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D 0 K + mass spectra for:

D 0 K + mass spectra for:. B +  D 0 D 0 K + B 0  D - D 0 K + B 0  D* - D 0 K +. for  25 0fb -1 (exp7-3 7 ). Outline : B +  D 0 D 0 K + B 0  D - D 0 K + B 0  D* - D 0 K + for  250fb -1 Dalitz plots and projections B ackground subtracted M(D 0 K + ) distributions

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D 0 K + mass spectra for:

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  1. D0K+mass spectra for: • B+ D0D0K+ • B0 D-D0K+ • B0 D*-D0K+ for 250fb-1 (exp7-37) • Outline : • B+ D0D0K+B0 D-D0K+B0 D*-D0K+ for 250fb-1 • Dalitz plots and projections • Background subtracted M(D0K+) distributions • DsJ(2573) & DsJ(2720) • Angular distrbutions Jolanta Brodzicka, Henryk Palka INP Krakow ICPV meeteing August 5, 2004

  2. B+ D0D0K+ for Mbc >5.273 GeV N/7.5MeV E for E<18MeV N/2.5MeV Mbc LR > 0.04 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 Fit result: S/B=0.55 S = 145.2±17.3 G0(E) = -0.27E-02± 0.07E-02 GeV  (E) = 0.50E-02± 0.06E-02 GeV G0(Mbc) = 5.2814± 0.0003 GeV  (Mbc) = 0.24E-02 ± 0.02E-02 GeV Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  3. for Mbc >5.273 GeV N/7.5MeV E for E<18MeV N/2.5MeV Mbc B0 D-D0K+ LR > 0.01 Fit result (for fully reconstructed region): S/B=0.46 S = 191.3±19.2 G0(E) = -0.17E-02± 0.07E-02 GeV  (E) = 0.57E-02± 0.06E-02 GeV G0(Mbc) = 5.2808± 0.0003GeV  (Mbc) = 0.25E-02 ± 0.02E-02 GeV Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  4. for Mbc >5.273 GeV N/7.5MeV E for E<30MeV N/2.5MeV Mbc B0 D*-D0K+ LR > 0.005 Fit result (for fully reconstructed region): S/B=0.82 S = 222.4 ±21.5 G0(E) = -0.36E-02± 0.09E-02 GeV  (E) = 0.99E-02± 0.10E-02 GeV G0(Mbc) = 5.2814± 0.0003GeV  (Mbc) = 0.26E-02 ± 0.02E-02 GeV Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  5. BF calculations based on 140fb-1 Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  6. B+ D0D0K+ DsJ(2573) (4160) M2( D0D0) (3770) M( D0K+) M( D0D0 ) Dalitz plot and projections for LR > 0.04 for signal-box events : Background:elliptical strip 6 to 10 in Mbc, E, surrounding the signal region Mbc > 5.273 GeV E<16 MeV (~3 ) M2( D0K+) (4160) (3770) DsJ(2720) DsJ(2720) reflection (4040) N / 20MeV (4160) reflection possible DsJ(2720) (3770)reflection DsJ(2573) N / 20MeV N / 20MeV M( D0 K+) Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  7. 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(2720) N / 20MeV M2( D0D- ) M2( D0K+) M( D-D0 ) DsJ(2720) DsJ(2573) N / 20MeV N / 20MeV M( D0K+) M( D-K+) Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  8. for signal-box events : Mbc > 5.273 GeV E<30 MeV (~3 ) Dalitz plot and projections B0 D*-D0K+ LR > 0.005 Background N / 20MeV M2( D0K+) DsJ(2720) DsJ(2573) M2( D0D*- ) M( D*-D0 ) DsJ(2573) DsJ(2720) N / 20MeV N / 20MeV M( D*-K+) M( D0K+) Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  9. B+ D0D0K+ fitted Signal with error M(D0K+) background subtracted distributions 2dim Mbc vs.E fits in M( D0K+ ) bins B signal in M( D0K+) bins • peak at 2.720 GeV seen, no DsJ(2573) • (3770) region removed: M(D0D0)>3845 Signal / 50MeV • is the (4160) contributing to 2720 peak? • DsJ(2573) • andDsJ(2720) • observed • DsJ(2573) • andDsJ(2720) • observed B0 D*-D0K+ B0 D-D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D0K+) Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  10. (3770) (4160) B+ D0D0K+ Signal / 50MeV Signal / 50MeV (4160) M(D0D0) M(D0D0) M(D0D0) background subtracted distribution for M( D0K+ )peak at 2.7GeV contributed to the (4160)and vice versa (they overlap on Dalitz plot) To estimate of the (4160)contribution to the 2.7GeV peak: M(D0D0) for M(D0K+) > 2.9GeV ( ≡ ½ of the (4160)helicity distr.) (4160)contribution to the 11± 5 events Reflection shape: according to cos2 angular distribution of the