[1] Univ Catolica Norte, Dept Fis, Ave Angamos 0610,Casilla 1280, Antofagasta, Chile
[2] Univ Tecn Federico Santa Maria, Casilla 110-V, Valparaiso, Chile
[3] Ctr Cient Tecnol Valparaiso, Casilla 110-V, Valparaiso, Chile
[4] Millennium Inst Subatom Phys High Energy Frontier, Fernandez Concha 700, Santiago, Chile
[5] Univ Andres Bello, Fac Ciencias Exactas, Ctr Theoret & Expt Particle Phys, Fernandez Concha 700, Santiago, Chile
[6] Univ Clermont Auvergne, Lab Phys Clermont, UMR 6533, CNRS,IN2P3, 4 Ave Blaise Pascal, F-63178 Aubiere, France
[7] Lund Univ, Dept Phys, SE-22100 Lund, Sweden
[8] Univ Tecn Federico Santa Maria, Dept Fis, Casilla 110-V, Valparaiso, Chile