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Synthetic Aperture Radar (SAR) images are widely used in ship detection because of their all-weather and all-day imaging characteristics. However, there are two challenges for SAR ship detection. One is coherent speckle noise, causing ship confusion with similar objects and raising false alarms. The other is multi-scale ship detection, particularly in small ships, which suffers from insufficient accuracy. To address these challenges, this paper proposes a robust one-stage detector, S3MDet, for SAR ship detection with sequential three-way decisions (S3WDs) and multi-granularity. First, to effectively eliminate the interference of coherent speckle noise, a noise classification and denoising module (NCDM) S3WD-based is designed. This module can accurately classify the noise level of the image and only perform denoising on the images identified as noisy, avoiding unnecessary operations on noise-free images. Then, to solve the problem of multi-scale ship detection, a multi-granularity group attention module (MGAM) is designed to obtain a richer representation of multi-granularity features. This module adopts a multi-granularity group convolution structure and channel-wise attention weights to efficiently extract ship features of different scales from SAR images. Extensive experiments on four SAR ship datasets, including SAR-Ship-Dataset, HRSID, SSDD, and LS-SSDD-v1.0, validate the robustness of S3MDet, demonstrating that it achieves state-of-the-art performance. [ABSTRACT FROM AUTHOR]

Viscoelasticity characterizes the most important mechanical behavior of elastomers. Understanding the viscoelasticity, especially finite strain viscoelasticity, of elastomers is the key for continuation of their dedicated use in industrial applications. In this work, we present a mechanistic and physics-based constitutive model to describe and design the finite strain viscoelastic behavior of elastomers. Mathematically, the viscoelasticity of elastomers has been decomposed into hyperelastic and viscous parts, which are attributed to the nonlinear deformation of the cross-linked polymer network and the diffusion of free chains, respectively. The hyperelastic deformation of a cross-linked polymer network is governed by the cross-linking density, the molecular weight of the polymer strands between cross-linkages, and the amount of entanglements between different chains, which we observe through large scale molecular dynamics (MD) simulations. Moreover, a recently developed non-affine network model ( Davidson and Goulbourne, 2013 ) is confirmed in the current work to be able to capture these key physical mechanisms using MD simulation. The energy dissipation during a loading and unloading process of elastomers is governed by the diffusion of free chains, which can be understood through their reptation dynamics. The viscous stress can be formulated using the classical tube model ( Doi and Edwards, 1986 ); however, it cannot be used to capture the energy dissipation during finite deformation. By considering the tube deformation during this process, as observed from the MD simulations, we propose a modified tube model to account for the finite deformation behavior of free chains. Combing the non-affine network model for hyperelasticity and modified tube model for viscosity, both understood by molecular simulations, we develop a mechanism-based constitutive model for finite strain viscoelasticity of elastomers. All the parameters in the proposed constitutive model have physical meanings, which are signatures of polymer chemistry, physics or dynamics. Therefore, parametric materials design concepts can be easily gleaned from the model, which is also demonstrated in this study. The finite strain viscoelasticity obtained from our simulations agrees qualitatively with experimental data on both un-vulcanized and vulcanized rubbers, which captures the effects of cross-linking density, the molecular weight of the polymer chain and the strain rate. [ABSTRACT FROM AUTHOR]

High-resolution satellite precipitation products, which can provide a reasonable depiction of the spatial extent of rainfall, have been increasingly used to model hydrological processes. In this study, we introduced important satellite rainfall data - Fengyun (FY) precipitation product, and evaluated the data through streamflow simulation using the Soil and Water Assessment Tool model in Huifa River basin, China. Three precipitation inputs were conducted to investigate the simulation performance of the FY precipitation product: (1) available rain gauges within the watershed; (2) pixel values of FY-2 precipitation products nearest to the geographic centers of the subbasins; and (3) mean values of FY-2 precipitation pixels within the subbasins. The results showed that good model performance (defined as: NSE > 0.75; Nash-Sutcliffe efficiency: NSE) was achieved for all precipitation inputs both in the calibration and validation period. Best streamflow simulation was obtained when the model was calibrated with the third precipitation input, with NSE 0.86 and 0.84, R² 0.86 and 0.86 in the calibration and validation period. This study reveals that the FY precipitation product is a significant data source in modeling hydrological processes. Moreover, it is reasonable to use the mean values of the satellite precipitation pixels within the subbasins. [ABSTRACT FROM AUTHOR]

In this paper, we show how to use low-fidelity operations to control the dynamics of quantum systems. Noisy operations usually drive a system to evolve into a mixed state and damage the coherence. Sometimes frequent noisy operations result in the coherent evolution of a subsystem, and the dynamics of the subsystem is controlled by tuning noisy operations. Based on this, we find that universal quantum computation can be carried out by low-fidelity (fidelity <90%) operations. [ABSTRACT FROM AUTHOR]

