Recent results on CKM/CPV from Belle

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1 Recent results on CKM/CPV from Belle Alexander Leopold for the Belle Collaboration Insitute of High Energy Physics Austrian Academy of Sciences HEPMAD 15, September 21 st 2015 A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 1 / 35

2 Outline reminder of CKM Matrix and Unitarity Triangle parameters accessible from B-Meson decays analyses and results summary and outlook A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 2 / 35

3 The historical path to the CKM Mechanism different decay strengths in strangeness conserving and non-conserving decays mixing of quarks by Cabibbo (1963) to save weak universality ( ) ( cos Θ u, c c sin Θ c sin Θ c cos Θ c ) ( ) d s A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 3 / 35

4 The historical path to the CKM Mechanism different decay strengths in strangeness conserving and non-conserving decays mixing of quarks by Cabibbo (1963) to save weak universality suppression of flavour changing neutral currents introduction of c quark, GIM mechanism (1970), c quark discovered 1974 ( ) ( cos Θ u, c c sin Θ c sin Θ c cos Θ c ) ( ) d s A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 3 / 35

5 The historical path to the CKM Mechanism CP violation observed in Kaon decays ( u, c, ) t V ud V us V ub V cd V cs V cb V td V ts V tb d s b A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 4 / 35

6 The historical path to the CKM Mechanism CP violation observed in Kaon decays add third quark family, naturally includes CPV by irreducible phase in CKM matrix (1973) ( u, c, ) t V ud V us V ub V cd V cs V cb V td V ts V tb d s b A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 4 / 35

7 The CKM matrix different parametrizations for CKM matrix c 12 c 13 s 12 c 13 s 13 e iδ V CKM = s 12 c 23 c 12 s 23 s 13 e iδ c 12 c 23 s 12 s 23 s 13 e iδ s 23 c 13 s 12 s 23 c 12 c 23 s 13 e iδ c 12 s 23 s 12 c 23 s 13 e iδ c 23 c 13 1 λ2 2 λ Aλ 3 (ρ iη) V CKM = λ 1 λ2 2 Aλ 2 Aλ 3 (1 ρ iη) Aλ O(λ 4 ) Wolfenstein parametrization, expansion in λ = V us ρ + i η = VudV ub V cdv cb transitions of up-type quarks to down-type quarks and vice versa A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 5 / 35

8 Unitarity Triangle V CKM is unitary by construction V V = 1 and V V = 1 the unitarity triangle is one of 6 independent relations V ud V ub + V cdv cb + V tdv tb = 0 controls semileptonic and non-leptonic B d transitions represented as triangle in complex plane V ij need to be measured, measurements need to be consistent with each other to proof CKM mechanism A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 6 / 35

9 A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 7 / 35

10 Luminosity A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 8 / 35

11 Observables from B decays η b u B πlν B X u lν b uūd B 0 ππ B 0 ρρ B 0 ρπ b c B Dlν B X c lν V ud V ub V cd V cb φ 2 V td V tb V cd V cb b c cs B J/ΨK 0 s b cūs B ± DK ± φ 3 φ1 (1,0) ρ A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 9 / 35

12 Measurement of time dependent CP violation time dependent indirect CP violation from interference of decay without mixing and decay with mixing b B 0 d t c J/Ψ b d c d K0 s s W + B0 W W B 0 s c Ks d 0 b W J/Ψ d c t A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 10 / 35

13 Measurement of time dependent CP violation produced B B pair is in coherent state flavor tagging reconstruct vertices measure t A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 11 / 35

14 Measurement of time dependent CP violation indirect CPV direct CPV time dependent asymmetry A( t) = S sin( m d t) C cos( m d t) = Γ B0 ( t) Γ B 0 ( t) Γ B0 ( t)+γ B 0 ( t) measure Γ( t) distribution for tagged B and B A( t) measure t extract S & C from fit to A( t) A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 12 / 35

15 φ 1 from B 0 J/ΨK 0 S φ 1 = arg ) ( V cdvcb V td Vtb φ 1 measured from experimentally and theoretically clean golden mode B 0 J/ΨK 0 S S = sin (2φ 1 ) and C = 0 [Belle (PRL 108 (2012) )] A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 13 / 35

16 φ 1 at B factories BaBar PRD 79 (2009) BaBar χ c0 K S PRD 80 (2009) Belle PRL 108 (2012) LHCb arxiv: Average HFAG b ccs C CP H F A G Moriond 2015 PRELIMINARY ± ± ± ± ± ± ± ± ± measurement is compatible with C = 0 Average HFAG BaBar PRD 79 (2009) Belle PRL 108 (2012) Average HFAG BaBar PRD 79 (2009) Belle PRL 108 (2012) Average HFAG BaBar PRD 79 (2009) Belle PRL 108 (2012) Average HFAG BaBar PRD 79 (2009) Belle PRL 108 (2012) Average HFAG BaBar PRD 79 (2009) BaBar PRD 79 (2009) sin(2β) sin(2φ 1 ) HFAG HFAG Moriond 2012 HFAG Moriond 2012 HFAG Moriond Moriond 2012 HFAG Moriond 2012 H F A G Moriond 2012 PRELIMINARY ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± S = ± A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 14 / 35

