AcceLerated PreCision Tests of Lepton UniversAlity

The Standard Model (SM) of particle physics describes most fundamental phenomena extraordinarily well, but unresolved questions such as the matter-antimatter asymmetry remain.

New Physics (NP), able to resolve these questions, has not been found in direct searches yet, so it must be either extremely rare or manifest at higher energies that can only be probed by precision SM measurements.Lepton flavor universality (LFU) is one of the most precise predictions of the SM, but discrepancies with measurements have emerged in decays of B hadrons.

Unambiguously establishing the presence of LFU breaking effects is therefore one of the most vital and timely challenges in HEP. However the current experimental precision is not sufficient for a discovery due to the limited size of data sets. Therefore, the LHCb experiment at CERN is being upgraded to measure B hadrons at higher rates.

But at these rates, efficient selection of signals requires exceptional computing demands. CPU-based systems no longer meet these demands, so real-time selection constitutes a major bottleneck.

The Allen system, that I have pioneered and led from proof-of-concept to the new LHCb baseline implementation, solves this by using graphics processing units, and even provides a large head-room in computing resources.With ALPaCA I will build a team to demonstrate that the experimental precision of LFU observables required to establish the presence of NP is reached by using accelerated real-time analysis systems.

We will: 1. Enhance Allen using the extra computing resources to increase the data samples for LFU observables by a factor two. 2. Test LFU in ratios of branching fractions of b -> c l nu transitions with electrons for the first time at LHCb. 3. Characterize NP by measuring angular observables of b -> c tau nu transitions at LHCb.4.

Direct the design of future experiments and facilities by unlocking new computing potential.