Within the QCD factorization approach, we calculate the branching fractions and CP asymmetry parameters of 12 B → K*0(1430)K(*) decay modes under the assumption that the scalar meson K*0(1430) is the first excited state or the lowest-lying ground state in the quark model. We find that the decay modes with the scalar meson emitted have large branching fractions due to the enhancement of the large chiral factor rK*0X. The branching fractions of decays with the vector meson emitted become much smaller owing to the smaller factor rx. Moreover, the annihilation-type diagram will induce large uncertainties because of the extra free parameters dealing with the end-point singularity. For the pure annihilation-type decays, our predictions are smaller than those from the perturbative QCD approach by 2-3 orders of magnitude. These results will be tested by the ongoing LHCb experiment, forthcoming Belle-II experiment and the proposing circular electron-positron collider. [ABSTRACT FROM AUTHOR]

We consider two toy models of open inflation and investigate their ability to give a suppression of scalar power on large scales while also satisfying observational constraints on the spatial curvature of the Universe. Qualitatively we find that both models are indeed capable of fulfilling these two requirements, but we also see that effects of the quantum tunneling must be carefully taken into account if we wish to make quantitative predictions. [ABSTRACT FROM AUTHOR]

We construct two spin models on lattices (both two and three dimensional) to study the capability of quantum computational power as a function of temperature and the system parameter. There exists a finite region in the phase diagram such that the thermal equilibrium states are capable of providing a universal fault-tolerant resource for measurement-based quantum computation. Moreover, in such a region the thermal resource states on the three-dimensional lattices can enable topological protection for quantum computation. The two models behave similarly in terms of quantum computational power. However, they have different properties in terms of the usual phase transitions. The first model has a first-order phase transition only at zero temperature whereas there is no transition at all in the second model. Interestingly, the transition in the quantum computational power does not coincide with the phase transition in the first model. [ABSTRACT FROM AUTHOR]

Within the perturbative QCD approach, we recalculate the branching ratio and polarization fractions of the pure annihilation decay B → ΦΦ in both the standard model and the family nonuniversal Z' model. We find that this decay is dominated by the longitudinal part, while the transverse parts are negligibly due to the absence of the (S -- P)(S + P)-type operator. In the standard model, the branching ratio is predicted as (4.4+0.8+0.3-0.6-0.5) x 10-8, which is larger than the previous predictions. With an additional Z' boson, the branching ratio can be enhanced by a factor of 2 or reduced one-half in the allowed parameter space. These results will be tested by the ongoing LHCb experiment and forthcoming Super-6 experiments. [ABSTRACT FROM AUTHOR]

The full-core-plus-correlation method (FCPC) is extended to calculate the energies and fine structures of 1s²nd and 1s²nf (n=5) states for the lithiumlike systems with high nuclear charge from Z = 41 to 50. In calculating energy, the higher-order relativistic contribution is estimated under a hydrogenic approximation. The nonrelativistic energies and wave functions are calculated by the Rayleigh-Ritz method. The mass polarization and the relativistic corrections including the kinetic energy correction, the Darwin term, the electron-electron contact term, and the orbit-orbit interaction are calculated perturbatively as the first-order correction. The quantum-electrodynamics contributions to the energy and to the fine-structure splitting are estimated by using the effective nuclear charge formula. The excited energies, the fine structures, and other relevant term energies are given and compared with the data available in the literature. [ABSTRACT FROM AUTHOR]

In this paper, we show that the quantum Zeno effect can occur for generalized quantum measurements or operations. As a consequence of frequently performing nonselective measurements (or trace-preserving completely positive maps), the evolution of a certain measurement-invariant state is governed by an effective Hamiltonian defined by the measurement (or map) and the free-evolution Hamiltonian. For selective measurements, the state may change randomly with time according to measurement outcomes, but some physical quantities (operators) still evolve according to the effective Hamiltonian. [ABSTRACT FROM AUTHOR]

We present a protocol for generating entanglement over long distances in a two-dimensional quantum network based on the surface-error-correction code. This protocol requires a fixed number of quantum memories at each node of the network and tolerates error rates of up to 1.67% in the quantum channels. If local operations are of an error rate of 10-3, error rates of about 1.27% in the quantum channels are tolerable. [ABSTRACT FROM AUTHOR]

Within the QCD factorization formalism, we study the possible impacts of the nonuniversal Z' model, which provides a flavor-changing neutral current at the tree level, on rare decays B → K*0 ( 1430) Π. Under two different scenarios, Scenerio-1 (SI) and Scenerio-2 (S2), for identifying the scalar meson K*0(1430), the branching ratios, CP asymmetries, and isospin asymmetries are calculated in both the standard model and the family nonuniversal Z' model. We find that the branching ratios and CP asymmetries are sensitive to weak annihilation. In the standard model, with ρA = 1 and φA ∈ [--30°, 30°], the branching ratios of S1 (S2) are smaller (larger) than the experimental data. Adding the contribution of the Z' boson in two different cases (Case I and Case II), for SI, the branching ratios are still far away from experiment. For S2, in Case II, the branching ratios become smaller and can accommodate the data; in Case I, although the center values are enhanced, they can also explain the data with large uncertainties. Similar conclusions are also reached for CP asymmetries. Our results indicate that S2 is more favored than SI, even after considering new physics effects. Moreover, if there exists a nonuniversal Z' boson, Case II is preferred. All results can be tested in the LHC-b experiment and forthcoming super-B factory. [ABSTRACT FROM AUTHOR]

