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How BaBar can decide what charmonium-like states 4260, 4360…. really are. The accidental discovery of a new spectroscopy?. Work by FC with Clark Downum (in PRL) and Chris Thomas (preliminary). 4 to 4.5 GeV region. Gluonic charmonium (hybrid) predicted couples to DD1 and D*D0.
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How BaBar can decide what charmonium-like states 4260, 4360…. really are The accidental discovery of a new spectroscopy? Work by FC with Clark Downum (in PRL) and Chris Thomas (preliminary)
4 to 4.5 GeV region Gluonic charmonium (hybrid) predicted couples to DD1 and D*D0 Strong attractive forces between D* D1 also between DD1 and D*D0 And enigmatic state(s) observed in expt How BaBar can resolve the dynamics ! 2
DD* 1++(3872) DD1 1--(4260) D*D1 JPC?(4430) 1- - (4360) psiprime pipi I=1 !? D*D1 17 3
DD* 1++(3872) DD1 1--(4260) D*D1 JPC?(4430) 1- - (4360) psiprime pipi I=1 !? D*D1 all are S wave in s-channel! 17 4
Why are nuclear binding energies \sim O(1) MeV per nucleon ? 5
Why are nuclear binding energies \sim O(1) MeV per nucleon ? Pi exchange is in P-wave= penalty 6
Why are nuclear binding energies \sim O(1) MeV per nucleon ? Pi exchange is in P-wave= penalty What if Pi exchange is in S-wave= no penalty => binding energies \sim O(100) MeV per hadron 7
Why are nuclear binding energies \sim O(1) MeV per nucleon ? Pi exchange is in P-wave= penalty What if Pi exchange is in S-wave= no penalty => binding energies \sim O(100) MeV per hadron Can happen for D1 => D* pi in S wave 8
Why are nuclear binding energies \sim O(1) MeV per nucleon ? Pi exchange is in P-wave= penalty What if Pi exchange is in S-wave= no penalty => binding energies \sim O(100) MeV per hadron Can happen for D1 => D* pi in S wave • D1D* deep bound molecules • And in S-wave = 1^{- -} • Examples 4260; 4360 ….. 9
DD* 1++(3872) D*D1 1--(4260) D*D1 JPC?(4430) 1- - (4360) psiprime pipi I=1 !? D*D1 all are S wave in s-channel! 17
gluonic degrees-of-freedom R Costs about 1 to 1.5GeV energy to excite phonon “pi/R” Hybrid qq* @ 2GeV; Hybrid cc* @ 4-4.5GeV Barnes FC Swanson 93 11
Predicted 1-+ Hybrid masses (with spin splittings) charmonium
Predicted 1-+ Hybrid masses (with spin splittings) charmonium Near D(L=0)+D(L=1) thresholds: DD0; DD1; D*D0;D*D1 and strongly coupled to these channels …..how distinguish hybrid from DD1 etc molecules?
Predicted 1-+ Hybrid masses (with spin splittings) Spin hyperfine splittings 1- - (4.25) Y(4260?) 1- + (4.1) HQLGT 0- + (3.95) X(3940?) Barnes FC 82 Chanowitz Sharpe e+e- feebly coupled e+e- \to \psi + X? 14
e+e- to + X Novel states in ??? 0-+;1-+ 15
e+e- \to psi pi pi BaBar sees unusual vector cc* \Gamma(ee) 5-80eV Compare \sim 1 keV !! psi pipi violate OZI But width 90MeV typical hadron ! psi D Y(4260) D_1 uu * pi pi 16
Beyond Spectroscopy To do more need dynamics: Production; decays; selection rules Lattice hints about dynamics Hybrids and DD1 decays 17 35/18
What properties Lattice S-wave decays now calculatedMichael McNeile confirms Flux Tube for hybrid:conventional Michael McNeile 06 FC Burns 06 Exactly WHAT is Lattice revealing about dynamics: What significance if ratio \sim 2? 18
qq* create in S=1 2 qq* create in S=0 0 19
J – S = “L” Factorisation of S and L qq* created in S=1 Factorisation and S=1 creation is powerful result if generally true. Determine nature of Y(4260) by DD_1 pattern 20
SL Factorisation and S=1 selection rules for psi*(cc*) \to DD_1 Also applies to KK_1 decays of ss* vectors e.g. ISR around 2.2 GeV 21
4260 decays…. …using strong selection rules to distinguish candidates… Conventional charmonium Hybrid charmonium Tetraquark csc*s*; Charm molecule D*D1 or DD1 22
