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arXiv · 1110.0319

Rummukainen-Gottlieb's formula on two-particle system with different mass

Ziwen Fu
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Abstract

Lüscher established a non-perturbative formula to extract the elastic scattering phases from two-particle energy spectrum in a torus using lattice simulations. Rummukainen and Gottlieb further extend it to the moving frame, which is devoted to the system of two identical particles. In this work, we generalize Rummukainen-Gottlieb's formula to the generic two-particle system where two particles are explicitly distinguishable, namely, the masses of the two particles are different. The finite size formula are achieved for both $C_{4v}$ and $C_{2v}$ symmetries. Our analytical results will be very helpful for the study of some resonances, such as kappa, vector kaon, and so on.

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Ziwen Fu. 2012-06-09. Rummukainen-Gottlieb's formula on two-particle system with different mass. https://doi.org/10.1103/physrevd.85.014506

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