17 φ 1 world average BaBar PRD 79 (2009) BaBar χ c0 K S PRD 80 (2009) BaBar J/ψ (hadronic) K S PRD 69 (2004) Belle PRL 108 (2012) ALEPH PLB 492, 259 (2000) OPAL EPJ C5, 379 (1998) CDF PRD 61, (2000) LHCb arxiv: Belle5S PRL 108 (2012) Average HFAG sin(2β) sin(2φ 1 ) H F A G Moriond 2015 PRELIMINARY 0.69 ± 0.03 ± ± 0.52 ± 0.04 ± ± 0.42 ± ± 0.02 ± ± ± ± 0.04 ± ± 0.58 ± ± φ 1 = (21.9 ± 0.7) A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 15 / 35

18 Measurement of φ 2 φ 2 = arg ) ( V tdvtb V ud Vub access φ 2 via time-dependent CP asymmetry in: B 0 ππ B 0 ρρ B 0 ρπ penguin contribution has to be controlled in analysis ( S = sin 2φ eff 2 ) with φ eff 2 = φ 2 + φ 2 C 0 direct CP violation from interference of tree and penguin A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 16 / 35

19 Results on φ 2 from B 0 ππ: [PRD 88, (2013)] 1.0 CKM f i t t e r EPS 15 ππ/ρρ/ρπ (BABAR) ππ/ρρ/ρπ (Belle) ππ/ρρ/ρπ (WA) CKM fit 0.8 p value φ W Aππ 2 = ( ) φ (deg) 2 φ all 2 = ( ) [CKM fitter] A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 17 / 35

20 Measurement of φ 3 ( φ 3 = arg V udv ub V cd V cb ) interference between B D( f)k and B D( f)k method depends on choice of final state f: common final state Cabibbo-suppressed decays (D K + K or D K 0 s π 0 ) Cabibbo-favoured decays (D K ± π ) Dalitz plot analysis (D K 0 s π + π ) no penguin contributions precision limited by small branching ratios M Gronau and D Wyler, Phys. Lett. B 265, 172 (1991) M Gronau and D London, Phys. Lett. B 253, 483, (1991) D Atwood, I Dunietz and A Soni, Phys. Rev. Lett (1997) A Giri et al, Phys. Rev. Lett. D 68, (2003) A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 18 / 35

21 Dalitz method for measuring φ 3 from multi-body decays (D K 0 s π + π ) Amplitude for B DK: A B (m 2 +, m 2 ) = ĀD + r B e i(δ B+φ 3 ) A D with m 2 ± = m 2 K 0 s π± = s ± model A D model dependent add resonances until Dalitz plot structures are reproduced model independent binned Dalitz plot B 0 D 0 K 0 [Belle, ] N i ± { = h B K±i + rs 2 K i + 2k K i K i (x ± c i ± y ± s i ) } x ± = r b cos(δ B ± φ 3 ), y ± = r b sin(δ B ± φ 3 ) A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 19 / 35

22 Dalitz method for measuring φ 3 from multi-body decays (D K 0 s π + π ) Amplitude for B DK: A B (m 2 +, m 2 ) = ĀD + r B e i(δ B+φ 3 ) A D with m 2 ± = m 2 K 0 s π± = s ± model A D model dependent add resonances until Dalitz plot structures are reproduced model independent binned Dalitz plot B 0 D 0 K 0 [Belle, ] N i ± { = h B K±i + rs 2 K i + 2k K i K i (x ± c i ± y ± s i ) } x ± = r b cos(δ B ± φ 3 ), y ± = r b sin(δ B ± φ 3 ) A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 19 / 35

23 Measurement of φ CKM f i t t e r CKM 14 Belle GLW+ADS Belle GGSZ Belle Combined 1.0 CKM f i t t e r CKM 14 Belle LHCb Full Frequentist treatment on MC basis Combined BaBar p value p value γ γ φ GGSZ 3 = ( ± 3.6(sys) ± 8.9(model)) φ GGSZ 3,MI = ( ± 4.1 ± 4.3) φ Belle 3 = ( ) φ World 3 = ( ) [CKM fitter] A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 20 / 35

24 Measurement of V cb exclusive decays B Dl ν B inclusive decays B X c l ν with any hadronic state X c A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 21 / 35

25 Hadronic tagging neutrino not detected solution: missing information on energy and momentum huge combinatorial background measure four momentum of hadronically decaying B tag determine missing mass of signal side reduce combinatorial background A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 22 / 35

26 Hadronic tagging with neural networks price of hadronic tagging: reduces efficiency by factor of about 1000 hierarchical approach [ ] use the high classification powers of neural networks one neural network for every decay mode of every particle A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 23 / 35

