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JOLANTA BRODZICKA

Doubly charmed B decays. B  D(*)D(*)K. ( for ~140 fb -1 ). November 05, 2003. JOLANTA BRODZICKA. Institute of Nuclear Physics, Krakow. Plan. b  c c s transition “ wrong-sign” D production physics motivations analysis details

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JOLANTA BRODZICKA

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  1. Doubly charmed B decays B D(*)D(*)K ( for ~140 fb-1 ) November 05, 2003 JOLANTA BRODZICKA Institute of Nuclear Physics, Krakow

  2. Plan • b  c c stransition “wrong-sign” D production • physics motivations • analysis details • preliminary results ( for ~140 fb-1 ) • Dalitz-plot analysis • summary JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  3. Mechanisms of BD(*)D(*)K decays b  cW - c c s + dd (uu) pair creation ( I ) through external W-emission amplitudes B+ D(*)0 D(*)+ K0 B0 D(*)- D(*)0 K+ ( II ) internal W-emission amplitudes (color-suppressed) B+ D(*)+ D(*)- K+ B0 D(*)0 D(*)0 K0 ( III ) external +internal W-emission amplitudes B+ D(*)0 D(*)0 K+ B0 D(*)- D(*)+ K0 22 decay modes + c.c JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  4. B  D(*)D(*)K : good place to explore spectroscopy: X  DD • cc-bar states above DD threshold scarcely known((3770) (4040) …) • molecular charmonia ( X(3872) ? ) , ccqq states, ccg hybrid states… Y  D(*)K from W-vertex • c s : L= 0 0-Ds(1970) 1-D*s(2112) well known L= 1 jP = 1/2+0+ DsJ± (2317) 1+ DsJ± (2457) seen, do not decay to DK ( chiral doublet toDs± Ds*± ) jP = 3/2+1+ Ds1± (2536) 2+ DsJ± (2573) not seen in B decays ( do chiral partners exist?) • charm deficit B  D(*) D(*) K : significant (~1/2) contribution to b ccs transitions precise BF’s measurements needed • B0 D(*)+ D(*)- K0Sto probe both sin2 and cos2 Physics motivations JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  5. Analysis details • at least 5 good tracks with abs(IP_dz)< 5cm abs(IP_dr)< 0.4cm • R2< 0.3 • K± : P(K/) > 0.4± : P(/K) > 0.1 electron veto: el_id < 0.95 • K0Sabs( M(+ -) - MKs ) < 15 MeV only good_Ks • 0 E > 50 MeV abs( M( ) -M0 ) < 15MeV • D±, D0 and D*±, D*0 reconstruction (N(D)>1 : p(D) < 2. GeVin (4S) system ) • B±, B0 reconstruction : all possible (22 + c.c) physical combinationsD(*)D(*)K B vertex fit: with IP and B lifetime constraints Mbc > 5.2 GeV -0.40 < E < 0.35 GeV JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  6. D(*) plots for ~ 11fb-1 (exp17) D0reconstruction for skimmed sample (with DDK candidate ) BF ~ 28% • vertex fit (refit 0 ) • M (DREC) cut: ± 20MeV • (D0 K0 : - 50MeV) • constraint_mass fit D0 K D0 K3 D0 K0 (doesn`t applied for these plots) D0 KsKK D0 Ks D0 KK JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  7. D(*) plots for ~ 11fb-1 (exp17) D± reconstruction BF ~ 15% • reconstruction procedure • like in D0 case D±Ks D±K D±KsK D±KK D±Ks0 D± JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  8. D(*) plots for ~ 11fb-1 (exp17) D*± reconstruction D*±  D0± BF ~ 68% (D*±  D± 0hopeless ) • vertex fit • (constraints :IP, B) • abs(M(D*)-M(D)-mPDG)< 2.5MeV D0 K D0 K3 D0 K0 D0 KsKK D0 KK D0 Ks JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  9. D(*) plots for ~ 11fb-1 (exp17) D*0 reconstruction • vertex fit • (constraints :IP, B) • refit 0 (vtx_constraint) • abs(M(D*)-M(D)-mPDG)< 5MeV D*0  D00 BF ~ 62% D0 Ks D0 K0 D0 K JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  10. Multi-candidates events treatment • more than 1 candidates in the same B sub-mode • multi D(*) candidates per event • D(*)D(*) combinations with different K`s ~3. B cand per event ( all sub-modes ) D, D* probabilities (LR): S(MD) S(MD), B(MD) parameterization from MD fit LR_D (MD) = + S(MD) B(MD) S(MD*) S(MD*), B(MD*) parameterization from MD*fit