### Impacto

### Downloads

Downloads per month over past year

Peláez Sagredo, José Ramón and Rios, G.
(2010)
*Chiral extrapolation of light resonances from one and two-loop unitarized chiral perturbation theory versus lattice results.*
Physical review D, 82
(11).
ISSN 1550-7998

Preview |
PDF
456kB |

Official URL: http://dx.doi.org/10.1103/PhysRevD.82.114002

## Abstract

We study the pion mass dependence of the ρ(770) and f_0(600) masses and widths from one and two-loop unitarized chiral perturbation theory ( ChPT). We show the consistency of one-loop calculations with lattice results for the M_ρ, f_π and the isospin-2 scattering length a-20. Then, we develop and apply the modified inverse amplitude method formalism for two-loop ChPT. In contrast to the f_0(600), the ρ(770) is rather sensitive to the two-loop ChPT parameters-our main source of systematic uncertainty. We thus provide two-loop unitarized fits constrained by lattice information on M_ρ, f_π, by the q q̅ leading 1/N_c behavior of the ρ and by existing estimates of low-energy constants. These fits yield relatively stable predictions up to m_π ̴̲ 300-350 MeV for the rho coupling and width as well as for all the f_0(600) parameters. We confirm, to two loops, the weak m_π dependence of the rho coupling and the Kawarabayashi-Suzuki-Riazuddin-Fayyazuddin relation, and the existence of two virtual f_0(600) poles for sufficiently high m_π. At two loops one of these poles becomes a bound state when m_π is somewhat larger than 300 MeV.

Item Type: | Article |
---|---|

Additional Information: | ©2010 The American Physical Society. |

Uncontrolled Keywords: | Pi-pi scattering; Scalar mesons; Gev-c; Dispersion-relations; High statistics; Form-factors; Low-energy; One-loop; Sigma; Lagrangians |

Subjects: | Sciences > Physics > Physics-Mathematical models Sciences > Physics > Mathematical physics |

ID Code: | 35071 |

Deposited On: | 19 Jan 2016 17:30 |

Last Modified: | 10 Dec 2018 15:09 |

### Origin of downloads

Repository Staff Only: item control page