People working on this:
Alan Schwartz,
Bostjan Golob
For a complete list of references click
here
Notation:
the mass eigenstates are denoted
D 1 ≡ p|D0> +
q|D0> and
D 2 ≡ p|D0> −
q|D0>;
R D is the ratio of magnitudes of D0 → f
and
D0 → f
amplitudes;
δ and δKππ are strong phase differences
between
D0
→ f and D0 → f amplitudes, and
φ is a weak phase difference.
The mixing parameters are defined as
x ≡ (m2 − m1)/Γ and
y ≡ (Γ2 − Γ1)/(2Γ), where
Γ = (Γ1 + Γ2)/2.
In the absence of CP violation, our convention is
x = (mCP+ − mCP−)/Γ,
y = (ΓCP+ − ΓCP−)/(2Γ), and
δ =
δ D0
→ K+n(π)
−
δ D0 → K+n(π) .
The following measurements and their world averages are presented here:
D0 → K+l− ν results for R M ≡ (x2+y2)/2.
Year | Experiment | Result | Comment | |||||
---|---|---|---|---|---|---|---|---|
1996 | FNAL E791 | R M = (0.11 +0.30 −0.27 +0.00 −0.014 )% | 500 GeV π −N interactions (2 × 1010 events) | |||||
2005 | CLEO II.V | R M = (0.16 ± 0.29 ± 0.29 )% | 9.0 fb−1 near Υ(4S) resonance | |||||
2004 | BaBar | R M = (0.23 ± 0.12 ± 0.04 )% | 87 fb−1 near Υ(4S) resonance | |||||
2007 | BaBar | R M = (0.004 +0.070 −0.060 )% |
|
|||||
2008 | Belle | R M = (0.013 ± 0.022 ± 0.020 )% | 492 fb−1 near Υ(4S) resonance | |||||
COMBOS average |
|
|
Plot of average (click on for high resolution):
D0 → K+ K−, π+ π−, K+ K− K0 results for: y CP ≡ [Γ(CP+)/<Γ>]−1 = (1/2)(|q/p| + |p/q|) y cosφ − (1/2)(|q/p| − |p/q|) x sin φ, and A Γ ≡ [τ(D0 → K+ K−) − τ(D0 → K+ K− )] / [τ(D0 → K+ K−) + τ(D0 → K+ K− )] = (1/2)(|q/p|−|p/q|) y cosφ −(1/2)(|q/p|+|p/q|) x sin φ .
Year | Experiment | Result | Comment | |||||||
---|---|---|---|---|---|---|---|---|---|---|
1999 | FNAL E791 | ΔΓ = (0.04 ± 0.14 ± 0.05 ) ps −1 | 500 GeV π −N interactions (2 × 1010 events) | |||||||
2000 | FOCUS | y CP = (3.42 ± 1.39 ± 0.74 )% | γN interactions (1 × 106 reconstr. D → K n(π) decays) | |||||||
2002 | CLEO II.V | y CP = (−1.2 ± 2.5 ± 1.4 )% | 9.0 fb−1 near Υ(4S) resonance | |||||||
2009 | Belle |
|
673 fb−1 near Υ(4S) resonance, D → (K+K−) K0 decays | |||||||
2012 | LHCb |
|
29 pb−1 at √s = 7 TeV (LHC 2010) | |||||||
2012 | BaBar |
|
|
|||||||
2012 | Belle |
|
976 fb−1 (full Belle data set) | |||||||
COMBOS average |
|
|
Plot of y CP average (click on for high resolution): Plot of A Γ average (click on for high resolution):
D0 → K+ π − results for: R D, x' ≡ x cosδ + y sin δ, y' ≡ y cosδ - x sin δ, and R B ≡ R D + y' √ R D + (x2+y2)/2 . These results assume no CPV; for results allowing for CPV click here
Year | Experiment | Result | Comment | ||||
---|---|---|---|---|---|---|---|
1998 | FNAL E791 | RB = (0.68 +0.34 −0.33 ± 0.07)% | 500 GeV π −N interactions (2 × 1010 events) | ||||
2000 | CLEO II.V |
|
9.0 fb−1 near Υ(4S) resonance | ||||
2005 | FOCUS |
|
γN interactions (1 × 106 reconstr. D → K n(π) decays) | ||||
2006 | Belle |
|
400 fb−1 near Υ(4S) resonance | ||||
2007 | BaBar |
|
384 fb−1 near Υ(4S) resonance | ||||
2008 | CDF (Run II) |
|
1.5 fb−1 at √s = 1.96 TeV (Tevatron) | ||||
2012 | LHCb |
|
1.0 fb−1 at √s = 7 TeV (LHC pp) |
D0 → K+ π − π 0 and K+ π − π + π − results for: R B, R M, <R D>, and α<y'>, where <…> denotes a quantity integrated (or averaged) over the selected phase-space region of the Dalitz plot, and α is a suppression factor in the range (0,1) arising from strong phase differences over the Dalitz plot. For D0 → K+ π − π 0 there is a strong phase difference δKππ (analogous to δ in D0 → K+ π − decays): x" ≡ x cosδKππ + y sin δKππ, y" ≡ y cosδKππ - x sin δKππ. These results assume no CPV.
Year | Experiment | Result | Comment | |||||
---|---|---|---|---|---|---|---|---|
2005 | Belle |
|
281 fb−1 near Υ(4S) resonance | |||||
2006 | BaBar |
|
230.4 fb−1 near Υ(4S) resonance | |||||
2006 | BaBar |
|
230.4 fb−1 near Υ(4S) resonance | |||||
2008 | BaBar |
|
384 fb−1 near Υ(4S) resonance |
D0 → K0S π+ π − and D0 → K0S K+ K − Dalitz plot results. These results assume no CPV; for results allowing for CPV click here
Year | Experiment | Result | Comment | |||||
---|---|---|---|---|---|---|---|---|
2005/2007 | CLEO II.V |
|
|
|||||
2007 | Belle |
|
540 fb−1 near Υ(4S) resonance | |||||
2010 | BaBar |
|
468.5 fb−1 near Υ(4S) resonance | |||||
COMBOS average |
|
|
Plot of x average (click on for high resolution): Plot of y average (click on for high resolution):
Ψ(3770) → D0-D0 results, using correlations. These results are from CLEO-c's Standard fit, in which no external constraints are used in the fit. CLEO-c also quotes results from an Extended fit, in which external constraints for x, y, yCP, x'2, y' etc. (as measured by other experiments) are used in the fit. HFAG does not use the Extended results.
Year | Experiment | Parameter | Fit Result | Comment | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2012 | CLEO-c |
|
|
818 pb−1 at Ψ(3770) resonance |