Strong Decay Research Articles

Can the new states around 2.2 GeV be identified as the ω(3D)?

Recently, the BESIII Collaboration reported that there exist two explicit enhancement structures near 2.25[Formula: see text]GeV, one has the mass of [Formula: see text][Formula: see text]MeV and the width of [Formula: see text][Formula: see text]MeV and another structure has the mass of [Formula: see text][Formula: see text]MeV and the width of [Formula: see text][Formula: see text]MeV when analyzing the cross section of subprocesses. Earlier, the BESIII Collaboration reported the existence of the [Formula: see text], with a mass of [Formula: see text][Formula: see text]MeV and width of [Formula: see text][Formula: see text]MeV. Based on these experimental results, we carried out a study. We present the comparison of the mass spectrum between theoretical and experimental masses and examine the two-body strong decays of these states within two different approaches to the [Formula: see text] model. We find that the newly discovered states are most likely to be an [Formula: see text] state. This discovery could be useful in establishing entire [Formula: see text] mesons.

Room Temperature Spin-to-Charge Conversion in Amorphous Topological Insulating Gd-Alloyed BixSe1-x/CoFeB Bilayers.

Disordered topological insulator (TI) films have gained intense interest by benefiting from both the TI's exotic transport properties and the advantage of mass production by sputtering. Here, we report on the clear evidence of spin-charge conversion (SCC) in amorphous Gd-alloyed BixSe1-x (BSG)/CoFeB bilayers fabricated by sputtering, which could be related to the amorphous TI surface states. Two methods have been employed to study SCC in BSG (tBSG = 6-16 nm)/CoFeB(5 nm) bilayers with different BSG thicknesses. First, spin pumping is used to generate a spin current in CoFeB and detect SCC by the inverse Edelstein effect (IEE). The maximum SCC efficiency (SCE) is measured to be as large as 0.035 nm (IEE length λIEE) in a 6 nm thick BSG sample, which shows a strong decay when tBSG increases due to the increase of BSG surface roughness. The second method is THz time-domain spectroscopy, which reveals a small tBSG dependence of SCE, validating the occurrence of a pure interface state-related SCC. Furthermore, our angle-resolved photoemission spectroscopy data show dispersive two-dimensional surface states that cross the bulk gap until the Fermi level, strengthening the possibility of SCC due to the amorphous TI states. Our studies provide a new experimental direction toward the search for topological systems in amorphous solids.

Singly charm baryons with higher-order 𝒪1m2 corrections in hCQM: Revisited

In this study, singly charm baryons [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] have been studied. The known hypercentral Constituent Quark Model (hCQM) has been subjected to an addition of second-order correction term to the mass in spin-dependent term. This has allowed to observe the expected spin-splitting in the correct order and modify the previous findings to a new level. All the other properties have been obtained ranging from magnetic moment to strong decay width along with the linearly observed Regge trajectories.

The seed-to-solution method for the Einstein constraints and the asymptotic localization problem

We establish the existence of a broad class of asymptotically Euclidean solutions to Einstein's constraint equations, whose asymptotic behavior at infinity is prescribed arbitrarily. The proposed seed-to-solution method encompasses vacuum as well as matter spaces, and relies on iterations based on the linearized Einstein operator and its dual. It generates a Riemannian manifold (with finitely many asymptotically Euclidean ends) from any seed data set consisting of(1) a Riemannian metric and a symmetric two-tensor and(2) a (density) field and a (momentum) vector field representing the matter content. We distinguish between tame or strongly tame seed data sets, depending whether the data provides a rough or an accurate asymptotic Ansatz at infinity. We encompass classes of metrics and matter fields with low decay (possibly with infinite ADM mass) or strong decay (with Schwarzschild behavior). Our analysis is motivated by Carlotto and Schoen's pioneering work on the localization problem for Einstein's vacuum equations. Dealing with metrics with low decay and, simultaneously, establishing estimates that include (and go beyond) harmonic decay require significantly new arguments which are developed in the present paper. We work in a weighted Lebesgue-Hölder framework adapted to the given seed data, and we analyze the nonlinear coupling between the Hamiltonian and momentum constraints. By establishing elliptic regularity estimates for the linearized Einstein operator and its dual, we uncover the novel notion of mass-momentum correctors which is related to the ADM mass-momentum of the manifold. We derive precise estimates for the difference between the seed data and the associate Einstein solution —a result that should be of interest for future numerical investigations. Furthermore, we introduce here and study the asymptotic localization problem in which we replace Carlotto-Schoen's exact localization requirement by an asymptotic condition at a super-harmonic rate. By applying our seed-to-solution method with a suitably constructed, parametrized family of seed data, we solve this problem by exhibiting mass-momentum correctors with harmonic decay.

