RT Book, Section T1 Regge trajectories of ordinary and non-ordinary mesons from their scattering poles. A1 Nebreda Manjón, Jenifer A1 Carrasco, J. A. A1 Londergan, J. T. A1 Peláez Sagredo, José Ramón A1 Szczepaniak, Adam P. AB Our results on obtaining the Regge trajectory of a resonance from its pole in a scattering process and from analytic constraints in the complex angular momentum plane are presented. The method, suited for resonances that dominate an elastic scattering amplitude, has been applied to the ρ(770), ƒ_2(1270), ƒ_2(1525) and ƒ_0(500) resonances. Whereas for the first three we obtain linear Regge trajectories, characteristic of ordinary quark-antiquark states, for the latter we find a non-linear trajectory with a much smaller slope at the resonance mass. We also show that if a linear trajectory with a slope of typical size is imposed for the ƒ_0(500), the corresponding amplitude is at odds with the data. This provides a strong indication of the non-ordinary nature of the sigma meson. PB American Institute of Physics AIP SN 978-0-7354-1348-1 YR 2016 FD 2016 LK https://hdl.handle.net/20.500.14352/24870 UL https://hdl.handle.net/20.500.14352/24870 LA eng NO © 2016 AIP Publishing LLC.Conference on Quark Confinement and Hadron Spectrum (11ª. 2014. San Petersburgo, Rusia).J.N. wants to thank the organizers of the conference for giving her the opportunity to present this work. J.R.P. and J.N. are supported by the Spanish project FPA2011-27853-C02-02. JN acknowledges funding by the Deutscher Akademischer Austauschdienst (DAAD), the Fundación Ramón Areces and the hospitality of Bonn and Indiana Universities. A.P.S is supported in part by the U.S. Department of Energy under Grant DE-FG0287ER40365. J.T.L. is supported by the U.S. National Science Foundation under grant PHY-1205019. NO Ministerio de Economía y Competitividad (MINECO) NO Deutscher Akademischer Austauschdienst (DAAD), Alemania NO Fundación Ramón Areces NO U.S. Department of Energy NO U.S. National Science Foundation (NSF) DS Docta Complutense RD 13 abr 2025