27 V cb from exclusive decays access V cb from differential decay width of B Dlν dγ dω = G2 F m3 D 48π 3 (m B + m D ) 2 ( ω 2 1 ) 3/2 ηew 2 V cb 2 G(ω) 2 ω = v B v D = m2 B +m2 D q2 2m B m D B A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 24 / 35

28 V cb from exclusive decays - hadronic tagging neutrino ν not detected fully reconstruct tag side B meson, infer neutrino exploit conservation of energy and momentum missing mass M 2 miss = 0 A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 25 / 35

29 V cb from exclusive decays measure Γ in different ω-bins determine spectrum Γ ω and extract V cb from fit form factor G(ω) 2 calculated from lattice QCD or Light Cone Sum Rules CLN: V cb η EW = (40.93 ± 1.33) 10 3 BGL: V cb η EW = (42.09 ± 1.07) 10 3 A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 26 / 35

30 V cb from inclusive decays access V cb from inclusive decays B X c lν [ ] ( ( )) Γ = G2 F m5 b V 192π 3 cb c 5(µ) O 5 (µ) + c 6(µ) O 6 (µ) + O 1 m 2 b m 3 b m 4 b uses operator product expansion coefficients c i are calculated perturbatively hadronic matrix elements O i experimentally determined from other observables (OPE expanded moments) measure width Γ and determine V cb A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 27 / 35

31 Results on V cb preliminary B Dlν results (as presented by R. Glattauer at EPS-HEP 2015) exclusive inclusive V cb η EW (BGL) = (42.09 ± 1.07) 10 3 V cb η EW (CLN) = (40.93 ± 1.33) 10 3 A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 28 / 35

32 Measurement of V ub exclusive decays B πlν B u π 0 inclusive decays B X u lν with any hadronic state X u A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 29 / 35

33 V ub from exclusive decays access V ub from differential decay width of B πlν dγ dq 2 = G2 F p3 π 24π 3 V ub 2 f Bπ + (q 2 ) 2 measure spectrum of branching fraction in bins of q 2 extract V ub from fit to data (include data points from LQCD) Belle, [ ] A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 30 / 35

34 V ub from inclusive decays B X u lν summing over all hadronic final states with a u quark uses hadronic tagging identifies signal event from high momentum e or µ has to deal with very high background from B X c lν (x50) obtain V ub from partial branching fraction B ulν V ub 2 = B ulν τ B R predicted partial rate R A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 31 / 35

35 V ub CLEO (E e ) 4.28 ± BELLE sim. ann. (m, q 2 ) X 4.49 ± BELLE (E e ) 4.93 ± BABAR (E e ) 4.54 ± BABAR (E max e, s ) h 4.53 ± BELLE multivariate (p*) 4.49 ± BABAR (m <1.55) X 4.30 ± BABAR (m <1.7) X 4.04 ± 0.22 ± BABAR (m <1.7, q >8) X 4.30 ± BABAR (P + <0.66) 4.15 ± BABAR (p*>1gev) 4.32 ± BABAR (p*>1.3gev) 4.32 ± Average +/- exp + th. - th ± inclusive (BLNP) χ 2 /dof = 9.0/11 (CL = %) Bosch, Lange, Neubert and Paz (BLNP) Phys.Rev.D72:073006,2005 HFAG PDG V [ 10 ] ub exclusive 2 2 Khodjamirian et al. q < 12 GeV 3.41 ± Ball-Zwicky q < 16 GeV 3.58 ± HPQCD q > 16 GeV 3.52 ± FNAL/MILC q > 16 GeV 3.36 ± HFAG PDG V ub [10 ] A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 32 / 35

36 Summary overconstrain apex of triangle many different techniques to measure CKM parameters η excluded area has CL > 0.95 sin 2φ 1 φ 3 φ 2 m d m d & m s ε K φ φ φ 1 φ V ub CKM f i t t e r EPS 15 sol. w/ cos 2φ < 0 1 (excl. at CL > 0.95) ρ measurements consistent with KM mechanism resulted in Nobel Price for Kobayashi and Maskawa in 2008 A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 33 / 35

37 Outlook start of Belle 2 data taking planned for 2018 expected sensitivity of Belle 2: Observable Belle 2006 Belle 2 Belle 2 LHCb LHCb ( 0.5ab 1 ) (5ab 1 ) (50ab 1 ) (2fb 1 ) (10fb 1 ) sin(2φ 1 ) φ 2 (ππ) φ 3 (Dalitz MI) V ub (incl) 6% 5% 3% - - V ub (excl) 15% 12% 5% - - A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 34 / 35

38 Thank you for your attention. A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 35 / 35

39 Backup A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 1 / 4

40 φ 1 systematics A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 2 / 4

41 φ 2 systematics A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 3 / 4

42 φ 3 systematics A. Leopold (HEPHY) Belle HEPMAD 2015/09/21 4 / 4