e.g. p=1 c.m. flux-tube breaking and hybrid decays Isgur Paton 92 light exotics FC Page 95 all Break tube: S+P states yes; S+S suppressed Look for DD_1 and D*D_0near threshold Absence of DD; DD*; DsDs … 24
Y(4260): D_s and D_s* channels No DsDs resonance eliminates tetraquark csc*s* 25
Y(4260): D and D* channels No DD DD* or D*D* resonance 25
All consistent with predictions for hybrid charmonium FC+Page 1995 Search DD_1 and D*D_0 in DD\pi\pi If NOT hybrid cc* then why not/where is it ?! 27
The large psi +pi pi= hint of large D(*)D1 e+e- psi(hybrid) D(*)D_1 S-wave, relative mom \sim 0; DD_1 interchange constituents to make psi pipi “strongly” psi D D_1 uu * pi pi 28
The large psi +pi pi= hint of large D(*)D1 e+e- psi(hybrid) D(*)D_1 S-wave, relative mom \sim 0; DD_1 interchange constituents to make psi pipi “strongly” psi D D_1 uu * pi pi Problem: Heavy cc* preserve their spin. Psi has cc* with S=1 Hybrid has cc* with S=0 (h1c eta or etac omega ?) Problem: and other states: 4360;4430… 28
Hybrid affected by thresholds Attractive force from pi exchange: 4260 a result of D1D* (!!) threshold: look for e+e- \to DDbar + 3pi And what about 4360 in psiprime pipi and 4430 in psiprime pi …..???? 29
The Answer: A new spectroscopy? • At least…..something unexpected! • 1++(3872) DD* via \pi exchange in p-wave • 1– (4260 etc) D1D* via \pi exchange ……… 30
The Answer: A new spectroscopy? • At least…..something unexpected! • 1++(3872) DD* via \pi exchange in p-wave • 1– (4260 etc) D1D* via \pi exchange in s-wave! 31
N N pi: deuteron; O(1 MeV) D* to D pi (P wave) O(q^2) DD* to D*D binding O(1 MeV) X(3872) 32
N N pi: deuteron; O(1 MeV) D* to D pi (P wave) O(q^2) DD* to D*D binding O(1 MeV) X(3872) 1++(3872) DD* 32
N N pi: deuteron; O(1 MeV) D* to D pi (P wave) O(q^2) DD* to D*D binding O(1 MeV) X(3872) D1 to D* pi (S wave) O(mA-mB)^2 D1 D* binding O(100 MeV) M = D*D1(4440) - O(100MeV) 4260; 4360 ?? 33
Look at I=1 D1D* 1^{--} S wave pi exchange Find it does NOT bind 34
I=1 feeble binding if any Z(4430) Liu et al PRD77 034003 35
I=1 feeble binding if any Z(4430) Liu et al PRD77 034003 I=0 strong binding 36
Binding Energy: variational wfns 37 Radial excitation bound also?? Ground state B.E can be 100-200 MeV !!
Psi(1S)pipi (4260) Psi(2S)pipi (4360) and (?) 4600 38
D*D1 spectroscopy 4430 I=1 D*D1 threshold Potential is similar to Coulomb 4360 2S 1P 4350 4260 1S 39
Vector D*D1 spectroscopy 4430 I=1 D*D1 threshold 4360 2S cc* psi D* D_1 uu * pi pi 4260 1S 40
Vector D*D1 spectroscopy 4430 I=1 D*D1 threshold 4360 2S cc* psi D* (1S; 2S) 1S; 2S D_1 uu * pi pi 4260 1S 41
Vector D*D1 spectroscopy 4430 I=1 D*D1 threshold 4360 2S Psi(2S) pi pi 4260 1S Psi(1S) pi pi 42
Vector D*D1 spectroscopy 4430 I=1 D*D1 threshold 4360 2S Psi(2S) pi pi 4260 1S Psi(1S) pi pi DD pi pi pi 43
Phys Rev Letters (in press) The immediate test is 4260 decay to Then look for other exotica. Also in Bottomonium and strangeonium 44
Since PRL: (n.b. preliminary - not yet guaranteed) Sensitivity to D1 and D0 widths for pointlike mesons (value of h) Effect of finite D meson size (h function of momentum) Effect of extended pion (Lambda) And discovery of DD1/D*D0 molecules too: including exotic J(PC)=1(-+) 45
D and pipointlike: h=1 3800 h^2 width of D_1 to D^* \pi h=0.9 4050 Data: h \sim 0.7 – 0.8 h=0.8 4250 h=0.7 4350
Pion size (Lambda) Bad news Reduces BE: Extended pion provides smaller force BE tends to zero.
Pion size (Lambda) Bad news Reduces BE: Extended pion provides smaller force BE tends to zero. Good news • Finite D size: • h(q) => h(0) increases to > 1 • Scale of BE increases