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Recent Charm Physics Results at. Alessandro Cerri. Outline. Introduction CDF Charm Cross section and yields D** properties D** terminology Masses and widths of narrow states D** in semileptonic B decays D 0 Cabibbo suppressed decays: Theory intro Decay BR Direct CP
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Recent Charm Physics Results at Alessandro Cerri
Outline • Introduction • CDF • Charm Cross section and yields • D** properties • D** terminology • Masses and widths of narrow states • D** in semileptonic B decays • D0 Cabibbo suppressed decays: • Theory intro • Decay BR • Direct CP • Prospects for DCD mixing • X(3872) • Covered in other talks • Near term prospects • D+ BR and CP violation • Conclusions
Plenty of clean charm! Swamped by Charm CDFII Published PRL 91, 241804 (2003).
D**: Introduction • Plenty of D**: Dj narrow, wide, radial, orbital, resonant, nonresonant… • HQET predicts splitting of states vs mQ • Narrow states are widely observed objects • The large statistics of charm at CDFII gives access to D** • What can we learn from these samples?
Prompt D1,2 Prompt D1,2 D**0 Properties D1,2 D*+- D*+D0+ D0K-+ D2 D+- D+K+-- • Huge sample of narrow D** resonances • Competitive in measuring prompt D** properties! • … and non prompt Secondary D**
D**0 mass from prompt charm M(D1)-M(D*)=411.70.70.4 MeV M(D1)=2021.70.70.6 MeV (D1)=20.01.71.3 MeV M(D2)-M(D*)=594.00.60.5 MeV M(D2)=2021.70.70.6 MeV (D2)=20.01.71.3 MeV New CDFII Result
D2 Mass D1 Mass Improved Statistics and Systematics! D1 Width D2 Width
CP Violation in the c sector • CP in c is expected to be small • SM: 0.1-1% • Direct CP would be a hint of non SM mechanisms! • Two methods are being explored to tackle this: • Direct CP: D*+D0[fCP]+ • Mixing: • (D0K+-)/(D0K-+)
Precision width ratios • Use of K as a reference helps dealing with: • Charge/particle asymmetry • Production rate and spectra • Detector acceptance • Interesting measurement • A good benchmark for ACP! Submitted for publication www-cdf.fnal.gov/physics/new/bottom/ 040428.blessed-bphik_acp/
Submitted for publication www-cdf.fnal.gov/physics/new/bottom/ 040428.blessed-bphik_acp/ Direct CP asymmetry Best single exp. (CLEO02): A(D0KK): 0.02.20.8 % A(D0): 21.93.20.8 % PDG 2004 averages: A(D0KK): 0.51.6 % A(D0): 2.12.6 % On our way towards time dependence…
Plan for Doubly Cabibbo Suppressed decays We expect about 2.8 DCS decays per pb-1! (and right now we have ~250pb-1) Key will be being able to control systematics and pollution from other D decays (using kinematics+PID)
D+ Dalitz Properties • Large statistics gives access to detailed features! • We will soon improve the knowledge of BR(D++--) • Theory predicts that direct CP asymmetry could be O(10-3) • [hep-ex/9612005] • E792: -0.0170.042 [hep-ex/9612005] CDFII PR plots www-cdf.fnal.gov/physics/new/bottom/040422.dplus/
Conclusions • CDF II is a successful charm factory! • Unprecedented clean and large statistics charm samples • New and exciting CP results in the charm sector • Cross sections and prompt fractions • Relative lifetimes • Direct CP • Expect more soon! • BR and CP in D+ • DCS decays of the D0
CDF II • Renewed detector & Accelerator chain: • Higher Luminosity higher event rate • Detector changes/improvements: • DAQ redesign • Improved performance: • Detector Coverage • Tracking Quality • New Trigger strategies for heavy flavours: displaced vertex trigger • pp 50mb • bb 0.1mb • cc 0.025 mb
D+ mass vs Pt D*-D0 mass vs Pt D** massBackup: mass stability D0 width vs Pt D0 mass vs Pt
CDFII Result PRL 93, 072001 (2004) August 2003 X(3872) • Properties: • ~10 evidence in BK+X (35.76.8 events) • Mass: 3872.00.60.5 MeV • Signal is at high (>500 MeV) di-pion mass • Width: compatible with experimental resolution ( < 2.3 MeV at 90% C.L.) • ??? Who ordered this ??? • DD* molecule, charmonium [(13D2)] or ??? Belle 304M B’s (2S) ? Events/10 MeV M(J/+-)M(J/) GeV • Shortly afterwards CDF observes: • 73090 candidates in 220pb-1 • Mass: 3871.30.70.4 MeV • High di-pion mass • So we went back and started investigating production: • Most of our X(3872) are prompt September 2003
New CDFII Result www-cdf.fnal.gov/physics/new/bottom/ 040624.blessed-xlonglived/ xlonglivedWWW.ps X(3872) Prompt fraction Non-Prompt Fraction: Non-Prompt Fraction: 16.14.9 (stat.)2.0 (syst) % 28.31.0 (stat.)0.7 (syst) %