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Phenomenological Constraints on Extra-Dimensional Scalars

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 نشر من قبل Pierre-Hugues Beauchemin
 تاريخ النشر 2004
  مجال البحث
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We examine whether the ATLAS detector has sensitivity to extra-dimensional scalars (as opposed to components of higher-dimensional tensors which look like 4D scalars), in scenarios having the extra-dimensional Planck scale in the TeV range and $n ge 2$ nonwarped extra dimensions. Such scalars appear as partners of the graviton in virtually all higher-dimensional supersymmetric theories. Using the scalars lowest-dimensional effective couplings to quarks and gluons, we compute the rate for the production of a hard jet together with missing energy. We find a nontrivial range of graviscalar couplings to which ATLAS could be sensitive, with experiments being more sensitive to couplings to gluons than to quarks. Graviscalar emission increases the missing-energy signal by adding to graviton production, and so complicates the inference of the extra-dimensional Planck scale from an observed rate. Because graviscalar differential cross sections resemble those for gravitons, it is unlikely that these can be experimentally distinguished from one another should a missing energy signal be observed.



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