Speaker: Gauthier Durieux (CERN)
Title: Massive amplitude approach to the standard-model effective field theory
Host:
Zoom: https://zoom.us/j/186024391
Abstract:
On-shell methods trivialize the representation of particles to provide an efficient description of their interactions, exempt from gauge or field redefinition redundancies. Applications to effective field theories led to new insights (e.g. into non-renormalizations and theory characterizations) as well as simpler methods (e.g. for operator bases constructions). The little-group-covariant treatment of massive spinors now allows for a systematic on-shell description of the standard-model effective field theory (SMEFT) from its broken phase. Putting this program on firm grounds, we bootstrapped non-renormalizable electroweak three-point amplitudes. The electroweak symmetry was explicitly seen to emerge from the requirement of perturbative unitarity. A full example of four-point amplitude was worked out, including both factorizable and contact-term contributions. The involved construction of independent massive contact terms was then addressed. These advances pave the way for a massive amplitude approach to the SMEFT.
User:
High-Energy Seminars
Time:
4:10pm-5:10pm
Description:
Speaker: Teal Pershing, LLNL
Title: The ANNIE Experiment: Measuring the
neutron multiplicity of neutrino-nucleus
interactions
Host: Svoboda
Zoom: TBD
Abstract:Accurate modeling and tagging of inelastic charged-current neutrino interactions is critical to numerous physics measurements, including proton decay, neutrino oscillation parameter measurements, and neutrino interaction cross-section measurements. One known indicator of a neutrino interaction’s inelasticity is the presence of final-state neutrons, which are often challenging to detect. The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) is a gadolinium-doped water Cherenkov detector which is sensitive to final-state neutrons, and will measure the neutron multiplicity of neutrino charged-current interactions. ANNIE will also demonstrate the first use of Large Area Picosecond PhotoDetectors (LAPPDs) on a neutrino beam line for improved event reconstruction. This seminar will provide an overview of the ANNIE experiment and the physics motivating ANNIE’s neutron multi- plicity measurement. The experimental results from ANNIE’s background characterization will be presented, as well as the first calibration and neutrino beam data from ANNIE.
