Affiliation: | Isaac Newton Group, Apartado de Correos 321, 38700 Santa Cruz de La Palma, Canary Islands, Spain;Centre for Astrophysics, University of Central Lancashire, Preston PR1 2HE;Computational Astrophysics, Department of Computing, University of Central Lancashire, Preston PR1 2HE;Observatorio Astronómico Cerro Calán, Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile |