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arXiv · 1812.07675

Update on $B\to D^\ast \ell \nu$ form factor at zero-recoil using the Oktay-Kronfeld action

Tanmoy Bhattacharya·Rajan Gupta·Sungwoo Park·Yong-Chull Jang·Jon A. Bailey·Benjamin J. Choi·Hwancheol Jeong·Seungyeob Jwa·Sunkyu Lee·Weonjong Lee·Jeonghwan Pak·Jaehoon Leem
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Abstract

We present an update on the calculation of $\bar{B}\to D^\ast \ell \bar{\nu}$ semileptonic form factor at zero recoil using the Oktay-Kronfeld bottom and charm quarks on $N_f=2+1+1$ flavor HISQ ensembles generated by the MILC collaboration. Preliminary results are given for two ensembles with $a\approx 0.12$ and $0.09$ fm and $M_\pi\approx 310$ MeV. Calculations have been done with a number of valence quark masses, and the dependence of the form factor on them is investigated on the $a\approx 0.12$ fm ensemble. The excited state is controlled by using multistate fits to the three-point correlators measured at 4--6 source-sink separations.

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Tanmoy Bhattacharya, Rajan Gupta, Sungwoo Park, Yong-Chull Jang, Jon A. Bailey, Benjamin J. Choi, Hwancheol Jeong, Seungyeob Jwa, Sunkyu Lee, Weonjong Lee, Jeonghwan Pak, Jaehoon Leem. 2018-12-18. Update on $B\to D^\ast \ell \nu$ form factor at zero-recoil using the Oktay-Kronfeld action. https://doi.org/10.22323/1.334.0283

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