Femtoscopic correlations between hadrons provide valuable insight into the short-range dynamics of hadronic interactions, with significant implications for fundamental physics and astrophysical phenomena. The composition of neutron stars depends on the interplay between two- and three-body forces involving nucleons and hyperons. Knowledge about the latter is scarce, mainly derived from...
Measurements of the production of open heavy-flavour hadrons in high-energy heavy-ion collisions provide unique access to the transport properties of heavy quarks (charm and beauty) in the quark-gluon plasma (QGP). Charm and beauty measurements in small collision systems, such as proton–proton (pp) and proton–Pb (p–Pb) collisions, serve as a crucial test of perturbative quantum chromodynamics...
Using $(2712.4 \pm 14.3) \times 10^{6}$ $\psi(3686)$ events collected with the BESIII detector at the BEPCII collider, the decay $\eta_c \to \gamma\gamma$ in $J/\psi \to \gamma\eta_c$ is observed. We determine the product branching fraction $\mathcal{B}(J/\psi \to \gamma \eta_c) \times \mathcal{B}(\eta_c \to \gamma\gamma) = (5.23 \pm 0.26_{\text{stat.}} \pm 0.30_{\text{syst.}}) \times...
The study of transverse-spin dependent azimuthal asymmetries in the Drell-Yan process provides crucial insights into the spin-dependent structure of nucleons. In combination with semi-inclusive deep inelastic scattering, it provides a key test of the restricted universality of transverse-momentum dependent parton distribution functions, which predict that the Sivers and Boer–Mulders functions...