Selected strong decays of pentaquark State Pc(4312)P_c(4312) in a chiral constituent quark model

The newly confirmed pentaquark state $P_c(4312)$ has been treated as a weakly bound $(\Sigma_c\bar{D})$ state by a well-established chiral constituent quark model and by a dynamical calculation on quark degrees of freedom where the quark exchange effect is accounted for. The obtained mass $4308$ MeV agrees with data. In this work, the selected strong decays of the $P_c(4312)$ state are studied with the obtained wave function. It is shown that the width of the $\Lambda_c\bar{D}^*$ decay is overwhelmed and the branching ratios of the $p\,\eta_c$ and $p\,J/\psi$ decays are both less than 1 percentage.Comment: 13 pages, 2 figures, 3 table

Decay width of d∗(2380)→NNπd^*(2380) \to NN \pi process in a chiral constituent quark model

The width of three-body single-pion decay process $d^*\to NN\pi^{0,\pm}$ is calculated by using the $d^*$ wave function obtained from our chiral SU(3) constituent quark model calculation. The effect of the dynamical structure on the width of $d^*$ is taken into account in both the single $\Delta\Delta$ channel and coupled $\Delta\Delta+CC$ two-channel approximations. Our numerical result shows that in the coupled-channel approximation, namely, the hidden-color configuration being considered, the obtained partial decay width of $d^*\to NN\pi$ is about several hundred $\rm {KeV}$, while in the single $\Delta\Delta$ channel it is just about $2\sim 3~\rm{MeV}$. We, therefore, conclude that the partial width in the single-pion decay process of $d^*$ is much smaller than the widths in its double-pion decay processes. Our prediction may provide a criterion for judging different interpretations of the $d^*$ structure, as different pictures for the $d^*$ may result quite different partial decay width.Comment: 6 pages, 1 figure, and 1 table, typos correcte

Spatial Combination Modeling Framework of Saturation-Excess and Infiltration-Excess Runoff for Semihumid Watersheds

There exist two types of direct runoff generation mechanisms in semihumid watersheds: saturation-excess mechanism and infiltration-excess mechanism. It has always been a difficult problem for event hydrological simulation to distinguish the two types of runoff processes. Based on the concept of dominant runoff processes, combined with GIS and RS techniques, this paper proposed an event-based spatial combination modeling framework and built two spatial combination models (SCMs) accordingly. The CN parameter and topographic index, both of which are widely used in hydrological researches, are adopted by the SCM to divide the entire watershed into infiltration-excess dominated (IED) areas and saturation-excess dominated (SED) areas. Dongwan watershed was taken as an example to test the performances of infiltration-excess model, saturation-excess model, and SCM, respectively. The results of parameter optimization showed that the parameter values and state variables of SCM are much more realistic than those of infiltration-excess model and saturation-excess model. The more accurate the divisions of infiltration-excess and saturation-excess dominated areas, the more realistic the SCM parameter values. The simulation results showed that the performance of SCM was improved in both calibration and validation periods. The framework is useful for flood forecasting in semihumid watersheds

Daily streamflow simulation based on the improved machine learning method

Kan, G., He, X., Ding, L., Li, J., Hong, Y., Ren, M., Lei, T., Liang, K., Zuo, D., & Huang, P. (March-April, 2017). Daily streamflow simulation based on the improved machine learning method. Water Technology and Sciences (in Spanish), 8(2), 51-60. Daily streamflow simulation has usually been implemented by conceptual or distributed hydrological models. Nowadays, hydrological data, which can be easily obtained from automatic measuring systems, are more than enough. Therefore, machine learning turns into an effective and popular tool which is highly suited for the streamflow simulation task. In this paper, we propose an improved machine learning method referred to as PKEK model based on the previously proposed NU-PEK model for the purpose of generating daily streamflow simulation results with better accuracy and stability. Comparison results between the PKEK model and the NU-PEK model indicated that the improved model has better accuracy and stability and has a bright application prospect for daily streamflow simulation tasks

IONIC CONDUCTIVITY OF Li2O-(LiCl)2-B2O3-Al2O3 GLASSES

La conductivité ionique, la compressibilité dynamique, les spectres infrarouges et Raman, ainsi que les propriétés d'échange ionique Li+ -H+ ont été étudiés pour les verres du système Li2O-(LiCl)2-B2O3-Al2O3. La propriété électrique a été interprétée au point de vue de la structure du verre.The ionic conductivity, dynamical compressibility, IR and Raman spectra, as well as Li+ -H+ ion exchange property were investigated for Li2O-(LiCl)2-B2O3-Al2O3 glasses. The electrical property was interpretated from the point of view of glass structure

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