Hardware tracking for ATLAS at the HL-LHC and a search for third generation scalar leptoquarks with the ATLAS detector

The High Luminosity upgrade of the Large Hadron Collider at CERN will increase the instantaneous luminosity delivered to the ATLAS detector with a factor of 5 to 7. To benefit from this, the trigger rates have to be kept at manageable levels while maintaining or lowering the trigger pT-thresholds. The Hardware Tracking for the Trigger (HTT) system is a key component to make this happen. The HTT is based on custom-made Associative Memory (AM) Application-Specific Integrated Circuits (ASICs). However, since the development of custom ASICs is inherently risky, alternative methods for hardware tracking have to be investigated. This talk describes such a method based on the Hough transform with the potential to be implemented in commercially available Field Programmable Gate Arrays (FPGAs).

The second part of the talk describes a search for pair-produced third generation scalar leptoquarks, each decaying into a b-quark and a tau-lepton, using 36.1 fb^-1 of data collected by ATLAS at a center-of-mass energy of 13 TeV. Leptoquarks are well motivated by a variety of beyond the standard model theories as well as recent tensions with respect to the standard model observed in B-mesons decaying to D-mesons by BaBar, LHCb, and Belle.