$e^+e^- \rightarrow s\bar{s}$ at $\sqrt{s} = 250$ GeV at future linear colliders

Abstract: The forward--backward asymmetry ($A_{FB}$) in light-quark production is a sensitive probe of the electroweak sector and potential flavour-dependent BSM effects. We present a study of $e^{+e^-} \rightarrow s\bar{s}$ at $\sqrt{s}=250$ GeV at future linear colliders, using full ILD simulation and reconstruction tools for ILC and LCF@CERN. We assess the impact of particle identification on charge reconstruction and $A_{FB}$ extraction, considering software improvements using Comprehensive PID (CPID) for optimal $dE/dx$ usage, as well as hardware scenarios including cluster counting ($dN/dx$) and ideal TPC performance. Statistical precision gains are evaluated, with corrections for charge misidentification and acceptance applied. Results indicate that precise $A_{FB}<sup>{s\bar{s}}$ measurements are feasible and that advanced PID is key to maximising sensitivity to electroweak and new-physics effects.