Some issues in soft SUSYbreaking terms from dilaton/moduli sectors
Abstract
We study the structure of the soft SUSYbreaking terms obtained from some classes of 4D strings under the assumption of dilaton/moduli dominance in the process of SUSYbreaking. We generalize previous analysis in several ways and in particular consider the new features appearing when several moduli fields contribute to SUSY breaking (instead of an overall modulus $T$). Some qualitative features indeed change in the multimoduli case.A general discussion for symmetric Abelian orbifolds as well as explicit examples are given. Certain general sumrules involving soft terms of different particles are shown to apply to large classes of models. Unlike in the overall modulus $T$ case, gauginos may be lighter than scalars even at the treelevel. However, if one insists in getting that pattern of soft terms, these sum rules force some of the scalars to get negative mass$^2$. These tachyonic masses could be a problem for standard model 4D strings but an advantage in the case of stringGUTs.We also discuss the possible effects of offdiagonal metrics for the matter fields which may give rise to flavourchanging neutral currents. Different sources for the bilinear $B$ soft term are studied. It is found that the GiudiceMasiero mechanism for generating a ``$\mu $term'', as naturally implemented in orbifolds, leads to the prediction $tg\beta =1$ at the string scale, independently of the Goldstino direction.
 Publication:

arXiv eprints
 Pub Date:
 August 1995
 arXiv:
 arXiv:hepph/9508258
 Bibcode:
 1995hep.ph....8258B
 Keywords:

 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 27 pages, no figures, Latex