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<jats:title>Abstract</jats:title> <jats:p>Multinucleon transfer reactions near the Coulomb barrier have been investigated based on the improved dinuclear system (DNS) model, and the deexcitation process of primary fragments are described by statistical model GEMINI++. The production cross sections of $^{40,48}$Ca+$^{124}$Sn and $^{64}$Ni+$^{130}$Te based on the DNS model+GEMINI++ have been calculated and compared with the experimental data. The calculated results have reproduced the experimental data. The cross sections of fusion-evaporation reaction, fragmentation reaction and multinucleon transfer reaction in the $40 \leq Z \leq 60$ region are also given in this paper. The results show that in the $40 \leq Z \leq 60$ region, fusion-evaporation and fragmentation reactions have good results in the relatively proton-rich region, but in the extreme proton-deficient region, the MNT reaction is still promising to synthesize proton-rich nuclei.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Based on the current measurement of the neutron distribution radius ($R_n$) of $^{208}$Pb through the PREX-2 data, we re-visited the recently developed G3 and IOPB-I force parameters by fine-tuning some of the specific couplings within the relativistic mean-field (RMF) model. The $\omega$-$\rho$-mesons coupling $\Lambda_{\omega}$ and the $\rho$-meson coupling $g_{\rho}$ are constrained to the experimental neutron radius of $^{208}$Pb without compromising the bulk properties of finite nuclei and infinite nuclear matter observable. The modified parameter sets are applied to calculate the gross properties of finite nuclei such as binding energies, charge distributions, nuclear radii, pairing gaps, and single-particle energies. The root-mean-square deviations in binding energy and charge radius are estimated with respect to the available experimental data for 195 even-even nuclei, and the results compare favourably with the well-calibrated effective interactions of Skyrme, Gogny and other relativistic mean-field parametrizations. The pairing gap estimations for modified G3 and IOPB-I (i.e G3(M) and IOPB-I(M)) for Sn isotopes are also compared with the Hartree-Fock-Bogoliubov calculation with the Gogny (D1S) interaction. The isotopic shift and single-particle energy spacing are also calculated and compared with the experimental data for both original (O) and modified (M) versions of G3 and IOPB-I parameter sets. Subsequently, both the modified parameter sets are used to obtain the various infinite nuclear matter observables at saturation. In addition to these, the force parameters are adopted to calculate the properties of a high isospin asymmetry dense system such as neutron star matter and tested for the validation for the constraint from GW170817 binary neutron star merger events. The tuned forces are predicting relatively good results for finite and infinite nuclear matter systems and the current limitation on neutron radius from PREX-2. A systematic analysis using these two refitted parameter sets over the nuclear chart will be communicated shortly.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Excited states of $^{119}$Sn have been studied using an in-beam $\gamma$-ray spectroscopic technique following the incomplete fusion of $^{7}$Li on an $^{116}$Cd target at a beam energy of 42 MeV. A new bandlike structure is proposed to be arised from deformed two-particle-two-hole (2p-2h) proton excitations across the $Z$ = 50 closed shell based on the systematics of the odd-$A$ Sn isotopes and the configuration-fixed constrained triaxial relativistic mean-field calculations. This observation extends the boundaries of the deformed 2p-2h collective band to $A$ = 119 in the Sn isotopes.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Charmonia dissociation is an important probe of the QGP medium in heavy-ion collisions. The magnetic field produced in non-central collisions can affect the charmonia and their dissociation. We study the $c\bar{c}$ bound state in the magnetic field and at finite temperature using the Schrodinger equation. We find that below the dissociation temperature, both the magnetic field and momentum of charmonia affect the formation or dissociation of the bound state, forming a non-trivial structure.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We study the linear instability and the nonlinear dynamical evolution of the Reissner-Nordstr\"om (RN) black hole in the Einstein-Maxwell-scalar theory in asymptotic flat spacetime. We focus on the coupling function $f(\phi)=e^{-b\phi^2}$ which allows both the scalar-free RN solution and scalarized black hole solution. We first present the evolution of system parameters during dynamic scalarization. For parameter regions where spontaneous scalarization occurs, we find that the evolution of the scalar field at the horizon is dominated by the fundamental unstable mode from linear analysis at early times. At late times, the nonlinear evolution can be viewed as the perturbation of scalarized black holes.