Charmless decays B -> PP, PV, and effects of new strong and electroweak penguins in Topcolor-assisted Technicolor model

Based on the low energy effective Hamiltonian with generalized factorization, we calculate the new physics contributions to the branching ratios and CP-violating asymmetries of the two-body charmless hadronic decays $B \to PP, PV$ from the new strong and electroweak penguin diagrams in the TC2 model. The top-pion penguins dominate the new physics corrections, and both new gluonic and electroweak penguins contribute effectively to most decay modes. For tree-dominated decay modes $B \to \pi \pi, \rho \pi, etc,$ the new physics corrections are less than 10%. For decays $B \to K^{(*)} \pi$, $K^{(*)} \eta$, $etc$, the new physics enhancements can be rather large (from $- 70$ to $\sim 200$) and are insensitive to the variations of $N_c^{eff}$, $k^2$, $\eta$ and $m_{\tilde{\pi}}$ within the reasonable ranges. For decays $B^0 \to \phi \pi$, $\phi \eta^{(')}$, $K^* \bar{K}^0$ and $\rho^+ K^0$, $\delta {\cal B}$ is strongly $N_c^{eff}-$dependent: varying from -90% to $\sim 1680$ in the range of $N_c^{eff}=2-\infty$. The new physics corrections to the CP-violating asymmetries ${\cal A}_{CP}$ vary greatly for different B decay channels. For five measured CP asymmetries of $B \to K \pi, K \eta', \omega \pi$ decays, $\delta {\cal A}_{CP}$ is only about 20% and will be masked by large theoretical uncertainties. The new physics enhancements to interesting $B \to K \eta'$ decays are significant in size ($\sim 50$), insensitive to the variations of input parameters and hence lead to a plausible interpretation for the unexpectedly large $B \to K \eta'$ decay rates. The TC2 model predictions for branching ratios and CP-violating asymmteries of all fifty seven $B \to PP, PV$ decay modes are consistent with the available data within one or two standard deviations.Comment: Latex file, 56 pages with 11 ps and eps figures. to be published in Eur.Phys.J.

Different Regular Black Holes: Geodesic Structures of Test Particles

This paper investigates the metric of previously proposed regular black holes, calculates their effective potentials, and plots the curves of the effective potentials. By determining the conserved quantities, the dynamical equations for particles and photons near the black hole are derived. The analysis encompasses timelike and null geodesics in different spacetimes, including bound geodesics, unstable circular geodesics, stable circular geodesics, and escape geodesics. The findings are presented through figures and tables. Furthermore, the bound geodesics of the four regular black hole spacetimes are analyzed, examining the average distance of particle orbits from the center of the event horizon, the precession behavior of the perihelion, and the probability of particles appearing inside the outer event horizon during motion. Based on these analyses, a general formula is proposed, which yields the existing metrics when specific parameter values are chosen. The impact of parameter variations on the effective potential and geodesics is then computed using this new formula.Comment: 23 pages, 13 figure

Effects of Phi and σ∗\sigma^{*}-meson on properties of hyperon stars including Δ\Delta resonance

In this work, we study the properties of neutron stars using the linear Relativistic Mean-Field (RMF) theory and consider multiple degrees of freedom inside neutron stars, including hyperons and $\Delta$ resonances. We investigate different coupling parameters $x_{\sigma \Delta}$ between $\Delta$ resonances and nucleons and compare the differences between neutron stars with and without strange mesons $\sigma^*$ and $\phi$. These effects include particle number distributions, equations of state (EOS), mass-radius relations, and tidal deformabilities. To overcome the "hyperon puzzle," we employ the $\sigma-cut$ scheme to obtain neutron stars with masses up to $2M_{\odot}$. We find that strange mesons appear at around 3$\rho_0$ and reduce the critical density of baryons in the high-density region. With increasing coupling parameter $x_{\sigma \Delta}$, the $\Delta$ resonances suppress hyperons, leading to a shift of the critical density towards lower values. The early appearance of $\Delta$ resonances may play a crucial role in the stability of neutron stars. Strange mesons soften the EOS slightly, while $\Delta$ resonances predominantly soften the EOS in the low-density region. By calculating tidal deformabilities and comparing with astronomical observation GW170817, we find that the inclusion of $\Delta$ resonances decreases the radius of neutron stars.Comment: 10 pages, 9 figure

Functional Gradient Material of Ti-6Al-4V and γ-TiAl Fabricated by Electron Beam Selective Melting

Additive Manufacturing (AM) technologies are very promising in fabricating functionally graded materials. Electron Beam Selective Manufacturing (EBSM) is one widely used AM technology capable of fabricating a variety of materials especially titanium alloys. Previous studies on EBSM process were focused on the manufacturing of one single material. In this study, a novel EBSM process capable of building gradient structures with dual metal materials was developed. Ti6Al4V powders and Ti47Al2Cr2Nb powders were used to fabricate Ti3Al/TiAl and Ti6Al4V/Ti3Al dual metal structures. The chemical compositions, microstructure and micro-hardness of the dual material samples were investigated employing Optical Microscope (OM), Scanning Electronic Microscope (SEM), Electron Probe Micro-Analyzer (EPMA). Results showed that the thickness of the transition zone was about 300μm. The transition zone was free of cracks, and the chemical compositions exhibited a staircase-like change. The microstructure and chemical compositions in different regions were studied. Microhardness was affected by the microstructure. The microstructures turned out to be full lamellar at the TiAl region and basket-weave structure at the Ti3Al and Ti6Al4V region.Mechanical Engineerin

Kaon Meson Condensation and Δ\Delta resonance of Hyperonized Star with relativistic mean-field model

We study the equation of state of dense baryon matter within the relativistic mean-field model, and we include ${\Delta}$(1232) isobars into IUFSU model with hyperons and consider the possibility of kaon meson condensation. We find that it is necessary to consider the $\Delta$ resonance state inside the massive neutron star. The critical density of Kaon mesons and hyperons is shifted to a higher density region, in this respect an early appearance of $\Delta$ resonances is crucial to guarantee the stability of the branch of hyperonized star with the difference of the coupling parameter $x_{\sigma \Delta}$ constrained based on the QCD rules in nuclear matter. The $\Delta$ resonance produces a softer equation of state in the low density region, which makes the tidal deformability and radius consistent with the observation of GW170817. As the addition of new degrees of freedom will lead to a softening of the equation of state, the ${\sigma}$-cut scheme, which states the decrease of neutron star mass can be lowered if one assumes a limited decrease of the ${\sigma}$-meson strength at ${\rho_B}$($\rho_B > \rho_0$), finally we get a maximum mass neutron star with $\Delta$ resonance heavier than 2$M_{\odot}$.Comment: 10 pages, 9 figure

Appendix for Nonparametric Multivariate Probability Density Forecast in Smart Grids With Deep Learning

This paper proposes a nonparametric multivariate density forecast model based on deep learning. It not only offers the whole marginal distribution of each random variable in forecasting targets, but also reveals the future correlation between them. Differing from existing multivariate density forecast models, the proposed method requires no a priori hypotheses on the forecasted joint probability distribution of forecasting targets. In addition, based on the universal approximation capability of neural networks, the real joint cumulative distribution functions of forecasting targets are well-approximated by a special positive-weighted deep neural network in the proposed method. Numerical tests from different scenarios were implemented under a comprehensive verification framework for evaluation, including the very short-term forecast of the wind speed, wind power, and the day-ahead forecast of the aggregated electricity load. Testing results corroborate the superiority of the proposed method over current multivariate density forecast models considering the accordance with reality, prediction interval width, and correlations between different random variables