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arXiv · hep-ph/0108006

Superlight gravitinos in electron-photon collisions

Shrihari Gopalakrishna·James Wells
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Abstract

Motivated by recent studies of supersymmetry in higher-dimensional spaces, we discuss the experimental signatures of a superlight gravitino, mass < 0.001 eV. We concentrate on the process (e- gamma -> selectronR gravitino) as a probe of supersymmetry, where a single heavy superpartner and a superlight gravitino are produced. The fact that there is only one heavy superpartner in the final state in this process would require a lower center-of-mass energy for on-shell production compared to conventional pair production. For instance, for a 500 GeV machine, we find that a positive signal will be found if the supersymmetry breaking scale is less than about 2 TeV. If no positive signal is found, this process puts a bound on the supersymmetry breaking scale.

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Shrihari Gopalakrishna, James Wells. 2001-08-22. Superlight gravitinos in electron-photon collisions. https://doi.org/10.1016/s0370-2693(01)01038-3

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