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Reconstruction of smeared spectral function from Euclidean correlation functions

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 نشر من قبل Shoji Hashimoto
 تاريخ النشر 2020
  مجال البحث
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We propose a method to reconstruct smeared spectral functions from two-point correlation functions measured on the Euclidean lattice. Arbitrary smearing function can be considered as far as it is smooth enough to allow an approximation using Chebyshev polynomials. We test the method with numerical lattice data of Charmonium correlators. The method provides a framework to compare lattice calculation with experimental data including excited state contributions without assuming quark-hadron duality.

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