Department of Physics & Astronomy
University of New Mexico

Nuclear, Particle, Astroparticle and Cosmology (NUPAC) Seminars

Study of the rare decays B0(S) →μ-μ+ with ATLAS and development of detectors for future particle physics experiments

Presented by Joey Sorenson

The rare decays B0 →μ-μ+ and B0S →μ-μ+ have measurable deviations of their rates from the Standard Model (SM) predictions in many Beyond the Standard Model (BSM) extensions. The SM predictions for these decays differed by about 2 standard deviations with the most recent combined LHC results. The branching ratio measurement uses the reference channel B± →J/𝜓K+. I will discuss data analysis methods for extraction of the reference channel yield, including Monte Carlo modeling, simultaneous functional fits, and systematic error extraction for the partial Run 2 analysis and for analysis which is in development for the Full Run 2 data. As a second topic, I introduce the HL-LHC upgrade, which will increase the luminosity by a factor of 10 resulting in increased pileup and fluence applied to the detector. In response to increased pileup, the high granularity timing detector (HGTD) is being installed in the forward regions of the ATLAS detector to improve the timing resolution on tracks. The HGTD will be made of Low Gain Avalanche Detectors (LGADs) which have excellent timing performance. Their radiation hardness is still improving and is the goal of my research. I will present studies on LGAD prototypes exposed to the full HL-LHC expected hadron dose. In a third topic, I introduce the ATLAS Inner Detector replacement by the Inner Tracker (ITk) which will be made of 3D and planar silicon sensors. I will present studies on the noise characteristics of the 3D sensors.

2:00 pm, Tuesday, February 13, 2024

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