New physics from the top at the LHC Authors Chien-Yi Chen Department of Physics Carnegie Mellon University Ayres Freitas PITTsburgh Particle physics, Astrophysics, and Cosmology Center (PITT PACC), Department of Physics & Astronomy University of Pittsburgh Tao Han PITTsburgh Particle physics, Astrophysics, and Cosmology Center (PITT PACC), Department of Physics & Astronomy University of Pittsburgh Keith S. M. Lee PITTsburgh Particle physics, Astrophysics, and Cosmology Center (PITT PACC), Department of Physics & Astronomy University of Pittsburgh Article

First Online: 21 November 2012 Received: 30 July 2012 Revised: 15 October 2012 Accepted: 20 October 2012 DOI :
10.1007/JHEP11(2012)124

Cite this article as: Chen, C., Freitas, A., Han, T. et al. J. High Energ. Phys. (2012) 2012: 124. doi:10.1007/JHEP11(2012)124
Abstract The top quark may hold the key to new physics associated with the electroweak symmetry-breaking sector, given its large mass and enhanced coupling to the Higgs sector. We systematically categorize generic interactions of a new particle that couples to the top quark and a neutral particle, which is assumed to be heavy and stable, thus serving as a candidate for cold dark matter. The experimental signatures for new physics involving top quarks and its partners at the Large Hadron Collider (LHC) may be distinctive, yet challenging to disentangle. We optimize the search strategy at the LHC for the decay of the new particle to a top quark plus missing energy and propose the study of its properties, such as its spin and couplings. We find that, at 14 TeV with an integrated luminosity of 100 fb^{−1} , a spin-zero top partner can be observed at the 5σ level for a mass of 675 GeV. A spin-zero particle can be differentiated from spin-1/2 and spin-1 particles at the 5σ level with a luminosity of 10 fb^{−1} .

Keywords Supersymmetry Phenomenology Phenomenology of Field Theories in Higher Dimensions

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