Multiquark states by a quark model

Transcription

1 Multiquark states by a quark model Sachiko Takeuchi (Japan Colledge of Social Work) with M.Takizawa (Showa Pharm U) K.Shimizu (Sophia U) S.Fukino (TITech) M.Oka (TITech) M. Takizawa and S. T., PTEP 2013, 0903D01 (2013) S.T., K. Shimizu, M. Takizawa, PTEP 2014, 0903D01 (2014)

2 Theories and models QCD pqcd Lattice QCD NonRela QCD Hadron models Quark models Quark models with light mesons 2

3 Theories and models QCD pqcd flavor sym chiral sym Lattice QCD NonRela QCD Hadron models color spin sym Heavy mq sym Quark models Quark models with light mesons 3

4 Theories and models QCD effective q mass hadron masses pqcd Lattice QCD NonRela QCD hadron int Hadron models qq or qq int Quark models Quark models with light mesons 4

5 Theories and models stars nuclei QCD production rate Qnuclei decay width resonances radiative decay pqcd Lattice QCD NonRela QCD exotic hadrons Hadron models hadrons Quark models Quark models with light mesons 6

6 Theories and models Qnuclei Hadron models exotic hadrons resonances production rate decay width trans op radiative decay multi channel hadron int pqcd Quark models with light mesons Lattice QCD NonRela QCD effective q mass qq or qq int Quark models 7

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8 configurations for qqq qqbar hadrons gr state hadrons can be classified by the sym. PDG 9

9 qq, qqbar int Confinement + colorcoulomb Godfrey Isgur, PRD32, 189 (1985) 10

10 hyperfine interaction V_color magnetic Not a Casimir op for the q n (q ) n! One has to be careful when evaluate it in the multiquark states. 11

11 quark effects found in the multiquark Quark Pauliblocking configurations for multiquarks N <qq... A qq...> 1 (in general)! N>1 attractive, N<1 repulsive color magnetic interaction repulsive in NN(3S1,1S0) attractive in H etc channel coupling quark rearrangement 12

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13 `Multiquark states qq qq qq meson twomesons coupled channels qqq qqqqq baryon meson cloud coupled channels qqqqqq BB = NN, YN! (S, Pwave) consistent with LQCD qualitatively qq qq, qqqqq pure exotic states How important the quark modes? 14

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15 YcN potential from CMI (local part) Vlocal MeV Pauliblocking repulsion cn IJ 3 2,1 cn IJ 3 2,0 cn IJ 1 2, Pauliblocking repulsion ΣN threshold cusp? cn IJ 1 2,0 cn IJ 1 2,1 Vlocal MeV R fm ΛcN (1/2,0) [=(1/2,1)] CMI (local+nonlocal) by q 6 150MeV as mq 200 c b heavy quark limit R fm S Fukino, Master Thesis

16 YcN potential (nonlocal part) Λc N (IJ=1/2 0) 17

17 YcN potential (nonlocal part) Λc N (IJ=1/2 1) 18

18 Quark part gives an repulsion for ΛcN Repulsive in the local part of the potential weakly attractive + repulsive in the nonlocal part of the potential No Pauliblocking repulsion in these channels. Pauliblocking repulsion ΣcN IJ=(1/2 0) and (3/2 1) No Pauliblocking for ΣcN IJ=(1/2 1) 19

19 ΔΔ(S=3,I=0) attractive?! <ΔΔ CMI ΔΔ>2<Δ CMI Δ> < 0 CMI is repulsive in Δ PRL102, (2009) 20

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21 1 B B B + K + + J/ψ + ππ(π) B + X(3872) K + 22 b c W X(3872) u s c K " " J/ψ ρ or ω π n b c " W X(3872) " u s c K ρ,ω D D* J/ψ ππ(π) J/ψ π 2 Exp: S.K.Choi et al. [Belle] PRL91, (2003) B.Aubert et al. [BaBar] PRD71, (2005) D D * D 0 D * 0 exp T.Aushev et al. [Belle] PRD81, (2010) B.Aubert et al. [BaBar] PRD77, (2008) M. Takizawa and S. T., PTEP 2013, 0903D01 (2013) S.T., K. Shimizu, M. Takizawa, PTEP 2014, 0903D01 (2014)

