## Large tan beta in gauge-mediated SUSY-breaking models

We explore some topics in the phenomenology of gauge-mediated SUSY-breaking scenarios having a large hierarchy of Higgs VEVs, upsilon(U)/upsilon(D) = tan beta much greater than 1. Some motivation for this scenario is first presented. We then use a systematic, analytic expansion (including some threshold cor- rections) to calculate the mu-parameter needed for proper electroweak breaking and the radiative corrections to the B-parameter, which fortuitously cancel at leading order, If B = 0 at the messenger scale then tan beta is naturally large and calculable; we calculate it, We then confront this prediction with classical and quantum vacuum stability constraints arising from the Higgs-slepton potential, and indicate the preferred values of the top quark mass and messenger scale(s), The possibility of vacuum instability in a different direction yields an upper bound on the messenger mass scale complementary to the familiar bound from gravitino relic abundance. Next, we calculate the rate for b --> s gamma and show the possibility of large deviations (in the direction currently favored by experiment) from standard-model and small tan beta predictions. Finally, we discuss the implications of these findings and their applicability to future, broader and more detailed investigations. (C) 1997 Elsevier Science B.V.

Published in:
Nuclear Physics B, 501, 2, 297-331
Year:
1997
ISSN:
0550-3213
Keywords:
Laboratories: