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A. Drutskoy University of Cincinnati

1. A. Drutskoy University of Cincinnati. Charm spectroscopy. American Physical Society Meeting. April 14-17, 2007, Jacksonville, Florida. Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy. 2. Outline.

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A. Drutskoy University of Cincinnati

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  1. 1 A. Drutskoy University of Cincinnati Charm spectroscopy American Physical Society Meeting April 14-17, 2007, Jacksonville, Florida . Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  2. 2 Outline Meson classification, potential models. Recent experimental results on excited D** production. Experimental results and classification of DsJmesons. Charmonium state X(3872). Charmonium states X(3940), Y(3940) and Z(3930). New charmonium states Y(4260) and Y(4320). New charm baryons. Conclusions. CLEO Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  3. 3 Conventional and unconventional mesons 1. Conventional quark- antiquark mesons (qq). 2. Glueballs (gg, ggg). Lightest glueballs JPC = 0++ and 2++. 3. Hybrid mesons (qqg). Ground states JPC = 0- +, 1- +, 1- -, 2- +. 4. Tetraquarks (qqqq). Large binding energy. Non-qq flavor? 5. Molecular states (qq qq). Small binding energy. Deuteron-like. 6. Mixture of these states. These states can be separated using information on masses, widths, quantum numbers, production and decay modes (rates). Theoretical calculations, potential models, lattice calculations. Coupled-channel effects. IfMresclose to M1+M2 mass shift? Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  4. 4 Potential models, energy splitting s1 s2 L s1 s2 Jq S12 L (LS2)S1 L (S1 S2) Jqis a good quantum number => separated D(s) meson spin-doublets: (0-,1-), (0+,1+), (1+,2+). Energy splitting: singlet and triplet. 1- 1- cc cq Y’ 2S 2S 0- 0- h’c Jq=3/2 2+ Jq=1/2 Ds2 2+ cc2 Mass 1+ L=1 1P 1+ 1+ 1+ D’s1 1P L=1 cc1 Ds1 hc 0+ 0+ cc0 D’s0 1S 1S 1- 1- J/Y Ds* L=0 L=0 0- 0- hc Ds Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  5. 5 D**0 and D**+ meson searches D**mesons are studies using fully reconstru- cted B meson decays. It provides strong background suppression. hep-ex/0611054(2006) ~388M No restrictions on D** quantum numbers inBdecays. Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  6. 6 Orbitally excited D**0 and D**+ mesons 1.2 4.7 (2465.71.80.8 ) MeV/c2 (49.73.84.1 4.9) MeV Theory and experiment are in good agreement Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  7. 7 DsJmeson spectroscopy Measured masses of DsJ(2317) and DsJ(2460)are significantly lower than those predicted in potential models. DsJ(2573) DsJ(2536) * Ds DsJ(2460) Ds DsJ(2317) Their quantum numbers 0+and 1+ are well established now. Many theoretical papers have been published since 2003, trying to explain narrowDsJ(2317)andDsJ(2460)resonances:chiral partners, DK threshold effect, four-quark states? + + Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  8. fitted B signal 8 New DsJ(2700)meson in B+ >D0D0K+ decay hep-ex/0608031 449M BB ■ B+→D0DsJ(2700)■ B+→ψ(3770)K+ ■ B+→ψ(4160)K+■B+→D0D0K+NR■threshold contribution DsJ(2700) Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  9. 9 DsJ(2700)helicity angle distribution J=02/ndf= 185/5 J=12/ndf= 7/5 J=22/ndf= 250/5 JP=1- is favored. cs radial excitation 23S1 ? (predicted by potential models at M~2720MeV) ? or chiral symmetry doublet? eff. corrected DsJ(2700) helicity angle distribution Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  10. 