RT Journal Article T1 Light scalars as tetraquarks or two-meson states from large N_c and unitarized Chiral Perturbation Theory A1 Peláez Sagredo, José Ramón AB By means of unitarized Chiral Perturbation Theory it is possible to obtain a remarkable description of meson-meson scattering amplitudes up to 1.2 GeV, and generate poles associated to scalar and vector resonances. Since Chiral Perturbation Theory is the QCD low energy effective theory, it is then possible to study its large N_c limit where q q̅ states are easily identified. The vectors thus generated follow closely a q q̅ behavior, whereas the light scalar poles follow the large-N-c behavior expected for a dominant tetraquark or two-meson structure. PB World Scientific Publ Co Pte Ltd SN 0217-7323 YR 2004 FD 2004-12-21 LK https://hdl.handle.net/20.500.14352/51732 UL https://hdl.handle.net/20.500.14352/51732 LA eng NO ©World Scientific Publ Co Pte Ltd.I thank A. Andrianov, D. Espriu, A. Gómez Nicola, F. Kleefeld, R. Jaffe, E. Oset, J. Soto and M. Uehara for their comments and support from the Spanish CICYT projects, BFM2000-1326, BFM2002-01003 and the E.U. EURIDICE network contract no. HPRN-CT-2002-00311. NO Spanish CICYT NO E.U. EURIDICE network DS Docta Complutense RD 1 ene 2026