PECULIJETS · Establishing Precision and Controlling Uncertainties for Multijet Simulations at the LHC

As the Large Hadron Collider probes nature with unprecedented energiesand luminosity it is vital to have accurate simulations which can becompared directly with data. This involves incorporating exactcalculations at a fixed order in the perturbative expansion with theapproximate calculations normally used in simulations of high energycollisions.The PECULIJETS project will develop such simulations by concentratingon the accurate simulation of processes involving photons. Theseprocesses are important both in their own right and as the backgroundsto both the production of the Higgs boson and the search for newphysics beyond the Standard Model. They are an essential component aswe strive for more and more accurate simulations, occurring atapproximately the same rate as the second order corrections in thestrong coupling and forming a vital part of the full higher orderelectroweak corrections.The project will achieve this through: the development of state of theart simulations of the production of a photon in association with oneor two jets at next-to-leading order (NLO) in the strong couplingconstant (WP1); matching in the case that there are bothelectromagnetic and strong corrections, for example dijet production(WP2); improving multijet merging techniques using the high energyjets formalism, with particular emphasis on assessing theuncertainties involved in such approaches (WP3); incorporating bothelectromagnetic and strong radiation in multijet merging. All ofthese objectives build upon each other and will lead to astate-of-the-art simulation of processes involving bothelectromagnetic and strong corrections. The new simulations will beincorporated with the Herwig++ simulation package so that they caneasily be used by the LHC experiments in their analyses and to compareour theoretical predictions and the latest experimental results.