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Resonances in decay for 400fb -1 DC Meeting April 10th, 2006 J.Brodzicka, H.Palka INP Kraków J.Brodzicka, H.Palka INP Kraków B + D 0 D 0 K + B + D 0 D 0 K +
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Dalitz plot projections for with 20MeV binning Background B + D 0 D 0 K + For 1.5 E-Mbc signal region LR > 0.01 J.Brodzicka, H.Palka INP Krakow DC February 6th, 2006 D sJ (2700) is not split up no significant narow states are seen besides (3770)
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband no LR cut no LR cut D mass sideband: |M(D) - 1.865 GeV| >15 MeV (~2σ) D mass sideband: |M(D) - 1.865 GeV| >15 MeV (~2σ) for M bc > 5.273 GeV (3 ) for E <20MeV (3 ) both D’s from mass sideband at least one D from mass sideband no peaking background
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 for M bc >5.277GeV (1.5 ) for E <10MeV (1.5 ) both D from mass sideband at least one D from mass sideband B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband
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Two-body mass distributions for B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 one D from mass sideband for M bc > 5.273 GeV (3 ) and E <20MeV (3 ) Mass spectra shapes consistent with background estimated from E-M bc sideband
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 both D from mass sideband for M bc > 5.273 GeV (3 ) and E <20MeV (3 ) Two-body mass distributions for B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 for M bc > 5.277 GeV (1.5 ) and E <10MeV (1.5 ) one D from mass sideband Two-body mass distributions for B + D 0 D 0 K + candidates with D 0 (’s) from the mass sideband
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for Mbc > 5.277GeV and E <10 MeV ( 1.5 signal region ) J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 Dalitz plot for corrected for acceptance ( with correction conserving number of events observed ) B + D 0 D 0 K + D sJ (2700) ~2.5 GeV
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Dalitz plot for corrected for acceptance ( scaled to BF(B + D 0 D 0 K + ) by effective efficiency obtained ) J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 for Mbc > 5.277GeV and E <10 MeV ( 1.5 signal region ) B + D 0 D 0 K +
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 Mass distributions corrected for acceptance (using large ~700K B + D 0 D 0 K + MC sample) Events from 1.5 E-Mbc signal region Background from 6 < d <10 strip surrounding the E-Mbc signal region
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 Background-free invariant mass distributions corrected for acceptance B signal in mass bins obtained from 2-dim M bc - E fits in two-body inv. mass bins fitted B Signal corrected for acceptance
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Dalitz plots for various decay models for J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 B + D 0 D 0 K + MC studies based on the relative contributions from the resonant components and 3-body decay obtained from data analysis (non coherent approach) no interference max constructive interf. D sJ (2700) and (4160) max destructive interf. D sJ (2700) and (4160) Generated distributions How interference between D sJ (2700) and (4160) (states crossing in the Dalitz plot) influences the D sJ parametres
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 non-coherent approach no interference max constructive interf. = 0 between D sJ (2700) and (4160) max destructive interf. = 180 between D sJ (2700) and (4160) Comparison of mass spectra in various decay models for B + D 0 D 0 K + Generated distributions
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 Dalitz plots for various decay models for B + D 0 D 0 K + Reconstructed distributions no interference max constructive interf. D sJ (2700) and (4160) max destructive interf. D sJ (2700) and (4160)
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 non-coherent approach no interference max constructive interf. between D sJ (2700) and (4160) max destructive interf. between D sJ (2700) and (4160) Comparison of mass spectra in various decay models for B + D 0 D 0 K + Reconstructed distributions
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 non-coherent approach no interference max constructive interf. between D sJ (2700) and (4160) max destructive interf. between D sJ (2700) and (4160) Comparison of mass spectra in various decay models with data distributions data interference effects do not influence the 2-body mass distributions substantially the 2-body mass distributions substantially decay model is not decided
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Interference related systematics on D sJ parameters J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 (to remove (3770) reflection from high M( D 0 K + ) region) for M(D 0 D 0 )>3.85 GeV BW + MC predicted (4160) reflection + non-resonant component described by 3-body MC no interference max constructive interf. max destructive interf. Uncertainty on: Yield: +4 % M: +3 -8 MeV Γ: +36 -30 MeV Fits like in data analysis:
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J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006 1 - strongly favoured Comparison with the D sJ (2700) spin hypotheses: J=1 2 /n.d.f = 6.7/5 ~cos 2 θ J=2 2 /n.d.f = 249.9/5 ~(1-3cos 2 θ) 2 J=0 2 /n.d.f = 184.7/4 flat Angular distribution in the DsJ(2700) helicity frame fitted B Signal corrected for acceptance D sJ (2700) region: 2.57 < M(D 0 K + ) < 2.84 GeV
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Backups J.Brodzicka, H.Palka INP Krakow DC April 10th, 2006
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Dalitz plot and projections for Background: elliptical strip 6 to 10 in Mbc, E, surrounding the signal region B + D 0 D 0 K + For Mbc > 5.277GeV E <10 MeV ( 1.5 signal region ) LR > 0.01 J.Brodzicka, H.Palka INP Krakow DC February 6th, 2006 (4160) (3770) D sJ (2700) D sJ (2700) (3770) (4160) D sJ (2700) (3770) (4160) (3770) (4160) D sJ (2700)
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J.Brodzicka, H.Palka INP Krakow DC February 6th, 2006 Background-free invariant mass distributions Background-free invariant mass distributions 2-dim M bc - E fits in 2-body inv. mass bins B signal in mass bins D sJ (2700) + (4160) reflection (4160) + D sJ (2700) reflection (3770) Background-free mass spectra are very consistent with the Dalitz-plot projections over the estimated background. fitted B Signal
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Estimation of the resonance contributions (4160) (3770) D sJ (2700) (to remove (3770) reflection from high M( D 0 K + ) region) for M(D 0 D 0 )>3.85 GeV Lower curve: MC predicted (4160) reflection + non-resonant component described by 3-body MC for (4160) in ½ helicity distr: 24 ± 11 events (~2σ) (for 2nd half helicity distr: 20% smaller efficiency) Breit Wigner functions + threshold function D sJ (2700) parameters consistent with previous estimations Z (3930) J.Brodzicka, H.Palka INP BAM February 27th, 2006 Non-resonant component yield : 47 ± 32
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Contributions from quasi-two-body components: (normalized to measured yields and superimposed by adding histograms) B+ (4160) K+ B+ (3770) K+ B+ D 0 D sJ + (2700) Explanation of 2-body mass spectra Shapes predicted by MC simulations D sJ + (2700), (3770) are not the full story, but the ‘fit’ is acceptable J.Brodzicka, H.Palka INP BAM February 27th, 2006
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