Search for squarks and gluinos in final states with an isolated lepton, jets, and missing transverse momentum at $\sqrt{s}=13$ TeV with the ATLAS detector

The results of a search for gluino and squark pair production $pp \rightarrow \tilde{q}\tilde{q}$, $pp \rightarrow \tilde{g}\tilde{g}$ decaying via charginos ($\tilde\chi^\pm_1$) to a final state consisting of a $W$ boson, the lightest neutralino ($\tilde\chi^0_1$), and quarks are presented. The signal is characterized by the presence of a single charged lepton from a $W$ boson decay, jets, and missing transverse momentum. The analysis was performed using proton-proton collision data taken at a center-of-mass energy $\sqrt{s}=13$~TeV provided by the Large Hadron Collider and recorded by the ATLAS experiment, corresponding to 139~fb$^{-1}$. No statistically significant excess of events above the Standard Model expectation is found. Limits are set on the direct production of squarks and gluino in the simplified models: masses of $\tilde{g}$ ($\tilde{q}$) up to 2.2 TeV (1.37 TeV) are excluded at 95\% confidence level.