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Exotic Signals of Vectorlike Quarks

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 نشر من قبل Felix Yu
 تاريخ النشر 2016
  مجال البحث
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Vectorlike fermions are an important target for hadron collider searches. We show that the vectorlike quarks may predominantly decay via higher-dimensional operators into a quark plus a couple of other Standard Model fermions. Pair production of vectorlike quarks of charge 2/3 at the LHC would then lead to a variety of possible final states, including $tbar t + 4tau$, $tbar b u + 3tau$, $tbar t + 4mu$, $tbar b u + 3mu$ or $tbar t + 4b$. Additional channels ($bbar b + 4tau$, $6b$, etc.) arise in the case of a vectorlike quark of charge $-1/3$. If the vectorlike quark decays into three light quarks, then the $(3j)(3j)$ signal is more difficult to observe, and the vectorlike quark mass is almost unconstrained by current searches.



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