We propose a protocol for the creation of photonic Greenberger-Horne-Zeilinger and linear cluster states emitted from a single atom—or ion—coupled to an optical cavity field. The method is based on laser pulses with different polarizations and exploits the atomic transition amplitudes to state-selectively achieve the desired transitions. The scheme lies within reach of current technology. [ABSTRACT FROM AUTHOR]

We suggest that the uncertain state fX(1500) observed by Belle and BABAR more than a decade ago, which has been viewed as a single scalar or a combination of several even spin resonances, is the vector ρ0(1450) reported recently by LHCb. Adopting the perturbative QCD approach, we determine the dikaon distribution amplitudes with the ρ0(1450) resonance from the LHCb data for the quasi-two-body decays B±→π±ρ0(1450)→π±K+K-. It is then shown that the B+→K+K+K- decay spectrum around the invariant mass M(K+K-)∼1.5  GeV measured by BABAR can be well described by the resonant contribution from ρ0(1450). The broad structure in the B+→K+KSKS spectrum around the invariant mass 1.5 GeV of a KSKS pair, which ρ0(1450) cannot decay into because of Bose-Einstein statistics, can be accounted for by a nonresonant S-wave contribution alone. The branching fractions and/or the direct CP asymmetries of the B±→π±ρ0(1450)→π±K+K-, B+→K+ρ0(1450)→K+K+K- and B0→K0ρ0(1450)→K0K+K- modes are predicted, which can be tested at the ongoing LHCb and Belle-II experiments. We encourage experimental colleagues to scrutinize our postulation by analyzing relevant data with higher precision. [ABSTRACT FROM AUTHOR]

Novelty detection is the machine learning task to recognize data, which belong to an unknown pattern. Complementary to supervised learning, it allows us to analyze data model-independently. We demonstrate the potential role of novelty detection in collider physics, using autoencoder-based deep neural network. Explicitly, we develop a set of density-based novelty evaluators, which are sensitive to the clustering of unknown-pattern testing data or new-physics signal events, for the design of detection algorithms. We also explore the influence of the known-pattern data fluctuations, arising from nonsignal regions, on detection sensitivity. Strategies to address it are proposed. The algorithms are applied to detecting fermionic ditop partner and resonant ditop productions at LHC, and exotic Higgs decays of two specific modes at a future e+e- collider. With parton-level analysis, we conclude that potentially the new-physics benchmarks can be recognized with high efficiency. [ABSTRACT FROM AUTHOR]

The tthh production at colliders contains rich information on the nature of the Higgs boson. In this article, we systematically studied its physics at the high-luminosity Large Hadron Collider (HL-LHC), using exclusive channels with multiple (≥5) b-jets and one lepton (5b1ℓ), multiple (≥5) b-jets and opposite-sign dilepton (5b2ℓ), same-sign dilepton (SS2ℓ), multiple leptons (multi-ℓ), and ditau resonance (ττ). The scenarios analyzed include: (1) the tthh production in Standard Model; (2) the tthh production mediated by anomalous cubic Higgs self-coupling and tthh contact interaction; (3) heavy Higgs (H) production with ttH→tthh; and (4) pair production of fermionic top partners (T) with TT→tthh. To address the complication of event topologies and the mess of combinatorial backgrounds, a tool of boosted-decision-tree was applied in the analyses. The 5b1ℓ and SS2ℓ analyses define the two most promising channels. For the nonresonant tthh production, a combination of these exclusive analyses allows for its measurement in the SM with a statistical significance ∼0.9σ (with S/B>1%), and may partially break the sensitivity degeneracy with respect to a varying cubic Higgs self-coupling, a difficulty usually thought to exist in gluon fusion di-Higgs analysis at HL-LHC. These sensitivities were also projected to future hadron colliders at 27 TeV and 100 TeV. For the resonant tthh productions, the heavy Higgs boson in type II two-Higgs-doublet-model could be efficiently searched for between the mass thresholds 2mh

