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arXiv · hep-ph/0512093

Correlated decays of pair-produced scalar taus

K. Hagiwara·K. Mawatari·D. Rainwater·T. Stelzer
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Abstract

We study the quantum mechanical correlation between two identical neutralinos in the decays of minimal supersymmetric standard model (MSSM) scalar tau (stau) pair produced in e+e- annihilation. Generally, the decay products of scalar (spinless) particles are not correlated. We show that a correlation between two neutralinos appears near pair production threshold, due to a finite stau width and mixing of the staus and/or neutralinos, and because the neutralinos are Majorana. Because the correlation is significant only in a specific kinematical configuration, it can be observed only in supersymmetric models where the neutralino momenta can be kinematically reconstructed, such as in models with R-parity violation.

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K. Hagiwara, K. Mawatari, D. Rainwater, T. Stelzer. 2006-04-12. Correlated decays of pair-produced scalar taus. https://doi.org/10.1103/physrevd.73.075010

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