新强子态 New types of hadrons 高能所 北京 Stephen Olsen & 夏威夷 大学 & 高能所 北京 新强子态 New types of hadrons HEP10 南京大学 April 26, 2008

Constituent Quark Model (CQM) Gell-Mann (& 6 antiquarks) 6 quarks Zweig u-2/3 c-2/3 t-2/3 u+2/3 c+2/3 t+2/3 b+1/3 s+1/3 d-1/3 s-1/3 b-1/3 d+1/3 Baryons: qqq Mesons: q q u+2/3 u+2/3 p: u+2/3 d-1/3 p+ : d+1//3 u-2/3 U-2/3 u-2/3 p: p- : D+1/3 d-1/3

Fabulously successful mesons q q

QCD suggests non-qq meson spectroscopies glueball

Charmonium model predictions for cc mesons are robust & reliable, both for masses & transition rates. Therefore, it is an especially good system to use to search for non-qq mesons.

predicted measured

agree with predictions About 20 measured transition rates D1D D(*)D(*) DsDs D(*)D(*) DsDs DD g g DD p0 pp g pp,h,p0 measured rates all agree with predictions (more-or-less) g g g

About 20 measured transition rates D1D D(*)D(*) DsDs D(*)D(*) DsDs DD g g DD p0 pp g pp,h,p0 G(pp-allowed) 50~ 100keV G(p – ispin viol)~0.5 keV G(E1-gamma) 20~200 keV G(M1-gamma)~1keV G(D(*)D(*)) ≥ 10 MeV g g g

I’ll emphasize recent results.

X(3872) ppX + p+p-J/y X(3872) B±K±p+p-J/y y’ y’ y’ X(3872) X(3872)

M(pp) looks like rpp Belle & CDF: JPC = 1++  most likely PRL 96 102002 c2/dof = 43/39 (CL=28%) kinematic limit≈mr Belle & CDF: JPC = 1++  most likely = 2-+  still possible

X(3872) properties (PDG2007) MeV MD0 + MD*0 = 3871.8 ± 0.4 MeV

What is it? c c cc1’ charmonium? L Maiani et al T-W Chiu & TH Hsieh PRD 71,014028 (2005) T-W Chiu & TH Hsieh PRD 73, 111503 (2006) D Ebert et al PLB 634, 214 (2006) … c c C Meng & KT Chao PRD 75,114002 (2007) cc1’ charmonium? NA Tornqvist PLB 590, 209 (2004) ES Swanson PLB 598,197 (2004) E Braaten & T Kusunoki PRD 69 074005 (2004) CY Wong PRC 69, 055202 (2004) MB Voloshin PLB 579, 316 (2004) F Close & P Page PLB 578,119 (2004) … too light?? P Lacock et al (UKQCD) PLB 401, 308 (1997)

Is X(3872) a Charmonium state? ?? ?? 3872MeV

Could the X(3872) be the cc1’ (23P1)? ?? 3872MeV Mass is too low cc1’ppJ/y violates Ispin G(gJ/y) should be >>G{rJ/y) expt: G(gJ/y) <<G(rJ/y)

Could the X(3872) be the hc2 (11D2)? ?? 3872MeV hc2’ppJ/y violates Ispin G(gJ/y) should be very small expt: G(gJ/y) 0.1 G(rJ/y) BKhc2 should be very small

Is X(3872) a diquark-diantiquark? Where are the “partner states”? Xu(3872) Xd(3872) X+(3872) X-(3872) u d c c u d c c c c d u c c u d BaBar: B+K-Xu B0K0Xd Bf(B0K-X+)Bf(X+p+p0J/y) < 0.4 M(Xd)-M(Xu)= 2(md-mu)/cosq Bf(B-K-X0)Bf(X+p+p-J/y)  8 ± 3 MeV (expected value is  2) L Maiani et al PRD 71,014028 (20050 PRD 71,031501 (2005)

BKSX & BK±X comparison BaBar 0803.2838 K± mode K± mode KS mode KS mode DM = 0.22 ± 0.90 ± 0.27 MeV Compared to 8±3 MeV (Maiani et al PRD 71 014028) DM = 2.7 ± 1.6 ± 0.4 MeV

X(3872)D0D*0? BaBar & Belle see a DD* threshold enhancement in BKDD* G. Gokhroo et al. (Belle) D0D0p0 B. Aubert et al. (BaBar) Phys. Rev. D77, 011102 (2008) Both groups see a high mass value & a Bf(DD*)  10x Bf(p+p-J/y) “DD* molecular” models Predicted Bf(DDp)  0.1Bf(p+p-J/y) (c.f. E.S. Swanson PLB 588, 189 (2004))

arXiv: 0801.3540 ” ”…

Still (5 yrs after discovery) no universally accepted explanation for the X(3872). (Although some kind of DD* molecular state --either real or virtual-- seems most popular.)