Competition in Multi-Airport Regions: Measuring airport catchments through spatial interaction models

The paper makes use of a novel dataset of the surface access flows of passengers departing from the four main airports surrounding London to construct a spatial interaction model for the region. This model explains the spatial variability in the flows through four separate components being [1] spatial separation between the origin of the flow and the destination airport, [2] the demand characteristics at the origin, [3] the attractiveness of the service offered by the airport, and [4] the presence of intervening opportunities. A spatial econometric approach is taken in the modelling to account for the presence of spatial dependence in the data.The output of the model reveals a strong distance decay effect, where the level of interaction between origins and airports displays a negative spatial gradient. Each of the four airports dominate passenger flows in their immediate vicinity, with the market in the region being hotly contested in central London. All four components of the model are useful in explaining spatial variation in passenger flows, demonstrating the efficacy of this approach in considering how airports source their demand in a Multi-Airport Region. The performance of the model is superior when considering passenger surface access flows for scheduled flights, while the explanatory power is reduced for flows associated with chartered flights. Having verified the applicability of the model, it is possible for policy makers to utilise the approach to consider such issues of expanding, limiting or reducing capacity at existing airports in the region, establishing new airport facilities, and the effect of population growth on the geographic form of airport demand.

Quantum Light from Lossy Semiconductor Rydberg Excitons.

The emergence of photonic quantum correlations is typically associated with emitters strongly coupled to a photonic mode. Here, we show that semiconductor Rydberg excitons, which are only weakly coupled to a free-space light mode can produce strongly antibunched fields, i.e., quantum light. This effect is fueled by a micron-scale excitation blockade between Rydberg excitons inducing pair-wise polariton scattering events. Photons incident on an exciton resonance are scattered into blue- and red-detuned pairs, which enjoy relative protection from absorption and thus dominate the transmitted light. We demonstrate that this effect persists in the presence of additional phonon coupling, strong nonradiative decay, and across a wide range of experimental parameters. Our results pave the way for the observation of quantum statistics from weakly coupled semiconductor excitons.

A Proposal to the ‘12 vs. 32 Puzzle’

We reconsider the semileptonic decays of B→D1(′)lν¯l. The previous theoretical calculations predict a significantly smaller rate for the semileptonic decay of B to D1′(Jl=12) compared with that to the D1(Jl=32), which is not consistent with the current experimental data. This conflict is known as the so-called ‘12 vs. 32 puzzle’. In this work, we propose a simple scheme to fix this problem, where we suppose the strong eigenstates D1(′) that do not coincide with the eigenstate of the weak interaction, since no experimental results show that the weak and the strong interactions have to share the same eigenstates. Within the framework of this tentative scheme, meson B first weakly decays to the weak eigenstates Dα(β) and then the latter are detected as the D1(′) by the strong decay products D*π. We predict that there exist two new particles Dα(β) with JP=1+, which were not previously identified. The good performance of the new scheme in describing the experimental data may hint at new symmetry in the weak decays of Bq to 1+ heavy–light mesons. To test the scheme proposed here, we suggest an experiment to detect the difference in the invariant mass spectra of D1 that is reconstructed from the B weak decay and from the strong decay products.

