120 likes | 223 Vues
Doubly charmed B decays. B D (*) D (*) K. D (*) K resonant structure. ( for ~140 fb -1 ). J OLANTA B RODZICKA. DC March 03, 2004. INP, K RAKOW. D 0 K + resonant structure (shown @BGM). B + D 0 D 0 K +. S / 50MeV. PS corrected for (3770) D 0 D 0 contribution).
E N D
Doubly charmed B decays B D(*)D(*)K D(*)K resonant structure ( for ~140 fb-1 ) JOLANTA BRODZICKA DCMarch 03, 2004 INP, KRAKOW
D0K+resonant structure(shown @BGM) B+ D0D0K+ S / 50MeV PS corrected for (3770)D0D0 contribution) N = 80.2± 11.7 N = 15.1± 5.1 N = 30.2± 5.7 N = 8.1± 2.3 N = 30.2± 8.4 S / 50MeV M= 2.714 ± 0.008 GeV M= 2.573 GeV fixed M= 2.728 ± 0.013 GeV M= 2.723 ± 0.014 GeV M= 2.720 GeV fixed DSJ(2573) = 0.080 GeV fixed = 0.080 GeV fixed = 0.084± 0.029 GeV = 0.080± 0.020 GeV = 0.015GeV fixed B+ D*0D0K+ S / 50MeV SIGNAL with subtracted bckg JOLANTA BRODZICKA B D(*) D(*) K BGMNov 21, 2003 S / 50MeV 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+ )
fitted signal (plotted above bckg.) fitted background JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 signal box events B0 D-D0K+ B0 D-D0K+ LR>0.01 2dim E,Mbcfit inD0K+ mass bins to subtract background Fit only forE > - 75 MeV Good description of data also for high DK mass region N/50MeV M( D0K+ ) S + B / 50MeV M( D0K+ )
SIGNAL with subtracted bckg JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 B0 D-D0K+ 2dim fit inD0K+ mass bins for various LR cut LR > 0.005 LR > 0.01 (shown before) LR > 0.04 S/50MeV
Bckgr : Mbc sideband JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 Dalitz plot & projections for B0 D-D0K+ signal-box events LR > 0.04 N / 25MeV M(D0D- ) M( D0K+ ) N / 25MeV N / 25MeV
LR > 0.04 LR > 0.01 N / 25MeV Bckgr : E sideband below signal box N / 25MeV Bckgr : Mbc sideband JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 M( D0K+ )for B0 D-D0K+
M( D0K+ )for B+ D0D0K+ Bckgr : E sideband below signal box Bckgr : Mbc sideband JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 LR > 0.04 LR > 0.1 N / 25MeV N / 25MeV
SIGNAL with subtracted bckg ( efficiency corrected) Background ( after MC eff. corr): ~ flat JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 Angular distribution B0 D-D0K+ for2.54 <M( D0K+ ) < 2.6 GeV DSJ(2573) region 2dim E,Mbc fit incosbins to filter out background Signal events 3body signal MC-> acceptance cos helicity angle : angle between the K+ direction in the D0K+ rest frame and the D0K+ direction in the rest frame of (4S) cos
SIGNAL with subtracted bckg ( efficiency corrected) JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 Angular distribution B+ D0D0K+ B0 D-D0K+ For2.65 <M( D0K+ ) < 2.80 GeV X(2730) region :helicity angle Very asymmetric! Interference effect? Signal events Signal events cos cos 3body signal MC 3body signal MC cos cos
JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 Inclusive analysis: D(*)K production from continuum e+e- D(*)K X Selection criteria: • accepted tracks with:abs(IP_dz)< 5cmabs(IP_dr)< 0.4cm K± :P(K/) > 0.4± : P(/K) > 0.1el. veto:el_id < 0.95 K0S :abs( M(+ -) - MKs ) < 15MeVonly good_K0s 0: E > 50 MeVabs( M( ) -M0 ) < 15MeV • D(*) reconstruction D0K abs(M(D)-M(DPDG) ) < 20MeV vertex fit (cl > 0.) D*± D0±abs(M(D*±)-M(D)-mPDG) < 2.5MeV D*0 D00abs(M(D*0)-M(D)-mPDG) < 5.0MeV vertex fit (cl > 0.)applied • p*(D(*) K) > 2.5 GeVin (4S) system ( for ~140 fb-1 on resonance)
JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 mass spectrum of D0K+ from e+e- D0K+ X DS1(2536) D0(0)K+ DSJ(2573) p*(DK) > 2.5 GeV Very good place for precise measurement of DSJ(2573) DS1(2536) properties N/10MeV p*(DK) > 4.0 GeV K± :P(K/) > 0.6± : P(/K) > 0.6 N/10MeV ? STH @ ~2650 abs(M(D)-M(DPDG) ) < 10MeV coshel> -0.7 (to remove bckg: slow K randomly associated with D) No supporting evidence for X(2730) from continuum,at this stage M(DK) - M(D)
JOLANTA BRODZICKA B D(*) D(*) K DCMarch 03, 2004 mass spectrum of D*0K+ , D*+ K0s from e+e- D*K X DS1(2536) N/10MeV p*(D*K) > 3.5 GeV K± :P(K/) > 0.6± : P(/K) > 0.6 coshel> -0.7 M(D*K) N/10MeV (smaller binning necessary ) M(D*K) - M(D*)