The 1-- states seen in ISR

e+e-  gisr Y(4260) at BaBar BaBar PRL95, 142001 (2005) fitted values: 233 fb-1 M=4259  8 +2 MeV G = 88  23 +6 MeV -6 -9 Y(4260)

Not seen in e+e-  hadrons J.Z.Bai et al (BES), PRL 88, 101802 (2006) s(e+e- hadrons) s(e+e-  m+m-) huge by charmonium standards BES data 4260 G(Y4260p+p- J/y) > 1.6MeV @ 90% CL X.H. Mo et al, PL B640, 182 (2006)

“Y(4260)” at Belle (New) BaBar values: M=4247  12 +17 MeV -32 G = 108  19 ±10 MeV -32 M=4259  8 +2 MeV G = 88  23 +6 MeV -6 -9 M=4008  40 +114 MeV G = 226  44 ±87 MeV -28 ??? Resonance? Thresh effect? …? C.Z Yuan et al (Belle) arXiv:0707.2541 PRL 99, 182004

No 1-- cc slot for the Y(4260) X.H. Mo et al, hep-ex/0603024 4260 4260

Is the Y(4260) a cc-gluon hybrid? qq-gluon excitations predicted 30 yrs ago lowest 1-- cc-gluon mass expected at ~4.3 GeV relevant open charm threshold is D**D (~4.28 GeV) G(ppJ/y) larger than that for normal charmonium G(e+e-) smaller than that for ordinary charmonium Horn & Mandula PRD 17, 898 (1977) Y(4260) seems to match all of these!!! Banner et al, PRD 56, 7039 (1997); Mei & Luo, IJMPA 18, 15713 (2003) Isgur, Koloski & Paton PRL 54, 869 (1985) McNeile, Michael & Pennanen PRD 65, 094505 (2002) Close & Page NP B443, 233 (1995)

DD** thresholds in & “Y(4260)” D** spectrum D1D No obvious distortions 4.28-mD M(p+p-J/y) GeV

BaBar’s p+p-y’ peak at 4325MeV D2D 298 fb-1 (BaBar) hep-ex/0610057 D1D e+e-gISR p+p- y’ Nevt = 68 (<5.7 GeV/c2) Nbkg = 3.1 1.0 M=4324  24 MeV G = 172  33 MeV above all D**D thresholds Not Compatible with the Y(4260) 2-prob < 5.7 GeV/c2 Y(4260) 6.5 10-3 (4415) 1.2 10-13 Y(4320) 29% BaBar PRL 98 252001 (2007) S.W.Ye QWG-2006 June 2006

4325 MeV p+p-y’ peak in Belle (new) Two peaks! (both relatively narrow) (& both above D**D thresh) (& neither consistent with 4260) M=4361  9 ±9 MeV G = 74  15 ±10 MeV M=4664  11 ±5 MeV G = 48  15 ±3 MeV BaBar values 4260 X.L. Wang et al (Belle) arXiv:0707.3699 PRL 99, 142002 (2007) M=4324  24 MeV G = 172  33 MeV 548 fb-1

Y(4360) & Y(4660) are above all D**D thresholds D** spectrum 4.66-mD 4.36-mD

No sign of Y(4360) or Y(4660) in e+e-  D(*)D(*) or DDp DD+DD*+D*D*+DDp Pakhlova (Belle) PRL 98, 092001 (2007)

The Y(4260) looks like a hybrid But the Y(4360) and Y(4660) -which look like the Y(4260)- do not look like hybrids.

Recent News electrically charged!!