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Light mesons $(\sigma, \pi^0, \pi^\pm)$ are investigated in $\mu_B-T-eB$ and $\mu_I-T-eB$ spaces by using a two-flavor NJL model, and they are used to determine the chiral symmetry restoration and pion superfluid phase transition. In $\mu_B-T-eB$ space, during the chiral symmetry restoration process, the mass of pseudo-Goldstone mode $\pi^0$ keeps increasing, associated with the sudden jumps. At the critical end point, $\pi^0$ meson has a very sharp but continuous mass increase, together with a sudden mass jump at the Mott transition. In the first order chiral phase transition region nearby, we observe twice $\pi^0$ mass jumps, induced by the Mott transition and quark mass jump, respectively. The mass of Higgs mode $\sigma$ first decreases and then increases with the chiral symmetry restoration, and it shows a jump only at the first order chiral phase transition. We plot the chiral phase diagram in terms of the change of quark mass, Mott transition of pseudo-Goldstone mode $\pi^0$ and minimum mass of Higgs mode $\sigma$. The $\pi^0$ and $\sigma$ mass jumps will be helpful to the experimental search for chiral phase diagram and the critical end point. In $\mu_I-T$ plane, the competition between pion superfluid phase transition and chiral symmetry restoration under magnetic fields is studied in terms of the (pseudo-)Goldstone mode $\pi^+$ and $\pi^0$. The $\pi^+$ meson displays several mass jumps in the chiral crossover region. At the critical end point, $\pi^+$ also shows very sharp but continuous mass change, together with a mass jump at the Mott transition. The isospin symmetry is strict, and the pion superfluid phase transition is uniquely determined by the massless Goldstone mode $\pi^+$. The separation of the chiral restoration and pion superfluid phase boundaries is enhanced by the external magnetic field.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The influence of the isospin-breaking $\pi^0\!\!-\!\eta\!-\!\eta'$ mixing effect on the $CP$-asymmetries of $B\to K\pi$ processes is examined for the first time. It is found that this mixing effect brings a large uncertainty both to the $CP$-asymmetry sum rule of $B\to K\pi$ processes and the $CP$-asymmetry difference of the $B^+\to K^+\pi^0$ and $B^0\to K^+\pi^-$, potentially obscuring the significance of the $K\pi$-puzzle. %This uncertainty can be so large that it is even possible to explain the $K\pi$-puzzle by the $\pi^0\!\!-\!\eta\!-\!\eta'$ mixing effect alone. Since the correction caused by the $\pi^0\!\!-\!\eta\!-\!\eta'$ mixing effect depends highly on four strong phases which are non-perturbative in nature, a definitive conclusion on this point is unavailable currently. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>This study measured the yields of the radionuclides 82Sr, 83(m+g)Sr, 85mSr, 85gSr, 87mSr, 81(g+0.976m)Rb, 82mRb, 83gRb, 84(m+g)Rb, and 86(m+g)Rb produced in natSr(γ,xnyp) multiparticle reactions with bremsstrahlung end-point energies of 55-, 60-, and 65-MeV. The bremsstrahlung radiations were generated using the 100-MeV electron linac at the Pohang accelerator laboratory, Korea, and the reaction yields were derived from the induced activities measured using off-line γ-ray spectrometry. To obtain accurate experimental results, we made the necessary γ-ray interference corrections. The experimental results were compared with the theoretical predictions obtained using the TALYS-1.95 statistical nuclear model code. The calculations were performed using six different level-density models to ascertain which model best fitted the experimental results. The dependence of the reaction yield on the incident bremsstrahlung energy and on the number of nucleons emitted by the photonuclear reactions was also investigated.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We study the application of BCFW recursion relations to the QED processes $0\to e^- e^+ n \gamma$. Based on 6-point amplitudes (both MHVA and NMHVA) computed from Feynman diagrams in the Berends-Giele gauge, we conduct a comprehensive study on all different shifts. Then we propose a new shift (LLYZ shift) which can lead to the full amplitudes for these processes and can have some realistic computation advantages. We compare the number of terms and the independent amplitudes of this novel shift with a few typical shifts. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>This paper is asserted to observe the models of traversable wormhole in $f(R)$ theories of gravity by applying the karmarkar condition. For this purpose, we consider the spherically symmetric space-time to examine the structure of wormholes. First, we examine the wormhole and its geometry by using the redshift function under various conditions. Then we discuss the embedding diagram of the upper and lower universe concerning radial coordinates in two and three-dimensional Euclidean affine space. Three exclusive models are taken into account of $f(R)$ theories of gravity and observe the radial and tangential pressures. Furthermore, by taking a definite shape function, we observe the behavior of energy conditions. We examine that energy conditions are violated, and their violation is generic and represents the presence of exotic matter. According to Einstein's field theory, the existence of wormholes is predicated on the occurrence of rare material. Hence, we conclude that our work is more realistic and stable.</jats:p>