Recent experimental results of R(D(*)) deviate from the standard model (SM) by 3.1σ, suggesting a new physics (NP) that affects the b→cτν̅τ transition. Motivated by this, we investigate the possible NP effects in the Λb→Λcτν̅τ decay. For this purpose, assuming the neutrinos are left-handed, we calculate in detail the helicity amplitudes of Λb→Λcℓν̅ℓ (ℓ=e-, μ-, and τ-) decays with all possible four-fermion operators. Within the latest results of Λb→Λc form factors from lattice QCD calculations, we study these decays in a model-independent manner. The differential and total branching fractions, the longitudinal polarizations of final leptons and hadrons, the forward-backward asymmetries in the lepton side, the convexity parameters, and the ratio R(Λc) are calculated. In SM, we obtain the ratio R(Λc)=0.33±0.01. Supposing that NP only affects the third generation fermions, we present the correlations among R(D), R(D∗), and R(Λc), as the Λb→Λcτν̅τ and B→D(*)τν̅τ are all induced by b→cℓν̅ℓ. We perform a minimum χ² fit of the Wilson coefficient of each operator to the latest experimental data of different observables, including the ratios R(D(*)) and R(J/ψ) and the τ polarization Pτ(D∗). It is found that the left-handed scalar operator OSL affects the branching fraction remarkably, and the ratio R(Λc) can be enhanced by 30%. For other operators, the ratio amounts to 0.38±0.02, which is larger than prediction of SM by 20%. Using the fitted values of the Wilson coefficients of the single NP operators, we also give a prognosis for the physical observables of Λb→Λcτν̅τ, including the ratio R(Λc), forward-backward asymmetry, and other polarized observables as well as the differential branching fraction. Furthermore, we also study the effects of three typical NP models on the ratio and the differential branching fraction of Λb→Λcτν̅τ. We hope our results can be tested in the current LHCb experiment and the future high energy experiments. [ABSTRACT FROM AUTHOR]

In this work, we perform a combined analysis of the R(D), R(D*), and R(J/ψ) anomalies in a model-independent manner based on the general framework of the four-fermion effective field theory, paying special attention to the use of the hadronic form factors. For the B→D(D*) transition form factors, we use the heavy quark field theory parametrization which includes the higher-order corrections of ϱ(αs,ΛQCD/mb,c) and was determined recently from a fit to lattice QCD and light-cone sum rule results in complementary kinematical regions of the momentum transfer. For the Bc→J/ψ(ηc) transitions, we use the form factors calculated in the covariant light-front quark model, which are found to be well consistent with the preliminary lattice results. With this particular treatment of hadronic matrix elements, in our analysis the two classes of vector operators are shown to be the most favored single new physics (NP) operators by the current experimental constraints within 2σ and the LEP1 data on Br(Bc→τν) as well as the minimum χ2 fit, while the tensor operator is also allowed but severely constrained, and the scalar ones are excluded. Using the favored ranges and fitted values of the Wilson coefficients of the single NP operators, we also give a prognosis for the physical observables, such as the ratios of decay rates (R(D(D*)), R(J/ψ(ηc))) and other polarized observables as well as the q² distributions. [ABSTRACT FROM AUTHOR]

Within the framework of the perturbative QCD approach based on kT factorization, we study 40 Bc→DS decay modes in the leading order and leading power, where "S" stands for the light scalar meson. Under two different scenarios (S1 and S2) for the description of scalar mesons, we explore the branching fractions and related CP asymmetries. As a heavy meson consisting of two heavy quarks with different flavor, the light-cone distribution amplitude of the Bc meson has not been well defined, and therefore the δ function is adopted. We find that the contributions of emission diagrams are suppressed by the vector decay constants and Cabibbo-Kobayashi-Maskawa elements, and the contributions of annihilation are dominant. After the calculation, we also find that some branching fractions are in the range [10-5,10-4], which could be measured at the current LHCb experiment, and other decays with smaller branching fractions will be tested at high-energy colliders in the future. Furthermore, some decay modes have large CP asymmetries, but they are unmeasurable currently due to the small branching fractions. [ABSTRACT FROM AUTHOR]

We explore lepton-flavored electroweak baryogenesis, driven by CP-violation in leptonic Yukawa sector, using the τ-µ system in the two Higgs doublet model as an example. This setup generically yields, together with the flavor-changing decay h→τµ, a tree-level Jarlskog invariant that can drive dynamical generation of baryon asymmetry during a first-order electroweak phase transition and results in CP-violating effects in the decay h→ττ. We find that the observed baryon asymmetry can be generated in parameter space compatible with current experimental results for the decays h→τµ, h→ττ, and τ→µγ, as well as the present bound on the electric dipole moment of the electron. The baryon asymmetry generated is intrinsically correlated with the CP-violating decay h→ττ and the flavor-changing decay h→τµ, which thus may serve as "smoking guns" to test lepton-flavored electroweak baryogenesis. [ABSTRACT FROM AUTHOR]

We show that, in the presence of bulk masses, sterile neutrinos propagating in large extra dimensions (LED) can induce electron-neutrino appearance effects. This is in contrast to what happens in the standard LED scenario, and hence LED models with explicit bulk masses have the potential to address the MiniBooNE and LSND appearance results as well as the reactor and Gallium anomalies. A special feature in our scenario is that the mixing of the first Kaluza-Klein modes to active neutrinos can be suppressed, making the contribution of heavier sterile neutrinos to oscillations relatively more important. We study the implications of this neutrino mass generation mechanism for current and future neutrino oscillation experiments and show that the Short Baseline Neutrino Program at Fermilab will be able to efficiently probe such a scenario. In addition, this framework leads to massive Dirac neutrinos and thus precludes any signal in neutrinoless double beta decay experiments. [ABSTRACT FROM AUTHOR]

