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Extraction of the resonance parameters at finite times

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 نشر من قبل Kathryn Polejaeva
 تاريخ النشر 2010
  مجال البحث
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 تأليف Ulf-G. Mei{ss}ner




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In this paper we propose a model-independent method to extract the resonance parameters on the lattice directly from the Euclidean 2-point correlation functions of the field operators at finite times. The method is tested in case of the two-point function of the Delta-resonance, calculated at one loop in Small Scale Expansion. Further, the method is applied to a 1+1-dimensional model with two coupled Ising spins and the results are compared with earlier ones obtained by using Lueschers approach.

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