RECENT RESULTS ON HADRONIC B DECAYS FROM BELLE

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1 RECENT RESULTS ON HADRONIC B DECAYS FROM BELLE Marko Pet!č on behalf of the Belle Collaboration Rencontres u Vietnam, Winows on the Universe August 14 th 13 1 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 1/19

2 Outline Angular analysis of B φk ecays an search for CP violation submitte to PRD arxiv: [hep-ex] Evience for the ecay B K + K π V. Gaur, et al. (Belle Collaboration), PRD 87, 9111(R) (13) Measurement of φ in B π + π submitte to PRD arxiv: [hep-ex] B ρ ρ arxiv: [hep-ex] / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle /19

3 Belle Experiment Operating at KEKB collier (1999-1). Operate at KEKB accelerator in TOF Counter Aerogel Cherenkov cnt. Asymmetric beam energy:. GeV e Tsukuba, Japan (1999 1) CsI + KEKB took ata mostly on Υ(4S) SC solenoi Booste B meson pair prouce in 8 GeV e e GeV. GeV e Central Drift Chamber Υ(4S) ecays almost entirely to BB Collecte about 77M BB pairs. (77 ± 11) 16 BB pairs recore µ/k etector SVD L Very clean environment for physics stuies All analyses presente in this talk are base on the full Belle ata sample Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 3/ 19 3/19

4 B φk motivation B b u, c, t W + s s s φ K Procees via the b s penguin transition in the SM Sensitive to possible new particle contributions in the loop A baffling pattern in the longituinal polarisations: B φk (89) f L =.45 ±.5 ±. Belle PRL 94, 184 (5) f L =.494 ±.34 ±.13 BABAR PRD 78, 98 (8) B φk (143) f L = ±.37 BABAR PRD 78, 98 (8) QCD factorisation expecte f L 1 Negligible irect CP violation expecte in the SM 4 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 4/19

5 B φk analysis approach B b Partial wave analysis of B φk with K K + π being scalar (Kπ) S wave, J = vector K (89) P wave, J = 1 tensor K (143) D wave, J = Analysis restricte to K + π invariant mass < 1.55 GeV/c W + LASS moel for S wave component (inclues K (143) ) ū, c, t relativistic spin-epenent s Fig.. Breit-Wigner for P an D wave Angular istributions g in the helicity base Simultaneous fit to B an B K in total 6 physics parameters measure in the B φk system FIG. 1: Penguin iagram of the ecay B! K. es. Overall, 6 parameters relate to branching fracs, polarization, interference e ects an CP violation measure. he measurement of polarization in flavor specific! K ecays can be use further to istinguish een CP-even an CP-o fractions in the ecay s s three helicity angles 1,, an, which are efine in the rest frame of the parent particles as illustrate in Marko Petrič (JSI) Rencontres u Vietnam Recent results FIG. : ondefinition haronic Bof ecays the three fromhelicity Belle angles given in the rest 5/ / 19

6 B φk physics parameters φ(kπ) φk (89) φk (143) Parameter Definition J = J = 1 J = B J 1 (Γ J + Γ J )/Γ total B B 1 B f LJ 1 ( A J / A Jλ + A J / A Jλ ) f L1 f L f J 1 ( A J / A Jλ + A J / A Jλ ) f 1 f φ J 1 (arg(a J /A J ) + arg(a J /A J )) φ 1 φ φ J 1 (arg(a J /A J ) + arg(a J /A J ) π) φ 1 φ δ J 1 /A J ) + arg(a /A J )) δ 1 δ A CPJ (Γ J Γ J )/(Γ J + Γ J ) A CP A CP1 A CP A CPJ A CPJ A J / A Jλ A J / A Jλ A J / A Jλ + A J / A A Jλ CP1 A CP A J / A Jλ A J / A Jλ A J / A Jλ + A J / A A Jλ CP1 A CP φ J 1 (arg(a J /A J ) arg(a J /A J )) φ 1 φ φ J 1 J /A J ) arg(a J /A J ) π) φ 1 φ δ J 1 /A J ) arg(a /A J )) δ 1 δ Overview an efinition of the 6 physics parameters φ = 1 arg(a /A ) only accessible in B /B φk S π 6 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 6/19

