Eur. Phys. J. A (2020) 56: 294
https://doi.org/10.1140/epja/s10050-020-00300-y

Regular Article – Theoretical Physics

Open-charm Euclidean correlators within heavy-meson EFT interactions

¹ Departament de Física Quàntica i Astrofísica and Institut de Ciències del Cosmos(ICCUB), Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, 08028, Barcelona, Spain
² Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, 430079, Wuhan, China
³ Fakultät für Physik, Universität Bielefeld, 33615, Bielefeld, Germany
⁴ Institut für Theoretische Physik, Goethe Universität Frankfurt, Max von Laue Strasse 1, 60438, Frankfurt am Main, Germany
⁵ Frankfurt Institute for Advanced Studies, Ruth-Moufang-Str. 1, 60438, Frankfurt am Main, Germany
⁶ Institute of Space Sciences (ICE, CSIC), Campus UAB, Carrer de Can Magrans, 08193, Barcelona, Spain
⁷ Institut d’Estudis Espacials de Catalunya (IEEC), 08034, Barcelona, Spain

^a gmontana@fqa.ub.edu

Received: 30 July 2020
Accepted: 7 November 2020
Published online: 20 November 2020

Abstract

The open-charm Euclidean correlators have been computed for the first time using the thermal spectral functions extracted from a finite-temperature self-consistent unitarized approach based on a chiral effective field theory that implements heavy-quark spin symmetry. The inclusion of the full-energy dependent open-charm spectral functions in the calculation of the Euclidean correlators leads to a similar behaviour as the one obtained in lattice QCD for temperatures well below the transition deconfinement temperature. The discrepancies at temperatures close or above the transition deconfinement temperature could indicate that higher-energy states, that are not present in the open-charm spectral functions, become relevant for a quantitative description of the lattice QCD correlators at those temperatures. In fact, we find that the inclusion of a continuum of scattering states improves the comparison at small Euclidean times, whereas differences still arise for large times.