# 36th Annual International Symposium on Lattice Field Theory

Jul 22 – 28, 2018
Kellogg Hotel and Conference Center
EST timezone

## Semileptonic decays of $B_{(s)}$ mesons to light pseudoscalar mesons on four-flavor HISQ ensembles

Jul 27, 2018, 5:10 PM
20m
103 (Kellogg Hotel and Conference Center)

### 103

#### Kellogg Hotel and Conference Center

219 S Harrison Rd, East Lansing, MI 48824
Weak Decays and Matrix Elements

### Speaker

Mr Zechariah Gelzer (University of Iowa)

### Description

We report the status of an ongoing lattice-QCD calculation of form factors for exclusive semileptonic decays of $B$~mesons with both charged currents ($B\to\pi\ell\nu$, $B_s\to K\ell\nu$) and neutral currents ($B\to\pi\ell^+\ell^-$, $B\to K\ell^+\ell^-$). The results are important for constraining or revealing physics beyond the Standard Model. This work uses MILC's (2+1+1)-flavor ensembles with the HISQ action for the sea and light valence quarks and the clover action in the Fermilab interpretation for the $b$~quark. Simulations are carried out at three lattice spacings down to $0.088$~fm, with both physical and unphysical sea-quark masses. We present preliminary blinded results for the form factors $f_+(q^2)$, $f_0(q^2)$, and $f_T(q^2)$ (in terms of momentum transfer $q^2$), along with an examination of systematic errors. Our preliminary results include studies of $z$-expansion methods to extend the kinematic range.

### Primary author

Mr Zechariah Gelzer (University of Iowa)

### Co-authors

Prof. Aida El-Khadra (University of Illinois at Urbana-Champaign) Dr Andreas Kronfeld (Fermilab) Carleton DeTar (University of Utah) Prof. Claude Bernard (Washington University) Dr Elvira Gamiz (University of Granada) Dr James Simone (Fermilab) Dr Ruth Van de Water (Fermilab) Steven Gottlieb (Indiana Univ.) Yannick Meurice (U. of Iowa)

 Slides