 4 0 0
3 6 0 0
3 8 0 0
4 0 0 0
4 2 0 0
4 4 0 0
4 6 0 0
E (
MeV
)
0 + 1 -- J + + 1 +
X(3940)
D*D*| S(2++)
X(4350)
DD1|S, DD1|S
X(4260)
X(4360)D*D*
0|S
X(4660)
X(4140-60)
X(3915)
EQM Spectrum
BB1
BB (0++)
BB* (1++)B*B* (2++)
S. Godfrey, N. Isgur PRD 32, 189 (1985)
EQM Eigenstates
Eigenstates from different energy regions are not orthogonal
Generator States
DD*|S(1++)
results from the attraction produced by on the Cornell state
Generator Potential :
results from the attraction produced by on the Generator state
Strong Decays
The Generator-Threshold Approximation
Assumption: The decay takes place, through light quark-antiquark creation, via the virtual generator-threshold state
Cornell Threshold
In general
Generator Threshold
Conventional Decay Mechanisms
Summary
i) There is a puzzle concerning experimentally unexpected charmonium states.
ii) There is a plausible universal explanation for this puzzle based on an Energy Dependent Potential (EDP) resulting from threshold effects.
iii) The Extended Quark Model (EQM) corresponding to this EDP may allow for a general description of hadrons (mesons and baryons) once spin dependent and other relativistic corrections are implemented.
Examples
Mesons:
S. Capstick, N. Isgur PRD 34, 2809 (1986)
Baryons:
Meson-baryon Thresholds:
Generator - Threshold Approximation
Consider a system of 1 confined channel (3q) in interaction with 1 free channel (meson-baryon).
Hamiltonian Matrix:
with
The couple channel solutions correspond to the eigenvalues of :
With a = 75 MeV all the anomalous masses can be reproduced within their experimental error bars.
P. Gonzalez, J. Vijande, A. Valcarce , PRC 77, 065213 (2008)
THE END
Unquenched Lattice-QCD ab initio calculation
A. Bazavov et al. (MILC)Rev Mod. Phys. 82, 1349 (2010)
We expect the short range part of the wave function to be only changed by normalization: