Measurement of the CKM-angle g at BABAR and Belle J.P.Lees, LAPP-Annecy (IN2P3-CNRS), for the BaBar and Belle collaborations g/f3 with B±→D(*)0K(*)± (GLW, ADS, GGSZ) 2b+g/2f1+f3 with B0 →D(*)+p-/D(*)-p+ and others Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Determining g in B±→D(*)0K(*)± Color suppressed (C) Favored (T) A1 3 A2 3(2+2) e-ig eid Interference between Interference if same D0 and D0 final states: Atot=A1+A2 F G L W m e t h o d : D ; ¹ ! K + ¡ ¼ S s Á A ( u p r . ) , f a v Z [ l i z ] FCS [0.2,0.6] (0.3 for B0→ D0 p0) Theoretically clean (no penguins) 0,360.04 3 parameters rB , g and d C r i t c a l p m e B = ¯ A ( ¡ ! ¹ D K ) ´ 2 + ½ £ F S Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

The GLW Method & observables Clean but statistically limited: Bf(B-→D0K-)  Bf(D0 → cp)  10-6 Asymmetry B-/B+ for CP=+1/-1 Ratio of Bf for CP/non CP A C P § = B ( ¡ ! D K ) + R C P § = B ( + ! D K ) ¡ = § 2 r B s i n ( ± ) ° R C P = 1 + r 2 B § c o s ( ± ) ° 8 fold ambiguity on g ACP ACP- g=60o RCP RCP+ g=60o g=30o rB=0.1 g=30o R C P + ¡ 2 = 1 r B RCP- ACP+ g=90o g=90o Weak sensitivity to rB Strong phase d (radians) Strong phase d (radians) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Measurement techniques For D(*)0K use Cancellation of many systematics Reconstruct B→D0h with D0→Kp [NON CP], D0 → K+K-,p+p- [CP+] and D0 → K0sp0 (K0sw,K0sf) [CP-] Eliminate background from qqbar/ccbar events using Neural Net or Fisher discriminants based on event shape variables Fit of R(K/p) based on kinematic variables (DE) and PID (for each mode / charge) B →D0K B →D0p Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g BaBar GLW results 2 3 £ 1 6 B ¹ D0K D0p 148 CP- PRD 73, 051105(R) (2006) B→D0K 131 CP+ A C P ¡ = : 2 6 § 4 1 + 8 9 R 5 B→D0K* PRD 72 (2005) 071103 B+ CP+ B- CP+ B+ CP- B- CP- 14.8 B CP- 37.6 B CP+ R C P + = : 9 § 1 2 4 ¡ 8 6 5 A 3 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g 70.2 ± 14.7 79.2 ± 15.7 Belle GLW results D0K+ D0K- CP+ CP+ PRD 73, 051106(R) (2006) 275x106 B Bbar pairs 149.5 ± 19.0 CP- evts B→D0K D0K+ D0K- R C P + = 1 : 3 § 6 8 ¡ 7 4 A 5 2 CP- CP- B→D*0K (D*0→ D0p0) R C P + = 1 : 4 § 2 5 6 ¡ 3 A 8 43.9 ± 10.2 32.7 ± 10.0 D*0K D*0K CP+ CP- Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

RCP and ACP World Averages J-P Lees, Measurement of the CKM-angle g D0K D*0K D0K* CP+ CP+ CP- CP- CP+ CP+ CP- CP- CP+ CP+ CP- CP- GLW measurements alone do not constraint g/f3. Information on g and rB from combination with other methods. More statistics will help! Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Combine dominant b→c transition with DCS D0 decay g/f3 with the ADS method dB dD A1 A2 Combine dominant b→c transition with DCS D0 decay A (B-→[K+p-]DK-)  rBei(dB-g)+rDe-idD Small BF(~10-7), but A2 = O(A1): expect large CPV Observables: Measure [K+p-]K- and [K-p+]K- rates Large sensitivity to rB input: Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

