# W-Jet Tagging: Optimizing the Identification of Boosted Hadronically-Decaying W Bosons

 Title: W-Jet Tagging: Optimizing the Identification of Boosted Hadronically-Decaying W Bosons Author: Cui, Yanou; Han, Zhenyu; Schwartz, Matthew D Note: Order does not necessarily reflect citation order of authors. Citation: Cui, Yanou, Zhenyu Han, and Matthew D. Schwartz. 2011. W-jet tagging: optimizing the identification of boosted hadronically-decaying W bosons. Physical Review D 83(7): 074023. Full Text & Related Files: W-jet Tagging.pdf (2.594Mb; PDF) Abstract: A method is proposed for distinguishing highly boosted hadronically-decaying $$W's$$ $$(W jets)$$ from QCD-jets using jet substructure. Previous methods, such as the filtering/mass-drop method, can give a factor of $$\sim 2$$ improvement in $$S/\sqrt{B}$$ for jet $$p_T \ge 200 GeV$$. In contrast, a multivariate approach including new discriminants such as $$R$$ cores, which characterize the shape of the $$W$$ jet, subjet planar flow, and grooming-sensitivities is shown to provide a much larger factor of $$\sim 5$$ improvement in $$S/\sqrt{B}$$. For longitudinally polarized $$W's$$, such as those coming from many new physics models, the discrimination is even better. Comparing different Monte Carlo simulations, we observe a sensitivity of some variables to the underlying event; however, even with a conservative estimates, the multivariate approach is very powerful. Applications to semileptonic $$WW$$ resonance searches and all-hadronic $$W+jet$$ searches at the LHC are also discussed. Code implementing our $$W-je$$t tagging algorithm is publicly available at http://jets.physics.harvard.edu/wtag. Published Version: 10.1103/PhysRevD.83.074023 Other Sources: http://arxiv.org/abs/1012.2077 Terms of Use: This article is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#OAP Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:8063806

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Peer reviewed scholarly articles from the Faculty of Arts and Sciences of Harvard University