122,246 research outputs found
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
Barbara Krauz-Mozer, Piotr Borowiec, Paweł Ścigaj, Kim jesteś politologu? Historia i stan dyscypliny w Polsce (K. B. Janowski)
No full textBarbara Krauz-Mozer, Piotr Borowiec, Paweł Ścigaj, Kim jesteś politologu? Historia i stan dyscypliny w Polsce (K. B. Janowski
Dose- and time-dependent effects of recombinant human bone morphogenetic protein-2 on the osteogenic and adipogenic potentials of alveolar bone-derived stromal cells
No full textPark J-C, Kim J.C, Kim B-K, Cho K-S, Im G-I, Kim B-S, Kim C-S. Dose- and time-dependent effects of recombinant human bone morphogenetic protein-2 on the osteogenic and adipogenic potentials of alveolar bone-derived stromal cells. J Periodont Res 2012; 47: 645654. (C) 2012 John Wiley & Sons A/S Background and Objective: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a well-known growth factor that can induce robust bone formation, and recent studies have shown that rhBMP-2-induced osteogenesis is closely related to adipogenesis. The aim of the present study was to determine the dose- and time-dependent effects of rhBMP-2 on the osteogenic and adipogenic differentiation of human alveolar bone-derived stromal cells (hABCs) in vivo and in vitro. Material and Methods: hABCs were isolated and cultured, and then transplanted using a carrier treated either with or without rhBMP-2 (100 mu g/mL) into an ectopic subcutaneous mouse model. Comprehensive histologic and histometric analyses were performed after an 8-wk healing period. To further understand the dose-dependent (0, 10, 50, 200, 500 and 1000 ng/mL) and time-dependent (0, 3, 5, 7 and 14 d) effects of rhBMP-2 on osteogenic and adipogenic differentiation, in vitro osteogenic and adipogenic differentiation of hABCs were evaluated, and the expression of related mRNAs, including those for alkaline phosphatase, osteocalcin, bone sialoprotein, peroxisome-proliferator-activated receptor gamma-2 and lipoprotein lipase, were assessed using quantitative RT-PCR. Results: rhBMP-2 significantly promoted the osteogenic and adipogenic differentiation of hABCs in vivo, and gradually increased both the osteogenic and adipogenic potential in a dose- and time-dependent manner with minimal deviation in vitro. The expression of osteogenesis- and adipogenesis-associated mRNAs were concomitantly up-regulated by rhBMP-2. Conclusion: The findings of the present study showed that rhBMP-2 significantly enhanced the adipogenic as well as the osteogenic potential of hABCs in dose- and time-dependent manner. The control of adipogenic differentiation of hABCs should be considered when regenerating the alveolar bone using rhBMP-2.N
Measurement of the isospin asymmetry in B -> K(*) mu+mu- decays
No full textThe isospin asymmetries of B → K (∗) μ + μ − decays and the partial branching fractions of B 0 → K 0 μ + μ − and B + → K ∗+ μ + μ − are measured as a function of the di-muon mass squared q 2 using an integrated luminosity of 1.0 fb−1 collected with the LHCb detector. The B → Kμ + μ − isospin asymmetry integrated over q 2 is negative, deviating from zero with over 4 σ significance. The B → K ∗ μ + μ − decay measurements are consistent with the Standard Model prediction of negligible isospin asymmetry. The observation of the decay B 0 → K S μ + μ − is reported with 5.7 σ significance. Assuming that the branching fraction of B 0 → K 0 μ + μ − is twice that of B 0 → K S μ + μ −, the branching fractions of B 0 → K 0 μ + μ − and B → K ∗+ μ + μ − are found to be (0.31−0.06) × 10−6 and (1.16 ± 0.19) × 10−6, respectively
Observation of and
