effects of thermal partons on Jpsi

1
Anti-Charmed Pentaquark from B decay
Su Houng Lee Yonsei Univ., Korea

• Why Heavy Pentaquark?
• Baryonic decay modes of B
• Anti-Charmed Pentaquark from B decays

2
Experimental search for Heavy Pentaquarks (udud
c)
1. H1 collaboration in 2004 (Deep Inelastic
scattering)
Qc(3099) was found in D p with width
12-3 MeV
D p (2950)
D p (2810)
2. Could not confirm in subsequent experiments
CDF, ZEUS, FOCUS in 2004, 2005
3
Why Heavy Pentaquark
4
Solition approach for light pentaquark Q (ududs)
1. SU(3) Soliton approach for Q controvery
T. Cohen Inconsistent application of large Nc
vs. Diakanov, ..
Can not be applied to heavy pentaquark Qc(ududc)
2. Bound state approach No bound Q
discussions between T. Cohen and Wiegel
predict a bound heavy pentaquark Qc(ududc) .
ie. mass is smaller than DN continuum
Quark model also predict a bound heavy
pentaquark Qc(ududc) but no light pentaquark
Q(ududs)
QCD sum rules also predict a bound heavy
pentaquark Qc(ududc) , Y. Sarac, H. Kim, SHLee
PRD 06
5
Possible Quark structure of a pentaquark
Karlinear, Lipkin model
diquark C3,F3,S0 triquark C3,F6,S1/2
Jaffe, Wilczek model
u
d
2 diquark C3,F3,S0 relative p wave
s
d
u
6
Color Spin Interaction in QCD
1. In QCD q-q are also attractive if in color
anti-triplet channel.
In perturbative QCD, 2CBCM This term is called
color spin interaction
7
Color spin interaction explains hadron spectrum
Nucleon
Baryon Mass difference
Meson Mass difference
Works very well with 3CBCM constant
8
Why there should be a heavy pentaquark
1. For a Pentaquark
L0 L1
2. If recombined into a Kaon and a Nucleon
9
Summary of Theory for Pentaquark
1. While there are some controversy over light
pentaquark, Soliton approach predict stable
heavy pentaquark
2. Constituent quark model also seem to predict
only heavy pentaquark
Could not observe heavy pentaqurk from DN final
state because it might be bound
Heavy pentaquark can only be observed from Weak
decay
May be from B factory? But do we have
sufficient data and can one conclude anything if
one tries?
10
Anti-Charmed pentaquark from B decays
11
Baryonic decay mode of B
12
Baryonic decay mode of B
13
Pentaquark decay mode of B
14
Summary

• While controvery exist over light pentaquark,
  Many Theories consistently predict bound heavy
  pentaquark

2. Baryonic decay mode of B can be sensibly
estimated with previously determined hadronic
parameters