Project 10-140 (Derue – Kaczmarska)
“ATLAS-LPNHEIFJ-ELECINJET: Use of electrons in jets with Atlas data”
Frederic Derue (LPNHE France)

"Your signal is my background and vice versa. Use of electrons in jets with Atlas data."

The ATLAS groups of IFJ and LPNHE are participating in ATLAS physics analyses like precision measurement of the Standard Model of particle physics using W, Z, and top quark production as well as studies of the Standard Model Higgs boson, measurement of its parameters and search for physics beyond the Standard Model (BSM). In most cases, the precision of these analyses is limited by our knowledge of some ATLAS detector performances, such as the precision to which the particle energies are measured, or the efficiency with which we can identify these particles.
One of the common backgrounds in all these studies are low density jets which can mimic signal isolated leptons, which include electrons/muons from heavy flavors, electrons from Dalitz decays, muons from kaons decays, or photon conversions originating from neutral pion decays and jets in general. Leptons or charged tracks produced in b jets can be used also to reconstruct some signal final state, in particular for the top quark physics. On the other hand, they are backgrounds in BSM searches.