Rencontres de Physique des Particules 2026

Session

Neutrinos

11 mars 2026, 16:40

31. Review talk: Neutrinos

Salvador ROSAURO-ALCARAZ (LPCA-CNRS)

11/03/2026 16:40

32. Primordial lepton asymmetries: new constraints and consequences for sterile neutrino dark matter

M. Julien Froustey (Institut d'Astrophysique de Paris (IAP))

11/03/2026 17:20

Resonant production via active–sterile neutrino oscillations in the presence of large lepton asymmetries (the Shi–Fuller mechanism) remains a compelling scenario for keV-scale sterile neutrino dark matter. For a long time, the constraints on such asymmetries were obtained thanks to big bang nucleosynthesis and cosmic microwave background measurements, but did not properly account for the...

33. Neutrino interaction rates at MeV temperatures and their role in decoupling

Greg Jackson (SUBATECH (CNRS/IN2P3))

11/03/2026 17:40

The dynamics of neutrinos and antineutrinos at MeV temperatures sets the Standard Model prediction for the effective number of relativistic species, N_{eff}, a key target for upcoming CMB and BBN measurements. Reaching a suitable theoretical accuracy demands control over sub-percent effects in the relevant interaction rates. In this talk I will review recent progress on precision calculations...

39. Long-Lived Particles from Meson and Muon Decays at Rest at Spallation Sources

Salvador URREA GONZALEZ

11/03/2026 18:00

We provide a systematic survey of spallation sources around the world and their potential to search for new light particles. We study the sensitivity of existing neutrino detectors to the decay in flight of light particles produced in the decay at rest of pions, muons, and kaons. At J-PARC, we show that the magnetized gaseous argon detectors of ND280 could place leading limits on light...