A
bstract
A search for
CP
violation in Cabibbo-suppressed
D
±
→
K
S
0
K
±
and
D
s
±
→
K
S
0
π
±
decays is performed using
pp
collision data, corresponding to an integrated luminosity of 3 fb, ...recorded by the LHCb experiment. The individual
CP
-violating asymmetries are measured to be
A
C
P
D
±
→
K
S
0
K
±
=
+
0.03
±
0.17
±
0.14
%
A
C
P
D
s
±
→
K
S
0
π
±
=
+
0.38
±
0.46
±
0.17
%
,
assuming that
CP
violation in the Cabibbo-favoured decays is negligible. A combination of the measured asymmetries for the four decay modes
D
(
s
)
±
→
K
S
0
K
±
and
D
(
s
)
±
→
K
S
0
π
±
gives the sum
A
C
P
D
±
→
K
S
0
K
±
+
A
C
P
D
s
±
→
K
S
0
π
±
=
+
0.41
±
0.49
±
0.26
%
.
In all cases, the first uncertainties are statistical and the second systematic. The results represent the most precise measurements of these asymmetries to date and show no evidence for
CP
violation.
A
bstract
An angular analysis of the decay
B
0
→
ϕK
*
(892)
0
is reported based on a
pp
collision data sample, corresponding to an integrated luminosity of 1
.
0 fb
−1
, collected at a centre-of-mass ...energy of
= 7 TeV with the LHCb detector. The P-wave amplitudes and phases are measured with a greater precision than by previous experiments, and confirm about equal amounts of longitudinal and transverse polarization. The S-wave
K
+
π
−
and
K
+
K
−
contributions are taken into account and found to be significant. A comparison of the
B
0
→
ϕK
*
(892)
0
and
results shows no evidence for direct
CP
violation in the rate asymmetry, in the triple-product asymmetries or in the polarization amplitudes and phases.
Search for the doubly charmed baryon Adinolfi, M.; Albrecht, J.; Anderlini, L. ...
The journal of high energy physics,
12/2013, Letnik:
2013, Številka:
12
Journal Article
Recenzirano
Odprti dostop
A
bstract
A search for the doubly charmed baryon
in the decay mode
is performed with a data sample, corresponding to an integrated luminosity of 0.65 fb
−1
, of
pp
collisions recorded at a ...centre-of-mass energy of 7 TeV. No significant signal is found in the mass range 3300-3800 MeV
/c
2
. Upper limits at the 95% confidence level on the ratio of the
production cross-section times branching fraction to that of the
,
R
, are given as a function of the
mass and lifetime. The largest upper limits range from
R
< 1.5 × 10
−
2 for a lifetime of 100 fs to
R <
3
.
9 × 10
−4
for a lifetime of 400 fs.
Using three- and four-body decays of \(D\) mesons produced in semileptonic \(b\)-hadron decays, precision measurements of \(D\) meson mass differences are made together with a measurement of the ...\(D^{0}\) mass. The measurements are based on a dataset corresponding to an integrated luminosity of \(1.0 fb^{-1}\) collected in \(pp\) collisions at 7\,TeV. Using the decay \(D^0 \rightarrow K^{+} K^{-} K^{-} \pi^{+}\), the \(D^0\) mass is measured to be \(M(D^0) &=& 1864.75 \pm 0.15 \,({\rm stat}) \pm 0.11 \,({\rm syst}) \, \textrm{MeV/c^2}\). The mass differences \(M(D^{+}) - M(D^{0}) = 4.76 \pm 0.12 \,({\rm stat}) \pm 0.07 \,({\rm syst}) \, \textrm{MeV/c^2}\) and \(M(D^{+}_s) - M(D^{+}) = 98.68 \pm 0.03 \,({\rm stat}) \pm 0.04 \,({\rm syst}) \, \textrm{MeV/c^2}\) are measured using the \(D^0 \rightarrow K^{+} K^{-} \pi^{+} \pi^{-}\) and \(D^{+}_{(s)} \rightarrow K^{+}K^{-} \pi^{+}\) modes.
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