Measurement of CP observables in B± → D(⁎)K± and B± → D(⁎)π± decays

Measurements of CP observables in B ± →D (⁎) K ± and B ± →D (⁎) π ± decays are presented, where D (⁎) indicates a neutral D or D ⁎ meson that is an admixture of D (⁎)0 and D¯ (⁎)0 states. Decays of the D ⁎ meson to the Dπ 0 and Dγ final states are partially reconstructed without inclusion of the neutral pion or photon, resulting in distinctive shapes in the B candidate invariant mass distribution. Decays of the D meson are fully reconstructed in the K ± π ∓ , K + K − and π + π − final states. The analysis uses a sample of charged B mesons produced in pp collisions collected by the LHCb experiment, corresponding to an integrated luminosity of 2.0, 1.0 and 2.0 fb −1 taken at centre-of-mass energies of s=7, 8 and 13 TeV, respectively. The study of B ± →D ⁎ K ± and B ± →D ⁎ π ± decays using a partial reconstruction method is the first of its kind, while the measurement of B ± →DK ± and B ± →Dπ ± decays is an update of previous LHCb measurements. The B ± →DK ± results are the most precise to date

Novos registros na distribuição geográfica de anuros na floresta com araucária e considerações sobre suas vocalizações

Estudos envolvendo análises bioacústicas têm possibilitado a identificação de espécies pertencentes a grupos complexos, bem como a descrição e diferenciação de espécies crípticas. Recorrendo a esta ferramenta e com o objetivo de aumentar o conhecimento sobre a composição de espécies de anfíbios em áreas de Floresta com Araucária, foram amostradas 11 áreas nos estados do Paraná e Santa Catarina. Os resultados ampliaram significativamente o conhecimento da distribuição geográfica de oito espécies de anfíbios anuros: Ischnocnema henselii, Dendropsophus anceps, atualmente classificada como criticamente ameaçada no Estado do Paraná, D. nahdereri, Scinax granulatus, Trachycephalus dibernardoi, Pseudis cardosoi, Leptodactylus araucaria e L. nanus. Alguns destes registros representam correções em identificações anteriores: Ischnocnema henselii é uma espécie críptica e algumas populações até o momento eram confundidas no Paraná com I. guentheri; Trachycephalus dibernardoi era identificada como T. imitatrix e Leptodactylus nanus como L. marmoratus. A caracterização e descrição dos cantos destas espécies também são apresentadas.Studies involving bioacoustics analysis turned possible the identification of complex species groups, as well as the description and differentiation of cryptic species. In order to increase the knowledge on the species composition of amphibians in Araucaria Forests, we sampled eleven areas in the states of Paraná and Santa Catarina, which significantly increased the geographic distribution range of eight amphibian species: Ischnocnema henselii, Dendropsophus anceps, a currently classified as critically endangered in Paraná State, D. nahdereri, Scinax granulatus, Trachycephalus dibernardoi, Pseudis cardosoi, Leptodactylus araucaria and L. nanus. Some of the new records represent corrections of previous identifications for example: Ischnocnema henselii is a cryptic species with some populations in Paraná that have been previously mistaken to I. guentheri; Trachycephalus dibernardoi was mistaken for T. imitatrix and Leptodactylus nanus to L. marmoratus. We also characterize and describe the calls of all these species.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Estadual Paulista Programa de Pós-graduação em Biologia AnimalUniversidade Federal de Goiás (UFG) Departamento de Ecologia Laboratório de Comportamento Animal e HerpetologiaUniversidade Federal do Acre Centro Multidisciplinar Laboratório de HerpetologiaStaatliches Museum für Naturkunde StuttgartUniversidade Tecnológica Federal do ParanáUniversidade Estadual Paulista Departamento de Zoologia e BotânicaUniversidade Estadual Paulista Programa de Pós-graduação em Biologia AnimalUniversidade Estadual Paulista Departamento de Zoologia e Botânic

Updated determination of D0–D¯ 0 mixing and CP violation parameters with D0 → K+ π − decays

We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D0\u2192K+\u3c0- to D0\u2192K-\u3c0+ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0 fb-1 recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x\u20322=(3.9\ub12.7) 710-5, y\u2032=(5.28\ub10.52) 710-3, and RD=(3.454\ub10.031) 710-3. Without this assumption, the measurement is performed separately for D0 and D0 mesons, yielding a direct CP-violating asymmetry AD=(-0.1\ub19.1) 710-3, and magnitude of the ratio of mixing parameters 1.00<|q/p|<1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed

Study of the lineshape of the chi(c1) (3872) state

A study of the lineshape of the chi(c1) (3872) state is made using a data sample corresponding to an integrated luminosity of 3 fb(-1) collected in pp collisions at center-of-mass energies of 7 and 8 TeV with the LHCb detector. Candidate chi(c1)(3872) and psi(2S) mesons from b-hadron decays are selected in the J/psi pi(+)pi(-) decay mode. Describing the lineshape with a Breit-Wigner function, the mass splitting between the chi(c1 )(3872) and psi(2S) states, Delta m, and the width of the chi(c1 )(3872) state, Gamma(Bw), are determined to be (Delta m=185.598 +/- 0.067 +/- 0.068 Mev,)(Gamma BW=1.39 +/- 0.24 +/- 0.10 Mev,) where the first uncertainty is statistical and the second systematic. Using a Flatte-inspired model, the mode and full width at half maximum of the lineshape are determined to be (mode=3871.69+0.00+0.05 MeV.)(FWHM=0.22-0.04+0.13+0.07+0.11-0.06-0.13 MeV, ) An investigation of the analytic structure of the Flatte amplitude reveals a pole structure, which is compatible with a quasibound D-0(D) over bar*(0) state but a quasivirtual state is still allowed at the level of 2 standard deviations

Measurement of the CKM angle γγ in B±→DK±B^\pm\to D K^\pm and B±→Dπ±B^\pm \to D π^\pm decays with D→KS0h+h−D \to K_\mathrm S^0 h^+ h^-

A measurement of $CP$-violating observables is performed using the decays $B^\pm\to D K^\pm$ and $B^\pm\to D \pi^\pm$, where the $D$ meson is reconstructed in one of the self-conjugate three-body final states $K_{\mathrm S}\pi^+\pi^-$ and $K_{\mathrm S}K^+K^-$ (commonly denoted $K_{\mathrm S} h^+h^-$). The decays are analysed in bins of the $D$-decay phase space, leading to a measurement that is independent of the modelling of the $D$-decay amplitude. The observables are interpreted in terms of the CKM angle $\gamma$. Using a data sample corresponding to an integrated luminosity of $9\,\text{fb}^{-1}$ collected in proton-proton collisions at centre-of-mass energies of $7$, $8$, and $13\,\text{TeV}$ with the LHCb experiment, $\gamma$ is measured to be $\left(68.7^{+5.2}_{-5.1}\right)^\circ$. The hadronic parameters $r_B^{DK}$, $r_B^{D\pi}$, $\delta_B^{DK}$, and $\delta_B^{D\pi}$, which are the ratios and strong-phase differences of the suppressed and favoured $B^\pm$ decays, are also reported