5,198 research outputs found
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
An 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
Measurement of the time-dependent CP asymmetry in B0 -> J/ψ KS0 decays
This Letter reports a measurement of the CP violation observables SJ/ψK0S and CJ/ψK0S in the decay channel B0→J/ψK0S performed with 1.0 fb−1 of pp collisions at s√=7 TeV collected by the LHCb experiment. The fit to the data yields SJ/ψK0S=0.73±0.07(stat)±0.04(syst) and CJ/ψK0S=0.03±0.09(stat)±0.01(syst). Both values are consistent with the current world averages and within
expectations from the Standard Model
Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays
Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found
A study of CP violation in B±→DK±B±→DK± and B±→Dπ±B±→Dπ± decays with D→KS0K±π∓ final states
A first study of CP violation in the decay modes B± → [K0S K ±π∓]Dh± and B± → [K0S K ∓π±]Dh±, where h labels a K or π meson and D labels a D0 or D0 meson, is performed. The analysis uses the LHCb data set collected in pp collisions, corresponding to an integrated luminosity of 3 fb−1. The analysis is sensitive to the CP-violating CKM phase γ through seven observables: one charge asymmetry in each of the four modes and three ratios of the charge-integrated yields. The results are consistent with measurements of γ using other decay modes
Measurement of the CP-violating phase phi(s) in (B)over-bar(s)(0) -> J / psi pi(+)pi(-) decays
The mixing-induced CP -violating phase ϕs in View the MathML source and View the MathML source decays is measured using the J/ψπ+π− final state in data, taken from 3 fb−1 of integrated luminosity, collected with the LHCb detector in 7 and 8 TeV centre-of-mass pp collisions at the LHC. A time-dependent flavour-tagged amplitude analysis, allowing for direct CP violation, yields a value for the phase ϕs=70±68±8 mrad. This result is consistent with the Standard Model expectation and previous measurements
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CP violation
In this talk the author briefly reviews the cosmological importance of CP violation and the status of calculations of baryogenisis in the context of the Standard Model. The author then turns to a discussion of Standard Model Predictions for CP violation in B decays, stressing the importance of multiple measurements to overconstrain the model parameters and thus search for indications of beyond-Standard-Model physics
Phenomenology of CP-even ALP
Axion or axion-like particle (ALP) has been usually considered as a CP-odd
Nambu-Goldstone boson (NGB) from the spontaneous breakdown of a global U(1)
symmetry. In this paper, we point out that the NGB behaves as a CP-even
particle coupled to the SM particles in a large class of simple (or perhaps the
simplest) renormalizable models. We provide a first study of the collider
phenomenology and cosmology of the CP-even ALP. In a natural parameter region,
the CP-even ALP can be produced from the Higgs boson decay in colliders. When
the mass is not very light, the signals will be Higgs exotic decays, Higgs
decay to displaced vertex , Higgs decay to displaced vertex + missing
energy. The signal can be discriminated from other models, e.g. hidden photon,
by measuring the decay length and the decay products of the light new particle.
In addition, when MeV, in which case the Higgs boson invisible
decay may be probed in the colliders, the CP-even ALP is a nice Dark matter
(DM) candidate. The DM can be probed by 21cm line measurement, the future
measurement of the Milky way mass halo function in the Vera Rubin Observatory,
as well as X- or -ray observations. The DM production mechanisms are
discussed.Comment: 35pages, 7 figures, 1 table, v2: typo corrected, references adde
The complete chloroplast genome sequence of Phyllostachys incarnata Wen, 1982
Phyllostachys incarnata Wen, 1982 is one of the important material and edible bamboo specie of high quality in China. We reported the complete chloroplast(cp) genome of P. incarnata in this study. The cp genome of P. incarnata (GenBank accession number: OL457160) was a typical tetrad structure with a full length of 139,689 bp, comprising a pair of inverted repeated (IR) regions (21,798 bp) separated by a large single-copy (LSC) region (83,221 bp) and a small single-copy (SSC) region (12,872 bp). And the cp genome contained 136 genes, including 90 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis based on 19 cp genomes suggested that P. incarnata was relatively close to P. glauca among the species analyzed
Bond strengths of orthodontic bracket after acid-etched, Er:YAG laser-irradiated and combined treatment on enamel surface
Swelling and shrinking kinetics of a lamellar gel phase
We investigate the swelling and shrinking of L lamellar gel phases composed of surfactant and fatty alcohol after contact with aqueous poly(ethyleneglycol) solutions. The height change Δh(t) is diffusionlike with a swelling coefficient S: Δh=S√t. On increasing polymer concentration, we observe sequentially slower swelling, absence of swelling, and finally shrinking of the lamellar phase. This behavior is summarized in a nonequilibrium diagram and the composition dependence of S quantitatively described by a generic model. We find a diffusion coefficient, the only free parameter, consistent with previous measurements
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