No full textInternational audienceWe report the study of B+→pΛ¯K+K- and B+→p¯ΛK+K+ decays using a 772×106 BB¯ pair data sample recorded on the ϒ(4S) resonance with the Belle detector at KEKB. The following branching fractions are measured: B(B+→pΛ¯K+K-)=(4.10-0.43+0.45±0.50)×10-6, B(B+→p¯ΛK+K+)=(3.70-0.37+0.39±0.44)×10-6, B(ηc→pΛ¯K-+c.c.)=(2.83-0.34+0.36±0.35)×10-3 and B(B+→pΛ¯ϕ)=( 7.95±2.09±0.77)×10-7, where c.c. denotes the corresponding charge-conjugation process. The intermediate resonance decays are excluded in the four-body decay measurements. We also find evidence for B(ηc→Λ(1520)Λ¯+c.c.)=(3.48±1.48±0.46)×10-3 and B(B+→Λ(1520)Λ¯K+)=( 2.23±0.63±0.25)×10-6. No significant signals are found for J/ψ→Λ(1520)Λ¯+c.c. and B+→Λ¯(1520)ΛK+; we set the 90% confidence level upper limits on their decay branching fractions as <1.80×10-3 and <2.08×10-6, respectively
Measurement of CP violating asymmetries in B^0 -> K^+K^- K^0_S decays with a time-dependent Dalitz approach
No full textWe report a measurement of violating asymmetries in decays with a time-dependent Dalitz approach. This analysis is based on a data sample of pairs accumulated at the resonance with the Belle detector at the KEKB asymmetric-energy collider. As the result of an unbinned maximum likelihood fit to the selected candidates, the mixing-induced and direct violation parameters, and are obtained for , and other decays. We find four solutions that describe the data. There are \{eqnarray*} \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (32.2 \pm 9.0 \pm 2.6 \pm 1.4)^{\circ}; \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (26.2 \pm 8.8 \pm 2.7 \pm 1.2)^{\circ};\\ \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (27.3 \pm 8.6 \pm 2.8 \pm 1.3)^{\circ}\; {\rm and}\\ \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (24.3 \pm 8.0 \pm 2.9 \pm 5.2)^{\circ}.{eqnarray*}\ The values for the violating phase in are similar but other properties of the Dalitz plot are quite different for the four solutions. These four solutions have consistent values for all three meson decay channels and none of them deviates significantly from the values measured in decays with the currently available statistics. In addition, we find no significant direct violation
Measurement of branching fractions for B → χc1(2)K (K*) at Belle
No full textWe have measured the branching fractions for the exclusive decay modes B→χc1(2)K(K*) using a 140 fb-1 data sample collected by the Belle detector at the KEKB asymmetric-energy e +e- collider. The measured branching fractions for B +→χc1K+, B0→χ c1K0, B0→χc1K* 0 and B+→χc1K*+ decay modes are (4.5±0.2±0.5)×10-4, (3.5±0.3±0.5)×10-4, (3.1±0.3±0.7) ×10-4 and (4.1±0.6±0.9)×10-4, respectively, where the first error is statistical and the second error is systematic. We do not observe statistically significant signals for the B→χc2K(K*) decay modes and set upper limits at the 90% confidence level. We also study the helicity distribution for B→χc1K* decay mode and show that the longitudinal polarization component is dominant. © 2006 Elsevier B.V. All rights reserved.LPH
First observation of the decay Bs0→K*0K*0
No full textThe first observation of the decay B0s→K∗0K∗0 is reported using 35 pb−1 of data collected by LHCb in proton–proton collisions at a centre-of-mass energy of 7 TeV. A total of 49.8±7.5 B0s→(K+π−)(K−π+) events are observed within ±50 MeV/c2 of the B0s mass and 746 MeV/c2 < mKπ < 1046 MeV/c2, mostly coming from a resonant B0s→K∗0K∗0 signal. The branching fraction and the CP-averaged K∗0 longitudinal polarization fraction are measured to be B(B0s→K∗0K∗0)=(2.81±0.46(stat.)±0.45(syst.)±0.34(fs/ fd))×10−5 and fL =0.31±0.12(stat.)±0.04(syst.)
Search for the suppressed decays B+→K+K+π− and B+→π+π+K−
No full text© 2016 The Author 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−1 collected 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 B(B+→K+K+π−)<1.1×10−8 and B(B+→π+π+K−)<4.6×10−8
- …
