SBU HEP Seminar - Joseph Redeker (University of Chicago)

Monday 11 Nov 2024, 11:45 → 12:45 America/New_York

Graduate Building D-122 (Stony Brook University)

11:45 → 12:35 The search for KL → π0νν in the KOTO experiment

At the beginning of time, matter and antimatter were created in unequal
amounts, leaving a universe that is predominately composed of matter. The rea-
son for this matter-antimatter asymmetry is an open question that is intimately
tied to CP symmetry (Sakharov, 1967).
The KOTO experiment at J-PARC aims to study CP-symmetry breaking in
kaon decays. In particular, KOTO searches for the rare decay, KL → π0νν,
which is sometimes called the "Golden Mode". The mode is CP-violating, with
a theoretical branching ratio highly suppressed in the Standard Model at (2.94 ±
0.15)×10−11. With a small theoretical uncertainty, this search is highly sensitive
to new physics. During the analysis of 2021 data, no events were observed in
the signal region, which allowed KOTO to set the best upper limit on BR(KL →
π0νν) to date at < 2.01 × 10−9 (90% CL). This presentation will include details
on the analysis of KL → π0νν and on a few interesting, secondary physics
searches that have been recently published or are ongoing in KOTO.

Speaker: Joseph Redeker

The_Secrets_of_CP-Asymmetry.pdf