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arXiv · 2205.11564

Optimising creation operators for charmonium spectroscopy on the lattice

Francesco Knechtli·Tomasz Korzec·Michael Peardon·Juan Andrés Urrea-Niño
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Abstract

Smearing the bare quantum fields in lattice calculations before applying composite hadron creation operators has a long record of substantially improving overlaps onto low-lying energy eigenstates. A technique called distillation which defines smearing for quark fields as a low-rank linear projection operator into a small vector space of smooth gauge-covariant fields has proven to be both effective and versatile in hadron spectroscopy calculations albeit with significant computational cost . In this paper, more general operators in this space of smooth fields are introduced and optimised, which enhances the performance of the method when tested on systems of heavy quark-anti-quark pairs close to the charmonium energy scale.

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Francesco Knechtli, Tomasz Korzec, Michael Peardon, Juan Andrés Urrea-Niño. 2022-05-23. Optimising creation operators for charmonium spectroscopy on the lattice. https://doi.org/10.1103/physrevd.106.034501

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