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We compute the masses of the ground, orbitally, and radially excited states in response to recent observations of some new B and B s meson states at the LHCb (Aaij et al. in Eur Phys J C 81(7):601, 2021). We also calculate the electromagnetic transition widths, leptonic decay width, decay constant, and appropriate branching ratios. Hamiltonian includes relativistic corrections to the potential and kinetic energy terms in the form of O 1 m and O (p 10) . We use the Gaussian wave function to solve the screening potential. The constructed Regge trajectories using the estimated masses allow us to associate some recently observed states with the B and B s meson families. The findings of this study are in reasonable agreement with existing experimental and theoretical research. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic properties of solutions for the constrained minimization problems. d b p (p) : = inf { u ∈ H V s (R 2) : ∫ R 2 | u | 2 d x = 1 } I p , b p (u) , where s ∈ (1 2 , 1) , p ∈ (0 , 2 s) , b p > 0 and I p , b p (u) : = 1 2 ∫ R 2 | (- Δ) s 2 u | 2 + V (x) | u | 2 d x - b p p + 2 ∫ R 2 | u | p + 2 d x , u ∈ H V s (R 2). First, when lim p ↗ 2 s b p = b < b ∗ , the set of minimizers of d b p (p) is compact in a suitable space as p ↗ 2 s . In addition, when lim p ↗ 2 s b p = b ≥ b ∗ , by developing suitable trial functions for some fine energy estimates, we prove that all minimizers must blow up and give decay properties of minimizers. [ABSTRACT FROM AUTHOR]

This paper addresses the existence and uniqueness of mild solution for fractional Navier–Stokes equation in the homogeneous Besov spaces. The existence and uniqueness of the global mild solution with small initial data is established. The results on existence and uniqueness of the local mild solution for arbitrary initial data are also studied. Meanwhile, we obtain properties about the regularity and decay of mild solutions. These conclusions are mainly based on the fixed point theorems, the implicit function theorem on Banach spaces and the properties of Mittag–Leffler functions. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the mass spectra and decay properties of B , B s and B c mesons using the relativistic potential model with confining potential V q (r) = 1 2 (1 + γ 0) (a 2 r + V 0). The calculated mass spectra of B , B s and B c accord to the findings of the experiments and other theoretical forecasts. Using the same parameters, we calculate possible radiative decay widths of V (n s) → P (n s) γ and P (n s) → V (n s) γ , n = 1 , 2 , 3 and weak leptonic decay constants of B , B s and B c mesons. Our results, in most cases, generally agree with experimental and other theoretical predictions. Finally, we also investigate mixing parameters x q , y q and χ q for B q 0 − B ¯ q 0 (q ϵ d , s) mesons, where our calculated values reasonably agree with the experiment. [ABSTRACT FROM AUTHOR]

In this paper, we consider the Cauchy problem for a family of evolution-parabolic coupled systems, which are related to the classical thermoelastic plate equations containing non-local operators. By using diagonalization procedure and WKB analysis, we derive representation of solutions in the phase space. Then, sharp decay properties in a framework of $ L^p-L^q $ are investigated via these representations. Particularly, some thresholds for the regularity-loss type decay properties are found.

This work is concerned with the time-fractional doubly parabolic Keller-Segel system in ℝN (N ≽ 1), and we derive some refined results on the large time behavior of solutions which are presupposed to enjoy some uniform boundedness properties. Moreover, the well-posedness and the asymptotic stability of solutions in Marcinkiewicz spaces are studied. The results are achieved by means of an appropriate estimation of the system nonlinearities in the course of an analysis based on Duhamel-type representation formulae and the Kato-Fujita framework which consists in constructing a fixed-point argument by using a suitable time-dependent space. [ABSTRACT FROM AUTHOR]

