Working Group 3 Summary: V td , V ts , and Friends

1. K Bs B Working Group 3 Summary:Vtd, Vts, and Friends Jeffrey Berryhill Laurent Lellouch Mikolaj Misiak Christoph Paus CKM Workshop, UCSD March 18, 2005

2. K VtdVts* from Rare K Decays: K+→p+nn, KL→p0nn Buchalla Theoretically “Gold-Plated” relations of BFs to lt = Vtd Vts* K+→ p+nn rate ~ |VtdVts*|2 Theory error in |Vtd| extraction from BF ~10% mostly parametric errors from mc, Vcb Only 5% error from scale dependence KL →p0nn rate ~ (Im lt)2 ~ h2 Theory error in h extraction from BF ~3% et al.

3. K K+→ p+nn: Measurement Status Jaffe Blind analysis 3 candidate events in the signal box Background probability = 0.001 (>3s) BNL E787/E949: Stop kaon, measure outgoing pion Aggressively and redundantly veto huge backgrounds SM No new data expected 15% precision improvement from final analysis

4. K Rare K Decays: Summary K+ signal in the right range Interesting SM-like precision is years away

5. K K0 Mixing: Theory Precision

6. K

7. Bs

10. Bs Mixing Measurements Bs CKM fits expect Dms≈ 14-24 ps-1 World average “Amplitude scan” Dms > 14.5 ps-1 Amplitude scan • Fit D*A*cos(Dm t) at fixed Dm • Expect A=1 for real Dm, 0 otherwise • Sensitivity: Dm such that 1.645sA =1 • 95% CL: Dm such that A+1.645sA = 1

11. DØ Bs Mixing in Semileptonics Bs Abbott • BsDsmX (460 pb–1) • Ds fp • Enhanced opposite side m tag • 7037 events (376 tags) • eD2=(1.170.04)% Limit: Dms > 5.0ps–1 @95% CL Sensitivity: 4.6 ps–1

12. BsDs + lepton (e/m) Ds fp, K*K, ppp 4355 events Trigger: 4GeV e/m + track Opposite side flavor tags e,m,jetchargeeD2=(1.430.09)% CDF Bs Mixing in Semileptonics Bs Furic Limit: Dms > 7.7ps–1 @95% CL Sensitivity: 7.3 ps–1 For both CDF+D0, semileptonic decays rapidly lose ct resolution at realistic Dms

13. CDF Hadronic B decays Bs Furic

14. Bs Mixing, Roadmap to Improvement Bs Abbott • More integrated luminosity • Better flavor tagging (same-side K tag) • Improve proper time resolution (event-by-event vertexing) • Hadronic decays matter more for larger Dms • D0 tracking upgrade (add small radius silicon this summer) • DAQ/trigger/offline upgrades • Peril: can present trigger efficiency be maintained at high instantaneous luminosity? D0 projections

15. Friends of Bs mixing: leptonic D decays Bs Ryd CLEO-c CLEO-c measurement of D+ mn Extract f(D+) from D+→mn decay rate 30k fully reconstructed y’’→ D+D- events 8 signal events with missing mass = 0 Can improve to 3% precision for f(D+) f(Ds+) 2% precision expected from y(3770)→Ds+ Ds- running (tn and mn) BF(D+→ mn) = 3.5 ± 1.4 ± 0.6 10-4 f(D+) = 202 ± 41 ± 17 MeV LAT = 225 ± 13 ± 21 MeV D decay constants and their ratios check or bound errors of lattice estimates of B decay constants

16. Friends of Bs Mixing: B mixing and lifetime Bs Hastings Further improvement in B0, B+ lifetime and B0 mixing from B factories Belle D*ln,hadronic 152 M BB Asymmetry vs. |Dt| < 1% B factory precision on lifetime and mixing HFAG average Belle D*ln,hadronic 152 M BB Mixing and lifetimes from B factories could ultimately improve by another 2x

19. Friends of Bs Mixing: recent lifetimes progress Bs Abbott DGs/Gs : new D0 measurement consistent with predictions • New DØ result DGs/Gs=0.21 +0.33-0.45(stat.+syst.) • Constrain tBs=1.39 ps DGs/Gs=0.23+0.16-0.17(stat.+syst.) Tarantino HFAG measurements Predictions Recent predictions and measurements exhibit no serious “lifetime puzzle”

20. Radiative Penguin B Nishida Radiative B decays : penguin diagram Sensitive to New Physics b  s process has been studied. • Branching fraction. • Charge and isospin asymmetry. • Mixing induced CP asymmtery. But,b  d is not observed yet. • suppressed by|Vtd / Vts|2 in SM. • Search for B, has been done. ~ 0.04

21. Search for B , B B Nishida Search for B++ , B00 , B0 Isospin relation B(B(,) ) B(B++ ) = 2(B+/B0)B(B00 ) =2(B+/B0)B(B0 ) Analysis • Severe continuum background. • b  s (esp. B  K* ) background. • Non-negligible BB background. Simultaneous fit to 3 modes (+B  K* ) SM prediction: B(B(,) ) = (0.9-1.8) × 10-6

22. bdg Branching Fractions: Exclusive B Nishida central value 90% C.L. upper limit Combined significance Belle+BaBar = 2.6 s 5s observation in 1-2 years

23. B Bosch

24. B Bosch Inclusive ratio b →dg /b →sg better theory errors for Vtd/Vts, but might need SuperB factory

25. Friends of rg, K*g: Other Penguins Other Penguin Decays B Hollar, Feldmann B →K(*)ll, s ll branching fractions measured by B factories and theory error already dominant More will be learned from distributions and asymmetries B→pll has possibility for observation at B factories (not background limited) rll much harder

26. Challenges A list of future challenges to the Workshop participants.

27. Challenges Bs To the Tevatron: Now that you have a good shovel, break substantial new ground with it for Dms constraints. Upgrades, better tagging, better vertexing, more luminosity, better DAQ, Whatever it takes! The flavor physics community is cheering you on!

28. Challenges Bs To the Lattice community: Raise the “letter grade” above “C” level for fB, BB et al., so that the impact of future Tevatron results is maximized. Andreas Kronfeld To CLEO-c et al.: Continue to keep the lattice community honest!

29. Challenges B To the B factories: Measure a clear signal for B→rg or drive lower limit off the (CKM) map!

30. Challenges B To the heavy quark theory community: Improve and/or realistically bound the impact of penguins on Vtd/Vts et al.The measurements are there and ready to be exploited now!

31. K Challenges To the Kaon physics community: Keep your future projects alive (and Andrzej out of retirement). The small theory errors mean these may ultimately be the best attainable CKM constraints on Vtd and h.