B-→D(*)0[K+p-]K(*)- ADS 2 3 £ 1 6 B ¹ PRD 72 (2005) 032004 Suppressed channel not visible in D(*)0K R ¤ K ¼ ; D ° < : 4 5 R ¤ K ¼ ; D < : 2 3 R K ¼ < : 2 9 B→ D*0K(D*0→D0g) B→ D*0K (D*0 → D0p0) B→ D0K B→ D0K* R ¤ K ¼ ; D + ° 2 ¡ r = B Bondar & Gershon PRD70,091503(2004) 4.2  2.8 ev  r*B2<(0.16)2 @ 90% C.L. Constraints on rB from D*0K R S K ¼ = : 4 6 § 3 1 8 PRD 72 (2005) 071104 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

BaBar constraints on rB J-P Lees, Measurement of the CKM-angle g D0K*+ R K ¼ = r 2 B + D c o s ( ° ) ± g [0,p] & (dD+dB)[0,2p] D0 K GLW ADS combination 1-CL 1s 48o<g<73o 2s R K ¼ < : 2 9 3s rSB rSB= For maximum mixing (g/φ3=0, δ=180°): rB<0.23 @ 90% C.L. DK*, GLW+ADS combined Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

B-→D0[Kp]K- ADS(Belle) J-P Lees, Measurement of the CKM-angle g hep-ex/0508048 386  106 B Bbar pairs Despite larger statistics, suppressed channel not visible either: D0K R K ¼ < 1 3 : 9 £ ¡ maximum mixing (φ3=0, δ=180°): rB<0.18 @ 90% C.L. Here too, more statistics will help! Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Dalitz Analysis of B- D(*)0[KSp+p-]K- A.Giri, Y.Grossman,A.Soffer & J.Zupan, Phys.Rev. D68, 054018 (2003) A1 = A(B-→D0K-) AD(m2Ksp-,m2Ksp+ ) A2 = rB e-igeid |A(B-→D0K-)| AD(m2Ksp+ ,m2Ksp-) - rB if D*0→D0g Get rB, g, d from simultaneous fit of the Ksp+p- dalitz plot density of B- and B+ data Sensitivity to g is here! ds(m-,m+)  |AD(m-,m+)|2 + rB2 |AD(m+,m-)|2 B-→B+  m-  m+ and –g → +g + 2 rB Re [ AD(m-,m+)AD*(m+,m-)ei (-g+d) ] Some model uncertainty in the g/f3 measurement Need precise knowledge of AD(m-2,m+2) 2 fold ambiguity on g: ( g, d ) →( g+p , d+p) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Sensitivity to g Sensitivity to g varies across the dalitz plot: w1/(d2L/dg2) g=75,d=180,rB=0.125 Interference of B-→ D0K-, D0 →K0Sr0 with B-→D0K-,D0→K0Sr0  GLW like DCS K*(1430) r(770) Interference of B-→D0K-, D0 →K*+p- (suppressed) with B-→D0K,D0→K*+p-  ADS like DCS K*(892) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

D0 Dalitz model for A(m-2,m+2) extract A(m-2,m+2) from high purity tagged D*+→D0p+ , D0→K0p+p- sample use isobar model (  coherent sum of Breit-Wigner (BW) amplitudes) CA K*(892) r(770) DCS K*(892) Â 2 = d : o f 1 7 BaBar: 16 resonances (3 WS DCS) + 1 NR component Belle: 15 resonances (4WS DCS) + 1 NR component Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Cartesian coordinates From previous studies, parameters (rB, g, d) badly behave statistically No sensitivity to g for rB<0.10 (+underestimated errors on g and d) fit biases on rB for rB ~0.1 [physical bound rB>0 + low statistics] Fit cartesian coordinates (x, y) instead (4 parameters) x  = Re (rBei(dg)) y = Im (rBei(dg)) Gaussian Errors on x,y (no unphysical zone) (x+,y+), (x-,y-) uncorrelated Unbiased results  rB  Easier to combine different results Note: GLW results also sensitive to x x § = R C P + ( 1 ¨ A ) ¡ 4 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

