A
bstract
The Cabibbo-suppressed semileptonic decay
$$ {B}^{+}\to p\overline{p}{\mu}^{+}{\nu}_{\mu } $$
B
+
→
p
p
¯
μ
+
ν
μ
is observed for the first time using a sample of
pp
collisions ...corresponding to an integrated luminosity of 1.0, 2.0 and 1.7 fb
−
1
at centre-of-mass energies of 7, 8 and 13 TeV, respectively. The differential branching fraction is measured as a function of the
$$ p\overline{p} $$
p
p
¯
invariant mass using the decay mode
B
+
→ J/ψK
+
for normalisation. The total branching fraction is measured to be
$$ \mathrm{\mathcal{B}}\left({B}^{+}\to p\overline{p}{\mu}^{+}{\nu}_{\mu}\right)=\left({5.27}_{-0.24}^{+0.23}\pm 0.21\pm 0.15\right)\times {10}^{-6}, $$
ℬ
B
+
→
p
p
¯
μ
+
ν
μ
=
5.27
−
0.24
+
0.23
±
0.21
±
0.15
×
10
−
6
,
where the first uncertainty is statistical, the second systematic and the third is from the uncertainty on the branching fraction of the normalisation channel.
A
bstract
A measurement of the
$$ {\varXi}_{cc}^{++} $$
Ξ
cc
+
+
mass is performed using data collected by the LHCb experiment between 2016 and 2018 in
pp
collisions at a centre-of-mass energy of 13 ...TeV, corresponding to an integrated luminosity of 5
.
6 fb
−
1
. The
$$ {\varXi}_{cc}^{++} $$
Ξ
cc
+
+
candidates are reconstructed via the decay modes
$$ {\varXi}_{cc}^{++}\to {\varLambda}_c^{+}{K}^{-}{\pi}^{+}{\pi}^{+} $$
Ξ
cc
+
+
→
Λ
c
+
K
−
π
+
π
+
and
$$ {\varXi}_{cc}^{++}\to {\varXi}_c^{+}{\pi}^{+} $$
Ξ
cc
+
+
→
Ξ
c
+
π
+
. The result, 3621
.
55
±
0
.
23 (stat)
±
0
.
30 (syst) MeV/
c
2
, is the most precise measurement of the
$$ {\varXi}_{cc}^{++} $$
Ξ
cc
+
+
mass to date.
A
bstract
A measurement of the time-dependent CP-violating asymmetry in
$$ {B}_s^0\to \phi \phi $$
B
s
0
→
ϕϕ
decays is presented. Using a sample of proton-proton collision data corresponding to an ...integrated luminosity of 5
.
0 fb
−
1
collected by the LHCb experiment at centre-of-mass energies
$$ \sqrt{s} $$
s
= 7 TeV in 2011, 8 TeV in 2012 and 13 TeV in 2015 and 2016, a signal yield of around 9000
$$ {B}_s^0\to \phi \phi $$
B
s
0
→
ϕϕ
decays is obtained. The CP-violating phase
$$ {\phi}_s^{s\overline{s}s} $$
ϕ
s
s
s
¯
s
is measured to be
−
0
.
073 ± 0
.
115(stat) ± 0
.
027(syst) rad, under the assumption it is independent of the helicity of the
ϕϕ
decay. In addition, the CP-violating phases of the transverse polarisations under the assumption of CP conservation of the longitudinal phase are measured. The helicity-independent direct CP-violation parameter is also measured, and is found to be |λ| = 0
.
99 ± 0
.
05(stat) ± 0
.
01(syst). In addition,
T
-odd triple-product asymmetries are measured. The results obtained are consistent with the hypothesis of CP conservation in
$$ \overline{b}\to \overline{s}s\overline{s}s $$
b
¯
→
s
¯
s
s
¯
s
transitions. Finally, a limit on the branching fraction of the
B
0
→
ϕϕ
decay is determined to be
$$ \mathcal{B}\left({B}^0\to \phi \phi \right)<2.7\times {10}^{-8} $$
B
B
0
→
ϕϕ
<
2.7
×
10
−
8
at 90 % confidence level.
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