TY - JOUR

T1 - Some remarks on the Padé unitarization of low-energy amplitudes

AU - Masjuan, P.

AU - Sanz-Cillero, J. J.

AU - Virto, J.

PY - 2008/9/25

Y1 - 2008/9/25

N2 - We present a critical analysis of Padé-based methods for the unitarization of low energy amplitudes. We show that the use of certain Padé approximants to describe the resonance region may lead to inaccurate determinations. In particular, we find that in the (weakly coupled) Linear Sigma Model the unitarization of the low energy amplitude through the inverse amplitude method does not recover the correct values for the mass and width of the sigma. Alternative sequences of Padés are studied and we find that the diagonal sequences (i.e., [N / N]) have much better convergence properties. © 2008 Elsevier B.V. All rights reserved.

AB - We present a critical analysis of Padé-based methods for the unitarization of low energy amplitudes. We show that the use of certain Padé approximants to describe the resonance region may lead to inaccurate determinations. In particular, we find that in the (weakly coupled) Linear Sigma Model the unitarization of the low energy amplitude through the inverse amplitude method does not recover the correct values for the mass and width of the sigma. Alternative sequences of Padés are studied and we find that the diagonal sequences (i.e., [N / N]) have much better convergence properties. © 2008 Elsevier B.V. All rights reserved.

U2 - 10.1016/j.physletb.2008.07.106

DO - 10.1016/j.physletb.2008.07.106

M3 - Article

VL - 668

SP - 14

EP - 19

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

IS - 1

ER -