Proceedings of 5th International Workshop on Top Quark Physics (TOP2012)

The 5th International Workshop on Top Quark Physics (TOP 2012) took place in Winchester, UK, from the 16–21 September. It gathered students as well as people active in the top quark sector and provided a framework to highlight the newest results and matters related to top quark physics. Discovered in 1995, the top quark is the sixth and heaviest of all quarks, and it is the only one with a lifetime short enough to be observed 'naked'. This makes it an important testing ground in the search for new physics. In fact, the fact of its mass being so much larger than the other quarks, hints at its special role in the Higgs mechanism. For the same reason, in many models of New Physics, new heavy resonances are expected to couple mostly with top quarks. Even if no new particles are observed, the direct correlation between its angular momentum and that of its detectable decay products allows us to probe indirectly New Physics in action when top quarks are created.In this edition of the TOP conference series, for the first time, the agenda was equally balanced between 'traditional' measurements and the now vast number of searches for physics BSM in the top quark sector, thanks mostly to the amount of data collected at the LHC in its Run I. New results were presented by both the Tevatron and the LHC collaborations: improved ttbar and single top cross-section measurements, refined techniques to measure the top quark mass and a large number of results on properties such as spin correlation and W boson polarization in top quark decays were shown. More technical discussions on the experimental issues, both from the detector and the simulation side also took place, drawing together experimentalists and theorists. Reviews of the latest results on ttbar asymmetry both from CDF and D0 and from ATLAS and CMS were shown, and theorists active in the field made some interesting points on this hot topic. Additionally, results on the search for fourth generation fermions and new resonances in the boosted top regime were also provided. Finally, a set of dedicated talks on the interplay between the top sector and other hot subjects, like the Higgs and SUSY, were given both at the theory and experimental level.Furthermore, ad hoc student sessions were organized to allow younger colleagues to pose questions to the senior experts in the field and contribute with their more recent studies.The conference has been a definitive success, not just scientifically: about 130 participants from all over the world created a collegiate spirit which culminated in the social events at Winchester Hall below King Arthur's table; and in a cosy 16th century barn for the social dinner.The Local Organizing Committee would like to thank all participants, and in particular the speakers, for their high level contributions to TOP 2012 and for making this a very fruitful and pleasant time together.We conclude by wishing the Organizing Committee of TOP 2013 all the best for a successful conference. We look forward to seeing everyone in Germany in 2013