Speaker
Description
We present a calculation of the form factors for the kaon semileptonic decay process using the $N_f=2+1+1$ PACS10$_c$ configurations. These configurations are generated with the Iwasaki gauge action and the $N_f=2+1+1$ stout-smeared nonperturbatively $O(a)$ improved Wilson quark action at the three lattice spacings, 0.08, 0.06, and 0.04 fm. The spatial volume of the configurations is larger than (10 fm)$^3$ and the masses for the light, strange, and charm quarks are tuned to be close to their physical values. Using our data, we discuss the momentum transfer interpolation and the continuum extrapolation for the form factors. Our preliminary value of $|V_{us}|$ is estimated in the continuum limit, and compared with our previous $N_f = 2+1$ result, those from other lattice groups, and the value obtained from the kaon leptonic decay process.