arXiv subjects

Qi-Wei Yuan

Publications and source records attributed to Qi-Wei Yuan.

3 recordsLinked to original sources

arXiv2026

Decay constants of the two-pole $D_0^*(2300)$

The nature of the scalar charmed meson $D_0^*(2300)$ remains one of the most intriguing states in hadron spectroscopy. A prominent interpretation is a two-pole structure generated by the coupled channels $Dπ$, $Dη$, $D_s\bar K$, and $Dη'$, in which the lower pole couples mainly to $Dπ$ and the higher pole to $D_s\bar K$. Following this picture, we calculate the decay constants of these two poles using the effective Lagrangian approach. The resulting values, $f_{D_0^*}^{(\mathrm{lower})}=64.6^{+0.9}_{-1.0}\,\mathrm{MeV}$ and $f_{D_0^*}^{(\mathrm{higher})}=80.8^{+9.6}_{-5.3}\,\mathrm{MeV}$, are substantially smaller than those predicted by conventional $c\bar q$ excited-state scenarios. This difference suggests that decay constants can serve as a sensitive probe to discriminate between different internal structures of the $D_0^*(2300)$. As a phenomenological application, we further predict the branching fractions for the Cabibbo-favored decays $B_s \to D_s D_0^*$, $Λ_b \to Λ_c D_0^*$, and $Ξ_b \to Ξ_c D_0^*$ within the factorization approach. These predictions provide crucial tests to validate the two-pole interpretation of the $D_0^*(2300)$.

hep-ph↗

arXiv2026

Solving the Inverse Source Problem in Femtoscopy with a Toy Model

Hadron-hadron interactions, as a non-perturbative effect, play a significant role in understanding phenomenological problems in particle physics. Femtoscopy is a powerful tool in heavy-ion collision experiments, enabling the extraction of hadron-hadron interactions via momentum-correlation functions (CFs). These CFs are generally factorized into a convolution of source functions and hadron-hadron wave functions, with the latter encoding information about hadron-hadron interactions. However, source functions remain ambiguous and are commonly approximated by a Gaussian form. Reconstructing source functions from experimental correlation data constitutes an ``inverse problem." To address it, we propose a toy model based on the Tikhonov regularization. Employing a square potential well of four distinct potential strengths, we calculate the CFs for inputs of a Gaussian source function and its hybrid form. The obtained CFs are subsequently used to reconstruct the source functions via the Tikhonov regularization. Our results demonstrate that the Gaussian source function can be successfully reconstructed, indicating the potential of this approach for extracting realistic source functions of hadron pairs of interest in the future.

hep-ph↗

arXiv2025

$B$ meson decays to vector charmonium(like) states and a $K$ meson: the role of final-state interactions

A series of vector charmonium(like) states, accompanied by a $K$ meson, have been observed in the decays of $B$ meson. These processes are color-suppressed at the quark level, as inferred from topological diagram analysis. In this work, we calculate the branching fractions of the decays $B \to ψK$, where $ψ$ denotes the charmonium(like) states $ψ(1S)$, $ψ(2S)$, $ψ(4040)$, $ψ(3770)$, and $ψ(4160)$. Our analysis incorporates both short-distance (naive factorization approach) and long-distance (final-state interactions) contributions. Within reasonable parameters, our results align with experimental data except for the $ ψ(4160)$, suggesting its possible exotic nature. Furthermore, we find that long-distance contributions dominate these decay processes, highlighting the crucial role of final-state interactions in the productions of charmonium(like) states in $B$ decays.

hep-ph↗