10 New DsJ(2860)meson in e+e- >D0K+X, D+K0X hep-ex/0607082 240 fb-1 103 BG subtracted Strong peak at 2.573 GeV/c2 DsJ(2860) Hint of a broad state at 2.69 GeV/c2 M(DK) (GeV/c2) =>New resonance at 2.86 GeV/c2 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  11. 11 DsJmeson spectroscopy DsJ(2700) : Jp = 1- Is Ds(2700) state the radial excitation 23S1 (predicted by potential models at M~2720MeV) ? DsJ(2860) ?? Ds(2700) ? DsJ(2573) DsJ(2536) DsJ(2860) -> D0 K+ (0-0- ) DsJ(2460) * Ds DsJ(2317) Ds Is DsJ(2860) state the radial excitation of DsJ(2317) ? Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  12. 12 Charmonium spectroscopy cc hc’’ cc1’ hc2Y2 Y3 hc’ MD*+MD 2MD hc’ Y’ cc2 hc cc1 cc0 blue lines: predictions black lines: measurements J/Y hc Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  13. 13 hc(1P1) andhc(2S) charmonium states Belle first observedc(2S) atB->K(KsK+-) and then at e+e- -> J/ X c(2S)was then confirmed by CLEO and BaBar With Inclusive c decay CLEO 3.08M (2S) hc 15040 events stat. sig. 3.8 B→ K(KsK+p-) MPDG=3637.7±4.4MeV/c2 M(hc)=3524.90.70.4 MeV/c2 M(0 recoil) (GeV) CLEO PRL 95 (2005) 102003 CLEO PRD 72 (2005) 092004 Belle PRL 89 (2002) 102001 BaBar PRD 92 (2004) 142002 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  14. 14 X(3872) > J/yp+p- decay First observed by Belle in B± ->K±(J/+-).Then confirmed byCDF, D0andBaBar. Belle X(3872) 304M B’s ’ X(3872) ’ Events/10 MeV 220 pb-1 PRL 91 (2003) 262001 PRL 93 (2004) 072001 X(3872) 230 pb-1 X(3872) BaBar 234M B’s M(J/yp+p-) PRD 71 (2005) 071103 PRL 93 (2004) 162002 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  15. 15 Evidence for X(3872) > gJ/y PRD 74 (2006) 071101R hep-ex/0505037 287M BB X(3872) X(3872) 275M BB MJ/ (GeV/c2) MJ/ (GeV/c2) • 19.4 5.7 events • stat. sig.: 3.4  • 13.6 4.4 events • stat. sig.: 4.0  Belle/BaBar average: It suggests that C parity of X(3872) is +1 Low g J/y rate > bad candidate for c’c1 ??? (1++). Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  16. 16 Evidence for sub-threshold X(3872) > w J/y hep-ex/0505037 275M BB 10.63.6 events 4.3  B±->K±(J/+-p0) X(3872) : C=+1 M(+-0) (GeV/c2) • no signals for charged partners of X(3872) (BaBar) • no signal for X(3872) -> J/  (BaBar) • no evidence in fusion and radiative production (CLEO) Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  17. 2/d.o.f=11/9 |cosl| 2/d.o.f=5/9 |cos| 17 X(3872) quantum numbers • Angular distributions in B->X(3872)K decay X(3872) -> J/Yp+ p- : • gfavors 1++. hep- ex/0505038 1++ 1++ • Hint for B->X(3872)K withX(3872)->D0D0p0 favors 1++ (disfavors 2++) (next slide). PRL 96 (2006) 102002 • Preference for high p+p- mass region. Possible interpretation: X(3872)->J/yr • Possible X(3872) quantum numbers: • Jp=1++ (or 2-+) . Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  18. 18 X(3872) interpretation ? < 1 MeV/c2 DD* X(3872) DD Interpretation of X(3872) is unclear. Molecular interpretation ? Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  19. 19 Near threshold D0D0p0 enhancement in B >D0D0p0K If X(3872) is a loosely bound S wave D0D0* molecule, an enhancement in the near threshold D0D0*invariant mass spectrum is expected. PRL 97 (2006) 162002 • 23.4 5.6 events • 6.4  414 fb-1 M = 3875.2  0.7 +0.3 0.8 MeV/c2 -1.6 =8.8+3.1 -3.6 If it is X(3872), J=2 is suppressed, JPC=1++ is favored. X(3872) -> D0D0* production rate is large. This is difficult to explain within molecular interpretation. Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  20. 