polarized (4160) DsJ(2720) Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  11. B+ D0D0K+ B+ D0D0K+ N = 67.7± 12.0 M = 2700± 15 MeV  = 162± 44 MeV N = 65.1± 8.4 M = 2710± 7 MeV  = 112± 22 MeV fitted B Signal M( D0K+) – M(D0K+) „right” - ”wrong” flavour combinations to remove reflections from charmonium states DsJ(2720) Fits to background subtracted D0K+ mass spectra (1) • resonances described by non-relativistic Breit-Wigners • Phase Space (nonresonant component) is described by linear function Signal / 50MeV Signal / 50MeV M( D0K+) non-resonant component + reflection from (4160) DsJ(2720) Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  12. fitted B Signal N = 32.5± 7.9 M = 2573 MeV fixed  = 15 MeV fixed N = 113.7± 14.4 M = 2710 MeV fixed  = 110 MeV fixed N = 12.3 ± 3.6 M = 2573MeV fixed  = 15 MeV fixed N = 113.2± 19.0 M = 2710 MeV fixed  = 110 MeV fixed DsJ(2573) DsJ(2573) DsJ(2720) DsJ(2720) Fits to background subtracted D0K+ mass spectra (2) • resonances described by non-relativistic Breit-Wigners • DsJ(2573)the convolution BW  G(=50MeV) is used • Phase Space (nonresonant component) is described by linear function B0  D-D0K+ B0  D*-D0K+ Signal / 50MeV Signal / 50MeV M( D0K+) M( D0K+) Fit variants: Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  13. K+ D0K+  B D D0 fitted B Signal corrected for acceptance Angular distribution Helicity angle  : angle between K+momentum in D0K+rest frame and D0K+momentum (the boost direction) in B rest frame cosdistribution obtained using 2-dim Mbc vs.E fit ineach cosbin(to subtract background) DSJ(2573) region: B0  D-D0K+ signal-box 2.54 < M(D0K+) < 2.6 GeV (30 MeV window ) Acceptance for MC: B0  D-DsJ(2573)(K)(K) For DsJ(2573)J=2 Ang.distribution:9cos4  - 6cos2  + 1 (previously 3-body D-D0K+MC used) Eff. corrected signal cos Compatible withJ=2 cos Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  14. fitted B Signal corrected for acceptance Angular distribution (2) Acceptance for signal MC B+  D0 DsJ(2720)(K)(K) For DsJ(2720)J=2 assumed Ang.distribution:9cos4  - 6cos2  + 1 (previously 3-body D0D0K+MC used) DsJ(2720) region: B DD0K+ signal-box 2.64 < M(D0K+) < 2.8 GeV (80MeV window ) B+ D0D0K+ Eff. corrected signal cos cos Acceptance for signal MC B0  D-DsJ(2720)(K)(K) For DsJ(2720)J=2 assumed (previously 3-body D-D0K+MC used) B0  D-D0K+ Eff. corrected signal cos cos Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  15. Backup slides Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  16. 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 Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  17. D0K D0K3 D0K0 S(MD) LR_D ( MD )= MD MD S(MD) B(MD) + MD D± K D±Ks • best Bcandidate : withmax LR_B • equal LR_B case: larger K±_ID candidate chosen MD MD Multi-candidates events treatment Dplots for ~11fb-1after preselection p(D) < 2GeVin (4S) system D probabilities (LR_D ): LR_D LR_D S(MD), B(MD)parameterization from fits todata (inclusively reconstructed D0, D± in each decaymode separately ) LR_D B probability ( LR_B ): LR_B = LR_D1× LR_D2 LR_D LR_D LR_B used also for backgrounddiscrimination Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  18. B+ D0D0K+ M( D0K+) M( D0D0 ) Background subtracted mass distributions wrong flavour comb. Signal / 50MeV Signal / 50MeV Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  19. fitted B Signal Angular distribution uncorrected for acceptance DSJ(2573) region: B0  D-D0K+ signal-box 2.54 < M(D0K+) < 2.6 GeV B0  D-D0K+ cos DsJ(2720) region: B DD0K+ signal-box 2.64 < M(D0K+) < 2.8 GeV B0  D-D0K+ B+ D0D0K+ cos cos Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

  20. 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 Jolanta Brodzicka, Henryk PalkaINP Krakow ICPV August 05, 2004

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