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arXiv · 2212.00255

Momentum transfer dependence of kaon semileptonic form factor on (10 fm)$^4$ at the physical point

Takeshi Yamazaki·Ken-ichi Ishikawa·Naruhito Ishizuka·Yoshinobu Kuramashi·Yusuke Namekawa·Yusuke Taniguchi·Naoya Ukita·Tomoteru Yoshié for PACS Collaboration
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Abstract

We calculate the kaon semileptonic form factors using the two sets of the PACS10 configuration, whose physical volumes are more than (10 fm)$^4$ at the physical point. The lattice spacings are 0.063 and 0.085 fm. The configurations were generated using the Iwasaki gauge action and $N_f=2+1$ stout-smeared nonperturbatively $O(a)$-improved Wilson quark action. From the momentum transfer dependence of the form factors, we evaluate the slope and curvature for the form factors at the zero momentum transfer. Furthermore, we calculate the phase space factor, which is used to obtain $|V_{us}|$ through the kaon semileptonic decay. These results are compared with previous lattice results and experimental values.

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Takeshi Yamazaki, Ken-ichi Ishikawa, Naruhito Ishizuka, Yoshinobu Kuramashi, Yusuke Namekawa, Yusuke Taniguchi, Naoya Ukita, Tomoteru Yoshié for PACS Collaboration. 2022-12-01. Momentum transfer dependence of kaon semileptonic form factor on (10 fm)$^4$ at the physical point. https://arxiv.org/abs/2212.00255

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