Microfauna community assembly and cascading relationship with microflora in cropland ecosystems along a latitudinal gradient

Cropland ecosystems are environmentally more homogeneous than natural ecosystems due to anthropogenic management. However, it is unclear whether there is similar convergence in soil fauna diversity and community assembly in croplands with different latitudes. Therefore, the study on the latitudinal pattern and community assembly processes of soil microfauna across a transect spanning 3200 km of croplands was conducted. The results indicated that the β diversity of plant parasites, fungivores, and bacterivores showed a decreasing trend and that of omnivores-predators at higher levels followed a unimodal distribution along a latitudinal gradient. The dissimilarity of soil microfauna communities increased with geographical distance, which exhibited a strong distance decay pattern. The β diversity partitioning analysis suggested that species replacement had the greatest influence for all trophic groups, except for omnivores-predators that were driven by a combination of richness differences and species replacement. The stochastic processes shaping the microfauna assembly prevailed over deterministic processes. Ecological drift and homogenizing dispersal of the stochastic processes accounted for 50.4% and 37% of total variations respectively, and heterogeneous selection of the deterministic processes for 10%. Both soil and climatic factors had a direct impact on soil microflora and plant parasites, and indirect impact on bacterivores, fungivores, and omnivores-predators through mediating microflora communities. The partial least squares path modeling and co-occurrence analysis all showed that the soil microfauna assembly was inextricably linked to soil microflora and their network complexity exhibited a significant increasing trend along the latitudinal gradient. Further studies are needed to optimize the molecular database of soil microfauna and construct models for predicting their community distribution patterns.

Charge Migration in HCCI Cations Probed by Strong Field Ionization: Time-Dependent Configuration Interaction and Vibrational Wavepacket Simulations.

Strong field ionization of neutral iodoacetylene (HCCI) can produce a coherent superposition of the X and A cations and results in charge migration between the CC π orbital and the iodine π-type lone pair. This charge migration causes oscillations in the rate of strong field ionization of the cation to the dication that can be monitored using intense few-cycle probe pulses. The dynamics and strong field ionization of the coherent superposition the X and A states of HCCI+ have been modeled by time-dependent configuration interaction (TDCI) simulations. When the nuclei are allowed to move, the electronic wavefunctions need to be multiplied by vibrational wavefunctions. Nuclear motion has been modeled by vibrational packets moving on quadratic approximations to the potential energy surfaces for the X and A states of the cation. The overlap of the vibrational wavepackets decays in about 10-15 fs. Consequently, the oscillations in the strong field ionization decay on the same time scale. A revival of the vibrational overlap and in the oscillations of the strong field ionization is seen at 60-110 fs. TDCI simulations show that the decay and revival of the charge migration can be monitored by strong field ionization with intense 2- and 4-cycle linearly polarized 800 nm pulses. The revival is also seen with 7-cycle pulses.

The strong decay of higher vector Upsilon(11020) state in the framework of non-relativistic quark model

An analytical study of a source of Beauty mesons (B mesons) by the Strong decay of Upsilon(11020) is performed to obtain various modes of B mesons. The non-relativistic quark model framework is used to predict the masses of the bottomonium mesons. The strong decay of the Upsilon(11020) state is calculated utilizing Quark Pair Creation model. In addition, the branching ratio of the strong decay has been calculated for each decay width and using them to estimate the number of B-meson pairs for each strong decay width. The results show reasonable agreement with recent Particle Data Group data, in particular with the total strong decay width of Upsilon(11020). The Upsilon(11020) particle is expected to be a good candidate for the conventional Upsilon(6S) state and provides both types of strange and non-strange B mesons. We found new conclusions for the strong decay widths of the Upsilon(11020) in the relativistic phase space. The strong width of the B^{*}B^{*} channel is predicted to be the highest width by the ratio (cong 51%) concerning higher vector Upsilon(11020) State. In addition, the specific B_{s}B_{s}^{*} channel is expected to be the highest width relative to higher Upsilon resonances.

Analysis of the decay [formula omitted] with the light-cone QCD sum rules

In this work, we tentatively assign the Y(4500) as the [uc]A˜[uc‾]V+[uc]V[uc‾]A˜+[dc]A˜[dc‾]V+[dc]V[dc‾]A˜ tetraquark state with the quantum numbers JPC=1−−, and study the three-body strong decay Y(4500)→D⁎−D⁎0π+ with the light-cone QCD sum rules. It is the first time to use the light-cone QCD sum rules to calculate the four-hadron coupling constants, the approach can be extended to study other three-body strong decays directly and diagnose the X, Y and Z states.