Our effort is to assign the spin–parity of experimentally unknown excited charm-strange mesons such as D s 1 (2536) ± , D s 2 ∗ (2573) ± , D s 1 ∗ (2860) ± , D s 3 ∗ (2860) ± and D sJ (3040) ± within the phenomenological framework of color-Coulomb plus screened potential model. To see the relativistic effect in the quark–antiquark bound state, we introduce the first-order correction O 1 m in the potential energy term and expanding the kinetic energy term up to O (p 10) . The spin–spin, spin–orbit and the spin–tensor interaction terms are incorporated perturbatively to see splitting in mass spectra. The spectroscopy of radially and orbitally excited charm-strange mesons are allows to construct the Regge trajectories in (M 2 , J) and (M 2 , n r) planes. Moreover, the radiative transitions and the decay properties of this excited charm-strange mesons are also calculated. Our results are listed with other theoretical outcomes obtained from the various potential model as well as with the experimental observations where available. These phenomenological study of excited charm-strange mesons could provide valuable information on the future experimental search for the missing higher radial and orbital excitations. [ABSTRACT FROM AUTHOR]

Nuclear data are important for production and medical application of a radionuclide. This brief review concentrates on nuclear reaction cross-section data. The availability of standardized nuclear data for accelerator-based production of medical radionuclides is outlined. Some new directions in radionuclide applications, for example, theranostic approach, bimodal imaging, and radionuclide targeted therapy, are considered and the status of relevant nuclear data is discussed. The current trends in nuclear data research using accelerators are elaborated. The increasing significance of intermediate energy accelerators in production of therapeutic radionuclides is emphasized.

In this paper, we give log-convexity properties for solutions to discrete Schrödinger equations with different discrete versions of Gaussian decay at two different times. For free evolutions, we use complex analysis arguments to derive these properties, while in a perturbative setting we use a preliminar log-convexity statement in order to conclude our result. [ABSTRACT FROM AUTHOR]

We consider the time‐fractional Keller‐Segel system of order α∈(0,1). Interesting properties of solutions are highlighted, like regularity and large time behavior in Lebesgue spaces, which depend on the fractional exponent α. [ABSTRACT FROM AUTHOR]

We consider the KdV equation with an additional non-local perturbation term defined through the Hilbert transform, also known as the OST-equation. We prove that the solutions u (t , x) have a pointwise decay in spatial variable: | u (t , x) | ≲ 1 1 + | x | 2 , provided that the initial data has the same decaying and moreover we find the asymptotic profile of u (t , x) when | x | → + ∞. Next, we show that decay rate given above is optimal when the initial data is not a zero-mean function and in this case we derive an estimate from below 1 | x | 2 ≲ | u (t , x) | for | x | large enough. In the case when the initial datum is a zero-mean function, we prove that the decay rate above is improved to 1 1 + | x | 2 + ε for 0 < ε ≤ 1. Finally, we study the local-well posedness of the OST-equation in the framework of Lebesgue spaces. [ABSTRACT FROM AUTHOR]

In this work, we study the existence of asymptotically periodic solutions to a class of partial differential equations with memory. Based on the decay properties in the energy norm, we use a new method to show the existence of asymptotically periodic solutions. Some examples are given to illustrate our conclusions. [ABSTRACT FROM AUTHOR]

This paper addresses the existence and uniqueness of mild solutions to the Navier–Stokes equations with time fractional differential operator of order α ∈ ( 0 , 1 ) . Several interesting properties about the solution are also highlighted, like regularity and decay rate in Lebesgue spaces, which will depend on the fractional exponent α . Moreover, it is shown that the L p -exponent range, which the solution belongs to, is different from the range for the solution of the classical problem with α = 1 . [ABSTRACT FROM AUTHOR]

This paper is an invitation to Fourier analysis in the context of reduced twisted C*-crossed products associated with discrete unital twisted C*-dynamical systems. We discuss norm-convergence of Fourier series, multipliers and summation processes. Our study relies in an essential way on the (covariant and equivariant) representation theory of C $$^*$$ -dynamical systems on Hilbert C*-modules. It also yields some information on the ideal structure of reduced twisted C*-crossed products. [ABSTRACT FROM AUTHOR]

Abstract: We investigate global strong solution to a 3-dimensional parabolic–hyperbolic system arising from the Keller–Segel model. We establish the global well-posedness and asymptotic behavior in the energy functional setting. Precisely speaking, if the initial difference between cell density and its mean is small in , and the ratio of the initial gradient of the chemical concentration and the initial chemical concentration is also small in , then they remain to be small in for all time. Moreover, if the mean value of the initial cell density is smaller than some constant, then the cell density approaches its initial mean and the chemical concentration decays exponentially to zero as t goes to infinity. The proof relies on an application of Fourier analysis to a linearized parabolic–hyperbolic system and the smoothing effect of the cell density and the damping effect of the chemical concentration. [Copyright &y& Elsevier]