LR_D*(MD*) = + S(MD*) B(MD*) JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  11. Choice of the best B candidate B probability (LR_B) ( for each B decay sub-mode separately ) LR_B = LR_D(*) × LR_D(*) • best B candidate : with max LR_B • equal LR_B case ( B`s differ only in K ) : • larger K±_ID or better K0S mass candidate chosen S/(S+B) choice method “combines” both criteria: (M-MPDG)/ and S/B ratio LR_B used also for background discrimination ( very efficient ) JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  12. (external+internal W-emission) B+ D0D0K+ LR > 0.04 N/7.5MeV N/2MeV Plot for Mbc>5.27 GeV plot for abs(E)<25MeV E Mbc Fully reconstructed signal (from 2dimlikelihood fit) S=94.4 ± 13.0 eff= ( 4.80 ± 0.14 ) *10-4 BF = ( 1 .30 ± 0.18 ± 0.21 ) * 10-3 XNSIG_1 94.4±12.9 XE0_1 -0.32E-02± 0.11E-02 XEW_1 0.59E-02± 0.07E-02 XM0_1 5.2815± 0.28E-03 XMW_1 0.25E-02 ± 0.04E-02 JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  13. (external W-emission) B0 D-D0K+ LR > 0.01 Plot for Mbc>5.27 GeV N/7.5MeV N/2MeV plot for abs(E)<25MeV E Mbc Fully reconstructed signal (from 2dimlikelihood fit) S= 127.6 ± 15.3 eff= ( 5.70 ± 0.14 ) *10-4 BF = ( 1 .75 ± 0.21 ± 0.29 ) * 10-3 XNSIG_1 127.6±15.3 XE0_1 -0.19E-02± 0.09E-02 XEW_1 0.55E-02± 0.07E-02 XM0_1 5.2812± 0.39E-03 XMW_1 0.26E-02 ± 0.03E-02 JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  14. (external W-emission) B0 D*-D0 K+LR > 0.05 Plot for Mbc>5.27GeV Fully reconstructed signal (from 2-dim Mbc vs.E likelihood fit) N/7.5MeV XNSIG_1 86.9 ±10.6 XE0_1 -0.19E-02 ± 0.09E-02 XEW_1 0.69E-02 ± 0.09E-02 XM0_1 5.2807± 0.41E-03 XMW_1 0.30E-02 ± 0.03E-02 E Plot for abs(E)<25MeV N/2MeV eff= ( 2.84 ± 0.07 ) *10-4 BF = ( 2.02 ± 0.25 ± 0.34 ) * 10-3 S = 86.9 ± 10.6 Mbc JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  15. B+ D0D*0K+( right D*K flavor comb.)LR > 0.01 (ext+int) Plot for Mbc>5.265GeV N/7.5MeV Fully reconstructed signal (from 2-dimlikelihood fit) XNSIG_1 49.4±11.6 XE0_1 0.104E-02± 0.43E-02 XEW_1 0.18E-01 ± 0.04E-01 XM0_1 5.2819± 0.98E-03 XMW_1 0.40E-02 ± 0.08E-02 E Plot for abs(E)<45MeV N/2MeV S = 49.4 ± 11.6 Signif.= 7.0 eff= ( 0.64 ± 0.03) *10-4 BF = ( 5 .30 ± 0.93 ± 0.87) * 10-3 Mbc JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  16. B+ D0D*+K0sLR > 0.005 (ext) Plot for Mbc>5.27GeV Fit results for directly reconstr. signal (from 2-dim Mbc vs.E likelihood fit) N/7.5MeV XNSIG_1 40.2±10.1 XE0_1 -0.13E-02± 0.25E-02 XEW_1 0.11E-01± 0.03E-01 XM0_1 5.2808± 0.80E-03 XMW_1 0.28E-02 ± 0.07E-02 E Plot for abs(E)<25MeV N/2MeV S = 40.2 ± 10.1 Signif. = 7.5 eff= ( 1.48 ± 0.06) *10-4 BF = ( 1 .79 ± 0.45 ± 0.25) * 10-3 Mbc JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  17. B0 D*-D*0K+ LR > 0.0 (ext) Plot for Mbc>5.27GeV Fitting results (2dim fit) XNSIG_1 43.4±10.1 XE0_1 -0.34E-02 ± 0.74E-02 XEW_1 0.31E-01 ± 0.07E-02 XM0_1 5.2814± 0.84E-03 XMW_1 0.32E-02 ± 0.07E-02 E Plot for abs(E)<45MeV S = 49.4 ± 11.6 Signif.= 7.1 eff= ( 0.49± 0.03) *10-4 BF = ( 5 .82 ± 1.35 ± 0.96) * 10-3 Mbc JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  18. B0 D*-D*+K0s LR > 0.0 (ext+int) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  19. Dalitz plot for B+ D0D0K+ LR > 0.04 forsignal-box events:abs(E)<25MeV Mbc>5.27GeV Hatched histogram: Mbc sideband events abs(E+0.16)<50MeV Mbc<5.26GeV normalized to backgr. in pion_lost signal box M2 ( D0B D0 ) M2 ( D0K+ ) right M ( D0K+ ) right (3770) N/10MeV M ( D0B K+ ) wrong M ( D0B D0 ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  20. mass distr. for B+ D0D0K++missing for lostsignal-box events:abs(E+0.16)<50MeV Mbc>5.265GeV LR > 0.1 Hatched histogram: Mbc sideband events abs(E+0.16)<50MeV Mbc<5.26GeV normalized to backgr. in pion_lost signal box M ( D0K+ ) right N/10MeV M ( D0B D0 ) M ( D0B K+ ) wrong JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  21. B+ D0D0K+ (3770) • fitting B signal in DD, DK invariant mass bins inv. massdistributions without background • fitted B yield • PhaseSpace distr. (3-body MC) N / 25MeV M ( D0B D0 ) N / 50MeV N / 50MeV M ( D0K+ ) M ( D0BK+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  22. Dalitz plot for B0 D-D0K+ LR > 0.04 forsignal-box events:abs(E)<25MeV Mbc>5.27GeV Hatched histogram: Mbc sideband events abs(E+0.16)<50MeV Mbc<5.26GeV normalized to backgr. in pion_lost signal box M2 ( D0D-) M2 ( D0K+ ) M ( D0K+ ) N/10MeV M ( D0D- ) M ( D-K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  23. B0 D-D0K+ DsJ± (2573) ? DsJchiral partner??? N / 50MeV N / 50MeV M ( D0K+ ) SIG_1 15.3±5.6 M0_1 2.577± 0.014 MW_1 0.025± 0.007 SIG_2 32.5 ± 7.1 M0_2 2.717± 0.008 MW_2 0.029± 0.006 M ( D0K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  24. Dalitz plot for B0 D*-D0 K+ forsignal-box events:abs(E)<25MeV Mbc>5.27GeV LR > 0.005 Hatched histogram: Mbc sideband events abs(E)<80MeV Mbc<5.26GeV normalized to backgr. in signal box M2 ( D0K+) M2 ( D*-D0 ) M ( D0K+ ) also for LR > 0.01 ? N/10MeV M ( D*-K+ ) M ( D*-D0 ) M ( D*-K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  25. mass distr. for +missing for lostsignal-box events:abs(E+0.16)<50MeV Mbc>5.265GeV B0 D*-D0 K+ LR > 0.05 Ds1 ? Hatched histogram: Mbc sideband events abs(E+0.16)<50MeV Mbc<5.26GeV normalized to backgr. in pion_lost signal box M ( D0K+ ) N/10MeV M ( D*-D0 ) M ( D*-K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  26. B0 D*-D0K+ N / 50MeV M ( D*-D0 ) N / 50MeV N / 50MeV M ( D*-K+ ) M ( D0K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  27. Dalitz plot for B+ D0D*+K0s LR > 0.002 forsignal-box events:abs(E)<25MeV Mbc>5.27GeV Hatched histogram: Mbc sideband events abs(E)<80MeV Mbc<5.26GeV normalized to background in signal box M2 ( D*+K0s ) M2 ( D*+D0B ) M ( D*+K0s ) N/10MeV M ( D*+D0B ) M ( D0K0s ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  28. mass distr. for +missing for lostsignal-box events:abs(E+0.16)<50MeV Mbc>5.265GeV B+ D0D*+K0s LR > 0.05 Hatched histogram: Mbc sideband events abs(E+0.16)<50MeV Mbc<5.26GeV normalized to backgr. in pion_lost signal box Ds1 ? M ( D*+K0s ) N/10MeV M ( D*+D0B ) M ( D0B K0s ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  29. B+ D0D*+K0s N / 100MeV N / 50MeV M ( D*+K0s ) M ( D*+D0B ) for  signal lost box N / 50MeV N /150MeV M ( D*+K0s ) M ( D0Ks ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  30. Dalitz plot for B+ D0D*0K+ ( both D*0K flavor comb.) forsignal-box events:abs(E)<45MeV Mbc>5.265 GeV LR > 0.01 Hatched histogram: Mbc sideband events abs(E)<80MeV Mbc<5.26GeV normalized to backgr. in signal box M2 ( D*0K+ ) M2 ( D*0 D0B ) M ( D*0K+ ) right N/10MeV 3.87GeV M ( D*0 D0B ) M ( D0K+ ) right JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  31. mass distr. for B+ D0D*0K++missing for lostsignal-box events:abs(E+0.16)<50MeV Mbc>5.265GeV LR > 0.01 Hatched histogram: Mbc sideband events abs(E+0.16)<50MeV Mbc<5.26GeV normalized to backgr. in pion_lost signal box M ( D*0K+ ) right N/10MeV M ( D*0D0B ) M ( D0K+ ) right JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  32. B+ D0D*0K+ N / 50MeV N / 50MeV M ( D*0 K+ ) M ( D0B D*0 ) for  signal lost box N / 50MeV N / 50MeV M ( D0K+ ) M ( D*0 K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  33. Dalitz plot for B0 D*-D*0K+ LR > 0.0 for signal box: Mbc>5.27GeV abs(E)<45MeV ~10 events at the threshold at 2.54 GeV come from Ds1± (2536)-> D*0K± ? M2 ( D*0K+) M2 ( D*-D*0 ) M ( D*0K+ ) M ( D*-D*0 ) M ( D*-K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  34. B0 D*-D*0K+ N / 100MeV N / 50MeV M ( D*-D*0 ) M ( D*0K+ ) N / 50MeV M ( D*-K+ ) JOLANTA BRODZICKA B  D(*)D(*)K November 05, 2003

