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Spin effects in the antler event topology at hadron colliders

  • Lisa Edelhäuser
  • Konstantin T. Matchev
  • Myeonghun Park
Open Access
Article

Abstract

We investigate spin correlation effects in the “antler” event topology ppA(A*) → B 1 B 2 → ( C 1)( + C 2) at the LHC. We study the shapes of several kinematic variables, including the relative pseudorapidity, relative azimuthal angle and the energies of the two leptons, as well as several mass variables M ℓℓ , M eff, \( \sqrt {{{{s}_{{\min }}}}} \), M T2, M CT and M CTx . We focus on the two kinematic extremes of \(\sqrt{S}\) — threshold and infinity — and derive analytical expressions for the differential distributions of several variables, most notably the cos \(\theta_{{\ell -\ell +}}^{*}\) variable proposed by Barr in hep-ph/0511115. For all possible spin assignments of particles A, B and C, we derive the cos \(\theta_{{\ell -\ell +}}^{*}\) differential distribution at threshold, including the effects of spin correlations. Our analytical results help identify the problematic cases for spin discrimination.

Keywords

Supersymmetry Phenomenology Hadronic Colliders 

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Copyright information

© SISSA 2012

Authors and Affiliations

  • Lisa Edelhäuser
    • 1
  • Konstantin T. Matchev
    • 2
  • Myeonghun Park
    • 3
  1. 1.Institute for Theoretical Particle Physics and CosmologyRWTH Aachen UniversityAachenGermany
  2. 2.Physics DepartmentUniversity of FloridaGainesvilleU.S.A.
  3. 3.TH Division, CERNGenevaSwitzerland

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