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B physics: new states, rare decays and branching ratios in CDF Vyacheslav Krutelyov Texas A&M University For CDF Collaboration July 1, 2004 BEACH04 Chicago,

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Presentation on theme: "B physics: new states, rare decays and branching ratios in CDF Vyacheslav Krutelyov Texas A&M University For CDF Collaboration July 1, 2004 BEACH04 Chicago,"— Presentation transcript:

1 B physics: new states, rare decays and branching ratios in CDF Vyacheslav Krutelyov Texas A&M University For CDF Collaboration July 1, 2004 BEACH04 Chicago, IL

2 7/1/04 S. Krutelyov B physics: new and rare BEACH04 2 Outlines  CDF Run2  Detector  Triggers  Searches  B s(d)       D 0       Measurements (successful searches)  X(3872)  B +  J/    B s   and pentaquarks  See talks by S.D’Auria and D.Litvintsev

3 7/1/04 S. Krutelyov B physics: new and rare BEACH04 3 Tevatron performance  As you know the Tevatron is working very well this year  Record initial luminosity = 84  10 30 cm -2 s -1 (92  10 30 cm -2 s -1 to CDF)  Detector efficiency ~85-90%  ~450pb -1 on tape  100-200+ pb -1 used for analysis so far

4 7/1/04 S. Krutelyov B physics: new and rare BEACH04 4 CDF Run2.   s=1.96TeV σ(Inelastic)~60mb. ℒ ~7  10 31 cm -2 s -1 (~400pb -1 good recorded)  Plan: ~8  10 31 cm -2 s -1 (Run2a); ~2  10 32 cm -2 s -1 (4-8/fb Run 2)  1.7MHz collision  20kHz L1 trigger  350Hz L2  60Hz L3/logging rate.  ~80% L1 (~1/3 at L3) of the trigger (bandwidth) are B physics  Better silicon coverage (  2), muon detection, improved tracking.  Better triggers: lower track p T, higher efficiency. Run2 vs Run1  SVX II (5layer) silicon strip det  svx+IP ~40  m COT tracker drift chamber  p T /p T 2 ~0.1%  p T /p T 2 ~1.5%(L1/XFT) CMU muon det (drift cham) p T >1.5GeV |  CMP muon det (drift cham + scint) p T >2.5GeV |  2 ft steel CMX muon det (drift cham + scint) p T >2GeV 0.6<|  

5 7/1/04 S. Krutelyov B physics: new and rare BEACH04 5 Triggers used  Dimuon trigger  p T >1.5GeV,  p T >2GeV, 0.6<  1  p T, , muon ID used to cut on tracks  Used for    X)  Two Track Trigger  p T >2GeV,   p T, , d 0 info used to cut on 2 tracks  Used for: B,D  hadrons ; D   All are input to the various Level-3 triggers That use the offline quality information primary vertex secondary vertex impact parameter ~ 1 mm b, c decays  Semileptonic trigger  p T, , d 0, muon ID used to cut on tracks  Used for ,D,    X)  no results presented in this talk

6 7/1/04 S. Krutelyov B physics: new and rare BEACH04 6 Triggers used  Dimuon trigger  p T >1.5GeV,  p T >2GeV, 0.6<  1  p T, , muon ID used to cut on tracks  Used for    X)

7 7/1/04 S. Krutelyov B physics: new and rare BEACH04 7 Triggers used  Two Track Trigger  p T >2GeV,   p T, , d 0 info used to cut on 2 tracks @L2  Used for: B,D  hadrons ; D   primary vertex secondary vertex impact parameter ~ 1 mm b, c decays

8 7/1/04 S. Krutelyov B physics: new and rare BEACH04 8 B(D)   : Theoretical motivations. Current limits.  Flavor Changing Neutral Current. Loop contribution only in SM.  Br SM (B s  μ + μ - )=(3.4±0.5)  10 -9  Br SM (B d  μ + μ - )=(1.00±0.14)  10 -10 (hep-ph/0303060)  Br SM (D 0  μ + μ - )~3*10 -13 (GIM suppressed)  Only upper experimental limit exists:  Br exp (B s  μ + μ - )<2.0  10 -6 90% C.L. CDF RunI @100/pb.  Br exp (B d  μ + μ - )<1.6  10 -7 90% C.L. Belle ‘03 @78/fb.  Br exp (D 0  μ + μ - )<4.1(4.2)*10 -6 90% C.L. BEATRICE(E771)  Limits are far away from the SM value: can test for a possible new physics.  MSSM: Br( B  μ + μ - ) enhanced by tanβ>10 terms ~tan 6 β. Up to 100 over the SM prediction.  R-parity violating models give tree level contributions. Not heavily constrained by other observables.  Can be seen in Run2 (esp. B s   )  Other models enhance less. E.g., universal extra dimensions. Up to +70% for B s  μ + μ - ’ i23  i22    b s RPV mSUGRA,SO(10)

9 7/1/04 S. Krutelyov B physics: new and rare BEACH04 9 D 0   search  1.012  1.43·10 -3  Use D *±  D 0 π ± tagged events  Use D 0      as a normalization mode.  Blind from  ID in 1.840<m  <1.882 GeV  Cuts:  |d 0 (μ,π)|>120μm, |d xy (D 0 )|<150μm  Δφ(μμ)>0.085  Background:  combinatorial (from right sideband) – expect 1.5±0.7  misidentification (punch-through/decay) – expect N(D 0      )  P(misID) 2  0.3±0.1

10 7/1/04 S. Krutelyov B physics: new and rare BEACH04 10 D 0   search  B(D 0   )<2.4  10 -6 @ 90% C.L.  B(D 0   )<3.1  10 -6 @ 95% C.L.  This result improves on the previous limits by ~  2 (4.1  10 -6 from BEATRICE, and 4.2  10 -6 from E771 at 90% C.L.) 69pb -1

11 7/1/04 S. Krutelyov B physics: new and rare BEACH04 11 Br(B s(d)  μ+μ-) measurement.  Expect to detect at most few events that might only look like B s(d)  μ+μ–  SM predicts 0 events  really a “search”  Don’t look at the data signal region (blind search)  Signal inside 5.169<M   GeV/c 2 (  3  window   demonstrate understanding of background events  accurately estimate  (acceptance) and  (efficiency)  intelligently optimize cuts CL=90% upper limit on for n obs and n bg 171pb-1 or 10 trillion collisions only Run1  Bs =0.9  b for p T  s >6 GeV/c, |y|<1 (use this as a baseline selection) 3% (CMU&CMP Run1) 25% Run1 Dimuon trigger and p T >6GeV baseline sample: 2940 events

12 7/1/04 S. Krutelyov B physics: new and rare BEACH04 12 Signal & Background  Need to select discriminating variables that leave most of the signal and remove most of the background. P T  PTPT  x y B s    R < 1 (  < 57 o ) PTPT   P T vtx  Most Promising Discriminating Variables – Invariant mass – c  :  2D lifetime  c –  :  (p T B ) –  (vtx) – Isolation: Largest expected background: gluon splitting g  bb   

13 7/1/04 S. Krutelyov B physics: new and rare BEACH04 13 Optimization Results  Optimize on (M , c , , Iso) to get the best expected limit  (c , ,Iso) = (>200 mm, 0.65) and mass window  80 MeV around world avg Bs(d): 5.369 GeV (5.279 GeV)  Bs(d):  total = (2.0  0.2)% (  6.6%,  total  30%)  Accepted bgd  = (6  2) fb  Expected bacground in 171pb -1 = 1.1  0.3 events Poisson prob

14 7/1/04 S. Krutelyov B physics: new and rare BEACH04 14 Observed limits BR(B s  μ + μ  ) < 5.8x10  7 90% C.L. (7.5x10  7 95% C.L.) 3 times better than Run I (previous world best) BR(B d  μ + μ  ) < 1.5x10  7 90% C.L. (1.9x10  7 95% C.L.) slightly better than (1.6x10  7 90% C.L., just published) B-factory/Belle result

