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arXiv · hep-ph/9601292

Single-photon signal from neutralinos at LEP2

S. Ambrosanio·B. Mele·G. Montagna·O. Nicrosini·F. Piccinini
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Abstract

The production of invisible pairs of lightest neutralinos accompanied by a large-angle hard photon in the reaction $e^+ e^- \to χ^0_1 χ^0_1 γ$ is studied at LEP2 energies. The most general gaugino/higgsino composition of the $χ^0_1$ within the Minimal Supersymmetric Standard Model is assumed. The spectrum of the observed photon is derived within the framework of the $p_t$-dependent structure-function approach, whose accuracy is assessed to be within the foreseen experimental accuracy at LEP2. Higher-order QED corrections due to undetected initial-state radiation are also included. A comparison with the Standard Model main background from $e^+ e^- \to ν\bar νγ$ is performed for optimized photon kinematical cuts. Quantitative conclusions on the signal/background ratio are given for a wide range of values of the SUSY parameters.

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S. Ambrosanio, B. Mele, G. Montagna, O. Nicrosini, F. Piccinini. 1996-08-20. Single-photon signal from neutralinos at LEP2. https://doi.org/10.1016/0550-3213(96)00421-x

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