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Highlights From Flavor Physics at

Highlights From Flavor Physics at. Alessandro Cerri. Contents. Introduction Samples and modes Lifetimes & BR CP violation & Mixing Conclusions. Caveat Emptor. The B group at CDF is very active! At the moment we have: 48 “ public ” B physics results 18 since ICHEP ’04

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Highlights From Flavor Physics at

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  1. Highlights From Flavor Physics at Alessandro Cerri

  2. Contents • Introduction • Samples and modes • Lifetimes & BR • CP violation & Mixing • Conclusions

  3. Caveat Emptor • The B group at CDF is very active! • At the moment we have: • 48 “public” B physics results • 18since ICHEP ’04 • 8published (lots of publications in the pipeline!) • Too vast to be covered in 30 minutes! • I made my choices, we can chat offline about your favorite analysis! Other little caveat: • HEP is a ‘large’ community but CDF has been around for years… I will not cover explicitly detector performances and features! • Minimal description of reference information

  4. The basics! • CDF II has collected so far ~0.8 fb-1 out of the delivered Tevatron luminosity • Out of these there are 600 pb-1 available for B physics (tracking detectors restrictions) • Most analyses shown today use between 250 pb-1 and 350 pb-1 of luminosity!

  5. The Tevatron is competitive in HF • B factories program extensive and very successful BUT limited to Bu,Bd • Tevatron experiments can produce all b species: Bu,Bd,Bs,Bc, B**, b,b • Compare to: • (4S)  1 nb (only B0, B+) • Z0 7 nb • Unfortunately • pp 100 mb • b production in pp collisions is so large (~300 Hz @ 1032 cm-2 Hz) that we could not even cope with writing it to tape!

  6. Samples • Good lifetime (~100fs) and mass resolutions (~15 MeV) • Mostly HF-dominated background  well modeled • LARGE: • J/ (dimuon trigger): ~ 1,000,000 J/ • lDX (4 GeV lepton+displaced track) ~ 100,000 lD • Fully hadronic (two displaced tracks) ~ 10,000 B • ~ 1,000,000 D KK

  7. Organizaton of this talk • Time frame: • New results since last users meeting (few exceptions…) • Focus on results which arecomplementaryto/competitivewithB factories • Emphasize the development of tools and techniques at each step

  8. Complementarity to B factories Hep-ex/0505076 • First signal of fully reconstructed Bc • Direct mass measurement!

  9. Branching ratios We have measured several branching ratios… (and many more to come!) http://www-cdf.fnal.gov/physics/new/bottom/031002.blessed-bs-br/ http://www-cdf.fnal.gov/physics/new/bottom/050310.blessed-dsd/ http://www-cdf.fnal.gov/physics/new/bottom/050310.blessed-dsd/

  10. CDF Run II Preliminary 360 pb-1 Sc++ CDF Run II Preliminary 360 pb-1 CDF Run II Preliminary 360 pb-1 Sc0 Lc(2625) Lc(2593) http://www-cdf.fnal.gov/physics/new/bottom/050407.blessed-lbbr/ Branching Rations, continued: Baryons The field to explore is so extensive that we have been ‘stumbling’ upon unobserved signals all over the place, in the ‘easiest’ cases: • First observation of several Lb semileptonic decays that can ‘mimic’ the signal • Estimate the BR based on the observation

  11. b Updated knowledge • Colors: • PDG2004 • CDF contribution beyond current PDG2004 Mass m = 5619.9  1.7 MeV/c2 Lb mass (4.1  2.0) x 10-3 Lc l u (5.5  1.8) % pK + pp < 2.2 x 10-5 Lc+p- p- p+seen Lc(2593) +l u seen Lc(2625)+l u seen Sc++p-l u seen Sc0p+l u seen

  12. BR & Rare decays • Exploit the large B production rate • Measure relative BR (e.g.  to J/K) to factor out absolute  and luminosity measurements • SM: BR(Bs) <3.8E-9 • Sensitive to new physics! Publ: PRL 93, 032001 2004 Update: Hep-ex/0502044 PRD 68, 091101 2003

  13. Lifetimes • Lifetimes are an important experimental reference: • Overlap with B factories  understanding of detector/trigger/analysisbiases • Further test on species not produced at B factories • Systematic shift in HQE predictions? • We can test this: samples are at hand! Experiment Theory C. Tarantino, hep-ph/0310241 Oct 2003

  14. Lifetimes: fully reconstructed hadronic modes • Testbed for our ability to understand trigger biases • Large, clean samples • Prerequisite for mixing fits! (B+) = 1.661±0.027±0.013 ps (B0) = 1.511±0.023±0.013 ps (Bs) = 1.598±0.097±0.017 ps Systematics (m) KK http://www-cdf.fnal.gov/physics/new/bottom/050303.blessed-bhadlife/

