3 research outputs found
Recommended from our members
Search for in decays
AbstractThe very rare
D
∗
(
2007
)
0
→
μ
+
μ
-
decay is searched for by analysing
B
-
→
π
-
μ
+
μ
-
decays. The analysis uses a sample of beauty mesons produced in proton–proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9
\,fb
-
1
. The signal signature corresponds to simultaneous peaks in the
μ
+
μ
-
and
π
-
μ
+
μ
-
invariant masses. No evidence for an excess of events over background is observed and an upper limit is set on the branching fraction of the decay at \mathcal{B}({{D} ^*} (2007)^0\!\rightarrow {\mu ^+\mu ^-} ) < 2.6\times 10^{-8}
B
(
D
∗
(
2007
)
0
→
μ
+
μ
-
)
<
2.6
×
10
-
8
at
90
%
confidence level. This is the first limit on the branching fraction of
D
∗
(
2007
)
0
→
μ
+
μ
-
decays and the most stringent limit on
D
∗
(
2007
)
0
decays to leptonic final states. The analysis is the first search for a rare charm-meson decay exploiting production via beauty decays.</jats:p
Recommended from our members
Search for decays and measurement of the branching fraction ratio
AbstractThe first search for nonresonant
B
c
+
→
π
+
μ
+
μ
-
decays is reported. The analysis uses proton–proton collision data collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9
fb
-
1
. No evidence for an excess of signal events over background is observed and an upper limit is set on the branching fraction ratio {\mathcal {B}} ({{B} _{c} ^+} \!\rightarrow {{\pi } ^+} {\mu ^+\mu ^-} )/{\mathcal {B}} ({{B} _{c} ^+} \!\rightarrow {{J \hspace{-1.66656pt}/\hspace{-1.111pt}\psi }} {{\pi } ^+} ) < 2.1\times 10^{-4}
B
(
B
c
+
→
π
+
μ
+
μ
-
)
/
B
(
B
c
+
→
J
/
ψ
π
+
)
<
2.1
×
10
-
4
at
90
%
confidence level. Additionally, an updated measurement of the ratio of the
B
c
+
→
ψ
(
2
S
)
π
+
and
B
c
+
→
J
/
ψ
π
+
branching fractions is reported. The ratio
B
(
B
c
+
→
ψ
(
2
S
)
π
+
)
/
B
(
B
c
+
→
J
/
ψ
π
+
)
is measured to be
0.254
±
0.018
±
0.003
±
0.005
, where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the leptonic
J
/
ψ
and
ψ
(
2
S
)
decays. This measurement is the most precise to date and is consistent with previous LHCb results.</jats:p
Search for decays and measurement of the branching fraction ratio
AbstractThe first search for nonresonant
B
c
+
→
π
+
μ
+
μ
-
decays is reported. The analysis uses proton–proton collision data collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9
fb
-
1
. No evidence for an excess of signal events over background is observed and an upper limit is set on the branching fraction ratio {\mathcal {B}} ({{B} _{c} ^+} \!\rightarrow {{\pi } ^+} {\mu ^+\mu ^-} )/{\mathcal {B}} ({{B} _{c} ^+} \!\rightarrow {{J \hspace{-1.66656pt}/\hspace{-1.111pt}\psi }} {{\pi } ^+} ) < 2.1\times 10^{-4}
B
(
B
c
+
→
π
+
μ
+
μ
-
)
/
B
(
B
c
+
→
J
/
ψ
π
+
)
<
2.1
×
10
-
4
at
90
%
confidence level. Additionally, an updated measurement of the ratio of the
B
c
+
→
ψ
(
2
S
)
π
+
and
B
c
+
→
J
/
ψ
π
+
branching fractions is reported. The ratio
B
(
B
c
+
→
ψ
(
2
S
)
π
+
)
/
B
(
B
c
+
→
J
/
ψ
π
+
)
is measured to be
0.254
±
0.018
±
0.003
±
0.005
, where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the leptonic
J
/
ψ
and
ψ
(
2
S
)
decays. This measurement is the most precise to date and is consistent with previous LHCb results.</jats:p