22 1 ++ Spectrum of cc E X(3872) χ c1 (1P) n=5 n=4 n=3 n=2 n=1 Exp. QM( 3 P 1 ) E DsD s*, J/ψ DD *, J/ψV n=2 D + D*, J/ψω X(3872) D 0 D * 0, J/ψρ Exp. QM( 3 P 1 ) 0 23

23 1 ++ Spectrum of cc E X(3872) χ c1 (1P) n=5 n=4 n=3 n=2 n=1 Exp. QM( 3 P 1 ) Quark Model DsD s*, J/ψ DD *, J/ψω, J/ψρ Im(E) Re(E) x x x x x x x x x x Couplings to two hadrons 1 24

24 Roles of the quark mode in X(3872) ccbar mass & potential 3 P 1 spectrum (the first two states) ccbar DDbar coupling large ambiguity the size can be estimated from the isospin sym breaking measurements DDbarJ/ψω, J/ψρ couplings large ambiguity rough size can be evaluated from the quark rearrangement constraints from experiments 25

25 Charged qqq bar q bar states Zc(4430) + ψ(2s)π M = 4475± MeV, Γ = 172± MeV nearby threshold: DD bar 2*?? Zc(3900) + J/ψπ, DD bar * M = ±3.4 MeV, Γ = 35±7 MeV nearby threshold: DD bar *?? And so on... The coupling to the ψπ channel should be somehow small to form a resonance. X(3872), suppressed because of the Cparity. 26

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27 Λ(1405)1/2 and Λ(1520)3/2 Quark model picture Λ 1 (flavor siglet) pole + Σπ + NK bar (+ Λη + ΞK) attraction is in Σπ, not in NK bar large mixing between Σπ and NK bar coupling to BM channel pushes down the Λ 1 pole by 80MeV.! large mass difference between Λ(1405) and Λ(1520) S Takeuchi and K Shimizu, PRC76, (2007) 28

28 QCM calc S Takeuchi and K Shimizu, PRC76, (2007) 29

29 QCM calc S Takeuchi and K Shimizu, PRC76, (2007) 30

30 Pentaquark uddcc bar Relevant? hadrons Λc(1/2+)" ±0.14 MeV Σc(2455) + (1/2+)" ±0.4 MeV" Σc(2520) + (3/2+)" ±2.3 MeV" Γ < 4.6 MeV Γ < 17 MeV D bar *(2007) 0 (1)" ±0.10 MeV"Γ 2.1 MeV D bar0 (0)" J/ψ(1)" p(1/2+)" MeV MeV MeV q q Q q q q q Q bar Q Q bar 31

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32 Pentaquark Pc + (4380) Pc + (4450) First try... JP=3/2 Relative Swave threshold energy Σc*+D bar *" MeV Σc+D bar *" MeV Σc*+D bar " MeV Λc+D bar *" MeV p+j/ψ " MeV q q q q q Q Q Q bar q Q bar 33

33 Pentaquark Pc + (4380) Pc + (4450) Quark model (0s) 5 Norm" " p+j/ψ Λc+D bar * Σc+D bar * Σc*+D bar Σc*+D bar * very very preliminary 34

34 Pentaquark Pc + (4380) Pc + (4450) Quark model (0s) 5 CMI (MeV)"" p+j/ψ Λc+D bar * Σc+D bar * Σc*+D bar Σc*+D bar * very very preliminary 35

35 Summary Quark mode can be seen in multiquark systems as Pauliblocking repulsion (attraction) CMI repulsion and attraction qqqqqc small b for cquark can be calculated ΛcN IJ=1/2(0) mild repulsion qqbarqqbar X(3872) can be understood as a hadron molecule with a ccbar core. 36

36 Summary qqqqqbar Λ(1405) has a core?! As a starting point of Λ as mq, the quark picture must be taken, which, at least at a glance, is very different from the chiral unitary picture. Pc! (simple) scattering systems can be calculated.! there may be a channel(s) which couples to J/ψ p channel only very weakly?? 37

37 Thank you very much for your attention! 38