Continuous spontaneous localization (CSL) is a model that captures the effects of a class of extensions to quantum theory which are expected to result from quantum gravity and is such that wave-function collapse is a physical process. The rate of such a process could be very much lower than the upper bounds set by searches to date and yet still modify greatly the interpretation of quantum mechanics and solve the quantum measurement problem. Consequently experiments are sought to explore this. We describe an experiment that has the potential to extend sensitivity to CSL by many orders of magnitude. The method is to detect heating of the motion of charged macroscopic objects confined in a Paul trap. We discuss the detection and the chief noise sources. We find that CSL with standard parameters could be observed using a vibration-isolated ion trap of size 1 cm at ultralow pressure with optical interferometric detection. [ABSTRACT FROM AUTHOR]

Based on the assumption of two-quark structure for the light scalar mesons, within the perturbative QCD approach, we investigate the B→D(*)S(q=u,d,s) decays induced by the b→u transition, with S denoting a light scalar meson. Under two different scenarios, the branching ratios of 96 decay modes have been calculated, most of which are in the range 10-5 to 10-8. These results can be tested in the ongoing LHCb experiment and the forthcoming Belle-II experiment. The comparison between our predictions and the experimental data allows us to probe the inner structure of the scalar mesons. In the standard model, since all decays can only occur through tree operators, there are no CP asymmetries. We note that, due to the mass difference between charm quark and light quarks, the contribution from annihilation diagrams will be enhanced sizably, especially for these color-suppressed or pure-annihilation-type decay modes. We also find that the branching ratios of color-favored decays are sensitive to the different scenarios, so their measurement will help us differentiate the different scenarios. It is also found that the ratios between Br(B→D(*)σ) and Br(B→D(*)f0(980)) can be used to determine the mixing angle of σ and f0(980). [ABSTRACT FROM AUTHOR]

A numerical method based on Zabaydullin and Dubau's work [O. Zabaydullin and J. Dubau, J. Phys. B: At. Mol. Opt. Phys. 45, 115002 (2012)] has been developed to calculate the Cauchy principal value integral in scattering matrices and obtain photorecombination (PR) cross sections of low-lying resonances according to Davies and Seaton's theory [J. Phys. B 2, 757 (1969)], in which radiation damping is included. The Dirac R-matrix method is employed to secure the dipole matrix. Using this method, PR cross sections of C4+ for the KLL resonance are acquired, and compared with available experimental measurements and other close-coupling theoretical results. It is shown that our damped cross sections reproduce the experimental data and are in agreement with other theoretical results. Meanwhile, radiation damping can reduce the PR cross section for the 1s2p² ²P resonance (corresponding to two levels [(1s2p1/2)12p3/2]1/2 and [1s(2p²3/2)2]3/2 by three orders of magnitude. The unresolved and underestimated resonances 1s2p² 4P, 1s2s2p 4P, and 1s2p² ²P in the undamped Breit-Pauli R-matrix calculations [H. L. Zhang et al., J. Phys. B: At. Mol. Opt. Phys. 32, 1459 (1999)] are corrected. Besides, dielectronic recombination cross sections of C4+ for the KLL resonance are also presented for comparison using the relativistic configuration-interaction (RCI) method implemented in flexible atomic code (fac), which show radiation damping has pronounced influences on 1s2p² ²P due to much larger radiative rates compared with autoionization rates. Furthermore, radiative and autoionization rates for the intermediate states [(1s2p1/2)12p3/2]1/2 and [1s(2p²3/2)2]3/2 of the He-like ions with 6≤Z≤83 are calculated using fac, scaling laws of which are checked. Autoionization rates comply with the Z0eff scaling law for Z≥32, which is caused by relativistic effects. [ABSTRACT FROM AUTHOR]

The network paradigm for quantum computing involves interconnecting many modules to form a scalable machine. Typically it is assumed that the links between modules are prone to noise while operations within modules have a significantly higher fidelity. To optimize fault tolerance in such architectures we introduce a hierarchical generalization of the surface code: a small "patch" of the code exists within each module and constitutes a single effective qubit of the logic-level surface code. Errors primarily occur in a two-dimensional subspace, i.e., patch perimeters extruded over time, and the resulting noise threshold for intermodule links can exceed ~10% even in the absence of purification. Increasing the number of qubits within each module decreases the number of qubits necessary for encoding a logical qubit. But this advantage is relatively modest, and broadly speaking, a "fine-grained" network of small modules containing only about eight qubits is competitive in total qubit count versus a "course" network with modules containing many hundreds of qubits. [ABSTRACT FROM AUTHOR]

Presents information on the Luyuan Residential Area, a main housing project, in Changchun, China. Description of Luyuan; When the project began; Purpose of the project; Mention of Xu Mingliang, director of the Municipal Real Estate Adminstration; Features of the residential area.

