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B  D (*) D (*) K Jolanta Brodzicka, Henryk Palka INP Krakow B G M December 08 , 2004

B  D (*) D (*) K Jolanta Brodzicka, Henryk Palka INP Krakow B G M December 08 , 2004. Outline : On B  D (*) D (*) K for  250fb -1 On D sJ (2700). B +  D - D + K + B 0  D - D + K 0 S. 1 st observation. 1 st observation. B +  D * - D + K + B 0  D * - D + K 0 S.

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B  D (*) D (*) K Jolanta Brodzicka, Henryk Palka INP Krakow B G M December 08 , 2004

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  1. B  D(*)D(*)K Jolanta Brodzicka, Henryk Palka INP Krakow BGM December08, 2004 • Outline : • OnB  D(*)D(*)K for 250fb-1 • On DsJ(2700)

  2. B+ D-D+K+B0 D-D+K0S 1st observation 1st observation B+ D*-D+K+B0 D*-D+K0S B+ D*-D*+K+ B0 D*-D*+K0S(shown last year) 1st observation Changes since last BAM • Full data sample re-skimmed because: • low efficiency in DK0modes has been noticed • inconsistent IP cuts for svd1 and svd2 data • Improvements obtained: • new B  D(*)D(*)Kchannelsobserved colour suppressed and usefull for CPV • S/B increase • DsJ(2700) D0K+ : conclusions remain valid J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  3. colour suppressed decays 2-dimMbc vs.E unbinned likelihoodfit used • B+ D-D+K+ for Mbc>5.273 GeV for E<15MeV N/7MeV N/2.5MeV S = 45.6±8.5 stat signif = 8.0 1st observation • B+ D*-D+K+ for Mbc>5.273 GeV for E<30MeV N/7MeV N/2.5MeV S = 73.5±9.9 stat signif = 12.5 • B+ D*-D*+K+ for E<25MeV for Mbc>5.27 GeV N/7MeV S = 11.9±3.6 stat signif = 6.8 N/2.5MeV 1st observation Mbc E J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  4. modes interesting for CPV • B0 D-D+K0S for Mbc >5.273 GeV for E<15MeV N/7MeV S = 38.0±8.1 stat signif = 7.4 N/2.5MeV 1st observation • B0 D*-D+K0S for Mbc >5.273 GeV for E<30MeV N/7MeV N/2.5MeV S = 60.4±9.5 stat signif = 14.7 • B0 D*-D*+K0S for Mbc >5.27 GeV for E<25MeV N/7MeV S = 14.7±3.9 stat signif = 9.1 N/2.5MeV E Mbc J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  5. Preliminary J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  6. for Mbc >5.273 GeV for E<15MeV N/7MeV N/2.5MeV • B+ D0D0K+ E Mbc for Mbc >5.273 GeV for E<15MeV N/7MeV E S = 151.5±18.0 S/B=0.7 • B0 D-D0K+ N/2.5MeV S = 208.5±19.0 S/B=0.54 N/2.5MeV Mbc Fitting method: 2-dimMbc vs.E unbinned likelihood fit L_Sig(Mbc, E) = S•(G (Mbc)•G(E)) + S•(G(Mbc)•G(E)) + S2•(G(Mbc)•G(E))2 L_Bckg (Mbc, E) = B•ARG (Mbc) • POL_2 (E) L= L_Sig + L_Bckg S, S2: regions with missing ,2 J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  7. Dalitz plot and projections for LR > 0.04 B+ D0D0K+ Background:elliptical strip 6 to 10 in Mbc, E, surrounding the signal region Mbc > 5.273 GeV E<15 MeV (~3 ) M2( D0K+) DsJ(2700) DsJ(2573) N / 20MeV (4160) M2( D0D0) (3770) M( D0K+) M( D0D0 ) N / 20MeV N / 20MeV M( D0 K+) for signal-box events : (4160) (3770) DsJ(2700) reflection (4040) DsJ(2700) (4160) reflection (3770)reflection (3770)reflection DsJ(2700) reflection DsJ(2573) (4160) reflection J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  8. Background subtracted mass distributions 2dim Mbc vs.E fits ininv. mass bins B signal in mass bins (4160) DsJ(2700) B+ D0D0K+ M( D0K+) M( D0D0 ) Signal / 50MeV M( D0K+) wrong flavour comb. (3770) Signal / 50MeV Signal / 50MeV J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  9. Signal / 50MeV M( D0D0 ) M( D0K+) (4160)reflection Can we explainM( D0K+) distributions by reflections from known