Impact of Physical Principles at Very High Energy Scales on the Superparticle Mass Spectrum

TL;DR

This work surveys a broad landscape of high-scale physics scenarios that generate non-universal soft SUSY breaking terms in the MSSM, moving beyond the conventional mSUGRA paradigm. It catalogs concrete frameworks (SU(5), SO(10), hypercolor missing partners, effective SUSY, AMSB, MGM) and string/M-theory constructions, detailing how boundary conditions and RG running shape the weak-scale sparticle spectrum. For each scenario, the authors outline the physical mechanisms, parameter spaces, and how to generate collider predictions with ISAJET, illustrating distinctive mass patterns and decay channels that could guide experimental discrimination. The study aims to connect measurements of sparticle properties to the physics of SUSY breaking and mediation at scales far above the weak scale, informing both theory and collider strategies.

Abstract

We survey a variety of proposals for new physics at high scales that serve to relate the multitude of soft supersymmetry breaking parameters of the MSSM. We focus on models where the new physics results in non-universal soft parameters, in sharp contrast with the usually assumed mSUGRA framework. These include {\it i}) SU(5) and SO(10) grand unified (GUT) models, {\it ii}) the MSSM plus a right-handed neutrino, {\it iii}) models with effective supersymmetry, {\it iv}) models with anomaly-mediated SUSY breaking and gaugino mediated SUSY breaking, {\it v}) models with non-universal soft terms due to string dynamics, and {\it vi}) models based on $M$-theory. We outline the physics behind these models, point out some distinctive features of the weak scale sparticle spectrum, and allude to implications for collider experiments. To facilitate future studies, for each of these scenarios, we describe how collider events can be generated using the program ISAJET. Our hope is that detailed studies of a variety of alternatives will help point to the physics underlying SUSY breaking and how this is mediated to the observable sector, once sparticles are discovered and their properties measured.

Figures (10)

• Figure 1: Running of the soft susy breaking masses between the Planck scale and the GUT scale in the minimal $SU(5)$ model for $\tan\beta =35$. At the GUT scale we have taken $\lambda=1$ and $\lambda'=0.1$ for the Higgs couplings, and $\alpha_{GUT}=0.041$ for the unified gauge coupling.
• Figure 2: Running of the soft susy breaking masses between the Planck scale and the GUT scale in the minimal$SO(10)$ model.
• Figure 3: Running of the soft susy breaking masses between the Planck scale and the GUT scale in the general $SO(10)$ model. The GUT scale Yukawa couplings here are the same as in the $SU(5)$ case.
• Figure 4: Non-universal gaugino masses $M_i$, $i=1,2,3$, in a supersymmetric missing partner model with hypercolor, as a function of the common gaugino mass $M_{H1}=M_{H3}\equiv M_H$ in the hypercolor sector. Two values of the hypercolor gauge couplings are used.
• Figure 5: Various sparticle masses in the hypercolor model.