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J OLANTA B RODZICKA

Doubly charmed B decays. B  D (*) D (*) K. ( for ~140 fb -1 ). J OLANTA B RODZICKA. BGM Nov 21, 2003. I NSTITUTE OF N UCLEAR P HYSICS , K RAKOW. b  c c s transition “ wrong-sign” D production physics motivations analysis method

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J OLANTA B RODZICKA

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  1. Doubly charmed B decays B D(*)D(*)K ( for ~140 fb-1 ) JOLANTA BRODZICKA BGMNov 21, 2003 INSTITUTEOF NUCLEAR PHYSICS, KRAKOW

  2. b  c c stransition “wrong-sign” D production • physics motivations • analysis method • preliminary results ( for ~140 fb-1 ): signals and BF’s D(*)KandD(*)0D0mass spectra ( search for X(3872)→D*0D0) • summary and conclusions B0 D-D0K+ B+ D0D0K+ B0 D*-D0 K+ B+ D0D*0K+ B0 D*-D*0K+ B+ D0D*+K0s JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Outline B+ D*-D*+K0s (no BF yet)

  3. Leading quark diagrams B D(*)D(*)K decays B+ D(*)0 D(*)+ K0 B0 D(*)- D(*)0 K+ B+ D(*)+ D(*)- K+ B0 D(*)0 D(*)0 K0 B+ D(*)0 D(*)0 K+ B0 D(*)- D(*)+ K0 JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 b  cW - c c s + dd (uu) pair creation ( I ) through external W emission amplitudes ( II) internal W emission amplitudes (color-suppressed) ( III ) external +internal W emission amplitudes 22 decay modes + c.c

  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?) • measurement of the BF’s and their ratios: important for understanding of factorization, color suppression and ‘charm deficit ’ in B decays • B0 D(*)+ D(*)- K0Sto probe both sin21 and cos21 Physics motivations JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003

  5. Analysis details JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 accepted events with:R2< 0.3 tracks with:abs(IP_dz)< 5cmabs(IP_dr)< 0.4cm K± :P(K/) > 0.4± : P(/K) > 0.1electron veto:el_id < 0.95 K0S :abs( M(+ -) - MKs ) < 15MeVonly good_K0s 0: E > 50 MeVabs( M( ) -M0 ) < 15MeV • D(*) reconstruction D0K, K3, K0, Ks, KK BF ~ 28%of total D±K, Ks, KK, KsK BF ~ 12%of total abs(M(D)-M(DPDG) ) < 20MeV ( D0 K0: -50MeV ) vertex fit (cl > 0.) and mass constraint fit applied, p(D) < 2GeVin (4S) system D*± D0±abs(M(D*±)-M(D)-mPDG) < 2.5MeV D*0 D00abs(M(D*0)-M(D)-mPDG) < 5MeV vertex fit (cl > 0.)applied • Breconstruction : all(22 + c.c)physical combinationsD(*)D(*)K B vertex fit:with IP and B constraints Mbc> 5.2 GeV -0.40 < E < 0.35 GeV

  6. D(*) plots for ~11fb-1 sampleafter preselection S(MD) LR_D ( MD )= S(MD) B(MD) + + S(MD*) LR_D*( MD* )= S(MD*) B(MD*) JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Multi-candidates events treatment p(D) < 2GeVin (4S) system • > 1 candidates in the same B sub-mode • several D(*) candidates per event • D(*)D(*) comb. with different K`s D, D* probabilities (LR): LR LR MD MD LR LR S(MD), B(MD) and S(MD*), B(MD*) parameterization from MD and MD*fits to data ( “inclusively” reconstr. D(*) ) MD* MD*

  7. JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 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

  8. B+ D0D0K+ LR_D0 * LR_D0 cut B+ D0D0K+ B+ D0D0K+ B+ D0D0K+ JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 LR_B cut (good for background reduction and S/B improvement) Data for Mbc>5.27GeV N/7.5MeV Signal MC no LR cut S / sqrt (S + B ) N/7.5MeV LR > 0.04 LR > 0.1 N/7.5MeV Signal MC: ( for BF=1.5 * 10-3 ) Background:Mbcsideband E

