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arXiv · 1911.02412

Heavy semileptonics with a fully relativistic mixed action

Julien Frison·Andrea Bussone·Gregorio Herdoíza·Carlos Pena·Jose Ángel Romero·Javier Ugarrio
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Abstract

The first phase of a heavy quark program based on twisted mass valence quarks has been presented at last years's lattice conference. The CLS $N_f=2+1$ ensembles were used for their fine lattice spacing, while twisting the masses is expected to reduce discretisation errors even further and allow for a fully relativistic calculation. We present our strategy and preliminary results on three point functions, corresponding to $D\to K$ and $D\to\pi$ semileptonic decays. The form factors for $m_u=m_d=m_s$ quark masses obtained as a first step are shown here to be at the percent level in statistical precision at $q^2=0$.

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Julien Frison, Andrea Bussone, Gregorio Herdoíza, Carlos Pena, Jose Ángel Romero, Javier Ugarrio. 2019-11-06. Heavy semileptonics with a fully relativistic mixed action. https://arxiv.org/abs/1911.02412

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