Vector Boson Scattering at High Mass with ATLAS

In the absence of a light Higgs boson, the mechanism of electroweak symmetry breaking will be best studied in processes of vector boson scattering at high mass. Various models predict resonances in this channel. Scalar and vector resonances have been investigated in the WW, WZ and ZZ channels.The ability of ATLAS to measure the di-boson cross- section over a range of centre-of- mass energies will be shown. Particular attention will be paid to the jet pairs reconstruction with low opening angle resulting from the decays of highly boosted vector bosons; the performance of different jet algorithms will be compared.