  9. plot for Mbc >5.27 GeV N/7.5MeV E plot for abs(E)<25MeV N/2MeV For fully reconstr. signal: S= 127.6 ± 15.3 Stat_signif.= 10.9 eff= ( 6.98 ± 0.14 ) *10-4 BF = ( 1 .68 ± 0.20 ± 0.25 ) * 10-3 Mbc JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 B0 D-D0K+ & a little bit more on method LR > 0.01 My fitting method: 2dimMbcvs.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 2 lost  lost All parameters are kept free. They are in agreement with MC Yields for 3 regions: S = 127.6 ± 15.3 fully reconstr. S = 728.7 ± 53.1 partially reconstr.: B0 D-D*0 K+ B+ D-D*+K+ B0 D*-D0K+ S2 = 972.8 ± 68.0 partially reconstr.: B0 D*-D*0 K+ B+ D*-D*+ K+

  10. plot for abs(E)<25MeV N/2MeV plot for Mbc >5.27 GeV N/7.5MeV Mbc E B+ D0D*0K+LR > 0.01 plot for abs(E)<45MeV plot forMbc >5.265GeV N/7.5MeV N/2MeV E Mbc JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 B+ D0D0K+ LR > 0.04 S = 94.4 ± 13.0 Stat_signif.= 9.3 eff= ( 4.80 ± 0.14 ) *10-4 BF = ( 1 .30 ± 0.18 ± 0.21 ) * 10-3 S = 49.4 ± 11.6 Stat_signif.= 7.0 eff= (0.39 ± 0.03 ) *10-4 BF = ( 8.84 ± 1.56 ± 1.5) * 10-3

  11. B0 D*-D*0K+LR > 0.0 plot for Mbc>5.27GeV plot for abs(E)<25MeV plot for abs(E)<45MeV plot for Mbc>5.27GeV N/2MeV S = 43.4 ± 10.1 Stat_signif.= 7.1 eff= (0.34± 0.03) *10-4 BF = ( 8.44 ± 1.97 ± 1.33) * 10-3 N/7.5MeV E Mbc E Mbc JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 B0 D*-D0 K+LR > 0.05 S = 86.9 ± 10.6 Stat_signif.= 12.8 eff= (1.91 ± 0.07 ) *10-4 BF = ( 2.99 ± 0.37 ± 0.53 ) * 10-3

  12. B+ D0D*+K0sLR > 0.005 B0 D*-D*+K0sLR > 0.0 plot for abs(E)<25MeV S = 40.2 ± 10.1 Stat_signif. = 7.5 plot for Mbc>5.27GeV N/7.5MeV N/2MeV eff= (0.46 ± 0.06 ) *10-4 BF = ( 5.80 ± 1.46 ± 1.18) * 10-3 S = 248.4 ± 22.6 D0(-,0,γ)D*+K0s (maybe can be useful for time dependent analysis) Mbc E JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 S = 17. v. clean (no LR-cut used) (good_K0S used, looser selection should give more)

  13. __ __ __ __ JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 BF summary NS ∑ (eff*BFsec) [10-4] BF [10-3] B+→ D0 D0 K+ 94.4 ± 13.0 4.99 1.25 ± 0.17 ± 0.20 B0→ D- D0 K+ 127.6 ± 15.3 6.98 1.68 ± 0.20 ± 0.25 B0→ D*- D0 K+ 87.0 ± 10.6 1.91 2.99 ± 0.37 ± 0.53 B+→ D0 D*+ K0 40.2 ± 10.1 0.46 5.80 ± 1.46 ± 1.18 B0→ D*- D*0 K+ 43.4 ± 10.1 0.34 8.44 ± 1.97 ± 1.33 B+→ D0 D*0 K+ 49.4 ± 11.6 0.39 8.84 ± 1.56 ± 1.50 B+→ D*0 D0 K+ 77.9 ± 13.7 (49.4 ± 11.6) 0.39 5.10 ± 0.90 ± 0.75

  14. Look for resonant structure: e.g.Dalitz plot & projections for M ( D-K+ ) fitted S (plotted above bckg) fitted B Mbcsideband normalized to background in signal box JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 B0 D-D0K+ forsignal-box events: abs(E) < 25 MeV Mbc > 5.27 GeV M(D0D- ) M( D0K+ ) M ( D0D- ) 2dim Mbcvs.E fit in M( D0K+ ) bins (to filter out bckg from Dalitz-plot projection) N / 10MeV S + B / 50MeV M( D0K+ ) M( D0K+ ) ( fitted S+B gives good description of data ) Sbins - Sglobal ~1