B-→D(*)0K(*)- Data sample (BaBar) PRL 95 (2005) 121802 & hep-ex/0507101 227  106 B Bbar D0K D*0K (D0p0) 9011 D0K D0K m+2 (GeV2/c4) 28220 m-2 (GeV2/c4) B- B+ m-2 (GeV2/c4) m+2 (GeV2/c4) D*0K (D0g) 448 D0K* 428  Simultaneous fit of the D0 Dalitz plots for B+ and B- data using the D0 isobar decay model previously described Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Belle data sample 357 fb-1 ~ 392  106 B Bbar New! Preliminary! B→ D*0K B→ D0K* B→ D0K 331±17 events 81±8 events 54±8 events B- B+ B- B+ B- B+ Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Dalitz (x,y) fit results J-P Lees, Measurement of the CKM-angle g Belle: New! Preliminary! Dalitz (x,y) fit results 357 fb-1 ~ 392  106 B Bbar D0K* D0K D*0K 2g BaBar: PRL 95 (2005) 121802 & hep-ex/0507101 227  106 B Bbar B+ D0K* D0K B- D*0K B+ B+ B- d = 2 rB|sin g|  size of direct CPV B- 2.5s Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

B- B+ Summary of x and y  measurements x- y- y+ x+ x=rB cos(dB  g) HFAG uncorrelated averages (Dalitz Only) B- B+ x- y- y+ x+ x=rB cos(dB  g) y=rB sin(dB  g) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Constraints on rB and g From the 12 measured parameters (x, y, x*, y*, xS, yS) build 7d confidence levels on (g, rB, d, rB*,d*,rsB, ds) through a frequentist [Neymann] approach:  2d projections contours (1s, 2s) on rB, g g = 67o  28o (stat)  13o (syst)  11o (Dalitz model) rb = 0.12±0.08±0.03±0.04 DK rb* = 0.17±0.10±0.03±0.03 D*K rs < 0.19 @ 90% CL DK* pdf shapes (mES, …) Dalitz structure of background efficiency in the dalitz plot Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Constraints on rB and g (Belle) New! Preliminary! BDK BDK* BD*K φ3=66-20 °(stat) φ3=86-93°(stat) φ3=11-57°(stat) +19 +37 +23 Combined for 3 modes: φ3=53°+15 3° (syst)9° (model) 8°<φ3<111° (2σ interval) rDK =0.159+0.054 0.012(syst)0.049(model) CPV significance: 78% rD*K=0.175+0.108 0.013(syst)0.049(model) rDK*=0.564+0.216 0.041(syst)0.084(model) -18 -0.050 -0.099 -0.155 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g sin(2+) in B0D(*),D Exploit mixing and interference between b  c (favored) b  u (Doubly-Cabibbo suppressed) Vcb V*ud  1  l2 l 3 (2+2) e-ig Vcd e-ib V*ub u,c,t u,c,t e-ib A1 Vcb V*ud A2  e-i(2b)Vcd V*ub = r A1 e-i(2b+g) ei(d) Favored decay has “large” branching fraction (~0.3-0.8%) = strong phase difference But…. r estimated from Bf(B0→ Ds+ p-) + SU(3) flavor symmetry small CP asymmetry r = ¯ A ( B ! D ¤ ) + h ¡ ¹  l2 (0.02) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Experimental technique (4s) bg = 0.56 Tag B sz ~ 160 mm Reco B sz ~ 80 mm Dz K D- K+ + - e- e+ B0  Time dependent analysis Partial or Full reconstruction Unmixed D- p+ r = 0.02  = 0 sin(2+) = 1 w=0 Mixed D- p+ r = 0 Unmixed D+ p- D*-p+ mixed Mixed D+ p- Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

CP violation on tag side - Potential competing CP violating effects from b → u transitions on the tag side if a Kaon is used to tag the B Slept 2 r (sin(2b+g  d) lepton Tags Kaon Tags SK 2 r (sin(2b+g  d) + 2 r’(sin(2b+g  d’) Rewrite as S = (a  c) + b a = 2r sin(2b+g) cos (d) c= cos(2b+g) [2r sin(d)+2r’sin(d’)] b = 2r’ sin(2b+g) cos (d’) free of tag-side CPV Lepton tags free of tag-side CPV BaBar: fit CP observables a and clepton (free of tag-side CPV). Belle: Fit S+ and S- (partial reco: only lepton tags) Full reco: use all tags but measure tag side CPV parameters S+’ and S-’ from a sample of D*ln evts [only tag side cpv) a = (S++S-)/2 c = (S+-S-)/2 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