  35. LR_D*± vs. M plots LR_D0 vs. D_mass plots D0 K D0 K3 D0 K0 D0 Ks D0 KK D0 KsKK JOLANTA BRODZICKA B  D(*) D(*) K November 05, 2003

  36. S(MD) LR_D (MD) = + S(MD) B(MD) best B candidate choice method (see my December ICPV talk for more details) S(MD), B(MD) parameterization from MD fit D probability : LR_B = LR_D1× LR_D2 B probability for B± D0D0BK± : • best B candidate : with max LR_B LR_D1vs. LR_D2 plots choice method efficiency(for (kpi)(kpi) ) best = 82 % (estimated from rejected MC events DE, Mbc distributions and correlations between accepted and rejected B candidates ) for B± D0D0BK± (kpi)(kpi) reconstr. eff is 15% efficiency lost due to B_best choice method is 0.9% (kpi)(kpi) (kpi)(no kpi) JOLANTA BRODZICKA B  DDK March 12, 2003

  37. LR_B cut (good for bckg reduction and s/b improvement) S / B S / sqrt (S + B ) LR_D1 * LR_D2 cut LR_D1 * LR_D2 cut Signal MC: B±  D0 D0B K± ( for BF = 1.5 * 10-3 ) Background: B±  D0 D0B K± data sideband JOLANTA BRODZICKA B  DDK March 12, 2003

  38. LR_B cut efficiency LR_B cut: good for background reduction and s /b ratio improvement Background reduction (DATA) all Efficiency reduction (signal MC ) LR_D1 * LR_D2 cut LR_D1 * LR_D2 cut Background: B±  D0 D0B K± sideband Signal MC: B±  D0 D0B K± for all D0D0B combinations JOLANTA BRODZICKA B  D(*) D(*) K December 12, 2002

  39. Possibility of Ds1+(2536) detection Generated 20K MC decays: B+ Ds1+(2536) D0B(Ds1)=5MeV Ds1+(2536)  D*0 K+ D0,D0B K LR > 0.01 For directly reconstr. signal: B+ D*0 K+ D0B For partially reconstr. signal: B+ D0 K+ D0B + missing pion N140 M0 2536  7.1 N1420 M0 2393  5.0 N/1MeV N/1MeV M ( D*0K±) M ( D0K±) -143MeV shift JOLANTA BRODZICKA B  D(*)D(*)K October 10, 2003

  40. Possibility of X(3872) detection (if any  ) Generated 20K MC decays: B+ X(3872) K+(X)=5MeV Mmin=M(D*0+D0) X(3872)  D*0D0B D0,D0B K LR > 0.01 For directly reconstr. signal: B+ D*0 D0B K+ For partially reconstr. signal: B+ D0 D0BK+ + missing pion N/1MeV N1100 N3400 N/1MeV M ( D*0D0B) M ( D*0D0B) JOLANTA BRODZICKA B  D(*)D(*)K October 10, 2003

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