states? Assumption: only (4160) in M( D0D0 ) distr. @ 4GeV region N = 54.4 ± 10.8 M = 4160 MeVfixed  = 80 MeV fixed Signal / 50MeV N = 69.8 ± 11.5 M = 4100 MeVfixed  = 100 MeV fixed Signal / 50MeV Signal / 50MeV does not explain M( D0K+) bump at 2.7GeV J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  10. total (4160) yield: 27 ±11 events (for 2nd half helicity distr: 20% smaller eff ) M( D0D0 ) M( D0D0 ) M = 4160 MeVfixed  = 80 MeV fixed N = 34.9 ± 7.2 M = 3778 MeVfixed  = 25.3 MeV fixed Charmonia • (4160) To estimate of the (4160)contribution to the 2.7GeV peak: Signal / 50MeV M(D0D0) for M(D0K+) > 2.97GeV (4160) in½ helicity distr. 14.8 ±6.4events (other fit variants checked) contribution to theDsJ(2700): 12 events • (3770) Signal / 25MeV • resonance described by non-relativistic Breit-Wigner • nonresonant component – threshold function J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  11. B+ D0D0K+ N = 70.0 ± 12.2 M = 2716± 13 MeV  = 130 ± 31 MeV fitted B Signal DsJ(2700) M(D0D0)>3845 MeV (3770) region removed: Fit to background-free D0K+ mass spectrum • resonance described by non-relativistic Breit-Wigner • Phase Space (nonresonant component) is described by 3body MC PS • Reflection shape: (according to cos2 angular distribution of (4160) )from MC : B+ (4160) K+ Signal / 50MeV systematic error from (4160) param.: N: ± 4 M:± 2 MeV : +3 -10 MeV M( D0K+) reflection from (4160) (normalized to 27) (+ non-resonant component ) (interference effects – neglected) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  12. Explanation ofmass spectra B+ D0D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D0K+) M( D0D0 ) (4160) 27 ± 12 M=4160 =80MeV (3770) 35 ± 7 M=3770 =25MeV Signal / 50MeV DsJ(2700) 70± 12 M=2700 =140MeV spin J=1 assumed for DsJ(2700) wrong flavour comb. Contributions from considered states: (normalized to yields) (shapes from MC studies) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  13. K+ D0K+  B D D0 fitted B Signal (corrected for acceptance) (4160) reflection Angular distribution Helicity angle  : angle between K+momentum in D0K+rest frame and D0K+momentum (the boost direction) in B rest frame DsJ(2700) region: B+ D0D0K+ signal-box 2.58 < M(D0K+) < 2.84 GeV (130MeV window ) cosdistribution obtained using 2-dim Mbc vs.E fit ineach cosbin(to subtract background) Acceptance for signal MC B+  D0 DsJ(2720)(K)(K) For DsJ(2720)J=1 assumed Ang.distribution: cos2 Eff. corrected signal J=1 hypothesis /n.d.f = 0.1/4 J=2hypothesis /n.d.f = 8.1/4 J=0hypothesis /n.d.f = 16/4 Acceptance cos cos J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  14. D0 Helicity angle  : angle between D0momentum in D0D0rest frame and D0D0momentum in B rest frame D0D0  B K+ D0 DsJ(2700) reflection Angular distribution of  cosdistribution obtained using 2-dim Mbc vs.E fit ineach cos bin (to subtract background) (4160) region: B+ D0D0K+ signal-box 4.0 < M(D0 D0) < 4.2 GeV (100MeV window ) (3770) region: B+ D0D0K+ signal-box 3.7 < M(D0 D0) < 3.845 GeV (3 ) Eff. corrected signal Eff. corrected signal cos cos J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  15. for signal-box events : Mbc > 5.273 GeV E<18 MeV (~3 ) Dalitz plot and projections B0 D-D0K+ LR > 0.01 Backgroundnormalized to number of bckgd. events in signal box DsJ(2573) DsJ(2700) DsJ(2700) reflection N / 20MeV M2( D0D- ) M2( D0K+) M( D-D0 ) DsJ(2700) DsJ(2700) reflection DsJ(2573) N / 20MeV N / 20MeV M( D0K+) M( D-K+) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  