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Based on the back-propagation neural networks and density functional theory, a supervised learning is performed firstly to generate the nuclear charge density distributions. The charge density is further calibrated to the experimental charge radii by a composite loss function. It is found that, when the parity, pairing, and shell effects are taken into account, about $96\%$ of the nuclei in the validation set fall within two standard deviations of the predicted charge radii. The calibrated charge density is then mapped to the matter density, and further mapped to the binding energies according to the Hohenberg-Kohn theorem. It provides an improved description of some nuclei in both binding energies and charge radii. Moreover, the anomalous overbinding in $^{48}$Ca implies the existence of an indispensable beyond-mean-field effect.

In this work, we investigate the next-to-leading order (NLO) QCD correction to $J/��$ associated production with a bottom quark pair from the Higgs boson decay within the nonrelativistic QCD framework. From numerical results, {we find that the decay width of process $H \rightarrow b+ J/��+\bar{b}$ at leading order (LO) mainly comes from the contribution of the Fock state $^3S^{(8)}_1$, and the NLO QCD corrections significantly enhance the decay width at LO accuracy by about 2 times. At NLO accuracy, the Fock states $^3S^{(8)}_1$ and $^3P^{(8)}_J$ channels give the main contribution, accounting for about $68\%$ and $29\%$ of the total decay width of $J/��$ associated production with a bottom quark pair at NLO accuracy from the Higgs boson decay, respectively. Considering the dominant contribution of color octet (CO) channels at NLO accuracy, the inclusive decay process $H\to b+J/��+\bar b + X$ has the potential to be found in future colliders with high energy/luminosity.} The study of $J/��$ associated production with a bottom quark pair from the Higgs boson decay is not only useful to study the mechanism of color-octet, but also to assist in the investigation of the coupling for the Higgs boson with the bottom quark., 11 pages, 6figures, Accepted by Phys. Rev. D

Rare information on photodisintegration reactions of nuclei with mass numbers $A \approx 160$ at astrophysical conditions impedes our understanding of the origin of $p$-nuclei. Experimental determination of the key ($p,\gamma$) cross sections has been playing an important role to verify nuclear reaction models and to provide rates of relevant ($\gamma,p$) reactions in $\gamma$-process. In this paper we report the first cross section measurements of $^{160}$Dy($p,\gamma$)$^{161}$Ho and $^{161}$Dy($p,n$)$^{161}$Ho in the beam energy range of 3.4 - 7.0 MeV, partially covering the Gamow window. Such determinations are possible by using two targets with various isotopic fractions. The cross section data can put a strong constraint on the nuclear level densities and gamma strength functions for $A \approx$ 160 in the Hauser-Feshbach statistical model. Furthermore, we find the best parameters for TALYS that reproduce the A $\thicksim$ 160 data available, $^{160}$Dy($p,\gamma$)$^{161}$Ho and $^{162}$Er($p,\gamma$)$^{163}$Tm, and recommend the constrained $^{161}$Ho($\gamma,p$)$^{160}$Dy reaction rates over a wide temperature range for $\gamma$-process network calculations. Although the determined $^{161}$Ho($\gamma$, p) stellar reaction rates at the temperature of 1 to 2 GK can differ by up to one order of magnitude from the NON-SMOKER predictions, it has a minor effect on the yields of $^{160}$Dy and accordingly the $p$-nuclei, $^{156,158}$Dy. A sensitivity study confirms that the cross section of $^{160}$Dy($p$, $\gamma$)$^{161}$Ho is measured precisely enough to predict yields of $p$-nuclei in the $\gamma$-process., Comment: 12 pages,9 figures