B0D* partially reconstructed (BaBar) 232  106 B Bbar Increase the statistics by reconstructing only the two pions - 18710 D* events tagged with a lepton (purity = 54%) - 70580 D* events tagged with a kaon (purity 31%) Most precise measurement to date CP asymmetry PRD 71, 112003[2005] Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

sin(2+) from B0D(*),D Results from B0→ D(*)p, Dr full reco : Combine partial and fully reco results for the a and clep parameters and use the r parameters from SU(3) symmetry hep-ex/0602049 r(D) = 0.019 ± 0.004 r(D*) = 0.015 ± 0.006 r(D) = 0.003 ± 0.006 D+p- 15038 evts, purity 87% D*p 14002 evts purity 87% 30% theoretical error on rf D*r 8736 evts purity 82% |sin(2+)| > 0.64 @ 68 % C.L. |sin(2+)| > 0.42 @ 90 % C.L. aDp = -0.010  0.023  0.007 aD*p = -0.040  0.023  0.010 aDr = -0.024  0.031  0.009 90% CL 68% CL Frequentist confidence level cDp = -0.033  0.042  0.012 cD*p = +0.049  0.042  0.015 cDr = -0.098  0.055  0.018 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g New! Preliminary! New! hep-ex/0604013 sin(2φ1+φ3) (Belle) 357 fb-1 ~ 392  106 B Bbar - full reconstruction D*π partial rec (only lepton tags) D*π full rec Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g New! hep-ex/0604013 submitted to PRD sin(2φ1+φ3) 1s 2s 3s S- S- S +(D*π)=0.049±0.020±0.011 S –(D*π)=0.031±0.019±0.011 S +(Dπ)=0.031±0.030±0.012 S –(Dπ)=0.068±0.029±0.012 Full-rec + partial-rec Full-rec CPV significance (S++S-): 2.5σ [D*p], 2.2s [Dp] S+ S+ |sin(2φ1+φ3)|>0.46 (0.13) Using RD*p = 0.0210.007  0.006 |sin(2φ1+φ3)|>0.48 (0.07) at 68% (95%) CL 1s 2s 3s Using RDp = 0.0210.004  0.006 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g HFAG averages a and c parameters a = 2r sin(2b+g) cos (d) clept = 2 r cos(2b+g) sin(d) a = (-1)l(S++S-)/2 [belle] More statistics will help! Individual measurements of a close to the 3s statistical significance! c small  dDp and dD*p small? Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Bf(B0 → Ds(*) p) New! hep-ex/0604012, submitted to PRL 230  106 B Bbar B ( ! D ¤ + s ¼ ¡ ) = 2 : 8 § 6 5 £ 1 3 Ds→ fp, K0SK+, K*0K+ N(Ds+p-)=48 N(Ds*+p-) = 42 Measure also B ( ! D + s K ¡ ) = 2 : 5 § 4 £ 1 B ( ! D ¤ + s K ¡ ) = 2 : § 5 4 £ 1 W-exchange diagrams are small SU(3) r(Dp) = (1.3  0.2  0.1 ) 10-2 r(D*p) = (1.9  0.2  0.2 ) 10-2 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g B0→D(s)(*)+a-0(2) Theory papers: Phys.Lett.B 517,125 (2001) JHEP 0106:067 (2001 PRD 67, 014011 (2003) Other (crazy?) ideas b  c amplitude ~ suppressed in B0→D(*)+a-0(2) Potentially large CP-asymmetry b  c a0(2) l b  u fa0(2)<<fp a0(2) Test B of the suppressed decay using the SU(3) related mode: Ds(*) B0→Ds(*)+a-0(2) a0(2) fD= decay constant Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g 232  106 B Bbar hep-ex/0512031 (2005) Submitted to PRD B0->Ds(*)+a-0(2) Theory prediction: No evidence for signal Upper limits for BF are smaller than theoretical expectation. New Mode not usable to measure sin (2β+γ) B ( ! D + s a ¡ ) < 1 : 5 £ 2 9 3 6 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

