Alternative supersymmetric spectra

We describe the features of supersymmetric spectra, alternative to and qual itatively different from that of most versions of the MSSM. The spectra are motivated by extensions of the MSSM with an extra U(1)' gauge symmetry, ex pected in many grand unified and superstring models, which provide a plausi ble solution to the mu problem, both for models with supergravity and for g auge-mediated supersymmetry breaking. Typically, many or all of the squarks are rather heavy (larger than one TeV), especially for the first two famil ies, as are the sleptons in the supergravity models. However, there is a ri cher spectrum of Higgs particles, neutralinos, and (possibly) charginos. Co ncrete examples of such spectra are presented, and the phenomenological imp lications are briefly discussed. (C) 2000 Published by Elsevier Science B.V . All rights reserved.