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Article
Report number	arXiv:2312.09811 ; HU-EP-23/71 ; DESY-23-216 ; MS-TP-23-53
Title	A strategy for B-physics observables in the continuum limit
Author(s)	Sommer, Rainer (DESY, Zeuthen ; Humboldt U., Berlin) ; Conigli, Alessandro (CSIC, Madrid ; Helmholtz Inst., Mainz ; Darmstadt, GSI) ; Frison, Julien (DESY, Zeuthen) ; Fritzsch, Patrick (TCD, Dublin) ; Gérardin, Antoine (Marseille, CPT) ; Heitger, Jochen (U. Munster) ; Herdoiza, Gregorio (CSIC, Madrid) ; Kuberski, Simon (CERN ; Helmholtz Inst., Mainz ; Darmstadt, GSI) ; Pena, Carlos (CSIC, Madrid) ; Simma, Hubert (DESY, Zeuthen)
Publication	2024-05-07
Imprint	2023-12-15
Number of pages	10
Note	Lattice 2023 talk
In:	PoS LATTICE2023 (2024) 268
In:	40th International Symposium on Lattice Field Theory (Lattice 2023), Fermilab, Batavia, IL, United States, 30 Jul - 5 Aug 2023, pp.268
DOI	10.22323/1.453.0268
Subject category	hep-ph ; Particle Physics - Phenomenology ; hep-lat ; Particle Physics - Lattice
Abstract	In a somewhat forgotten paper [1] it was shown how to perform interpolations between relativistic and static computations in order to obtain results for heavy-light observables for masses from, say, $m_{\rm charm}$ to $m_{\rm bottom}$. All quantities are first continuum extrapolated and then interpolated in $1/m_h=1/m_{\rm heavy}$. Large volume computations are combined with finite volume ones where a relativistic bottom quark is accessible with small $am_{\rm bottom}$. We discuss how this strategy is extended to semi-leptonic form factors and other quantities of phenomenological interest. The essential point is to form quantities where the limit $m_h\to\infty$ is approached with power corrections O$(1/m_h)$ only. Perturbative corrections $\sim\alpha_s(m_h)^{\gamma+n}$ are cancelled in the construction of the observables. We also point out how such an approach can help to control systematics in semi-leptonic decays with just large volume data. First numerical results with $N_f = 2 + 1$ and lattice spacings down to 0.039 fm are presented in [2].
Copyright/License	publication: © 2024-2025 The author(s) (License: CC-BY-NC-ND-4.0) preprint: (License: CC BY 4.0)

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