Triggering on W, Z Boson Jets

The ATLAS trigger performs well for the hadronisation of isolated quarks or gluons, but is not optimised for $\text{W}^\pm$ and $\text{Z}^0$ jets. This can be done with substructure techniques. As the W and Z bosons are highly boosted, the pair of quarks from their decay is heavily collimated and cannot be separated. The result is one single large jet with substructure. As it has two regions in the jet with high energy density (cores), while quarks have only one and gluons have two but a low mass, the existence of two cores plus a mass cut can be used to trigger on the hadronic decay of W and Z. In this project, it was investigated whether an offline tagger for W and Z bosons can be used as a trigger. Trimming, calibration and a tighter mass cut were applied to the jets and the trigger and offline reconstruction performance were compared.