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On the relic abundance of light photinos

Daniel J. H. Chung·Glennys R. Farrar·Edward W. Kolb
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Abstract

We solve the coupled Boltzmann equation for the system of light photinos interacting with pions and $R^0$'s (the gluon-gluino bound state) to determine the relic abundance of light photinos in the light gaugino scenario. Cosmology bounds the ratio r of the R^0 mass to the photino mass to be less than about 1.8. We also use a model Lagrangian embodying crossing symmetry between the $R^0 \leftrightarrow \photino ππ$ and $R^0 π\leftrightarrow \photino π$ reactions to identify cosmologically favored regions of $R^0$ lifetime as a function of $R^0$ and photino masses.

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Daniel J. H. Chung, Glennys R. Farrar, Edward W. Kolb. 1997-03-22. On the relic abundance of light photinos. https://doi.org/10.1103/physrevd.56.6096

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