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arXiv · 0707.2030

On the definition of the Δmass and width

D. Djukanovic·J. Gegelia·S. Scherer
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Abstract

In the framework of effective field theory we show that, at two-loop order, the mass and width of the Δresonance defined via the (relativistic) Breit-Wigner parametrization both depend on the choice of field variables. In contrast, the complex-valued position of the pole of the propagator is independent of this choice.

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D. Djukanovic, J. Gegelia, S. Scherer. 2007-07-13. On the definition of the Δmass and width. https://doi.org/10.1103/physrevd.76.037501

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