M(p±y’) from BK p± y’ M2(py’) GeV2 M(py’) GeV M2(Kp) GeV2 M = 4433 ±4 ±1 MeV Gtot = 45 +17 +30 MeV Nsig =124 ± 31evts K*Kp Veto Veto K2*Kp? -13 -11 M2(py’) GeV2 6.5  M(py’) GeV M2(Kp) GeV2 S.-K. Choi et al (Belle) arXiv:0708.1790 PRL 100 2 weeks ago

Comments on the Z+(4430) Not a reflection from the Kp system (see backup slides) ~ No significant signal in B KpJ/y It has non-zero charge  not cc or hybrid c c charmonium Mass, width & decay pattern similar to Y(4360) & Y(4660)

comments There seems to be a new hadron spectroscopy in the M=3.5~5 GeV region Maybe more than one Bodes well for BESIII, Super-B factories & PANDA Some states are narrow even though they are far above decay thresholds e.g. Y(4660)ppy’ & Z+(4430)p+ y’ have large Q but G≈50 MeV characterized by large partial widths (Bfs) to hadrons+J/y (or y’) Br(X(3872)rJ/y) > 4.3% (Isospin=1) G(Y(4260)p+p-J/y) > 1.6 MeV G(Z(4430)py’) > 1 MeV States that decay to y’ not seen decaying to J/y (and vice-versa) Bf(Y(4660)ppy’) >> Bf(y(4660)ppJ/y)  same for Y(4360) Z(4430)py’ seen but pJ/y not reported Y(4260) not seen in Y(4260)ppy’ The new 1-- states are not apparent in e+e-D(*)D(*) cross sections There are no evident changes at the D**D mass threshold

New 1-- states p+p- J/y p+p- y’ K+K- J/y C.-Z. Yuan et al (Belle) PRD 77, 011105® (2008)

some of the states are near thresholds, DD thresholds DSDS thresholds some of the states are near thresholds, but this is not a universal feature

Are there XYZ counterparts in the ss- & bb- systems?

Belle: G((5S)pp(nS)) is Huge!!! (4S)pp(1S) 477 fb-1 from Belle (1/20 times the data & ~1/10th the crosssection) 8 times as many events! 2S 3S 4S (4S)  (1S) p+p- “(5S)”pp(1S) 23.6 fb-1 from Belle 325±20 evts! 44±8 evts Belle 0710.2577 K.F. Chen et al (Belle) PRL 100, 112001 (2008) (4 weeks ago)

PDG value taken for (nS) properties Partial Widths Assume “(5S)” = (5S) PDG value taken for (nS) properties N.B. Resonance cross section 0.302 ± 0.015 nb at 10.87 GeV PRD 98, 052001 (2007) [Belle] >100 times bigger!! Cf (2S)  (1S) p+p- ~ 6 keV (3S) 0.9 keV (4S) 1.8 keV

If there are bb versions of the XYZ’s, why not ss versions as well? It looks like there is a bb version of the Y(4260) lurking around the (5S) W.-S. Hou PRD 74, 017504 (2007) If there are bb versions of the XYZ’s, why not ss versions as well?

1-- Ys states around 2 GeV? Y(2175)f0(980)f from BaBar confirmed by BESII in J/y  h f f0(980) Y(2175)f0(980)f from BaBar e+e-  g f0(980)h @ Ecm ~10.6 GeV M(f0(980)f GeV M.Ablikim et al (BES) PRL 100, 102003 (2008) 6 weeks ago

Maybe the X(1835) is one too? J/ygX(1835) | p+p-h’ mostly ss X(1835) M. Ablikim et al (BESII), Phys.Rev.Lett.95:262001,2005

Luciano Maiani @ had-2007

Now it looks like there may also be XYZ-like spectroscopies for the s- & b-quark sectors Implications for BES-III: J/y (y’) running: systematic study of states decaying to f & h’ Higher energies: look for states decaying to lower charmonia (hc, J/y, cc1 etc.) …

Lots of pieces Are they all from the same puzzle? Y(3940) Z(4430) X(3940) Are they all from the same puzzle? X(4160) Y(4660) Y(4050) Y(4260) Y(4360) X(3872)

謝謝

Backup Slides

B-factories produce lots of cc pairs 0-+, 0++, 2++ 1- - only C =+ states

Could Z(4430) be a reflection from the Kp channel?

Cos qp vs M2(py’) p qp +1.0 M2(py’) cosqp -1.0 K +1.0 22 GeV2 (4.43)2GeV2 0.25 M2(py’) cosqp 16 GeV2 -1.0 M (py’) & cosqp are tightly correlated; a peak in cosqp  peak in M(py’)

Can interference between Kp partial waves produce a peak? Only S-, P- and D-waves seen in data interfere Add incoherently

Can we make a peak at cosqp≈0.25 with only S-, P- & D-waves? Not without introducing other, even more dramatic features at other cosqp (&,, other Mpy’) values.

Talk outline Y(3940) X(3940) Y(4260) X(4160) Z(4430) X(3872) Y(4660)