A
bstract
The relative production rate of
and
B
0
mesons is determined with the hadronic decays
and
B
0
→
D
−
K
+
. The measurement uses data corresponding to 1.0 fb
−1
of
pp
collisions at a ...centre-of-mass energy of
TeV recorded in the forward region with the LHCb experiment. The ratio of production rates,
f
s
/f
d
, is measured to be 0
.
238 ± 0
.
004 ± 0
.
015 ± 0
.
021, where the first uncertainty is statistical, the second systematic, and the third theoretical. This is combined with a previous LHCb measurement to obtain
f
s
/f
d
= 0
.
256 ± 0
.
020. The dependence of
f
s
/f
d
on the transverse momentum and pseudorapidity of the
B
meson is determined using the decays
and
B
0
→
D
−
π
+
. There is evidence for a decrease with increasing transverse momentum, whereas the ratio remains constant as a function of pseudorapidity. In addition, the ratio of branching fractions of the decays
B
0
→
D
−
K
+
and
B
0
→
D
−
π
+
is measured to be 0
.
0822 ± 0
.
0011 (stat) ± 0
.
0025 (syst).
A search is made for the highly-suppressed B meson decays B+ → K+K+π– and B+ → π+π+K– using a data sample corresponding to an integrated luminosity of 3.0 fb–1collected by the LHCb experiment in ...proton–proton collisions at centre-of-mass energies of 7 and 8 TeV. No evidence is found for the decays, and upper limits at 90% confidence level are determined to be $\mathscr{B}$(B+→K+K+π–) < 1.1 × 10–8 and $\mathscr{B}$(B+→π+π+K–) < 4.6 × 10–8.
A
bstract
A measurement of the differential branching fraction of the decay
B
0
→
K
∗
(892)
0
μ
+
μ
−
is presented together with a determination of the S-wave fraction of the
K
+
π
−
system in the ...decay
B
0
→
K
+
π
−
μ
+
μ
−
. The analysis is based on
pp
-collision data corresponding to an integrated luminosity of 3 fb
−1
collected with the LHCb experiment. The measurements are made in bins of the invariant mass squared of the dimuon system,
q
2
. Precise theoretical predictions for the differential branching fraction of
B
0
→
K
∗
(892)
0
μ
+
μ
−
decays are available for the
q
2
region 1
.
1
< q
2
<
6
.
0 GeV
2
/c
4
. In this
q
2
region, for the
K
+
π
−
invariant mass range 796
< m
Kπ
<
996 MeV
/c
2
, the S-wave fraction of the
K
+
π
−
system in
B
0
→
K
+
π
−
μ
+
μ
−
decays is found to be
F
S
=
0.101
±
0.017
stat
±
0.009
syst
,
and the differential branching fraction of
B
0
→
K
∗
(892)
0
μ
+
μ
−
decays is determined to be
d
ℬ
/
d
q
2
=
0
.
392
−
0.019
+
0.020
stat
±
0.010
syst
±
0.027
norm
×
1
0
−
7
c
4
/
GeV
2
.
The differential branching fraction measurements presented are the most precise to date and are found to be in agreement with Standard Model predictions.
Here, measurements of the differential branching fraction and angular moments of the decay B0 → K+π- μ+ μ- in the K+π- invariant mass range 1330 < m(K+π-) < 1530 MeV/c2 are presented. Proton-proton ...collision data are used, corresponding to an integrated luminosity of 3 fb-1 collected by the LHCb experiment. Differential branching fraction measurements are reported in five bins of the invariant mass squared of the dimuon system, q2, between 0.1 and 8.0 GeV2/c4. For the first time, an angular analysis sensitive to the S-, P- and D-wave contributions of this rare decay is performed. The set of 40 normalised angular moments describing the decay is presented for the q2 range 1.1-6.0 GeV2/c4.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).The associated production of a Z boson or an off-shell photon gamma super( )*with a bottom quark in the forward region is ...studied using proton-proton collisions at a centre-of-mass energy of 7 TeV. The Z bosons are reconstructed in the Z/ gamma super( )* arrow right mu super( )+ mu super( )-final state from muons with a transverse momentum larger than 20 GeV, while two transverse momentum thresholds are considered for jets (10 GeV and 20 GeV). Both muons and jets are reconstructed in the pseudorapidity range 2.0 < eta < 4.5. The results are based on data corresponding to 1.0 fb super(-1) recorded in 2011 with the LHCb detector. The measurement of the Z+b-jet cross-section is normalized to the Z+jet cross-section. The measured cross-sections are ... ... for p sub(T)(jet) > 10 GeV, and ... ... for p sub(T)(jet) > 20 GeV. Figure not available: see fulltext.
A measurement of the effective Bs0→K+K− lifetime is presented using approximately 37 pb−1 of data collected by LHCb during 2010. This quantity can be used to put constraints on contributions from ...processes beyond the Standard Model in the Bs0 meson system and is determined by two complementary approaches asτKK=1.440±0.096 (stat)±0.008 (syst)±0.003 (model) ps.
A measurement of the differential branching fraction of the decay B 0 → K ∗(892)0 μ + μ − is presented together with a determination of the S-wave fraction of the K + π − system in the decay B 0 → K ...+π− μ + μ −. The analysis is based on pp-collision data corresponding to an integrated luminosity of 3 fb−1 collected with the LHCb experiment. The measurements are made in bins of the invariant mass squared of the dimuon system, q 2. Precise theoretical predictions for the differential branching fraction of B 0 → K ∗(892)0 μ + μ − decays are available for the q 2 region 1.1 < q 2 < 6.0 GeV2 /c 4. In this q 2 region, for the K +π− invariant mass range 796 < m Kπ < 996 MeV/c 2, the S-wave fraction of the K +π− system in B 0 → K +π− μ + μ − decays is found to be FS=0.101±0.017(stat)±0.009(syst), FS=0.101±0.017(stat)±0.009(syst), and the differential branching fraction of B 0 → K ∗(892)0 μ + μ − decays is determined to be dB/dq2=(0.392+0.020−0.019(stat)±0.010(syst)±0.027(norm))×10−7c4/GeV2. dB/dq2=(0.392−0.019+0.020(stat)±0.010(syst)±0.027(norm))×10−7c4/GeV2. The differential branching fraction measurements presented are the most precise to date and are found to be in agreement with Standard Model predictions.
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