This collaborative project is in the area of Elementary Particle Physics Phenomenology, with focus on some extensions of the Standard Model (SM) of Particle Physics and top quark physics. It brings together theoretical and experimental particle physicists. The proposed collaboration is a research programme where the applicant's expertise on the theoretical aspects of nonstandardHiggs production and the search of new physics in top quark production and decay in proton-proton collisions is matched with the expertise at the host institution as a part of the European network the applicant is building.We are especially interested in the search for the Higgs boson, the last particle (or particles) of the SM, that still remains to be experimentally discovered. The Higgs boson is potentially the key to answer the fundamental mystery of why elementary particles have mass. Its search is therefore the primary goal for CERN's Large Hadron Collider. New physics can also be hidden in the top quark, the heaviest of all known fermions. Our main goal is to contribute to a better understanding of the world of particle physics, by proposing theoretical models in the above area and developing and optimizing tools and data analysis techniques to experimentally detect their signatures.The expertise and skills of the the parties in this proposed collaboration (where not only the host institution takes part but also other institutions in Portugal and in the UK) match and complement each other extremely well. Exploring this synergy will produce a very fruitful collaboration, mutually advantageous to both parties. This application is ideally timed, as the data taking phase of ATLAS and the LHC has started at a centre-of-mass energy of 7 TeV and it will resume operation in 2013 with the planned 14 TeV stage.