Search for dark light mediators with short-baseline detectors at Fermilab

• Grant number: 22/10894-8
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: January 15, 2023
• End date: January 14, 2024
• Field of knowledge: Physical Sciences and Mathematics - Physics - Elementary Particle Physics and Fields
• Principal Investigator: Renata Zukanovich Funchal
• Grantee: Gustavo Figueiredo Severiano Alves
• Supervisor: Pedro Accioly Nogueira Machado
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Fermi National Accelerator Laboratory (Fermilab), United States
• Associated to the scholarship: 20/08096-0 - Exploring light dark sectors, BP.DR

Abstract

In the last few years MeV-to-GeV scale neutral vector mediators have received a lot of attention. In part this is because they can be involved in the solution of some open problems in the field. They have been evoked in association with dark matter models, with the muon anomalous magnetic dipole moment, and to alleviate the reported tension in the Hubble constant. Some years ago a model with a dark sector was proposed to explain the smallness of neutrino masses by connecting the generation of neutrino masses to a light dark sector, charged under a new U(1) dark gauge symmetry. By introducing a minimal number of dark fields (a scalar doublet, two scalar singlets and two types of dark neutrinos, all charged under the new symmetry) an anomaly free theory was constructed with spontaneous breaking of the dark symmetry, giving rise to a light vector mediator and obtaining automatically the inverse seesaw Lagrangian. As a bonus, the new light dark gauge boson provided a plausible explanation to the MiniBooNE anomaly. Most studies of light mediators are performed under simplified assumptions, in a model independent way. However, the conclusions of these general studies do not always apply to mediators in ultraviolet (UV) complete models. More often though, because of the richer phenomenology of a complete theory, there may be more signatures open to detection (and constrain) by experiments. This is why it is important to study them in UV complete models. This project aims to investigate the experimental signatures and the prospects of observation of the light mediator of the U(1) dark symmetry model by the Fermilab Short-Baseline Program liquid scintillator detectors MicroBooNE, ICARUS and SBND and the future DUNE Near Detector. (AU)