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arXiv · 2311.16755

$|V_{us}|$ from kaon semileptonic form factor in $N_f = 2+1$ QCD at the physical point on (10 fm)$^4$

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 present a preliminary result of the kaon semileptonic form factor calculated at the smallest lattice spacing in the PACS10 configurations, whose physical volumes are more than (10 fm)$^4$ at the physical point. The configurations were generated using the Iwasaki gauge action and $N_f=2+1$ stout-smeared nonperturbatively $O(a)$ improved Wilson quark action at the three lattice spacings, 0.085, 0.063, and 0.041 fm. The value of $|V_{us}|$ in the continuum limit is estimated from our results including the preliminary one. We compare our result of $|V_{us}|$ with the previous results and those through the kaon leptonic decay.

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Takeshi Yamazaki, Ken-ichi Ishikawa, Naruhito Ishizuka, Yoshinobu Kuramashi, Yusuke Namekawa, Yusuke Taniguchi, Naoya Ukita, Tomoteru Yoshié for PACS Collaboration. 2023-11-28. $|V_{us}|$ from kaon semileptonic form factor in $N_f = 2+1$ QCD at the physical point on (10 fm)$^4$. https://arxiv.org/abs/2311.16755

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