Strong decay properties of single heavy baryons ΛQ, ΣQ and ΩQ

Motivated by recent progresses in experiments in searching for the [Formula: see text] baryons, we systematically analyze the strong decay behaviors of single heavy baryons [Formula: see text], [Formula: see text] and [Formula: see text]. The two-body strong decay properties of [Formula: see text]-wave, [Formula: see text]-wave and some [Formula: see text]-wave states are studied with the [Formula: see text] model. The results support assigning the recently observed [Formula: see text] and [Formula: see text] as the 2S([Formula: see text]) and 1D([Formula: see text]) states, respectively. In addition, the quantum numbers of many other experimentally observed baryons are also suggested according to their strong decays. Finally, some baryons which have good potentials to be observed in experiments are predicted and the possible decay channels for searching for these predicted states are also suggested.

Radiative production and decays of the exotic [formula omitted] and its siblings

We study the production of the light JPC=1−+ hybrid isoscalars η1′(1855) and the yet undiscovered η1(1660) as intermediate states in the radiative decays of the charmonium (J/ψ) to two conventional mesons using a flavor symmetric Lagrangian. For this purpose, we use the J/ψ→γη1′(1855)→γηη′ process as the reference. We find that some of the decay channels have branching ratios similar to or larger than that of the γηη′ channel and are sensitive to the mixing between the hybrid isoscalars. We propose that relatively stable γηf1(1285) channel be explored for the presence of the light hybrid isoscalar η1hyb(1660). We also exploit the strong decay channels containing at least one vector meson to study the radiative decays of the whole hybrid nonet {π1(1600),K1hyb(1750),η1hyb(1660),η1′(1855)}. We find that the hybrids cannot radiatively decay into the I=0 pseudoscalars. Furthermore, the vector decay channels ((ρ/ω/ϕ)γ) of the hybrid isoscalars are sensitive to the strangeness content of the hybrids. We also provide estimates for the branching fractions for the radiative production and partial widths for the radiative decays of the hybrids.

Mass spectrum and decays of the first radial excitation axial vector meson nonet

In this work, the mass spectrum of the first radial excitation axial vector meson nonet is considered in the framework of the nonrelativistic constituent quark model and Regge phenomenology. After that, we investigate the strong decay characteristics of these states within the [Formula: see text] model. The results are compared to values from other phenomenological models, and they may be beneficial in the prospective search for [Formula: see text] meson nonets.

Decay properties of as a conventional meson* *Supported in part by the National Natural Science Foundation of China (12075073, 11865001); the Natural Science Foundation of Hebei Province, China (A2021201009); and Post-graduate's Innovation Fund Project of Hebei University (HBU2022BS002)

Taking as a conventional meson, we calculate its dominant strong and electromagnetic decays in the framework of the Bethe-Salpeter method. Our results are keV and keV. The contributions of the different partial waves from the initial and final state wave functions to the decay width are also calculated, and we find that the relativistic corrections in both decay processes are very large.

Decay resistance of Pterocarpus erinaceus Poir. and the antifungal properties of its extract

The processing residue of Pterocarpus erinaceus was used to obtain an ethanol-extract, whose anti-fungal properties and mode of action was investigated using multi-omics principles and gas chromatography-mass spectrometry. The results showed that the decay resistance of the heartwood of Pterocarpus erinaceus was in Grade I; it showed strong decay resistance. The effective concentration of 70% ethanol extract of the heartwood of Pterocarpus erinaceus was 13.8%. It showed high inhibition against Coriolus versicolor and Gloeophyllum trabeum, and the content of the extract was positively correlated with the diameter of the inhibition zone. Transcriptomics analysis showed there were 93 genes differentially expressed in Gloeophyllum trabeum. Among them, 42 genes were up-regulated and 51 genes were down-regulated. These genes were mainly related to oxidoreductase activity, integral components of the membrane, carbohydrate metabolism, lipid metabolism, and other related Gloeophyllum trabeum life activities. In total, 31 substances were separated and observed using GC-MS, and their peak areas accounted for 91.8% of the total peak area. Of these, 16 substances including ketones, esters, amines, alkanes, olefins and aromatic compounds showed a relatively high content. Ketones accounted for the most abundance at 29.1%. These compounds may represent the main active components of antifungal and decay resistance.