  15. 260 pb-1 13,300 Signal events Lifetimes: semileptonic http://www-cdf.fnal.gov/physics/new/bottom/050224.blessed-bsemi-life/ • Largest statistics B sample • More complicated background • Full statistics sample still under study. Statistical uncertainty expected: @ ~400 pb-1 • Our understanding of sample composition tested with ‘inclusive lepton’ sample: • Working on systematics! (B+) = 1.653±0.029±0.032 ps, (B0) = 1.473±0.036±0.054 ps (B+)/(B0) = 1.123±0.040±0.040

  16. CDF can probe HQET and constrain it! Constraining HQET tools for Vcb Moments: kinematic parameters in BlXc decays Non-leptonic mass in BlXc HQET Parameters Mean RMS PRDRC 71, 051102 2005

  17. CP Violation & Mixing

  18. CP: Bhh modes • Difficult competition with B factories for t-dependent tagged measurements • Interesting B physics measurement of BR and  • Signals overlap within mass resolution • Exploit kinematic handles and dE/dX to disentangle components in a combined fit: • M • the two track’s momentum imbalance • dE/dX • With perfect particle ID, separation • would be ’only’ ~60% better

  19. CP: hh modes • Good agreement with B factories • First measurement ever of BsKK http://www-cdf.fnal.gov/physics/new/bottom/040722.blessed-bhh/ http://www-cdf.fnal.gov/physics/new/bottom/040624.blessed_Lb_hh_limit/

  20. Hep-ex/0502044 • bsss transitions are ‘misbehaving’ at B factories • …CDF II can look at them too. We started from K: CP: sss • …With the advantage of being able to look at Bs too:

  21. ms>>md • Different oscillation regime  Amplitude Scan Bs Mixing 101 Perform a ‘fourier transform’ rather than fit for frequency B lifetime A  ms [ps-1]

  22. Bs Mixing Ingredients Proper time resolution Flavor tagging Signal-to-noise Event yield

  23. Bs Mixing: tagging performance

  24. Bs Mixing: semileptonic • BsDsl • Ds (435594 3.1 ) • DsK*K (175083 0.42 ) • Ds (157388 0.32) ms> 7.7 ps-1 @ 95% CL Sensitivity: 7.4 ps-1 Reach at large ms limited by incomplete reconstruction (ct)!

  25. Bs Mixing: hadronic • BsDs • Ds (52633 1.8) • DsK*K (25421 1.7) • Ds (11618 1.0) ms> 0.0 ps-1 @ 95% CL Sensitivity: 0.4 ps-1 Low statistics, but promising!

  26. Combined Bs mixing limit ms> 7.9 ps-1 @ 95% CL Sensitivity: 8.4 ps-1 ms> 14.5 ps-1 @ 95% CL Sensitivity: 18.6 ps-1

  27. Bs Mixing Perspectives • Analysis is pretty much defined! We know where we can improve: • What happens for extremely large values of ms? • We have a backup plan… • Statistics • Data (brute force) • D2 : • Additional taggers (SSK, OSK…) • Improve existing algorithms • Proper time resolution

  28. URA thesis award! Probing at large ms: / • BsJ/ • B VV, mixture of CP even/odd separate by angular analysis • Combine two-lifetime fit + angular DGs=GH-GL • SM DGs/Gs=0.120.06 (Dunietz, Fleischer & Nierste) • Indirect Measurement of Dms few ps-1 in ms ! PRL 94, 101803 2005

  29. Conclusions • 48 public results so far: lots of successful h.f. physics! • Well established samples and techniques • Competitive with and complementary to B factories • Infrastructure, tools and first measurements of Bs mixing are ready! • Accumulating statistics is now crucial! • …still much more to come!

  30. Backup Slides

  31. Results Omitted • Taggers calibration • Semileptonic (050224) • Hadronic (050224) • B mixing with SST (040812) • Mixing with combined taggers (040812) • NN based JQT on semileptonics (050303) • Improved JQT in semileptonics (040812) • Likelihood based SET (040812) • Likelihood based ST (040722) • Relative BR and CP asym. For D0KK,K, (031211) • b lifetime (030710) • X(3872) (040624, 040920, 050324) • M(Ds-D+) (030320) • D1 and D2 masses (040805) • B hadrons masses (040428) • Pentaquark searches (040819, 040428,040219,040428) • J/ inclusive cross section (030904) • Direct charm cross section (030403) • (Wrong sign) D0K PR (040930) • QCD: • Inclusive B jet production (Apr ‘05) • Bbbar dijet production (Apr ’05)

  32. Tracking: • COT (central wire chamber) • ISL (Intermediate Silicon Layers) • SVX II (silicon vertex detector) • Layer 00 (Innermost layer of the Si detector, glued to the beam pipe) • PID: • dE/dX in COT • TOF (Time of flight detector) • Lepton ID: • Muons: CMU, CMX, CMP • Electrons: CEM (EM calorimeter) • CPR (pre-shower detector)

  33. Exciting results in the B sector Bd,shh Bu,d,slD*/+/0X Bu,dlD**X BsDs BsK Bs Bs(2s) BcJ/ BcJ/X • Despite the great success of B factories, there is room for interesting B physics at an hadron machine! • Lifetimes • Branching ratios • Rare decays • CP violation • Probing of HQET • Mixing!

