2000/05/12 by Stephen P. Martin
Physics and Astronomy · #Axion #Collider #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Electron #Electroweak interaction #Electroweak scale #Fermion #Gauge (firearms) #Higgs boson #Lepton #Lightest Supersymmetric Particle #Minimal Supersymmetric Standard Model #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Physics beyond the Standard Model #Standard Model (mathematical formulation) #Supersymmetry #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevd.62.095008
published as Phys.Rev. D62 (2000) 095008 · 24 pages, LaTeX, 4 figures
arxiv created 2000/05/12 · openalex publication_date 2000/10/06 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The problem of the origin of the \ensuremathμ parameter in the minimal supersymmetric standard model can be solved by introducing singlet supermultiplets with non-renormalizable couplings to the ordinary Higgs supermultiplets. The Peccei-Quinn symmetry is broken at a scale which is the geometric mean between the weak scale and the Planck scale, yielding a \ensuremathμ term of the right order of magnitude and an invisible axion. These models also predict one or more singlet fermions which have electroweak-scale masses and suppressed couplings to MSSM states. I consider the case that such a singlet fermion, containing the axino as an admixture, is the lightest supersymmetric particle. I work out the relevant couplings in several of the simplest models of this type, and compute the partial decay widths of the next-to-lightest supersymmetric particle involving leptons or jets. Although these decays will have an average proper decay length which is most likely much larger than a typical collider detector, they can occasionally occur within the detector, providing a striking signal. With a large sample of supersymmetric events, there will be an opportunity to observe these decays, and so gain direct information about physics at very high energy scales.