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Recent Results on Charm Hadrons from BaBar and Belle

Recent Results on Charm Hadrons from BaBar and Belle. Сессия Отделения Ядерной Физики РАН , Физика Фундаментальных Взаимодействий, ИТЭФ 27/11/07. Ruslan Chistov (ITEP). ▪ Introduction ▪ Evidence for D 0 -D 0 mixing ▪ Measurement of D s    and f Ds

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Recent Results on Charm Hadrons from BaBar and Belle

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  1. Recent Results on Charm Hadrons from BaBar and Belle СессияОтделения Ядерной Физики РАН , Физика Фундаментальных Взаимодействий, ИТЭФ 27/11/07 Ruslan Chistov (ITEP) ▪ Introduction ▪ Evidence for D0-D0 mixing ▪ Measurement of Ds and fDs ▪ Observation of new excited charm baryons c(3055/3123)+ ▪ Summary Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  2. Recent Results on Charm Mesons : Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  3. D0-D0 mixing in the SM Unlike mixing in K0, B0 and B0s systems, D0 system provides test for neutral meson mixing with down type quarks in the box. Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  4. D0-D0 mixing: experimental methods • Wrong sign (WS) hadronic decays e.g. K+ - ( K+ - 0, K+ - - + )t-dependent analysis required to disentangle • mixing and DCS contributions Strong phase difference between CF and DCS • Lifetime differencee.g. D0 K+K- (+) vs D0 K- + (0) • 0/ + = 1 + yCP yCP= y if no CP violation • Wrong sign (WS) semileptonic decays D0 K+l- RM = 1/2(x2 + y2) • Dalitz plot analysis D0 KS  - +t-dependent analysis: • interference of DCS and mixing • e.g. D0 K*+-CP final states e.g. D0 KS 0 (+) Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  5. D0 K+- Phys.Rev.Lett.96:151801,2006. Phys.Rev.Lett.97: 221803,2006. D0 K+- 0 RM<0.040 % 400fb-1 230.4fb-1 Many hints of D0 D0 mixing: ~2.1 Belle D0K ~2.3 BaBar D0K2/K3 ~2.2 Average yCP (PDG’06) D0 K+- +- D0-D0 mixing: Status 2006 Wrong sign (WS) hadronic decays: K+ -, K+ - 0, K+ - - +t-dependent analysis to disentangle mixing and DCS Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  6. hep-ex/0703020v1 403090 candidates WS 384fb-1 D0-D0 mixingfrom BaBar points: data – no-mixing fit curve : ”mixing fit” – “no mixing fit” Fit with mixing is better match to data! Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  7. 3.9 no-mixing point mixing CL contours No CPV D0-D0 mixing from BaBar: Results • x’2 and y’2 CL contours • calculated from the change in log likelihood • include systematic errors x’2 = - (0.220.300.21)x10-3 y’= (9.74.43.1)x10-3 Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  8. D0-D0 mixing at Belle: ycp • Measure relative lifetime difference: D0 K-+ and D0 K+K- (+ -) • mixing parameter: • yCP= y· cos- 1/2AMx· sin • CP conservation: AM = sin = 0 ; yCP= y = /  • Search for CPV by measuring • A= 1/2AMy· cos - x· sin Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  9. D0-D0 mixing at Belle: ycp results Visual demonstration of non-zero y: Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  10. Decay amplitude assuming M = M (no CPV): for D0 m2= m2(KS) , for D0 m2= m2(KS) t - dependence is contained in D0-D0 mixing at Belle:Dalitz analysis D0 K0S-+ Study self-conjugate decay D0 K0S -+ t-dependence of Dalitz plot distribution provide direct access to x and y!!! Strong phase difference between CF and DCS amplitudes fixed by Dalitz fit! Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  11. Belle results on Dalitz analysis D0 K0S-+ disfavor no-mixing x=y=0 point with significance 2.2  Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  12. D0-D0 mixing measurements average Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  13. Measurement of Ds++ and fDsat Belle Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  14. Reconstruction ofDs++ Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  15. Measurement of Ds++ and fDsat Belle (results) ! Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  16. Recent Results on Charm Baryons : Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  17. Observation of new excited charm strange baryons at Belle Λc+K-π+ Ξc(3080)+ NEW hep-ex/0607042 Λc+K-π+ Ξc(2980)+ NEW Ξc(3080)+ BaBar confirmed Ξc(2980)+ PRL97,162001 Λc+Ksπ- Ξc(3080)0 NEW New decay mechanism: s-quark → meson Measurements of M and Γ are consistent Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  18. Observation of Ξc(3055)+and Evidence for Ξc(3123)+ at BaBar Ξc(3055)+ NEW Ξc(3080)+ Ξc(2980)+ Σc(2455)++K-→Λc+K-π+ Ξc(3080)+ Σc(2520)++K- For all new c  Ξc(3123)+ evidence Mass  D-wave excitations ? Ξc(2980) 1/2+, 3/2+,.. Ξc(3080) 5/2+,.. hep-ex/... (preliminary) More experimental studies to assign JP. Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  19. Discussion of New cx States Observed Properties: •Charm and strange quarks in the final state (Λc+ and K-); •These new charm baryons have *large masses (largest in grand family of charm baryons), *finite widths; •Neutral partners also observed not double charm baryons Most natural interpretation: excited charm strange baryons which could be D-wave excitations. Possible JP are 1/2+(or 3/2+) and 5/2+ (H.-Y.Cheng, C.-K.Chua, hep-ph/0610283; J.L.Rosner, hep-ph/0612332) Note:  Not seen in M(Λc+K-) and M(Λc+K-+-) spectra! Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  20. Observation of cx(2980)+/0 c*0/++/- at Belle Search for another, “natural” channel for the new states cx M(Ξc(2645)0π+) M(Ξc(2645)+π-) Ξc(2815)0 Ξc(2815)+ Ξcx(2970)0 Preliminary Ξcx(2970)+ No Ξcx(3080)0 ?? No Ξcx(3080)+ ?? Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  21. Observation of Λc(2940)+and Λc(2880)+D0p BaBar Belle c(2880)+ c(2880)+ c(2940)+ c(2940)+ M(Σc(2455)0,++π±) New decay mechanism of excited Λc ! Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  22. Study of B+→Λc+Λc-K+ by BaBar(preliminary) Originally, B+→Λc+Λc-K+ decay has been observed by Belle PRL97,202003 (2006) BaBar: confirmation, resonant structure. Λc+K- Λc+ Λc- K- NEW B meson signal phase-space sidebands mbc (GeV/c2) Excited Ξc? not seen in continuum BaBar  “More data are needed before firm conclusions can be drawn.” Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  23. Summaryon New Charm Baryons New charm baryons with new decay mechanism were discovered by BaBar and Belle: cK threshold D0p threshold c(2880)+ c and D0p (!), c(2940)+ mostly to D0p, (csuppressed) cx(2980)  c* and cK (cK), cx(3080)  only to cK (c(*)K), (no signal for c*) Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  24. Summary • This year D0-D0 mixing results : • New D0K+- study at BaBar: 3.9 of (x’,y’) (0,0) (past year at Belle: 2.1 of (x’,y’) (0,0) • New Dalitz analysis D0 K0S -+ at Belle: 2.7 of (x,y) (0,0) • New yCP measurement at Belle: 3.2 of y 0 (past year at BaBar: 1.9 of y 0) ● Combination of existing D0-D0 mixing results established at ~5σ ● New measurement of fDs fromBelle in good agreement with previous results and LQCD ● A lot of new charm baryons observed : waiting interpretation from theory Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  25. Back up slides Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  26. Integrated luminosity May ‘99 KEKB asymmetric-energy e+e- collider and Belle detector e+e- Y(4S) {ll, cc, qq} Not only EWP and CP! > 1 fb-1/day > 730 fb-1 Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  27. Angular analysis of Ds1(2536)+D*+K0s at Belle Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  28. Angular analysis of Ds1(2536)+D*+K0s at Belle (cont’d) RESULT: Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

