High mass resonances decaying into ttbar pairs appear in many extensions of
the Standard Model. The top quarks from these decays have high transverse
momenta and their decay products are highly collimated due to the boost into
the lab frame. As a result the standard techniques for reconstructing ttbar
events begin to fail. In this talk we discuss the prospects for detecting
booted top quarks at CMS. A new top jet tagging algorithm is presented. This
algorithm achieves an efficiency of 46% for boosted top jets and rejection of
98.5% for generic QCD jets with transverse momenta of 600 GeV/c.Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July
2009, eConf C09072