A direct numerical simulation study for confined non-isothermal jet impingement at moderate nozzle-to-plate distances: Capturing jet-to-ambient density effects

A direct numerical simulation (DNS) campaign is deployed for a series of confined downward oriented, non-isothermal turbulent impinging jet configurations. A baseline Reynolds number of 9960 is obtained through a precursor DNS pipe flow simulation (Reτ=505). Three jet temperature configurations (confinement height to nozzle diameter of three) enter a cylindrical domain that share ambient and impingement plate temperatures (298.15K). The range of jet temperatures are crafted such that the ratio of inlet to ambient density varies from unity to 0.52, showcasing the effect of density disparity on flow characteristics such as core collapse, radial mixing of momentum and energy, near-wall stagnation behavior, wall-jet profiles, and large-scale vortical structures. Surface quantities provided include mean radial heat flux and wall-shear stress profiles, and heat flux histograms at select radial stations. Results showcase increased radial normal stresses for higher temperature jets that support increased mixing, resulting in large-scale recirculation structures that are smaller, while retaining similar normalized radial wall profiles for shear stress, heat flux and pressure. Radial plots for wall shear stress and Nusselt number showcase strong radial decay as compared to previous configurations that share similar jet and ambient temperatures. For the 373.15 K case, a Gaussian-like histogram for heat fluxes at the impingement plate transitions to a log-normal profile as radial distances increase. In contrast, the 573.15 K configuration displays a bi-modal heat flux characteristic at the impingement plate, and in similar manner to the moderate temperature counterpart, transitions to a log-normal profile at larger radial distances.

Mass spectra of doubly heavy tetraquarks in diquark−antidiquark picture* *Supported by the National Natural Science Foundation of China under the No. 12165017.

Inspired by the recent observation of the first doubly charmed tetraquark T cc , we apply the linear Regge relation and mass scaling to study low-lying mass spectra of the doubly heavy tetraquark in a heavy-diquark−light-antidiquark picture. The measured data and other compatible estimates of ground-state masses of doubly heavy baryons are employed to evaluate masses of heavy diquark M QQ (Q = c, b) and the D/D s meson masses are used in mass scaling to determine the hyperfine mass splitting. Our mass computation indicates that all low-lying states of doubly heavy tetraquarks are unstable against strong decays to two heavy-light mesons, except for the ground states of nonstrange bb tetraquarks.

Strong decays of singly heavy baryons from a chiral effective theory of diquarks

A chiral effective theory of scalar and vector diquarks is formulated, which is based on $SU(3)_R\times SU(3)_L$ chiral symmetry and includes interactions between scalar and vector diquarks with one or two mesons. We find that the diquark interaction term with two mesons breaks the $U(1)_A$ and flavor $SU(3)$ symmetries. To determine the coupling constants of the interaction Lagrangians, we investigate one-pion emission decays of singly heavy baryons $Qqq$ ($Q=c, b$ and $q=u,d,s$), where baryons are regarded as diquark--heavy-quark two-body systems. Using this model, we present predictions of the unobserved decay widths of singly heavy baryons. We also study the change of masses and strong decay widths of singly heavy baryons under partial restoration of chiral symmetry.

Arrangement for the K2* meson family

Two observed structures with $M=1868\ifmmode\pm\else\textpm\fi{}{8}_{\ensuremath{-}57}^{+40}\text{ }\text{ }\mathrm{MeV}$ and $M=2073\ifmmode\pm\else\textpm\fi{}9{4}_{\ensuremath{-}240}^{+245}\text{ }\text{ }\mathrm{MeV}$ are the same states [${K}_{2}^{*}(1980)$] in Particle Data Group. In this paper, analysis of the mass spectrum and calculation of the strong decay for ${K}_{2}^{*}$ mesons support the assignment of ${2}^{3}{P}_{2}$ and ${1}^{3}{F}_{2}$ as the low- and high-mass states for ${K}_{2}^{*}(1980)$. This analysis reveals very important criteria for the assignment of the observed ${K}_{2}^{*}(1980)$, and experimental findings for this assignment are suggested. Additionally, some partial decay widths are predicted based on the high excitations of the ${K}_{2}^{*}$ family. This study is crucial for establishing and searching for the higher excitations in the future.