Volume 390 - 40th International Conference on High Energy physics (ICHEP2020) - Posters: Operation, Performance and Upgrade of Present Detectors
Luminosity Determination using Z->ll events atp𝒔=13TeV with the ATLAS detector
M.W. O'Keefe* on behalf of the ATLAS collaboration
*corresponding author
Full text: pdf
Pre-published on: February 12, 2021
Published on:
Abstract
During Run 2, the LHC delivered instantaneous luminosities of approximately $10^{34}\ \textrm{cm}^{-2} \textrm{s}^{-1}$ at $\sqrt{s}=13$ TeV in $pp$ collisions. At such high instantanenous luminosities, measuring the decay rate of $Z\to\ell\ell$ provides a powerful tool to monitor the luminosity recorded by ATLAS over time periods as short as 60s.These proceedings present an overview of the method, outlining the event selection, data-driven efficiency determination and corrections derived from simulation, as well as showcasing the robustness of the final results. The absolute luminosities obtained independently in both the $Z\to ee$ and $Z\to\mu\mu$ channels agree to within approximately 1\%, with an excellent time stability of around 0.5\%, a non-trivial result considering both channels have their own distinct chain of corrections. The difference between the normalised $Z$-counting luminosity and ATLAS baseline luminosity, where the $Z$-counting luminosity is normalised to the same integrated luminosity as the ATLAS baseline measurement over the entire data-taking period, is evaluated per LHC fill and found to typically be within 0.5\%.
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access