16. Background subtracted mass distributions 2dim Mbc vs.E fits ininv. mass bins B signal in mass bins B0 D-D0K+ • DsJ(2700) observed and a shoulder (DsJ(2573) ?) Signal / 50MeV M( D0K+) Signal / 50MeV Signal / 50MeV M( D-D0 ) M( D-K+) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  17. N = 122.4 ± 17.9 M = 2710 ± 9 MeV  = 127 ± 27 MeV N = 12.6 ± 4.0 M = 2573MeV fixed  = 15 MeV fixed fitted B Signal DsJ(2573) DsJ(2700) Fit to background-free D0K+ mass spectrum • resonances described by non-relativistic Breit-Wigners • DsJ(2573)the convolution BW  G(=50MeV) • Phase Space (nonresonant component) is described by 3body MC PS B0  D-D0K+ Signal / 50MeV M( D0K+) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  18. DsJ(2573) 13± 4 M=2573 =15MeV DsJ(2700) 122± 18 M=2700 =140MeV Explanation ofmass spectra spin J=1 assumed for DsJ(2700) B0 D-D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D-D0 ) wrong flavour comb. Signal / 50MeV Contributions from considered states: (normalized to yields) (shapes from MC studies) M( D-K+) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  19. fitted B Signal (corrected for acceptance) Angular distribution DsJ(2700) region: B0 D-D0K+ signal-box 2.58 < M(D0K+) < 2.84 GeV (130MeV window ) B0  D-D0K+ Eff. corrected signal Acceptance for signal MC B0  D-DsJ(2700)(K)(K) For DsJ(2700)J=1 assumed cos Acceptance cos J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  20. Summary • results shown at last BAM confirmed with reanalised data • new channels observed ( 3 of them for the first time) • publish result on DsJ(2700) in B+ D0D0K+ • publish BF’s • write PhD thesis Plan J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  21. Backup slides J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  22. J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  23. B0 D*-D0K+ S = 218.1±17.8 S/B=1.3 • B- D0D*-K0S S = 52.6±9.1 S/B=1.0 E Mbc J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  24. Analysis method • selection cuts accepted events :R2< 0.3 tracks :IP_dz< 5cmIP_dr< 0.4cm K± :P(K/) > 0.4± :P(/K) > 0.1electron veto: el_id < 0.95 K0S:M(+ -) - MKs <15MeVonly goodK0saccepted 0:E >50 MeVM( ) -M0 <15MeV • D(*) reconstruction D0K, K3, K0, Ks, KKBF ~ 28%of total D± K, Ks, KK, KsKBF ~ 12%of total M(D)-M(DPDG)  < 20MeV ( D0 K0: -50MeV ) vertex fit (cl > 0.) and mass constraint fit applied p(D) < 2 GeVin (4S) system D(*) ± D0± M(D*)-M(D)-mPDG)  < 2.5MeV vertex fit (cl > 0.) • B D(*)D(*)Kreconstruction B vertex fit:with IP and B constraints Mbc> 5.2 GeV -0.40 < E < 0.35 GeV J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  25. Dplots for ~11fb-1after preselection p(D) < 2GeVin (4S) system D0K D0K3 D probabilities (LR_D ): LR_D LR_D S(MD) LR_D ( MD )= MD MD S(MD) B(MD) + D0K0 LR_D D±  K D± Ks MD LR_D LR_D MD MD Likelihood ratios: S(MD), B(MD)parameterization from fitstodata (inclusively reconstructed D0, D± in each decaymode separately ) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  26. B probability ( LR_B ): LR_B = LR_D1× LR_D2 B+ D0D0K+ B0 D-D0K+ LR_B LR_B M_D0 * M_D0 M_D0 * M_D- LR_B vs. M(D1)*M(D2) for signal box-events : • LR_B used for: • choice of best B candidate(withmax LR_B) • background discrimination J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  27. LR_B cut (good for background reduction and S/B improvement) B+ D0D0K+ Data for 250fb-1 for Mbc>5.27GeV Signal MC B+ D0D0K+ no LR_B cut S / sqrt (S + B ) LR_B > 0.04 LR_B > 0.1 LR_D0 * LR_D0cut