Measurement of the cross-section ratio sigma(chi(c2))/sigma(chi(c1)) for prompt chi(c) production at root s=7 TeV LHCb Collaboration by Aaij, R, Abelian Beteta, C, Adeva, B, Adinolfi, M, Adrover, C, Affolder, A, Ajaltouni, Z, Albrecht, J, Alessio, F, Alexander, M, Alkhazov, G, Alvarez Cartelle, P, Jr, A, Amato, S, Amhis, Y, Anderson, J, Appleby, R, Gutierrez, O, Archilli, F, Arrabito, L, Artamonov, A, Artuso, M, Aslanides, E, Auriemma, G, Bachmann, S