B physics outlook at

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B physics outlook at

• Tara Shears

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Outline

• B physics at CDF
• production
• triggering
• B physics outlook ( some current results)
• Mixing
• CP violation
• Rare decays / new physics
• Summary

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B production at CDF
Similar production cross-sections to LHC bb
production cross-section high So is charm So is
inelastic All B species produced in same ratio
as LHC ? Bs sector can be explored before LHCb
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Heavy flavour triggers
Dilepton 2 leptons several Pt thresholds
Lepton displaced track Pt (lepton)gt4 Pt(trk)gt2
120mmltd0lt1mm
2 displaced tracks Pt(trk)gt2 GeV, SPt gt5.5 GeV
120mmltd0lt1mm
SVT
d0
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Displaced track trigger (SVT)

• Level 2 displaced track trigger
• ?(d0) 47 mm
• 15 ms operation
• online primary vertex finding, tracking
• trigger on displaced tracks (large d0)
• n.b. cross-sections grow with luminosity.

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Data taking outlook
4.4 8.5 fb-1 forecast by end 2009 2.5 5 fb-1
by mid-2007
600 pb-1 on tape now Typically ? 350pb-1 analysed
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Physics

• Focus on projected CDF B physics highlights B0s
  mixing, CP violation, rare decays
• Taken from yellow book hep-ph/0201071
• Show current achievements
• Translate this into future expectation where
  possible

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B0s mixing goals
Needed prior to CP violation measurements Within
2fb-1 CDF should cover SM allowed
range Sensitivity originally estimated as
function of eD2 (originally 11.3) Lifetime
resolution st(45 fs) Yield (25000 75000) SB
(12 21)
xs of 70 Dms of 45 SM Dms lt 24.6 ps-1
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Mixing status now
360 pb-1 900 Bs ? Dsp eD2 1.1 0.2 st
100 fs 7700 Bs?Dsln eD2 1.4 0.1 st larger
(missing n)
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Mixing outlook
Mixing reliant on efficiency, dilution, time
resolution Work ongoing to improve tagging,
yields, decay time resolution Baseline eD2
1.6 st 67 fs Stretch eD2 2.6 st 47 fs
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CP violation goals
B0s mixing
Via ACP of B0 ?pp, K p B0 ? D0K B0s ? DsK
B0 ? J/y K0s B0 ? fK0s B0 ? J/yf for New Physics
(ACP small in SM)
R. Fleischer, Phys. Lett. B459 306 (1999)
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CP violation now
180pb-1 analysed ACP(B?p K-) -0.04 0.08
0.01 ACP (B?fK0s) -0.07 0.17 0.03-0.02 (47
events) hep-ex/0502044
Triggered by SVT ID via dE/dx or ToF information
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CP violation outlook
Yellow book predictions for 2fb-1 sin2b measured
to 0.13 ?0.076 Assumes eD2 3 ?7.8 g
measured to 0.1 Error on ACP in B ? pp as fn.
lumi Much work underway to improve tagging and
event yields before these targets can be met.
(Time dependent ACP ? ACPDIR,ACPMix)
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Rare decay goals

• Aims of run 2
• Observe B ? mmX
• Observe radiative decays
• Eg. B ? K0g (SM BR 10-7)
• Stringent limits on B ? mm (SM br 10-10)
• Deviations from SM could signal New Physics

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Rare decays now
Bd/Bs ? mm 171 pb-1 BR(Bs ? mm) lt 5.810-7
_at_90CL Work ongoing in other modes
PRL 93, 032001 2004
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Rare decay outlook
In 2fb-1 B ? mm limit outlook Expected
observation of B ? K0g Yellow book predicts
60 events (for BR B ? K0mm 1.5 x10-6) B ?
mmX Yellow book predicts 100-300 B ? mmK,
400-1100 B0 ? mmK0
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Summary

• CDF projected results by 2009
• B0s mixing measured (for all SM values of Dms)
• Measurements of b and g in unitarity triangle to
  0.1
• Observation of rare decay modes and indirect test
  of New Physics production
• Note all forecasts dependent on reaching
  predicted performance, receiving planned
  luminosity

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Backup slides
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COT
Nucl. Instrum. Meth. A526 249, 2004 96 layers,
radii 0.3-1.4m 4 axial superlayers (12 wires) 4
stereo superlayers (35 mrad) 200mm hit
resolution Dpt/pt (0.7 ? 0.1pt) dE/dx for
e/p/K/p 1.2s p/K if ptgt2 GeV
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Silicon
750 000 channels! Impact parameter resolution 13
40/pt mm Layer00 2cm radius, single sided SVX
2.5-10cm radius, 5 layers, double sided ISL
20-30cm radius, 1-2 layers, double sided
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Trigger system
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(thanks to Rolf Oldeman)
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Bs mixing

• In practice use amplitude scan method
• introduce amplitude to mixing probability
  formula
• evaluate at each Dm point
• Amplitude1 if evaluated at correct Dm
• Allows us to set confidence limit when
• 1.645s1

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Mixing systematics
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Bs yields