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arXiv · 1911.04282

$B_c \to B_{s(d)}$ form factors

Laurence Cooper·Matthew Wingate·Christine Davies·Judd Harrison·Javad Komijani
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Abstract

We present results of the first lattice QCD calculations of $B_c \to B_s$ and $B_c \to B_d$ weak matrix elements. Results are derived from correlation functions computed on MILC Collaboration gauge configurations with lattice spacings between $0.12$ [fm] and $0.06$ [fm] including 2+1+1 flavours of dynamical sea quarks in the Highly Improved Staggered Quark (HISQ) formalism. Form factors across the entire physical $q^2$ range are then extracted and extrapolated to the physical-continuum limit. Two different formalisms are employed for the bottom quark: non-relativistic QCD (NRQCD) and heavy-HISQ. Checking agreement between these two approaches is an important test of our strategies for heavy quarks on the lattice.

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Laurence Cooper, Matthew Wingate, Christine Davies, Judd Harrison, Javad Komijani. 2019-11-11. $B_c \to B_{s(d)}$ form factors. https://arxiv.org/abs/1911.04282

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