The $\mu$-Parameter of Supersymmetry

TL;DR

This paper reviews the significance of the $$-parameter in supersymmetry, exploring its theoretical origins, phenomenological implications, and proposing new mechanisms within supergravity and gauge-mediation models.

Contribution

It provides a comprehensive review of the $$-parameter's role and introduces novel proposals for its origin in supersymmetric models.

Findings

Correlation between $$ and soft parameters is crucial for phenomenology.

New mechanisms in supergravity and gauge-mediation address the $$-parameter origin.

Theoretical and phenomenological aspects of the $$-parameter are systematically analyzed.

Abstract

The Higgsino mass, or equivalently the $\mu$-parameter, plays an essential role in determining the phenomenology of any supersymmetric model. Particularly, the size of the supersymmetry conserving mu-parameter must be correlated with the size of the soft supersymmetry breaking parameters. The source of this correlation in the underlying ultra-violet theory is one of the mysteries of supersymmetry model building. The puzzle and the various possibilities for its resolution are reviewed, stressing both phenomenological and theoretical aspects. New proposals in the context of supergravity and gauge-mediation frameworks for the soft supersymmetry breaking parameters are examined in some detail.