1. Exclusive Semileptonic b  u Decays at CLEO Sheldon Stone Syracuse University

2. CKM Workshop, Dec. 12-16, 20062 Introduction Improved measurements of B o   - + &  - + branching ratios and q 2 dependences Measurement of B +   + & evidence for B +   ’ + Analysis Uses Neutrino Reconstruction Extension of CLEO II/II.5 Analysis (PRD 68, 072003) by adding CLEO III data, 60% more data, total of ~14 fb -1

3. CKM Workshop, Dec. 12-16, 20063 Formalism in Pseudoscalar Decay q 2 =(p B  -p P  ) 2, k P is the P momentum in the B rest frame

4. CKM Workshop, Dec. 12-16, 20064 Formalism in Vector Decay  WL is the  between the + direction in the W rest frame & the W direction in the B rest frame q 2 =(p B  -p V  ) 2, k V is the V momentum in the B rest frame

5. CKM Workshop, Dec. 12-16, 20065 p Resolution p GeV/c Neutrino Reconstruction Estimate 4-vector using p miss  p CM -p visible & E miss  E CM -E visible Require in general net charge of 0, (in 0 - modes also use ±1) Require MM 2 ~0 (MM 2 /2E miss <0.5 GeV) Require Spherical events Identify e + or  + with p >1 GeV/c (reject events with >1 lepton) Form  E=E had +E -E -E beam & M h 2 =E beam 2 -(p had +p +p ) 2  ~0.1 GeV/c

6. CKM Workshop, Dec. 12-16, 20066 Measurement Technique Vector state sensitive to cos  WL Binning B  in q 2 & cos  WL bins drastically reduces model dependence of branching ratio determination B  in q 2 bins B  in all phase space B  ’ in all phase space Ratio Cos 0 q 2 GeV 2 Ball04, Mel, UKQCD, ISGW2 B 

7. CKM Workshop, Dec. 12-16, 20067 Expectations from Simulation Use binned log likelihood method simultaneously in all modes and bins Use isospin constraints & efficiency matrix Signal peaks here Backgrounds peak here

8. CKM Workshop, Dec. 12-16, 20068 Fit Components Backgrounds Signals B  X u other Continuum (absolutely normalized) B  Signal  ±  0  XFeed ,  0 XFeed Data B  X c Events/7.5MeV/c 2 M hlv GeV/c 2 Fake Lepton (absolutely normalized, very small) ,  XFeed (very small)

9. CKM Workshop, Dec. 12-16, 20069 Results from Fit (Summed) M hlv GeV/c 2 Events/7.5MeV/c 2 Events/100MeV/c 2  GeV  +  o  +  o  o   M h Distribution -0.15<  <0.25 GeV  Distribution 5.265< M h < 5.28 GeV

10. CKM Workshop, Dec. 12-16, 200610 Systematic Errors Largest Source Of Systematic Uncertainty

11. CKM Workshop, Dec. 12-16, 200611 B  10 -4 /GeV 2 q 2 GeV 2 HPQCD 04 Prediction Ball 04 Prediction cos  wl <0 cos  wl >0 B  10 -4 /GeV 2 Results B (B  )= (1.37  0.15  0.12  0.01)  10 -4 B (B  )= (2.93  0.37  0.39  0.04)  10 -4 B (B +  + ) = (0.44  0.23  0.11  0.00)x10 -4, <1.01  10 -4 @ 90% cl B (B +  + ) = (2.66  0.80  0.57  0.04)x10 -4, 3  effect  (B +  + )/  (B +  + )>2.5 @90% cl Theory without color singlet has B (B +  + ) =0.4x10 -4, B (B +  + ) =0.2x10 -4, inconsistent with data

12. CKM Workshop, Dec. 12-16, 200612 #BB  10 6 B (B  )  10 4 CLEO Oct 2006 15.4 1.37  0.15 stat  0.12 sys BABAR Jul 2006 227.0 1.44  0.08 stat  0.10 sys BELLE Jun 2006 275.0 1.38  0.19 stat  0.14 sys HFAG ichep06 Avg 1.37  0.06 stat  0.06 sys B (B  ) B  Comparisons Competitive with B factories due to higher efficiencies at symmetric machine

13. CKM Workshop, Dec. 12-16, 200613 B  Comparisons #N  10 6 B (B  )  10 -4 CLEO Oct 2006 15.4 2.93  0.37 stat  0.39 sys BABAR Sep 2005 83.0 2.14  0.21 stat  0.56 sys BELLE Jun 2006 275.0 2.17  0.54 stat  0.32 sys B (B  )

14. CKM Workshop, Dec. 12-16, 200614 Measurement of |V ub | We use our measurement for B  for q 2 > 16 GeV 2 And recent results from unquenched lattice calculation: HPQCD collaboration (Gulez, et al, PRD 73, 074502, 2006). CLEO (2006): BABAR (2006): BELLE (2006): Note that the theoretical error dominates

15. CKM Workshop, Dec. 12-16, 200615 Conclusions Using reconstruction CLEO measured Branching ratios for B → ( , ,  ’) & an upper limit for B →  B (B  )= (1.37  0.15  0.12  0.01)  10 -4 B ( B  )= (2.93  0.37  0.39  0.04)  10 -4 B (B   ’ )= (2.66  0.80  0.57  0.04)  10 -4 “3  evidence for” B (B  ) < 1.01  10 -4 @ 90% C.L. Extracted |V ub | using  q 2 >16 GeV 2 and HPQCD prediction:

16. CKM Workshop, Dec. 12-16, 200616 A Tribute to Bernie Gittelman 1932-Nov. 25, 2006 A hero of flavor physics Pioneered e- storage rings at SLAC First to measure B semileptonic decays Led CLEO II project