2025 CAP Congress / Congrès de l'ACP 2025

New physics searches with the PIONEER experiment

11 Jun 2025, 14:15

30m

Rm 134 (cap.154) (Arts Bldg., U.Sask.)

Invited Speaker / Conférencier(ère) invité(e) Symposia Day (PPD - PPD) - Flavour Physics & Beyond / La physique des saveurs et au-delà (PPD) W2-4 Flavour Physics & Beyond | La physique des saveurs et au-delà (PPD)

Speaker

Chloe Malbrunot (TRIUMF)

Description

Pions are fantastic tools to look for new physics. The PIENU experiment at TRIUMF (data completion in 2012) has provided, to date, the most precise experimental determination
of $R_{e/\mu }^{\pi }$ , the ratio of pions decaying to positrons relative to muons. While more than an order of magnitude less precise that the Standard Model (SM) calculation, the PIENU result is a precise test of the universality of charged leptons interaction, a key principle of the SM, constrains a large range of new physics scenario, and allows dedicated searches for exotics such as sterile neutrinos. I will present a short overview of the new physics constraints provided by $R_{e/\mu }^{\pi }$ measurements and introduce the next generation precision pion decay experiment in the making: PIONEER. This newly proposed experiment aims at pushing the boundaries of precision on $R_{e/\mu }^{\pi }$ and expanding the physics reach by improving on the measurement of the very rare pion beta decay ${\pi }^{+}\to {\pi }^0{e}^{+}\nu$. This will provide a new and competitive input to the determination of $|V_{ud}|$, an element of the Cabibbo- Kobayashi-Maskawa (CKM) quark-mixing matrix.

Presentation materials

PIONEER_Malbrunot_CAP2025.pdf