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arXiv · 0707.1587

Constraints on Neutralino masses and mixings from Cosmology and Collider Physics

Ulrich Langenfeld
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Abstract

Bounds on cross section measurements of chargino pair production at LEP yield a bound on the chargino mass. If the GUT relation is assumed, the lightest neutralino must be heavier than $\approx 45 -50\GeV$. If no GUT relation is assumed, no lower bound on the neutralino mass exists. I derive mass bounds on the lightest neutralino from relic density measurements for relativistic and non-relativistic neutralinos and I derive bounds on the selectron mass from the observed limits on the cross section of the neutralino pair production process $e^+e^-\to \x{1}\x{2}$ at LEP, if the lightest neutralino is massless. I further discuss radiative neutralino production and its background at the future ILC. Finally, I present a method to determine the neutralino couplings to right and left handed selectrons and Z bosons from cross section measurements of radiative neutralino production and neutralino pair production at the ILC.

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Ulrich Langenfeld. 2007-08-09. Constraints on Neutralino masses and mixings from Cosmology and Collider Physics. https://arxiv.org/abs/0707.1587

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