effects of thermal partons on J/psi

1
Hadron spectroscopy, Heavy pentaquark, and B
decay
Su Houng Lee Yonsei Univ., Korea

1. Introduction
2. Theory survey
3. Charmed Pentaquark
4. Charmed Pentaquark from B decays

References H. Kim, Y. Oh, S.H.Lee, PLB 595
(04) 293 Y. Sarac,
H.Kim, S.H.Lee, PRD 73 (06) 014009
S.H.Lee, Y. Kown, Y. Kown, PRL 96
[phone]
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Exotics

• Hadrons that can not be expalined by
  quark-antiquark, or 3 quarks
• That are bound by strong interaction
• Reasons for its search are similar to that for
  superheavy Element

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Introduction
1. LEPS coll., Nakano et.al. PRL 91 012002 (2003)
Mass 1.54 GeV , width lt25 MeV , quark
content uudds
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Verification
2. Verification by other group
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3. CLAS finds no Q in K P invariant mass
? Q(udud s) belongs to anti-decuplet
5. Recent CLAS finds no Q in gamma d , gamma p
in K P invariant mass ? Q(udud s)
belongs to anti-decuplet
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Positive results
Negative results
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Baryon Reprsentation
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Heavy Pentaquarks (udud c)
1. H1 collaboration (Deep Inelastic scattering)
Qc(3099) was found in D p (uudd bar(c))
with width 12-3 MeV
2. Could not confirm in subsequent experiments
CDF, ZEUS, FOCUS
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Experimental summary
2. Qc controversial ? questionable search
was done with DN DN final state (unbound)
gt 2800 MeV e
3. Give up, more experiment or theoretical
guideline?
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Theory review

• Soliton model Quark model
• (biased and limited)

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Soliton model original prediction (Diakanov,
Petrov, Polyakov 97)
1. SU(3) soliton
IJ Hedghog
2. Quantizing the 8 angles, the Hamiltonian
becomes
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3. With constraint coming from WZ term

• 1. only SU(3) representations containing Y1
  are allowed
• moreover, the number of states 2I1 at S0 or Y
  Nc/3 must determine the spin of the
  representation through 2J1 because IJ in the
  SU(2) soliton
• ? one spin state for given representation

4. Diakanov Petrov Polyakov applied it to Anti
decuplet which predicted mass 1540, width30
MeV
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Quark models
Negative parity if all the quarks are in the
lowest s-state
But with this simple picture, it is not easy to
understand small width
Positive parity if a relative p wave

• Karlinear, Lipkin
• diquark C3,F3,S0
• triquark C3,F6,S1/2

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Positive parity if a relative p wave
2. Jaffe, Wilczek
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But, a closer look revealed puzzles
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Naive Solition model should fail (T. Cohen)
1. Soliton picture is valid at large
N_c Semi-classical quantization is valid for
slow rotation ie. Valid for describing
excitations of order 1/N_c, so that it does not
mix and breakdown with vibrational modes of order
1
2. Lowest representation SU(3)f (p,q) at large N_c
Quantization constraint requires

• Octet
• Decuplet
• Anti decuplet
• (lowest representation containing s1)

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3. Mass splitting in large N_c
Anit decuplet octet mass splitting is mixes with
vibrational mode and inconsistent with original
assumption and has undetermined correction of
same order ? Rotation is too fast and may couple
to vibrational modes, which might be important to
excite q qbar mode, hence describing anti
decuplet state with naive soliton quantization
might be wrong
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Bound state approach for SU(3) soliton
1. SU(2) soliton Kaon
2. Successful for hyperon (attractive (s qbar) )
but no pentaquark (repulsive q sbar) from WZ term
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Summary of Solition approach for Q (ududs)
1. SU(3) Soliton Inconsistent application
Can not be applied to heavy pentaquark Qc(ududc)
2. Bound state approach No bound Q
predict a bound heavy pentaquark Qc(ududc)
ie. mass is smaller than DN continuum
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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
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Why Heavy Pentaquark
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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
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Y. Sarac, H. Kim, S. H.Lee (PRD 05)
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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
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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
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Color spin interaction explains hadron spectrum
Nucleon
Baryon Mass difference
Meson Mass difference
Works very well with 3CBCM constant
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Why there should be a heavy pentaquark
1. For a Pentaquark
L0 L1
2. If recombined into a Kaon and a Nucleon
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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?
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Anti-Charmed pentaquark from B decays
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Baryonic decay mode of B
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Baryonic decay mode of B
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Pentaquark decay mode of B
Using pevious fit, we find the branching
ratio to be 14.4x10-7
gDpL x gKpQ/gKpL
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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
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References

• Experiments
• T. Nakano , Phys. Rev. Lett. 91 (03) 012002.
• K.H.Hicks, Prog. Part. Nucl. Phys. 55 (05)
  647.
• Skyrme model controversy
• T.D.Cohen, Phys. Lett. B 581 (04) 175
• H. Walliser and H. Weigel, Eur. Phys. J. A
  26 (05) 361.
• D.Diakonov, V.Petrov and M.V.Polyakov, Z.
  Phys.A 359 (97) 305
• Theory
• H. J. Lipkin, Phys. Lett. B 195 (87) 484.
• Fl. Stancu, Phys. Rev. D 58 (98) 111501.
• D. O. Riska, N. N. Scoccola, Phys. Lett. B 299
  (93) 338.
• Y.Oh, B.Y. Park, D.P. Min, Phys. Lett. B 331
  (94) 362. Phys. Rev. D 50 (94) 3350.
• R.L.Jaffe, F.Wilczek, Phys. Rev.Lett. 91(2003)
  232003.
• present work
• H. Kim, Y. Oh, S.H.Lee, PLB 595 (04) 293
  
• Y. Sarac, H.Kim, S.H.Lee, PRD 73 (06) 014009