Rare information on photodisintegration reactions of nuclei with mass numbers $A \approx 160$ at astrophysical conditions impedes our understanding of the origin of $p$-nuclei. Experimental determination of the key ($p,��$) cross sections has been playing an important role to verify nuclear reaction models and to provide rates of relevant ($��,p$) reactions in $��$-process. In this paper we report the first cross section measurements of $^{160}$Dy($p,��$)$^{161}$Ho and $^{161}$Dy($p,n$)$^{161}$Ho in the beam energy range of 3.4 - 7.0 MeV, partially covering the Gamow window. Such determinations are possible by using two targets with various isotopic fractions. The cross section data can put a strong constraint on the nuclear level densities and gamma strength functions for $A \approx$ 160 in the Hauser-Feshbach statistical model. Furthermore, we find the best parameters for TALYS that reproduce the A $\thicksim$ 160 data available, $^{160}$Dy($p,��$)$^{161}$Ho and $^{162}$Er($p,��$)$^{163}$Tm, and recommend the constrained $^{161}$Ho($��,p$)$^{160}$Dy reaction rates over a wide temperature range for $��$-process network calculations. Although the determined $^{161}$Ho($��$, p) stellar reaction rates at the temperature of 1 to 2 GK can differ by up to one order of magnitude from the NON-SMOKER predictions, it has a minor effect on the yields of $^{160}$Dy and accordingly the $p$-nuclei, $^{156,158}$Dy. A sensitivity study confirms that the cross section of $^{160}$Dy($p$, $��$)$^{161}$Ho is measured precisely enough to predict yields of $p$-nuclei in the $��$-process., 12 pages,9 figures

The production of charmonium associated with Higgs boson via gluon fusion has been investigated in Ref.[Phys.Rev.D66,114002(2002)], in which they considered the contribution of final Higgs boson radiation off the charm quark at tree level and found that this process is to be far too rare to be observable in any of the considered experiments. In this paper, the production of prompt $J/��$ associated with Higgs boson via gluon fusion at the 14 TeV LHC within the factorization formalism of NRQCD is revisited. After considering the contribution from the final Higgs boson radiation off the top quark in the loop, which is {more than} three orders of magnitudes over the charm quark at tree level, the production of prompt $J/��$ associated with Higgs boson has great potential to be detected. The prompt $J/��$ production includes the direct production and indirect production via radiative or hadronic decays of high excited charmonium states. For the direct $J/��+ H$ production via gluon fusion loop-induced, the ${}^{3}S^{(8)}_1$ Fock state gives dominant contribution to the cross section, which is about 95\% to the total direct production. The indirect contribution via loop-induced is appreciable, since the summation of which from $��(2S) + H$, $��_{c1} + H$ and $��_{c2} + H$ is about $34\%$ to the total cross section of prompt $J/��+ H$. While the indirect contribution from $��_{c0} + H$ is tiny, which can be neglected. With the great potential to be detected, prompt $J/��$ production in associated with Higgs boson can help us to further understand the mechanism of colour-octet, as well as can be useful to further investigate the coupling of the Higgs boson and fermion., 11 pages, 5 figures, 4 tables. Accepted by Physical Review D

Resonance plays critical roles in the formation of many physical phenomena, and several methods have been developed for the exploration of resonance. In this work, we propose a new scheme for resonance by solving the Dirac equation in complex momentum representation, in which the resonant states are exposed clearly in complex momentum plane and the resonance parameters can be determined precisely without imposing unphysical parameters. Combining with the relativistic mean-field theory, this method is applied to probe the resonances in $^{120}$Sn with the energies, widths, and wavefunctions being obtained. Comparing with other methods, this method is not only very effective for narrow resonances, but also can be reliably applied to broad resonances., Comment: 6 pages, 5 figures

Resonance plays critical roles in the formation of many physical phenomena, and many techniques have been developed for the exploration of resonance. In a recent letter [Phys. Rev. Lett. 117, 062502 (2016)], we proposed a new method for probing single-particle resonances by solving the Dirac equation in complex momentum representation for spherical nuclei. Here, we extend this method to deformed nuclei with theoretical formalism presented. We elaborate numerical details, and calculate the bound and resonant states in $^{37}$Mg. The results are compared with those from the coordinate representation calculations with a satisfactory agreement. In particular, the present method can expose clearly the resonant states in complex momentum plane and determine precisely the resonance parameters for not only narrow resonances but also broad resonances that were difficult to obtain before., Comment: 10pages,7figures