We give a full investigation on the dynamics of power-law kinetic quintessence L(X, Φ) = V(Φ)(-X + X²) by considering the potential related parameter Γ(=VVn/ Vr²) as a function of another potential parameter λ(=Vt/kV3/2) ' which correspondingly extends the analysis of the dynamical system of our Universe from two dimensional to three dimensional. In addition to the critical points found in previous papers, we find a new de Sitter- like dominant attractor (cp6) and give its stable condition using the center manifold theorem. For the dark energy dominant solution (cp6 and cpl), it could be distinguished from canonical quintessence and tachyon models since the sound speed c²s = 0 or c² << 1. For the scaling solution (cp8), it is very interesting that the sound speed c²s = 1 /5, while it behaves as ordinary matter. We therefore point out that the power-law kinetic quintessence should have different signatures on the cold dark matter power spectrum and the cosmic microwave background both at early time, when this scalar field is an early dark energy with ΩΦ being non-negligible at high redshift, and at late time, when it drives the accelerating expansion. We still do not know whether there are any degeneracies of the impacts between these two epoches. They are expected to be investigated in future. [ABSTRACT FROM AUTHOR]

A chemical investigation of the EtOAc-soluble fraction from the ethanol extract of the medullae of Juncus effusus led to the isolation of three new 9,10-dihydrophenanthrenes, juncuenins E-G (1-3); two new phenanthrenes, dehydrojuncuenins D-E (4-5); one new feruloylated glycoside (6); and one known 9,10-dihydrophenanthrene (7). The structures of these compounds were determined by analyzing their spectroscopic data. Metabolites 1-4 and 7 were further evaluated for their in vitro cytotoxic activities against seven human cancer lines (A549, MCF-7, BEL-7402, HeLa, COLO205, BGC-823, and SK-OV-3). Among them, compound 1 exhibited weak cytotoxicity against MCF-7 and HeLa cell lines. Compound 7 showed moderate cytotoxicity against MCF-7 and HeLa cell lines, with IC50 values of 9.17 and 19.6 μM, respectively [ABSTRACT FROM AUTHOR]

With advances in quantum computing, new opportunities arise to tackle challenging calculations in quantum field theory. We show that trotterized time-evolution operators can be related by analytic continuation to the Euclidean transfer matrix on an anisotropic lattice. In turn, trotterization entails renormalization of the temporal and spatial lattice spacings. Based on the tools of Euclidean lattice field theory, we propose two schemes to determine Minkowski lattice spacings, using Euclidean data and thereby overcoming the demands on quantum resources for scale setting. In addition, we advocate using a fixed-anisotropy approach to the continuum to reduce both circuit depth and number of independent simulations. We demonstrate these methods with qiskit noiseless simulators for a 2+1D discrete non-Abelian D4 gauge theory with two spatial plaquettes. [ABSTRACT FROM AUTHOR]

Motivated by the measurements of the branching fractions of the quasi-two-body decays B0→K*0(f0(980)→)π+π- and B0→ρ0(f0(980)→)π+π-, we study the charmless B→V(f0(980)→)π+π- decays in the perturbative QCD approach. Supposing that f0(980) is a two-quark state and mixture of n̄n=(ūu+d̄d)/√2 and s̄s with the mixing angle θ, we calculate the branching fractions of these decays with the new introduced s-wave π+π--pair wave function. When the mixing angle θ lies in the range [135°,155°], the calculated branching fractions of the B0→K*0f0(980)→K*0π+π- and B0→ρ0f0(980)→ρ0π+π- decays are in agreement with the experimental data. The branching fractions of other decays could be measured in the current LHCb and Belle II experiments. Considering the isospin symmetry, we also estimate the branching fractions of the quasi-two-body decays B→Vf0(980)→Vπ0π0, which are half of the corresponding decays B→Vf0(980)→Vπ+π-. Moreover, the direct CP asymmetries of these decays are also calculated, and some of them can be tested in the current experiments. [ABSTRACT FROM AUTHOR]

In this paper we calculate the power corrections to the pion transition form factor within the framework of the perturbative QCD approach on the basis of k T factorization. The power suppressed contributions from higher-twist pion wave functions and the hadronic structure of photon are investigated. We find that there exists strong cancellation between the two kinds of contributions; thus, the total power corrections considered currently are very small, and the prediction of the leading power contribution with joint-resummation improved perturbative QCD approach is almost unchanged. This result confirms that the pion transition form factor is a good platform to constrain the nonperturbative parameters in pion wave functions. Moreover, our result can accommodate the anomalous data from BABAR, or agrees with results from Belle according to the choice of Gegenbauer moment in the pion wave function, and the more precise experimental data from Belle-II is expected. [ABSTRACT FROM AUTHOR]

