Phenomenology of non-universal gaugino masses in supersymmetric grand unified theories

Grand unified theories can lead to non-universal boundary conditions for the gaugino masses at the unification scale. We consider the implications of such non-universal boundary conditions for the composition of the lightest neutralino as well as for the upper bound on its mass in the simplest supersymmetric grand unified theory based on the SU(5) gauge group. We derive sum rules for neutralino and chargino masses in different representations of SU(5) which lead to different non-universal boundary conditions for the gaugino masses at the unification scale. We also consider the phenomenological implications of the non-universal gaugino masses arising from a grand unified theory in the context of Large Hadron Collider. In particular we investigate the detection of heavy neutral Higgs bosons $H^0, A^0$ from $H^0, A^0 \to \tilde{\chi}_2^0 \tilde{\chi}_2^0 \to 4l$, and study the possibilities of detecting the neutral Higgs bosons in cascade decays, including the decays $\tilde{\chi}_i^0 \to h^0 (H^0, A^0) \tilde{\chi}_1^0 \to b\bar{b} \tilde{\chi}_1^0$.Comment: 24 pages, uses psrfrag. Typo in Eq. (15) corrected. Added more detailed discussion about non-universality in SUSY SU(5). Parameter space and RGE loop level indicated more clearly. Added a few references. Version to be published in Phys. Rev.