arXiv subjects

Yi-Lin Song

Publications and source records attributed to Yi-Lin Song.

3 recordsLinked to original sources

arXiv2025

Decays of $\Upsilon(10860)$ and $\Upsilon(10753)$ into $\omega\chi_{bJ}$

In this paper, we model $\Upsilon(10753)$ as a $4S$-$3D$ bottomonium mixture and $\Upsilon(10860)$ as a $5S$-$4D$ mixture, and predict the properties of a new bottomonium state, $\Upsilon(10950)$, as the mixing partner of $\Upsilon(10860)$. The mixing angles are derived from dielectron decay widths and mass shifts of these bottomonia. We consider open-bottom meson loops in the decays of the $D$-wave bottomonium components, based on a nonrelativistic effective field theory power counting. We show that the $S$-$D$ mixing scheme is consistent with the experimental data of the decays of $\Upsilon(10860)$ into $\omega\chi_{bJ}$ ($J=0,1,2$) and $\Upsilon(10753)$ into $\omega\chi_{bJ}$ ($J=1,2$). Predictions for the dielectron widths and partial decay widths into $\chi_{bJ}\omega$ for $\Upsilon(10753)$ and $\Upsilon(10950)$ are presented.

hep-ph↗

arXiv2025

Production of $J/\psi p \bar p$ in electron-positron collisions

The discoveries of the hidden-charm $P_c$ pentaquarks by the LHCb Collaboration have been not confirmed by other experiments yet. It is desirable to investigate the feasibility of observing them in other experiments. We present an order-of-magnitude estimate of the cross section of the $e^+e^-\to J/\psi p \bar p$ process, where the hidden-charm pentaquarks may be searched for, and find it to be of $\mathcal{O}(4~\text{fb})$ when the $e^+e^-$ c.m. energy is around 6 GeV. The cross section for $e^+e^-\to P_c \bar p$ is then estimated to be $\lesssim \mathcal{O}(0.1~\text{pb})$. Thus, it is promising to search for $P_c$ at the future high-luminosity super tau-charm facilities with annual integrated luminosity about $1~ab^{-1}$. We also predict the branching fraction of $\Upsilon\to J/\psi p\bar p$ to be of $\mathcal{O}(2\times 10^{-6})$, which can be tested at $B$ factories.

hep-ph↗

arXiv2024

Towards a precision determination of the $X(6200)$ parameters from data

In a recent paper, Phys. Rev. Lett. {\bf 126}, 132001 (2021), the LHCb data on the di-$J/\psi$ production in proton-proton collisions were analysed in a coupled-channel framework based on double-vector-charmonium channels. This investigation identified a robust pole near the $J/\psi J/\psi$ threshold, tagged $X(6200)$, suggesting it as a new state. The present work extends that investigation by incorporating recent di-$J/\psi$ production data from the CMS and ATLAS Collaborations and performing a combined analysis of all three datasets. This study confirms the existence of the $X(6200)$, and its pole position is now determined with a higher precision than in the previous study, where only a single dataset was employed. The pole corresponding to the $X(6900)$ is also extracted, though its actual position and residue depend on a particular coupled-channel model employed and deviate from values reported in the experimental investigations. Moreover, we demonstrate that the currently available data do not allow one to determine whether there is an additional pole in the studied mass range. The di-electron width of the $X(6200)$ is estimated under different conjectures on its quantum numbers, and the number of such states that can be annually produced at the future Super $\tau$-Charm Facility is estimated. The line shape in the complimentary $J/\psi\psi(2S)$ channel is discussed, and a good agreement with the ATLAS data is found.

hep-ph↗