1 Marina Artuso (Syracuse Uni) Jochen Dingfelder (SLAC) Bjorn Lange (MIT) Antonio Limosani (Uni of Tokyo) Tetsuya Onogi (Yukawa Inst. Kyoto) WG2 Thursday 14 December 2006

2 Outline Inclusive Vcb B -> Xs gamma Inclusive Vub Exclusive Vcb Exclusive Vub

3 Inclusive V cb

4 Latest development includes a fit for V cb in the 1S scheme performed by Belle (reported P. Urquijo) 2006 Fit was was also performed to data of other experiments (Babar, Belle, CDF, CLEO, DELPHI - 71 measurements) Compare with fit done similarly in the kinetic scheme by Buchmuller and Flacher circa 2005 Kinetic scheme Fit (H. Flacher) 1S scheme Fit (P.Urquijo)

5 Inclusive V cb The V cb and b-quark mass values from both fits are consistent! Hopes for reducing the error Improved measurements of B->Xs gamma And theory errors … (M. Trott) T. Becher pointed out that in the discussion that calculations from muon decay could help this effort

6 B->X s 

7 Much more data yet to analyse Giving us hope to lower E(cut) to 1.6 GeV

8 B->X s  (P. Gambino)

9 Total error ~7% = ± 3% (interpolation) ± 3% (parametric) ± 3% (higher orders) ± 5% (non-pert) SM prediction now lower than experimental finding Theoretical uncertainty at same level as exp. one Little room, but bounds on new physics remain stringent.

10 B->X s  (T. Becher) Becher & Neubert take the Misiak et al OPE result for Egamma > 1.0 GeV and correct for Egamma > 1.6 GeV using NNLO Multi-scale OPE calculation Theoretical uncertainty at same level as exp. one Little room, but bounds on new physics remain stringent.

11 B->X s  (M. Neubert) There is no local OPE for the total B  X s  decay rate! Nonlocal power corrections (subleading shape functions) starting at order  QCD /m b exist even for the total decay rate Irreducible theory error, of similar magnitude as perturbative uncertainty at NNLO Model estimates suggests effect could lower result by ~5% Measurement of flavor-dependent asymmetry could help to corroborate our model estimates, model (VIA) estimate shows a -2% to -20% effect.

12 Inclusive V ub

13 Inclusive V ub (Experimental development) Recently BABAR measured inclusive Vub using the prescription of Leibovich, Low, and Rothstein (LLR) that extracts Vub with reduced model dependence by combining data of the hadronic mass spectrum from B- >Xulnu decays with that of the photon energy spectrum from B->Xs gamma decays

14 Inclusive V ub (Theory developments) BLNP includes SSF effects whilst LLR & Neubert do not. Interpretation of BaBar lepton endpoint results

15 Inclusive V ub (Theory developments) Dressed Gluon Exponentiation (Einan Gardi & Jeppe Andersen)

16 Inclusive V ub (Theory developments) Ongoing effort toward new sub-leading SF effects that are at order alpha_s (G. Paz ) How to constrain the Weak Annihilation (WA) effect, besides measuring B+/B0 rate separately? (V. Luth) Ferrara presented a model calculation for threshold spectra and fitted their predictions to not fully corrected data of B-factories.

17 Exclusive and form factors

18

19 B  X c l

20 D** at the TeVatron

21

22 Higher resonances, B  D*(n  )l

23 More “inclusive” B  D/D*/D*(n  ) l

24 More “inclusive” B  D/D*/D*(n  ) l

25 Comparison Belle and BABAR  B A B AR and Belle results are nicely consistent “D*l puzzle” : Charged-over-neutral BF ratio does not match lifetime ratio (& isospin):

26 - A non-pert technique without using effective theory

27

28 B   l and B   l with Tagging Semileptonic tags: Hadronic tags: Very clean signal High purity Will improve with higher statistics 41 ± 9 evts hep-ex/

29 Signal efficiency 4x higher than previous untagged BaBar result due to looser neutrino selection cuts Reconstruct q 2 as (p B - p  ) 2  (q 2 ) ~ 0.5 GeV 2 Fit signal and backgrounds in 12 bins of q 2  reduce systematic errors due to bkg BF’s and FF’s. Untagged B   l with “Loose” Reco signal evts Talk by B. Viaud CLEO has also updated their untagged B   l with full data set (14 fb -1 ) Talk by S. Stone

30 CLEO untagged BaBar untagged #BB  10 6 BF(B  )  10 4 CLEO ‘06 untagged  0.15 stat  0.12 sys BABAR ’06 Untagged  0.08 stat  0.10 sys BELLE ’06 had tag  0.26 sta t  0.06 sys HFAG ICHEP ’06 Avg 1.37  0.06 stat  0.06 sys B   l Branching Fractions Belle had. tag

31 BaBar: α BK = 0.52 ± 0.05 ± 0.03 B   l Form Factor and |V ub | LCSR LQCD

32 Overlay of all 4 parameterizations Best-fit FF’s normalized to BGLa Comparison with Other Parameterizations Talk by P. Ball

33 Quenched Unquenched Talk by J. Flynn

34 Talk by I. Stewart “Complex Magic” – Dispersion Relations

35 Other Modes CLEO still competitive with B factories due to higher efficiency at symmetric machine  ’, B factories results for hadronic tags  need more statistics  l from Belle: B (B +  l + ) = (0.44  0.23  0.11  0.00)x10 -4 B (B +  l + ) = (2.66  0.80  0.57  0.04)x10 -4  (B +  l + )/  (B +  l + cl B (B +  l + ) = (0.84  0.27  0.21) x B (B +  l + ) < 1.3 x  l  ’l from BaBar:  l  ’l from CLEO: How to determine B   FF’s ? B factories  ~ 5000 events  Full 4D fit to decay angles not possible  Need guidance from theory

36

37 Form Factors CLEO-c somewhat disagree with FNAL-MILC-HPQCD prediction, Belle  2 28/18 (K) & 9.8/5 (  ) D o  Kℓ & FOCUS LQCD: Aubin et al., PRL94, (2005) ~2.5k signal events 232 signal events Unquenched LQCD Quenched LQCD Simple pole model Kℓ  ℓ Belle q 2 (GeV 2 ) (hep-ex/ ) BELLE: PRL 97, (2006) [hep-ex/ ]

38 CLEO-c form factors for D  Pe FNAL-MILC-HPQCD* D  Ke f + (0)=0.73±0.03±0.07  =0.50±0.04±0.07 D  e f + (0)=0.64±0.03±0.06  =0.44±0.04±0.07 * C. Aubin et al., PRL (2005) DATA FIT (tagged) LQCD DATA FIT (tagged) LQCD Assume V cd = Assume V cs = Belle.. CLEO-c

39 Conclusion A lot of progresses has been made since last CKM workshop both in experiments and in theory, which gave much better understanding of the systematic errors. In some cases this has led to improved precisions, but even if it has not, the errors have become more reliable.