Among the many analyses presented were new measurements that may improve background in Higgs events. These decays need to be understood with a high degree of precision, as they appear in typical searches for the Standard Model Higgs and new physics.
Results presented by LHC experiments rencontres de moriond 2021 all in agreement with the Standard Model as shown for di-bosons decays in the image. ATLAS and CMS also presented a wide range of results that looked at the characteristics of particle jets, including new, detailed measurements of jet and di-jet cross-sections.
A high precision understanding of these jets is essential, as they form the basis for most of the measurements made by the experiments. The QCD sessions continued into the afternoon, with experiments presenting their measurements of various decays into photons.
These are used to better understand the gluon distribution function in the proton, which can also help with searches for new physics. ATLAS presented a new measurement published that same day, in fact of the cross-section of an isolated photon in association with jets, which was in good agreement with theory.
The experiment went offline back inbut improvements to theory and data models encouraged a re-examination of its data. The result was consistent with measurements by other, newer experiments — evidence that analysing old data can still deliver new results.