2006/05/31 by D. V. Gioutsos, G.K. Leontaris, G. K. Leontaris +1 · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.1103/physrevd.74.075007
published as Phys.Rev. D74 (2006) 075007 · 27 pages, 7 figures. A short paragraph, a footnote and a reference added
arxiv created 2006/09/11 · openalex publication_date 2006/10/19 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study D-brane inspired models with U(3)\ifmmode×\else\texttimes\fiU(2)\ifmmode×\else\texttimes\fiU(1)N gauge symmetry in the context of split supersymmetry. We consider configurations with one, two and three (N=1,2,3) Abelian branes and derive all hypercharge embeddings which imply a realistic particle content. Then, we analyze the implications of split supersymmetry on the magnitude of the string scale, the gauge coupling evolution, the third family fermion mass relations and the gaugino masses. We consider gauge coupling relations which may arise in parallel as well as intersecting brane scenarios and classify the various models according to their predictions for the magnitude of the string scale and the low energy implications. In the parallel brane scenario where the U(1) branes are superposed to U(2) or U(3) brane stacks, varying the split-SUSY scale in a wide range, we find three distinct cases of models predicting a high, intermediate and low string scale, MS\ensuremath∼1016 GeV, MS\ensuremath∼107 GeV and MS\ensuremath∼104 GeV, respectively. We further find that in the intermediate string scale model the low energy ratio mb/m_\ensuremathτ is compatible with b--\ensuremathτ Yukawa unification at the string scale. Furthermore, we perform a similar analysis for arbitrary Abelian gauge coupling relations at MS corresponding to possible intersecting brane models. We find cases which predict a string scale of the order MS\ensuremath≥1014 GeV that accommodate a right-handed neutrino mass of the same order so that a seesaw type, light, left-handed neutrino component is obtained in the sub-eV range as required by experimental and cosmological data. Finally, a short discussion is devoted to the gaugino masses and the lifetime of the gluino.