  15. D0K+resonant structure S / 50MeV PS corrected for (3770)D0D0 contribution) N = 8.1± 2.3 N = 30.2± 8.4 N = 15.1± 5.1 N = 80.2± 11.7 N = 30.2± 5.7 S / 50MeV M= 2.714 ± 0.008 GeV M= 2.723 ± 0.014 GeV M= 2.720 GeV fixed M= 2.728 ± 0.013 GeV M= 2.573 GeV fixed DSJ(2573) = 0.080± 0.020 GeV = 0.084± 0.029 GeV = 0.080 GeV fixed = 0.080 GeV fixed = 0.015GeV fixed B+ D*0D0K+ S / 50MeV SIGNAL with subtracted bckg JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 S / 50MeV B+ D0D0K+ M( D0K+ ) - M( D0K+ ) “right”-”wrong” flavor comb B0 D-D0K+ Peak @ ~2730 sth new! fitted functions: BW +&Phase Space shape from 3body signal MC with free normalization (to describe non-resonant component) M( D0K+ )

  16. Supporting evidence in D*K ? Partially reconstructed: B  D0D*0K+ +  lost N = 50.7± 15.3 N = 27.7± 8.0 N = 3.8± 1.6 M= 2.743 ± 0.009 GeV M= 2.613 ± 0.008 GeV M= 2.536 GeV fixed DS1(2536) ? = 0.050± 0.026 GeV = 0.005 GeV fixed (exp.resol) = 0.039± 0.014 GeV B+ D0D*+K0s S / 50MeV B  D(*)D*+K0s S / 50MeV Partially reconstructed: B+ D0D*+K0s+  lost PS for 3body MC M( D*0K+ ) SIGNAL with subtracted bckg JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 S / 25MeV B D(*)D*0K+ Fitted:G+BW+BW+&PS M( D*0K+ ) B+ D0D*0K+ S / 50MeV B0 D*-D*0K+ S / 50MeV M(D*+K0s)

  17. B+ D0D*0K+ S / 25MeV N = 25.0± 5.8 M = 3.770 GeV fixed  = 0.0253GeV fixed M ( D0D0) M ( D0 D*0) Phase Space shape from 3body signal MC JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Other results B+ D0D0K+ N / 50MeV Search for X(3872)→D0D*0 confirmation of (3770)→D0D0 (in 10MeV bin) : 2 evts observed, 1 evt expected bckg in B+ D0D0K+ 90% UL by counting method (Feldman-Cousins) BF(B+→K+X(3872))xBF(X(3872)→ D0D*0) <2.37x10-4 fitted functions: BW +sqrt(1-thr/x)*POL_3 BF(B+→K+ (3770))xBF((3770)→ D0D0) = ( 3.0 ± 0.7 ± 0.5 )x10-4

  18. B+ D0D0K+ B+ D0D*0K+ B+ D0D*+K0s JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Summary • I have shown preliminary results ( for ~140 fb-1 ): signals and BF’s for following channels: I studied D(*)KandD(*)0D0mass spectra: B0 D-D0K+ B0 D*-D0 K+ B0 D*-D*0K+ B+ D*-D*+K0s (no BF yet) X D0 K+@ ~2730 MeV and width ~80MeV observed (sth new !) inB0 D-D0K+ B+ D0D0K+ B+ D0D*0K+ evidence >3 for DsJ(2573) D0 K+in B0 D-D0K+ 90% UL BF(B+→K+X(3872))xBF(X(3872)→ D0D*0)<2.37x10-4 (3770)→D0D0in B+ D0D0K+ confirmed

  19. JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Backup slides

  20. JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 BF systematic error decomposition per mode

  21. _ _ _ _ JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 BF comparison with other measurements

  22. JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 BF systematic error contributions • negligible contributions from selection cuts (wide mass window cuts, no vtx cuts)

  23. JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Mbc&E “movie” from 2dim Mbcvs.E fit in M( D0K+ ) 50MeV bins for B0 D-D0K+signal 2.35 < M( D0K+ ) < 2.55 GeV 2.55 < M( D0K+ ) < 2.75 GeV 2.75 < M( D0K+ ) < 2.95 GeV

  24. JOLANTA BRODZICKA B  D(*) D(*) K BGMNov 21, 2003 Mbc&E “movie” from 2dim Mbcvs.E fit in M( D0K+ ) 50MeV bins for B0 D-D0K+signal 2.95 < M( D0K+ ) < 3.15 GeV 3.15 < M( D0K+ ) < 3.35 GeV

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