EINN2025

Kaon semileptonic form factors at the physical quark masses on large volumes in lattice QCD

Not scheduled

20m

Talk in workshop 1 "Non-perturbative approaches for hadron structure from low to high energy"

Speaker

Takeshi Yamazaki (University of Tsukuba)

Description

We present our results for the kaon semileptonic form factors calculated
by using the $N_f=2+1$ and $2+1+1$ PACS10 configuration, whose physical volumes
are more than $($10 fm$)^4$ at the physical quark masses in the lattice spacings
from 0.04 to 0.08 fm. The configurations were generated using the Iwasaki
gauge action and stout-smeared clover quark action. The form factors near
zero momentum transfer can be calculated thanks to the large volume.
Using our data, a stable interpolation of the form factors to zero momentum
transfer is carried out. The value of $|V_{us}|$ is determined using
the interpolated result of the form factors at zero momentum transfer.
Our value of $|V_{us}|$ is compared with a prediction of the standard model
estimated from the CKM matrix unitarity and with those determined using
the previous lattice results.