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The other Higgses, at resonance, in the Lee-Wick extension of the Standard Model

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 نشر من قبل Terrance Figy
 تاريخ النشر 2011
  مجال البحث
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Within the framework of the Lee Wick Standard Model (LWSM) we investigate Higgs pair production $gg to h_0 h_0$, $gg to h_0 tilde p_0$ and top pair production $gg to bar tt$ at the Large Hadron Collider (LHC), where the neutral particles from the Higgs sector ($h_0$, $tilde h_0$ and $tilde p_0$) appear as possible resonant intermediate states. We investigate the signal $gg to h_0 h_0 to bar b b gamma gamma$ and we find that the LW Higgs, depending on its mass-range, can be seen not long after the LHC upgrade in 2012. More precisely this happens when the new LW Higgs states are below the top pair threshold. In $gg to bar tt$ the LW states, due to the wrong-sign propagator and negative width, lead to a dip-peak structure instead of the usual peak-dip structure which gives a characteristic signal especially for low-lying LW Higgs states. We comment on the LWSM and the forward-backward asymmetry in view of the measurement at the TeVatron. Furthermore, we present a technique which reduces the hyperbolic diagonalization to standard diagonalization methods. We clarify issues of spurious phases in the Yukawa sector.

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