  29. Observation of new excited charm strange baryon at Belle and BaBar PRL97,162001 Λc+K-π+ Ξc(3080)+ NEW Ξc(2980)+ NEW New decay mechanism:s-quark → meson. Λc+K-π+ hep-ex/0607042 Ξc(3080)+ BaBar confirmed Λc+Ksπ- Ξc(2980)+ Ξc(3080)0 NEW BaBar confirmed also Ξc(3080)0 Measurements of M and Γ are consistent Mass D-wave excitations ? Ξc(2980)1/2+, 3/2+,.. Ξc(3080)5/2+,.. Rosner Chen, Chua, PRD75, 094017 Garcilazo, Vijande, Valcarce, JPG34, 961 Chen, Chen, Liu, Deng, Zhu, PRD75, 094017 Ebert Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP) More experimental studies to assign JP.

  30. Observation of Ξc(2980) and Ξc(3080) by Belle PRL97,162001 hep-ex/0607042 Λc+K-π+ Λc+K-π+ Ξc(3080)+ NEW Ξc(3080)+ BaBar confirmed Ξc(2980)+ NEW Ξc(2980)+ New decay mechanism:s-quark → meson. resonant structure Λc+Ksπ- Ξc(3080)0 NEW BaBar confirmed also Ξc(3080)0 Measurements of M and Γ are consistent Mass D-wave excitations ? Ξc(2980)1/2+, 3/2+,.. Ξc(3080)5/2+,.. Rosner Chen, Chua, PRD75, 094017 Garcilazo, Vijande, Valcarce, JPG34, 961 Chen, Chen, Liu, Deng, Zhu, PRD75, 094017 Ebert Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP) More experimental studies to assign JP.

  31. : Ruslan Chistov ▪ Recent Results on Charm hadrons from BaBar and Belle (27/11/07, ITEP)

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