Speaker: Simon Koch (Oxford) – Title: Measurements with ATLAS, Measurements of ATLAS: A search for leptoquarks in a final state with two tau leptons, and material measurements of the ITk Pixel detector

December 3 @ 4:00 pm - 5:00 pm

Research Progress Meeting

Date: December 3, 2024

Time: 4:00- 5:00 pm

Location: Sessler Conference Room- 50A-5132 [In-Person and HYBRID]

Speaker: Simon Koch (Oxford)

Title: Measurements with ATLAS, Measurements of ATLAS: A search for leptoquarks in a final state with two tau leptons, and material measurements of the ITk Pixel detector

Abstract: The ATLAS detector at the LHC has enjoyed great success so far, spanning both new discoveries and precision measurements, and tests of a vast array of theoretical models. This seminar will begin with an introduction to the ATLAS high-mass Drell-Yan di-tau measurement and in particular the search for leptoquarks in this decay channel, including the analysis design and expected results. The search was originally motivated by hints toward lepton-flavour-universality violating behaviour at LHCb, and the leptoquark models explored couple the lepton and quark sectors of the standard model via a new vector or scalar boson. This also introduces unique properties and challenges to the analysis, such as the impact of negative interference with the standard model cross-section.

The future should bring an even greater physics reach thanks to the larger datasets that will be made possible by the High-Luminosity LHC and the ATLAS Inner Tracker (ITk) upgrade. The tracking and vertexing performance of the ITk is critical for future analyses, and hence factors influencing detector performance must be validated so they can be correctly implemented in our Monte-Carlo simulations. One important aspect is the material content of the detector, which has a substantial impact on b-tagging and vertexing resolution due to multiple scattering and hadronic interactions, and is generally only verified using detector data post-commissioning. The second part of this seminar will explore a series of testbeam measurements utilising multiple scattering of low-energy positrons to measure 2D maps of the fractional radiation length x/X₀ of detector components to sub-mm resolution during the R&D phase. A measurement of an ITkPix quad module will be presented, and an outlook will be given on the feasibility of measuring large areas quickly and efficiently with such a technique.

Join Zoom Meeting
https://lbnl.zoom.us/j/95679892182?pwd=RU5xU2dDRFNabnR1U3pQMklkYWFIdz09

Meeting ID: 956 7989 2182

Passcode: 169037

Details

Date:: December 3
Time:: 4:00 pm - 5:00 pm