7 B φk selection an fit Reconstructing B φk with φ K + K, K K + π Cut base selection with neural network (NeuroBayes) base continuum e + e qq backgroun suppression 9D fit to B an B using the observables M bc beam-constraine mass E energy ifference M KK K + K invariant mass C NB continuum suppression network output M Kπ K + π invariant mass φ, cos θ 1, cos θ the three helicity angles Q charge of primary kaon from B With three components inclue in the fit signal peaking backgroun from B f (98)K (89) continuum backgroun 7 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 7/19 S/B separation PWA CP

8 B φk fit results (Preliminary) Total PDF continuum B f (98)K (89) Signal enhance M (a), E (b), M 1 B φk (c) an C () istribution FIG. 4: Projections onto the observable bc (a) Mbc, (b) E, (c) MKK, an () CNB for BNB! (K + ) an B! (K + ) KK combine. The ata istributions are shown by black markers with error bars whereas the overall fit function, combinatorial backgroun, signal an peaking backgroun are shown with soli black, otte black, ashe re an ash-otte blue curves, respectively. For each projection the ata points an fit projections are shown after a signal enhancing selection (see text) on the corresponing other three observables, e. g., in (a) a requirement on (b),(c) an () was applie. Signal enhance MK π (a), cos θ1 (b), cos θ (c) an φ () istributions Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 8/ 19 8/19

9 B φk results (Preliminary) φ(kπ) φk (89) φk (143) Parameter J = J = 1 J = B J (1 6 ) 4.3 ±.4 ± ±.5 ± ± 1. f LJ.499 ±.3 ± ±.1 f J.38 ±.6 ± ±.9 φ J (ra).3 ±.1 ± ±.88 ± 1.3 φ J (ra).37 ±.1 ± ±.13 δ J (ra).91 ±.1 ± ±.11 ±.19 A CPJ.93 ±.94 ±.17.7 ±.48 ± ±.33 A CPJ.3 ±.61 ± ±.8 A CPJ.14 ±.11 ± ±.9 φ J (ra). ±.1 ±.1. ± 1.8 ± 1.1 φ J (ra).5 ±.1 ±..19 ±.4 ±.11 δ J (ra).8 ±.1 ±.1.6 ±.11 ±. B an polarisation parameters consistent with existing results Parameters relate to irect CP violation consistent with zero 9 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 9/19

10 B K + K π motivation B b W + u s s u K K + π B b W + u s s u K /K K + /K + Suppresse in the SM < CLEO PRL 89, 5181 () Contribution from colour- an Cabibbo-suppresse b u tree (LEFT) an internal W exchange (RIGHT) transitions No information on potential resonance moes available BABAR PRL 99, 181 (7) an LHCb LHCb-CONF-1-8 observe a structure in the K + K invariant mass aroun 1.5 GeV/c in B + K + K π + 1 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 1/19

11 B B! K + K + K π - Evience for the ecay evience for the ecay Events / ( 1 MeV ) B! K + K Total PDF Total backgroun Continuum an B B Continuum E (GeV) Events / / CNB Cut base selection with neural network (NeuroBayes) base continuum e + e! q q (q {u,, s, c}) backgroun suppression continuum D fit of e events + e in the qq ±3backgroun region of beam-constraint suppression B mass M bc Fit is using energy ifference E an network output CNB Cut base selection with neural network (NeuroBayes) base D fit of events in the ±3σ region of beam-constraine B mass N sig = 99 ± 83 B(B! K + K )=(.17 ±.6 ±.4) Fit is using energy ifference E an network output C NB Michael Prim EPS HEP 13 - Haronic B Decays at Belle /13 V. Gaur et al. [Belle], PRD 87, 9111 (13) 3.5σ N sig = 99±83 B (B K + K π ) = (.17±.6±.4) / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 11/19

12 4 ) ) ) B K + K π resonant substructure Events / ( 3 MeV/c Events / ( 3 MeV/c B B m + - K K K + K m K (GeV/c ) + π K + K (GeV/c ) BELLE BELLE Events/6.5 MeV/c 3 a) B + K + K 1 4 b) B + K + K m (GeV/c K - π ) m (GeV/c K + K ) - Signal yiel fitte in bins of m K + K an m K + π + + /c Caniates / (.1 GeV B + K + K LHCb Preliminary m (GeV /c 4 ) K + K No efinite statement can be mae about low-mass structure seen in m K + K by BABAR an LHCb Excess of events at aroun m K + π = 1.4 GeV/c Amplitue analysis an more statistics require Belle II 1 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 1/19 +

