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A new class of SUSY signatures in the processes $gg to HH, ~VH$

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 Added by Georgios Gounaris
 Publication date 2009
  fields
and research's language is English




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Within the MSSM and SM frameworks, we analyze the 1loop electroweak (EW) predictions for the helicity amplitudes describing the 17 processes $ggto HH$, and the 9 processes $ggto VH$; where $H,H$ denote Higgs or Goldstone bosons, while $V= Z, ~W^pm$. Concentrating on MSSM, we then investigate how the asymptotic helicity conservation (HCns) property of SUSY, affects the amplitudes at the LHC energy range; and what is the corresponding situation in SM, where no HCns theorem exists. HCns is subsequently used to construct many relations among the cross sections of the above MSSM processes, depending only on the angles $alpha$ and $beta$. These relations should be asymptotically exact, but with mass-depending deviations appearing, as the energy decreases towards the LHC range. Provided the SUSY scale is not too high, they may remain roughly correct, even at the LHC energy range.



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We study how the property of asymptotic helicity conservation (HCns), expected for any 2-to-2 process in the minimal supersymmetric model (MSSM), is realized in the processes $gg to gammagamma,gamma Z,ZZ,W^+W^-$, at the 1loop electroweak order and very high energies. The violation of this property for the same process in the standard model (SM), is also shown. This strengthens the claim that HCns is specific to the renormalizable SUSY model, and not generally valid in SM. HCns strongly reduces the number of non-vanishing 2-to-2 amplitudes at asymptotic energies in MSSM. Consequences at LHC and higher energy colliders are identified.
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