  34. We also have Baryons! • Nice probe of HQET • Inaccessible to b factories • Lifetimes • BR • CP violation? • blcX • bJ/ • bc • bph

  35. D0K//KK • D0 • D+K • D*D0 • J/ • D**D • Large statistics: charm factory! • Mostly prompt production • Many interesting questions: • Production (, correlations, mechanisms) • Branching ratios • CP violation • Masses and widths (excited states)

  36. More ‘exotic’ stuff Several nice results: • Baryons • X(3872) • Mass • Lifetime • Pentaquarks … I don’t have to cover them, but you can look at: http://www-cdf.fnal.gov/physics/new/bottom/bottom.html

  37. Production HbX in 37 pb-1 of data! PRD 71, 032001 (2005) PRL 91, 241804 (2003)

  38. Complementarity: Bc http://www-cdf.fnal.gov/physics/new/bottom/050330.blessed-bc-jpsimu/ • Mode that gave the first evidence of the Bc (CDF Run I) • Large yield, no clean resonance though! 106 events 46.07.3 events • First signal of fully reconstructed Bc • Direct mass measurement! Hep-ex/0505076

  39. CDF Run II Preliminary 360 pb-1 Sc++ CDF Run II Preliminary 360 pb-1 CDF Run II Preliminary 360 pb-1 Sc0 Lc(2625) Lc(2593) …incidentals! The field to explore is so extensive that we have been ‘stumbling’ upon unobserved signals all over the place! Lc(2625) Lc(2593) Sc++,+,0 • First observation of several Lb semileptonic decays that can fake the signal • Estimate the BR based on the observation

  40. Lifetimes • Critical testbed of HQE • HQE vastly used for phenomenology predictions • b-hadrons lifetime ratios accurately predicted • Important experimental reference • Overlap with B factories  understanding of detector/trigger/analysisbiases • Further test on species not produced at B factories

  41. http://www-cdf.fnal.gov/physics/new/bottom/040428.blessed-lft2/http://www-cdf.fnal.gov/physics/new/bottom/040428.blessed-lft2/ Lifetimes: J/ modes • This was the starting point: • Clean unbiased sample • Precision measurement • Reference for biased (e.g. displaced track) triggers • Crucial test of our understanding of: • Detector • Analysis technique • Sample composition

  42. HQET: baryon lifetimes and B moments B lifetimes  Vcb Dominant uncertainty comes from HQET extraction! CDF can probe HQET and constrain it! Probing: b lifetime C. Tarantino, hep-ph/0310241 Oct 2003 LO NLO LO NLO LO NLO http://www-cdf.fnal.gov/physics/new/bottom/030710.blessed-lambdab-lifetime/

  43. Bhh kinematics

  44. Extracting  from Bhh Fleischer Hep-ph/9903456 • Measure ACP(BsKK), ACP(Bd): 4 parameters: • With each asimmetry: Where d and  are different for Bs and Bd, but related under U-spin by:

  45. Extracting  from Bhh Fleischer Hep-ph/9903456 • Assuming also d=, s=0 we can constrain to the BKs value and constrain simultaneously (,,d,) • SU(3) breaking of the order of 10-15% will lead to systematic effects on this determination of the order of 3º This method requires measuring ACP(t) for BsKK… Rather unlikely at CDF

  46. Extracting  from Bhh London & Matias Hep-ph/0404009 • Assuming also SU(3) (dd= ds, d=s) we have 3 unknowns (dd, d,) and 3 measurements (including the value of sin2)  we can determine  • SU(3) breaking effects are parameterized as well

  47. CP: K BR systematics ACP systematics Hep-ex/0502044

  48. bsss

  49. It’s an Asymmetry measurement!! • Reconstruct signal • Hadronic: • good momentum resolution • low statistics • Semileptonic: • worse momentum resolution • higher statistics • Determine “time” of Decay • measure decay length • apply boost • Sort the mixed from unmixed via b charge at production and decay • S = Nmix+Nunmix • D = “Dilution” = 1-2Pmistag • S  SD2 • Fix m and fit A • Scan vs m Bs Mixing 101 K K  Ds  Bs

  50. K  K Ds l l Bs Bs Mixing: proper time • Samples (N, S/B) • Proper decay length resolution K K  Ds  Bs

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