sin(2b+g) with B0 /B0 → D(*)0K(*)0 3 (2+2) e-ig l2 Vub and Vcb mediated amplitudes both color suppressed: Expect large asymmetries But smaller branching fractions than for Dp l ~ 1 A1VcbVus A2= rB A1e-igeid Critical parameter: = ¯ V u b ¤ c s ' : 4 ? Measure the different D(*)0K(*)0 Bf Measure rB in self-tagging final state D0K*0 (assuming that rB for DK*  same as rB for DK0) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

D(*)0K(*)0 No signal in the suppressed mode 7712 D0K*0 D0K*0 D0K0 10414 D*0K0 175 232  106 B Bbar To be submitted to PRD No signal in the suppressed mode rB value smaller than theo. expectation Not useful to measure  value yet! B ( ! D K ) = 5 : 3 § 7 £ 1 ¡ ¤ 6 2 ¹ 4 < Equivalent Belle result on 86M BB PRL 90, 141802 (2003) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Summary Many new or final results since last summer GLW: BaBar (Belle) with 232 (275) million B’s Clean but statistically limited. Best precision is in the D0K channel ADS: 232 (386) million B’s rB is small: rB(D0K)<0.18, rB2(D*0K)<0.162 @ 90% CL Hints of larger rB in the DK* channel need confirmation Dalitz: 232 (386) million B’s Most powerful method, sensitive to both rB and g New Belle result. Good Belle vs BaBar agreement on D(*)0K x/y contours. Observation of direct CPV @3s is within reach…. 2b+g with D(*)p/r: 232 (386) million B’s Difficult and challenging analysis Observation of CPV @ 3s is within reach…. Good perspectives with higher statistics since the theoretical uncertainties are very low: stay tuned Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Backup Slides Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Numeric results of the daliz (x,y) fit babar belle x–= 0.025-0.080 y–= 0.170-0.117 x+= –0.135-0.070 y+= –0.085-0.086 +0.072 +0.093 +0.069 +0.090 x-= –0.128-0.146 y-= –0.339-0.158 x+= 0.032-0.116 y+= 0.008-0.136 +0.167 +0.172 +0.120 +0.137 PRL 95 (2005) 121802 Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g Time dependent distribution for B0 D + - Mistag probability Resolution function + - 1 d) oscillation frequency Warning: definition of C and S slightly different between Belle & BaBar Ideal case D*-p+ unmixed D*-p+ mixed D+-p- mixed CP violation Only cosine: r = 0 r = 0.02  = 0 sin(2+) = 1 w=0 Dt (ps) Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

B0→ D(*)p, Dr full reco (BaBar) Lepton tags, D* final state D*-p+, mixed D*+p-, mixed Dt (ps) background Babar full reco hep-ex/0602049 232  106 B Bbar D+p- 15038 evts purity 87% D*p 14002 evts purity 87% aDp = -0.010  0.023  0.007 aD*p = -0.040  0.023  0.010 aDr = -0.024  0.031  0.009 cDp = -0.033  0.042  0.012 cD*p = +0.049  0.042  0.015 cDr = -0.098  0.055  0.018 D*p 8736 evt purity 82% Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

J-P Lees, Measurement of the CKM-angle g HFAG averages : D*+ p- More statistics will help! Individual measurements of a close to the 3s statistical significance! Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g

Determination of rf We currently use SU(3) to estimate rf: f = Dp, D*p, Dr 2 observables for 3 unknowns  need to know r to determine 2+ We currently use SU(3) to estimate rf: SU(3) Note: New Babar measurement of Bf(B→Ds(*)p) : see next We add theoretical uncertainty on rf  30-100% (under discussion among theorists) SU(3) may not hold Exchange diagrams neglected Vancouver, April 9, 2006 J-P Lees, Measurement of the CKM-angle g