20 X(3872) in B0 and B+ decays PRD 73 (2006) 011101 R 6.1 2.5 232M BB S-wave D0D*0: E. Braaten et al., PRD 71, 074006 K+ D0 Data are not in favor of this model. X(3872) B+ D*0 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  21. X e- e+ J/y 21 Observation of X(3940) in e+e- > J/ X PRL 98 (2007) 082001 357 fb-1 M = (3943  6 6) MeV/c2  < 52 MeV/c2 (90% C. L.) Stat. sig. > 5.0  Mrecoil(J/) above DD and D*D thresholds not seen in DDand J/yw D*D is the dominant decay of X(3940) > JPC = 1++ is preferred, candidate c’c1 (or hc(3S) ? ). Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  22. 22 Y(3940) >wJ/ near threshold peak in B >K w J/y PRL 94 (2005) 182002 253 fb-1 2/d.o.f.=115/11 2/d.o.f.=15.6/8 stat. sig.=8.1 -> above D*D threshold -> not found in DD or D*D final states M(wJ/) If it is treated as a S-wave BW: M = 3943  11  13 MeV/c2  = 87  22  26 MeV/c2 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  23. , 23 Search for ccJ via gg >DD and Z(3930). 395 fb-1 PRL 96 (2006) 082003 • N sig. = 64  18 • stat. signif. 5.3  • M=3929 52 MeV/c2 • =29 102 MeV/c2 D0D0 + D+D- Z(3930) Angular analysisfavors J=2 Good candidate forc’c2 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  24. 24 Observation ofY(4260) in ISR events and B decays First observed by BaBar, then confirmed byCLEOandBelle. PRL 95 (2005) 142001 553 fb-1 Y(4260) 233 fb-1 Jp = 1-- hep- ex/0612006 CLEO 4.9 sig. 3.1 sig. B->Y(4260)K Y(4260)-> J/yp+p- PRD 73 (2006) 011101 13.3 fb-1 PRD 74 (2006) 091104 Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  25. 25 What is theY(4260) state ? -4.2 -3 -6 -16 -6 -4 -25 ~2.5s different 1-- state, but not seen in e+e--> hadrons (local minimum). Interpretations: • Hybrid charmonium:Zhu, PLB 625 (2005) 212; Close & Page, PLB 628 (2005) 215; Kou and Pene, PLB 631 (2005) 164; Luo and Liu, PRD 74 (2006) 034502, … • Tetraquark:Ebert et al., PLB 634 (2006) 214; PRD73(2006)094501, ... • Molecules:Liu et al., PRD 72 (2005) 054023 (R); Yuan et al., PLB 634 (2006) 399 Qiao, PLB 639 (2006) 263, … • Conventional: F. J. Llanes-Estrada, PRD 72 (2005) 031503(R), … Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  26. 26 Observation ofY(4320) >p+p-y(2S) in ISR events M(+-(2S) Y(4260) Y(4350) 3-body phase space hep- ex/0610057 If this peak is a single resonance: What is Y(4320)? Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  27. DD* DD X(3872) Y(4320) 27 What are X(3872), Y(4260) and Y(4320) ? Y(4260) Currently on market:X(3872)-molecular,Y(4260)& Y(4320)- hybrids Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  28. 28 Charmed baryons hep-ex/0603052 hep-ex/0606051 Lc(2880)+ cx(3077)+ Lc(2940)+ cx(2980)+ 287 fb-1 Mass(Λc+ K- +)(GeV/c2) c(2980)+ : M=2978.52.12.0 MeV/c2 =43.5 7.57.0 MeV/c2 Inclusive D0p mass spectrum D0 mass sidebands Belle<>BaBar confirmed Many new charm baryon resonances Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

  29. 29 Conclusions Many new open charm and charmonium (charmonium-like) states are observed (DsJ(2700), DsJ(2860), X(3872), X(3940), Y(3940), Z(3930), Y(4260), Y(4320), baryons… ). Interpretation of some of these states is not clear. New ideas on market: four-quark states, molecular states, hybrids. Maybe some mixture of two-quark and unconventional states? It is important to determine quantum numbers of all observed states. More decay channels should be studied. It is theoretically difficult to explain some measurements of production and decay rates for some (even conventional) states (no time to discuss it in this talk). Charm spectroscopy, APS meeting, Apr 14 -17, 2007, Jacksonville, Florida, A. Drutskoy

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