Encouraged by the global agreement between theoretical predictions and experimental measurements for B→J/ψV decays, we extend that perturbative QCD formalism to B0d,s→J/ψf0(500)[f0(980)] decays at the presently known next-to-leading order in the quark-antiquark description of f0(500) and f0(980). With the angle ϕf≈25° of the f0(500)-f0(980) mixing in the quark-flavor basis, we find that the branching ratios of the B0d→J/ψf0(500)(→π+π-) and B0d,s→J/ψf0(980)(→π+π-) modes generally agree with the current data or the upper limits within uncertainties, except for the seemingly challenging B0s→J/ψf0(500)(→π+π-) one. Then, we further explore the relevant observables of the B0d,s→J/ψf0(500)[f0(980)] decays, which could provide further constraints on the mixing angle ϕf and/or SU(3) flavor symmetry breaking effects. As a byproduct, we predict BR(B0d→J/ψf0(980)(→K+K-))=5.8+3.1-2.9×10-7 and BR(B0s→J/ψf0(980)(→K+K-))=4.6+2.6-2.3×10-5. All theoretical predictions await the future examinations with high precision. [ABSTRACT FROM AUTHOR]

The lightest supersymmetric particle (LSP) is generally regarded as a Higgsino in focus point supersymmetry (SUSY). Under such a circumstance, it leads to a bileptino LSP when the minimal supersymmetric Standard Model (MSSM) is extended by the U(1)B-L gauge group within the framework of double focus point (DFP) supersymmetry. The bileptino is a copy of a Higgsino whose partner, the bilepton, is used to break U(1)B-L gauge symmetry spontaneously. Such a scenario, however, is not favored by direct detection since it leads to an unacceptable spin-independent cross section when one requires a correct self-scattering cross section. We point out that is not necessarily the case even in the presence of light Z′. The right-handed sneutrino in this model acts as the LSP in most of the parameter space for nonvanishing soft trilinear coupling Tη. It is thus consistent with the requirement of DFP SUSY without involving any direct detection issue. The corrected relic abundance could be achieved via a sneutrino annihilating into a pair of bileptons, which also serve as a light mediator in self-interacting dark matter (SIDM). Moreover, the stringent constraint that comes from cosmic microwave background anisotropies can be evaded by considering the retarded decay of right-handed neutrinos. We further stress the need for a large soft trilinear term Tη in order to generate a desirable self-scattering cross section σ/m˜νR with moderate Yukawa coupling Yη. The numerical calculation illustrates that SIDM is reliable in our model from the scales of a dwarf galaxy to a galaxy cluster. [ABSTRACT FROM AUTHOR]

Under the framework of soft-collinear effective theory, we analyze the charmless B → VV decays in a global way at leading power in 1 / m b and leading order in α s with V denoting a light vector meson. In the flavor SU(3) symmetry, decay amplitudes for the 28 decay modes are expressed in terms of eight nonperturbative parameters. We fit these eight nonperturbative parameters with 35 experimental results. Annihilation contributions are neglected due to power suppression in the m b → ∞ limit, so we include in the fit the nonperturbative charm penguins, which will play an important role in understanding the direct CP asymmetries. Charming penguins are also responsible for the large transverse polarizations of penguin-dominated and color-suppressed decays. With the best-fitted parameters, we calculate all possible physical observables of 28 decay modes, including branching fractions, direct C P asymmetries, and the complete set of polarization observables. Most of our results are compatible with the present experimental data when available, while others can be examined on the ongoing LHCb experiment and the forthcoming Belle II experiment. Moreover, the agreements and differences with results in QCD factorization and perturbative QCD approach are also discussed. A few observables are suggested to discriminate between these different approaches. [ABSTRACT FROM AUTHOR]

Within the factorization-assisted topological-amplitude approach, we study the two-body charmed B meson decays Bu,d,s → D(*)M, with M denoting a light pseudoscalar (or vector) meson. The meson decay constants and transition form factors are factorized out from the hadronic matrix element of topological diagrams. Therefore, the effect of SU(3) symmetry breaking is retained, which is different from the conventional topological diagram approach. The number of free nonperturbative parameters to be fitted from experimental data is also much less. Only four universal nonperturbative parameters XC,ϕC,XE and ϕE are introduced to describe the contribution of the color-suppressed tree and W-exchanged diagrams for all the decay channels. With the fitted parameters from 31 decay modes induced by b → c transition, we then predict the branching fractions of 120 decay modes induced by both b → c and b → u transitions. Our results are well consistent with the measured data or to be tested in the LHCb and Belle-II experiments in the future. Besides, the SU(3) symmetry breaking, isospin violation and CP asymmetry are also investigated. [ABSTRACT FROM AUTHOR]

