Search

The properties of the light vector meson states around 2.0 GeV have been poorly understood for a long time, which has become a barrier to the expansion to higher light vector meson spectrum. Recently, the BESIII collaboration released the measurements of the $e^+ e^- \to ωπ^0$ and $e^+ e^- \to ρη^{\prime}$ reactions above 2.0 GeV, both of which are ideal processes to study the isovector $ρ$ meson family. In this work, through carrying out a combined analysis of the Born cross section data for the above two processes with the theoretical support on mass spectrum, and production and strong decay behaviors of the $ρ$ meson family around 2.0 GeV, we identify the enhancement structure near 2034 MeV observed in $e^+e^-\toωπ^0$ to be the interference contribution from two resonances $ρ(1900)$ and $ρ(2150)$, and another enhancement structure at 2111 MeV reported in $e^+e^-\toρη^{\prime}$ to be the contributions from $ρ(2000)$ and $ρ(2150)$. This conclusion means that the $e^+e^-\toωπ^0$ and $e^+e^-\toρη^{\prime}$ are the excellent golden channels to establish $ρ(1900)$ and $ρ(2000)$, especially for a $D$-wave state $ρ(2000)$, whose experimental search in the $e^+e^-$ collision should be quite challenging. The relevant cross section measurements with higher precision are expected in the future BESIII and Belle II experiments., 8 pages, 4 figures and 3 tables

Recently, the BaBar Collaboration reported a broad resonance structure near 2 GeV when analyzing the $e^+e^-\to f_1(1285)π^+π^-$ process, which provides a good opportunity to study the higher $ρ$-mesonic states. When considering the $ρ(1900)$ and $ρ(2150)$ contributions, the experimental data of the cross section of $e^+e^-\to f_1(1285)π^+π^-$ around 2 GeV can be well depicted, especially the observed broad resonance structure in $e^+e^-\to f_1(1285)π^+π^-$ containing two substructures is suggested by the present work. Additionally, we also indicate a possible signal of $ρ(5S)$ around 2.5 GeV in the $e^+e^-\to f_1(1285)π^+π^-$ process. The obtained result may provide a valuable hint to identify higher $ρ$ mesons, which will be a new task for the BESIII and Belle II experiments with the accumulation of higher precision data., 6 pages, 5 figures and 3 tables. Accepted by Phys. Rev. D

The $e^+e^-\to ωη$ and $e^+e^-\toωπ^0π^0$ processes are ideal platforms to search for higher $ω$ states. Focusing on the observations of two enhancement structures around 2.2 GeV existing in $e^+e^-\to ωη$ and $e^+e^-\toωπ^0π^0$ at BESIII, we analyze how the $ω(4S)$ and $ω(3D)$ states play the role in the $e^+e^-\to ωη$ and $e^+e^-\toωπ^0π^0$ processes. The present study is supported by theoretical $ω$ mesonic spectroscopy. For reproducing the data of the cross sections of $e^+e^-\toωη$ and $ωπ^0π^0$, the intermediate $ω(4S)$ and $ω(3D)$ should be introduced, which indicates that the enhancement structures around 2.2 GeV existing in $e^+e^-\toωη$ and $ωπ^0π^0$ contain the $ω(4S)$ and $ω(3D)$ signals. Nonetheless, in the process $e^+e^-\toωη$, the $ω(4S)$ plays a dominant role, while the $ω(4S)$ and $ω(3D)$ have similar sizable contributions in the process of $e^+e^-\toωπ^0π^0$, which leads to a difference in the line shape of enhancement structure in the cross sections under the interference effect. Thus, we find a solution to alleviate the puzzling difference of resonance parameter of two reported enhancement structures around 2.2 GeV existing in $e^+e^-\to ωη$ and $e^+e^-\toωπ^0π^0$ at BESIII. The present study provides valuable information to construct $ω$ meson family, which can be accessible at future experiment like BESIII., 7 pages, 8 figures and 2 tables. Accepted by PRD

Within the effective Lagrangian approach, we study the $p\bar{p} \rightarrow ����$ [$��\equiv��(3686)$, $J/��$] reaction at the low energy where the contributions from nucleon pole and low-lying nucleon resonances, $N(1520)$, $N(1535)$ and $N(1650)$ are considered. All the model parameters are determined with the help of current experimental data on the decay of $��\to p \bar{p} ��$. Within the model parameters, the total and differential cross sections of the $p\bar{p} \rightarrow ����$ reaction are predicted. We show that the relative phases between different amplitudes of different nucleon resonance will change significantly the angular distributions of the $\bar{p} p \to ����$ reaction. Therefore, we conclude that these reactions are suitable to study experimentally the properties of the low-lying nucleon resonance and the reaction mechanisms. We hope that these theoretical calculations can be tested by future experiments., 8 pages, 9 figures and 3 tables. Accepted by Phys. Rev. D

In the framework of the color-magnetic interaction model, we have systematically calculated the mass splittings for the S-wave triply heavy pentaquark states with the configuration $qqQQ\bar{Q}$ $(Q=c,b;q=u,d,s)$. Their masses are estimated and their stabilities are discussed according to possible rearrangement decay patterns. Our results indicate that there may exist several stable or narrow such states. We hope the present study can help experimentalists to search for exotic pentaquarks., Comment: 16 pages, 4 figures, 13 tables; accepted in Phys. Rev. D

As a hot issue, exploring exotic pentaquarks is full of challenges and opportunities for both theorist and experimentalist. In this work, we focus on a type of pentaquark with the $QQqq\bar{q}$ ($Q=b,c$; $q=u,d,s$) configuration, where their mass spectrum is estimated systematically. Especially, our result indicates that there may exist some stable or narrow exotic pentaquark states. Obviously, our study may provides valuable information for further experimental search for the $QQqq\bar{q}$ pentaquarks. With the running of LHCb and forthcoming Belle II, we have a reason to believe that these predictions present here can be tested., Comment: 21 pages, 5 figures, 10 tables. Accepted by Phys. Rev. C