Nuclear single-proton resonances are sensitive to the Coulomb field, while the exchange term of Coulomb field is usually neglected due to its nonlocality. By combining the complex scaling method with the relativistic mean-field model, the influence of the Coulomb exchange term on the single-proton resonances is investigated by taking Sn isotopes and $N=82$ isotones as examples. It is found that the Coulomb exchange term reduces the single-proton resonance energy within the range of $0.4-0.6$ MeV, and lead to similar isotopic and isotonic trends of the resonance energy as those without the Coulomb exchange term. Moreover, the single-proton resonance width is also reduced by the Coulomb exchange term, whose influence generally decreases with the increasing neutron number and increases with the increasing proton number. However, the influence of the Coulomb exchange term cannot change the trend of the resonance width with respect to the neutron number and proton number. Furthermore, the influence of the Coulomb exchange term on the resonance width is investigated for the doubly magic nuclei $^{40}$Ca, $^{56,78}$Ni, $^{100,132}$Sn, and $^{208}$Pb. It is found that the Coulomb exchange term reduces the proton resonance width within $0.2$ MeV, whose magnitude depends on the specific nucleus and the quantum numbers of resonant states., Comment: 6 pages, 6 figures

The similarity renormalization group is used to transform a general Dirac Hamiltonian into diagonal form. The diagonal Dirac operator consists of the nonrelativistic term, the spin-orbit term, the dynamical term, and the relativistic modification of kinetic energy, which are very useful to explore the symmetries hidden in the Dirac Hamiltonian for any deformed system. As an example, the relativistic symmetries in an axially deformed nucleus are investigated by comparing the contributions of every term to the single particle energies and their correlations with the deformation. The result shows that the deformation considerably influences the spin-orbit interaction and dynamical effect, which play a critical role in the relativistic symmetries and its breaking., Comment: Some suggestions and comments are welcome

The properties of neutron stars are investigated by including $��$ meson field in the Lagrangian density of modified quark-meson coupling model. The $��^-$ population with $��$ meson is larger than that without $��$ meson at the beginning, but it becomes smaller than that without $��$ meson as the appearance of $��^-$. The $��$ meson has opposite effects on hadronic matter with or without hyperons: it softens the EOSes of hadronic matter with hyperons, while it stiffens the EOSes of pure nucleonic matter. Furthermore, the leptons and the hyperons have the similar influence on $��$ meson effects. The $��$ meson increases the maximum masses of neutron stars. The influence of $(��^*,��)$ on the $��$ meson effects are also investigated., 10 pages, 6 figures, 4 tables

The influences of uncertainties in nuclear physics inputs on the Th/U, Th/Hf, Th/Eu, Th/Os, Th/Ir nucleo-chronometers are investigated in the framework of the classical r-process approach. A Monte-Carlo method is used to evaluate the age uncertainty originating from neutron separation energies for each nuclear mass model. It is found that the deduced age uncertainty for Th /U can be up to 1.66 Ga, and for the three chronometers, Th/Eu, Th/Os, Th/Ir, the uncertainties are 5.15 Ga, 3.93 Ga and 3.95 Ga, respectively. The recently proposed chronometer, Th/Hf, shows a clear model dependence, while Th/Os and Th/Ir chronometers tend to overestimate the age of Universe. Taking into account the uncertainties in nuclear physics inputs and observations, an up-to-date age estimation for the universe with the Th/U chronometer is 14.1? 3.8 Ga.

The rapid neutron-capture process (r-process), which is an interdisciplinary field of astrophysics and nuclear physics, is bound up with various characteristics of thousands of neutron-rich exotic nuclei, such as nuclear masses, and the relevant reactions. By employing the WLW microscopic-macroscopic nuclear mass model developed recently, the solar r-process abundance distribution is well reproduced in the classical r-process approach. In comparison with the well known FRDM model, the present calculation better pictures the nuclear region of A135 and A180, and especially avoids the abundance peaks at A135 often obtained in other calculations. The improvement in the r-process calculation may indicate a more suitable description of the evolution of shell structure and symmetry energy towards the drip line in the WLW model.

The contrast of birefringence images of dislocation in synthetic quartz crystal have been calculated with anisotropic elasto-optical coeffficients. Using reflection polarizing microscopy to compensate the natural optical activity, along the optical axis, we obtained the images of edge dislocations and compared it with the calculation.