Abstract: In this paper, we study the decay rate in time to solutions toward a multiwave pattern of the Cauchy problem for the one-dimensional viscous conservation law where the far field states are prescribed. Especially, we deal with the case that the flux function is convex or concave but linearly degenerate on some interval. As the corresponding Riemann problem admits a Riemann solution which consists of rarefaction waves and contact discontinuity, it has already been proved by Matsumura–Yoshida that the solution to the Cauchy problem tends toward the multiwave pattern which consists of the rarefaction waves and the viscous contact wave as the time goes to infinity. We investigate that the decay rate in time is in the -norm and for any in the -norm if the initial perturbation from the corresponding asymptotics satisfies . Furthermore, if the perturbation satisfies , the decay rate in time is for any in the -norm and for any in the -norm. The proof is given by , -energy and time-weighted -energy methods and the properties of the interactions between the nonlinear waves. We also prove the same results of the decay properties by the similar arguments to the initial–boundary value problem on the half space. [Copyright &y& Elsevier]

Abstract: Er3+-doped alkaline earth titanium phosphate (RTP) glasses with molar composition of 24 (NaPO3)6 +30 KH2PO4 +25 TiO2 +20 RCl2 +1 Er2O3 were prepared by melt quenching technique. Judd–Ofelt intensity parameters (Ω 2,4,6) were determined from the experimental oscillator strengths (f exp) of absorption bands. From these parameters spontaneous emission probabilities (A R), luminescence branching ratios (β R) and radiative lifetimes (τ R) have been calculated. Visible and near infrared photoluminescence spectra has been recorded by exciting the samples at 380 and 970nm respectively. An intense broad emission band at 1.53μm was observed corresponding to 4I13/2 → 4I15/2 transition. McCumber theory has been applied to determine the emission cross-sections (σ e) of the 4I13/2 → 4I15/2 transition using the absorption cross-sections (σ a). The lifetimes of 4S3/2 level were measured for the glasses by exciting the samples at 540nm wavelength and the quantum efficiencies were also determined. [Copyright &y& Elsevier]

I give a simple proof that the correlation functions of many-fermion systems have a convergent functional Grassmann integral representation, and use this representation to show that the cumulants of fermionic quantum statistical mechanics satisfy ℓ1-clustering estimates. [ABSTRACT FROM AUTHOR]

The fluorescence decay from five energy states of Er3+ ions for 8.4 and 10.5 at% Er3+:YAG crystals as well as for 1 at% Er3+:YAlO3 crystals have been observed using the time-resolved laser-induced fluorescence method. A tunable OPO laser with 6 ns pulse duration was used to excite selectively the Er3+ ions and sequent fluorescence was monitored. The radiative lifetimes for corresponding levels have also been calculated using Judd–Ofelt theory. The nonradiative decay rate was estimated from the experimental and theoretical data. The results will be useful for investigating upconversion and lasing process. [Copyright &y& Elsevier]

An approximate analytical description for fundamental-mode fields of graded-index fibers is explicitly presented by use of the power-series expansion method, the maximum-value condition at the fiber axis, the decay properties of fundamental-mode fields at large distance from the fiber axis, and the approximate modal parameters U obtained from the Gaussian approximation. This analytical description is much more accurate than the Gaussian approximation and at the same time keep the simplicity of the latter. As two special examples, we present the approximate analytical formulas for the fundamental-mode fields of a step profile fiber and a Gaussian profile fiber, and we find that they are both highly accurate in the single-mode range by comparing them with the corresponding exact solutions [ABSTRACT FROM PUBLISHER]

Abstract: In most investigations the Roper resonance is sensed only very indirectly via complex partial wave analyses. We find indications for its excitation in the reaction, where some resonance-like structure is observed in the invariant mass spectrum at with a width of 150 MeV. The values fit very favorably to the most recent phase shift results as well as to the observations at BES. In near-threshold two-pion production the Roper excitation and its subsequent decay into is the only dominant process. There we find its decay into the channel as the dominating decay process — in favor of a monopole nature of the Roper excitation. [Copyright &y& Elsevier]