Signal MC BF = 1.5 * 10-3 B+ D0D0K+ B+ D0D0K+ Background:Mbcsideband E J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  28. M( D0D0 ) M( D0D0 ) • (4160) fit variants M(D0D0) for M(D0K+) > 2.97GeV ( ≡ ½ of the (4160)helicity distr.) N = 17.3 ± 7.0 M = 4160 MeVfixed  = 100 MeV fixed total (4160) yield Signal / 50MeV 31 ± 13 N = 66.3 ± 12.1 M = 2717 ± 14 MeV  = 133± 33 MeV N = 23.4 ± 7.1 M = 4100 MeVfixed  = 100 MeV fixed total (4160) yield Signal / 50MeV Signal / 50MeV 42 ± 13 M( D0K+) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  29. N = 72.9 ± 11.7 M = 2714 ± 10 MeV  = 120 ± 26 MeV • no (4160) contribution to the 2.7GeV peak: DsJ(2700) Signal / 50MeV M( D0K+) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  30. Explanation ofmass spectra B+ D0D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D0K+) M( D0D0 ) (4160) 42 ± 13 M=4100 =100MeV (3770) 35 ± 7 M=3770 =25MeV Signal / 50MeV DsJ(2700) 66± 12 M=2700 =140MeV spin J=1 assumed for DsJ(2700) (4160)gen. with:M=4100MeV =100MeV wrong flavour comb. Contributions from considered states: (normalized to yields) (shapes from MC studies) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  31. Explanation ofmass spectraspin J=0 assumed for DsJ(2700) B+ D0D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D0K+) M( D0D0 ) (4160) 27 ± 12 M=4160 =80MeV (3770) 35 ± 7 M=3770 =25MeV Signal / 50MeV DsJ(2700) 70± 12 M=2700 =140MeV Contributions from considered states: (normalized to yields) (shapes from MC studies) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  32. Explanation ofmass spectraspin J=2 assumed for DsJ(2700) B+ D0D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D0K+) M( D0D0 ) (4160) 27 ± 12 M=4160 =80MeV (3770) 35 ± 7 M=3770 =25MeV Signal / 50MeV DsJ(2700) 70± 12 M=2700 =140MeV Contributions from considered states: (normalized to yields) (shapes from MC studies) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  33. DsJ(2573) 13± 4 M=2573 =15MeV DsJ(2700) 122± 18 M=2700 =140MeV Explanation ofmass spectra spin J=0 assumed for DsJ(2700) B0 D-D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D-D0 ) wrong flavour comb. Signal / 50MeV Contributions from considered states: (normalized to yields) (shapes from MC studies) M( D-K+) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  34. DsJ(2573) 13± 4 M=2573 =15MeV DsJ(2700) 122± 18 M=2700 =140MeV Explanation ofmass spectra spin J=2 assumed for DsJ(2700) B0 D-D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D-D0 ) wrong flavour comb. Signal / 50MeV Contributions from considered states: (normalized to yields) (shapes from MC studies) M( D-K+) (plotted by adding) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  35. fitted B Signal Angular distributions uncorrected for acceptance DsJ(2700) region: B DD0K+ signal-box 2.58 < M(D0K+) < 2.84 GeV B+ D0D0K+ B0  D-D0K+ cos cos J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  36. B+ D0D0K+ M2( D0D0) Efficiency map Efficiency [‰] M2( D0K+) J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

  37. B+ D0D0K+ b  cW - c c s + dd (uu) • External + Internal diagrams • Both DK and DD states expected • D0K+ is exotic _ Physics motivations B  D(*)D(*)K : good place to explore spectroscopy: D(*)K from W vertex Leading quark diagrams: B0  D-D0K+ B0  D*-D0K+ • only External diagram • D0K+is the only non-exotic comb., D*-D0 have > 2q content J.Brodzicka, H.PalkaINP Krakow BGM December 08, 2004

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