We reexamine the branching fractions, CP asymmetries, and other observables in a large number of Bq → VV(q = u,d,s) decays in the perturbative QCD approach, where V denotes a light vector meson (ρ,K*,ω,ɸ). The essential difference between this work and earlier similar works is of parametric origin and in the estimates of the power corrections related to the ratio ri² = mVi²/mB²(i = 2,3) (mV and mB denote the masses of the vector and B meson, respectively). In particular, we use up-to-date distribution amplitudes for the final state mesons and keep the terms proportional to the ratio ri² in our calculations. Our updated calculations are in agreement with the experimental data, except for a limited number of decays which we discuss. We emphasize that the penguin annihilation and the hard-scattering emission contributions are essential to understanding the polarization anomaly, such as in the B → ɸK* and Bs → ɸɸ decay modes. We also compare our results with those obtained in the QCD factorization approach and comment on the similarities and differences, which can be used to discriminate between these approaches in future experiments. [ABSTRACT FROM AUTHOR]

Eight new 19-oxygenated ent-kaurane diterpenoids (1-8) were isolated from the aerial parts of Isodon pharicus. Their structures were determined by means of extensive spectroscopic techniques including interpretation of 1D and 2D NMR spectra. Selected compounds were evaluated for their cytotoxicity against NB4, A549, PC-3, MCF-7, and SH-SY5Y cell lines. [ABSTRACT FROM AUTHOR]

A phytochemical study of Isodon rubescens leaves led to the isolation of five new diterpenoids, isorubesins A–E (1–5), and fifteen known diterpenoids. The structures of these new compounds were elucidated by spectroscopic evidence. Most of the diterpenoids were tested for cytotoxicity against NB4, A549, SHSY5Y, PC3, and MCF7 human tumor cells. Some of them showed potent inhibitory activity. Compound 5 is the first reported atisane-type diterpenoid from this plant. [ABSTRACT FROM AUTHOR]

A phytochemical study of Isodon rubescens leaves led to the isolation of five new diterpenoids, isorubesins A-E (1-5), and fifteen known diterpenoids. The structures of these new compounds were elucidated by spectroscopic evidence. Most of the diterpenoids were tested for cytotoxicity against NB4, A549, SHSY5Y, PC3, and MCF7 human tumor cells. Some of them showed potent inhibitory activity. Compound 5 is the first reported atisane-type diterpenoid from this plant. [ABSTRACT FROM AUTHOR]

We investigate the B0d,s→f1f1 decays in the framework of perturbative QCD (PQCD) approach with a referenced value ϕf1∼24°. Here, f1 denotes the axial-vector mesons f1(1285) and f1(1420) with mixing angle ϕf1 in the quark-flavor basis. The observables such as branching ratios, direct CP violations, and polarization fractions of the B0s→f1f1 decays are predicted for the first time. We find that (i) the almost pure penguin modes B0s→f1f1 have large branching ratios in the order of 10-6∼10-5 due to the Cabibbo-Kobayashi-Maskawa enhancement and generally constructive interferences between the amplitudes of B0s→fnfs and B0s→fsfs with fn and fs being the quark-flavor states of f1 mesons. (ii) The observables receive important contributions from the weak annihilation diagrams in the PQCD approach. In particular, without the annihilation contributions, the B0s→f1(1420)f1(1420) branching ratio will decrease about 81% and its longitudinal polarization fraction will reduce around 43%. And (iii) the dependence of the B0d,s→f1f1 decay rates on ϕf1 exhibits some interesting line shapes, whose confirmations would be helpful to constrain the determination of ϕf1 inversely. All the PQCD predictions await for the (near) future examinations at Large Hadron Collider beauty and/or Belle-II experiments to further understand the properties of the axial-vector mesons and the perturbative dynamics released from the considered decay modes. [ABSTRACT FROM AUTHOR]

We consider the finite interactions of the generalized Proca theory including the sixth-order Lagrangian and derive the full linear perturbation equations of motion on the flat Friedmann-Lemaître-Robertson-Walker background in the presence of a matter perfect fluid. By construction, the propagating degrees of freedom (besides the matter perfect fluid) are two transverse vector perturbations, one longitudinal scalar, and two tensor polarizations. The Lagrangians associated with intrinsic vector modes neither affect the background equations of motion nor the second-order action of tensor perturbations, but they do give rise to nontrivial modifications to the no-ghost condition of vector perturbations and to the propagation speeds of vector and scalar perturbations. We derive the effective gravitational coupling Geff with matter density perturbations under a quasistatic approximation on scales deep inside the sound horizon. We find that the existence of intrinsic vector modes allows a possibility for reducing Geff. In fact, within the parameter space, Geff can be even smaller than the Newton gravitational constant G at the late cosmological epoch, with a peculiar phantom dark energy equation of state (without ghosts). The modifications to the slip parameter η and the evolution of the growth rate fσ8 are discussed as well. Thus, dark energy models in the framework of generalized Proca theories can be observationally distinguished from the ΛCDM model according to both cosmic growth and expansion history. Furthermore, we study the evolution of vector perturbations and show that outside the vector sound horizon the perturbations are nearly frozen and start to decay with oscillations after the horizon entry. [ABSTRACT FROM AUTHOR]