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arXiv · 1101.3844

Searches for the $t^\prime$ of a fourth family

Bob Holdom·Qi-Shu Yan
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Abstract

We study the detection of the $t^\prime$ of a fourth family during the early running of LHC with 7 TeV collision energy and 1 fb$^{-1}$ integrated luminosity. By use of a neural network we show that it is feasible to search for the $t'$ even with a mass close to the unitarity upper bound, which is in the 500 to 600 GeV range. We also present results for the Tevatron with $10 \,\, \textrm{fb}^{-1}$. In both cases the search for a fourth family quark doublet can be significantly enhanced if one incorporates the contribution that the $b'$ can make to a $t'$-like signal. Thus the bound on the mass of a degenerate quark doublet should be stronger than the bounds obtained by treating $t'$ and $b'$ in isolation.

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Bob Holdom, Qi-Shu Yan. 2011-06-20. Searches for the $t^\prime$ of a fourth family. https://doi.org/10.1103/physrevd.83.114031

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