15 7/1/04 S. Krutelyov B physics: new and rare BEACH04 15  for SUperSYmmetry (@95% C.L.) 7.5  10 -7 R. Arnowitt et al., PLB 538 (2002) 121, new plot by B.Dutta R-parity violating R. Dermisek et al., hep-ph/0304101 SO(10) significant New limit excludes significant amounts of the previously allowed SUSY models parameters (more to go) Dark matter allowed region new exclusions @95% CL

16 7/1/04 S. Krutelyov B physics: new and rare BEACH04 16 Spectroscopy – Exotic States X(3872)  New narrow state observed first by Belle in decay modes J/      Charmonium state not expected near mass peak.  D* Dbar deuteron-like molecule ?  CDF confirms X in 220pb -1  Preference for M(   ) > 500MeV  670±90 candidates, sign.~ 12   Mass scale using  (2S) peak

17 7/1/04 S. Krutelyov B physics: new and rare BEACH04 17 X(3872): Long-lived fraction  Long-lived fraction:  F X(3872) =16.1  4.9  2.0 %  cf F  (2S) = 28.3  1.0  0.7 % CDF II

18 7/1/04 S. Krutelyov B physics: new and rare BEACH04 18 B  J/    Cabibbo-suppressed decay B +  J/    Br Expected to be 5% relative to Br(B +  J/  K + )  Br(B +  J/  + )/Br(B +  J/  K + )=4.2  0.7% PDG02  Signal selection  p T (B + )>6.5GeV, p T (K + )>2GeV, L xy >200  m

19 7/1/04 S. Krutelyov B physics: new and rare BEACH04 19 Summary  Great physics results are coming in from CDF  Br(B s   )<5.8 x 10 -7 at 90% C.L.  Br(B d   )<1.5 x 10 -7 at 90% C.L.  Br(D   )<2.4 x 10 -6 at 90% C.L.  X(3872) confirmation  Long-lived fraction F X(3872) =16.1  4.9  2.0 % . accepted/published by PRL

20 7/1/04 S. Krutelyov B physics: new and rare BEACH04 20

21 7/1/04 S. Krutelyov B physics: new and rare BEACH04 21 BACKUP SLIDES

22 7/1/04 S. Krutelyov B physics: new and rare BEACH04 22 Data Samples —OS+ : opposite-sign muon pairs, ctau > 0 our signal sample – not used for xchecks — OS- : opposite-sign muon pairs, ctau < 0 — SS+ : same-sign muon pairs, ctau > 0 — SS- : same-sign muon pairs, ctau < 0

23 7/1/04 S. Krutelyov B physics: new and rare BEACH04 23 R. Arnowitt et al., hep-ph/0203069, PLB 538 (2002) 121 mHmH  Overlap with measured δa μ (BNL) in mSUGRA parameter space.  Overlap with dark matter=LSP allowed region.  Eliminate large parameter space (~ all for tanβ>40), with Br(B s  μ + μ - )~10 -8 in Run2 (15/fb) Motivations: B s  μ + μ - (mSUGRA)

24 7/1/04 S. Krutelyov B physics: new and rare BEACH04 24 _ ’ i23  i22    b s c b l s  l  R. Arnowitt et al., hep-ph/0203069, PLB 538 (2002) 121 15 fb  1 2 fb  1 e.g., W TRPV = ijk L i L j E k  ’ ijk L i Q j D k  ’’ ijk U i D j D k R P Violation: Br vs. m 1/2

25 7/1/04 S. Krutelyov B physics: new and rare BEACH04 25 B  hh PR plot now ~1K events with 180/pb

26 7/1/04 S. Krutelyov B physics: new and rare BEACH04 26 M  [GeV/c 2 ]   CDF, PRD 57, 3811 (1998)  Ldt = 98 pb  1 (~5 x 10 12 collisions) B d : 5.205-5.355 GeV/c 2 B s : 5.300-5.450 GeV/c 2 N obs = 1 with 5.344 GeV/c 2 (consistent with an expectation from the Standard Model backgrounds) Br(B d   ) < 8.6 x 10  7 (95% C.L.) Br(B s   ) < 2.6 x 10  6 (95% C.L.) B d(s)   : Run I Results


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