13 B π + π motivation B b W + u u π + π B b W + Decay ominate by b uu transitions Time evolution: u, c, t u u π + π P( t, q) = e t /τ B 4τ B {1 + q [A CP cos m t + S CP sin m t]} If only tree contribution (LEFT) S CP = sin φ, however penguin contribution (RIGHT) S CP = 1 A CP sin(φ + φ ) 13 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 13/19

14 B π + π analysis an results 9D fit using the observables E, M bc, L + Kπ, L Kπ, R s/b, t, q ) Events / (.5 GeV/c Events / (.15 GeV) Events / (.1) Events / (1.5 ps) Normalise Resiuals M bc (GeV/c ) Normalise Resiuals E (GeV) Normalise Resiuals F BB/qq A CP (B π + π ) = +.33 ±.6 ±.3 S CP (B π + π ) =.64 ±.8 ±.3 q = +1 q = 1 C CP π + π - S CP vs C CP BaBar Belle LHCb Average HFAG Morion 1 PRELIMINARY C CP π + π - S CP vs C CP BaBar Belle LHCb Average HFAG CKM 1 PRELIMINARY B B N B N N B +N OLD -.8. NEW S t (ps) CP S Contours give - (ln L) = χ = 1, corresponing to 6.7% CL for of CP Contours give - (ln L) = χ = 1, corresponing to 6.7% CL for of 14 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 14/19

15 B π + π results etermine φ with a SU() isospin analysis of B ππ into all possible charge states M. Gronau, PRL 65, 3381 (199) A 1 A + 1 A + φ A + = A Nee S, A, B from B π + π, π π an B + π + π φ isospin analysis of only Belle ata B B B π + π B + π + π Exclue at 1σ C.L. 3.8 < φ < B B B π π upating arxiv: [hep-ex] [ ] A. 15 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 15/19

16 B ρ ρ motivation b W + u u ρ B ρ b W + Decay ominate by b uu transitions tree ominate (LEFT) color suppresse (RIGHT) With isospin analysis sensitive to φ ρ ρ final state is not a pure CP eigenstate u, c, t ρ B ρ Longituinal component CP even, transverse CP o + even 16 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 16/19

17 B ρ ρ analysis approach Helicity analysis to extract polarisation information 6D fit using E, M 1 π + π, M π + π, cos θ 1 H, cos θ H, R s/b Dominant backgroun e + e qq, large B 4π ± Events / (.1) (a) (b) (c) Events / (.4) Events / (.4) Normalise Resiuals Events / (.17) Normalise Resiuals ΔE [GeV] qq Normalise Resiuals Events / (.1) Normalise Resiuals m 1 (π + π ) [GeV/c ] Normalise Resiuals Events / (.1) Normalise Resiuals m (π + π ) [GeV/c ] 1 ata total PDF qq+bb (no 4π) 8 BB (no 4π) 4π final states B f ρ 6 B ρ ρ () (e) (f) F S/B cos(θ H1 ) cos(θ H ) 17 / Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 17/

18 B ρ ρ results (Preliminary) I. Aachi et al. [Belle], arxiv: σ B (B ρ ρ ) = (1. ±.3 ±.) 1 6 < at 9% C.L. f L = ±.11 First evience (3.σ) for B(B f ρ ) B(f π + π ) = (.86 ±.7 ±.15) 1 6 φ isospin analysis results orl average B(B ρ + ρ ) L B(B + ρ + ρ ) A +, S + φ = 91. ± 7. BABAR B ρ ρ A, S φ =. ± 5.4 [ ]. 18 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 18/19

19 Summary Angular analysis of B φk, no evience for CP violation f L (φk (143)) = ±.8 f L (φk (89)) =.499 ±.3 ±.18 Evience (3.5σ) for the ecay B K + K π B(B K + K π ) = (.17 ±.6 ±.4) 1 6 Two measurements that provie new constraints on φ most precise measurement of CPV in B π + π A CP (B π + π ) = +.33 ±.6 ±.3 S CP (B π + π ) =.64 ±.8 ±.3 excluing 3.8 < φ < 66.8 (isospin + Belle) measure B ρ ρ at.9σ significance B(B ρ ρ ) = (1. ±.3 ±.) 1 6 evience for B f ρ measurement of φ = 91. ± 7. (iso.+belle+babar+worl) 19 / 19 Marko Petrič (JSI) Rencontres u Vietnam Recent results on haronic B ecays from Belle 19/19