RT Journal Article T1 Study of χb meson production in p p collisions at √s=7 and 8TeV and observation of the decay χb(3P)→Υ(3S)γ A1 LHCb Collaboration, A1 Adeva Andany, Bernardo A1 Álvarez Cartelle, Paula A1 Dosil Suárez, Álvaro A1 Fernández Albor, Víctor Manuel A1 Gallas Torreira, Abraham Antonio A1 García Pardiñas, Julián A1 Hernando Morata, José Ángel A1 Pazos Álvarez, Antonio A1 Pérez Trigo, Eliseo A1 Plo Casasus, Máximo A1 Romero Vidal, Antonio A1 Saborido Silva, Juan José A1 Sanmartín Sedes, Brais A1 Santamarina Ríos, Cibrán A1 Seco Miguélez, Marcos Antonio A1 Vázquez Regueiro, Pablo A1 Vázquez Sierra, Carlos A1 Vieites Díaz, María AB A study of χb meson production at LHCb is performed on proton–proton collision data, corresponding to 3.0 fb−1of integrated luminosity collected at centre-of-mass energies √s= 7 and 8 TeV. The fraction of Υ(nS) mesons originating from χb decays is measured as a function of the Υ transverse momentum in the rapidity range 2.0