arXiv 0804.11562008-04hep-thhep-ph

Minimal Anomalous U(1)' Extension of the MSSM

Pascal Anastasopoulos, Francesco Fucito, Andrea Lionetto, Gianfranco Pradisi, Antonio Racioppi, Yassen S. Stanev

备注：: 45 pages, 8 eps figures, feynmf. Phenomenological section expanded. 2 plots and references added
发表信息：: Phys.Rev.D78:085014,2008
DOI：: 10.1103/PhysRevD.78.085014

英文摘要：

We study an extension of the MSSM by an anomalous abelian vector multiplet and a Stückelberg multiplet. The anomalies are cancelled by the Green-Schwarz mechanism and the addition of Chern-Simons terms. The advantage of this choice over the standard one is that it allows for arbitrary values of the quantum numbers of the extra U(1). As a first step towards the study of hadron annihilations producing four leptons in the final state (a clean signal which might be studied at LHC) we then compute the decays $Z'\to Z_0 \g$ and $Z'\to Z_0 Z_0$. We find that the largest values of the decay rate is $\sim 10^{-4}$ GeV, while the expected number of events per year at LHC is at most of the order of 10.

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