Arjun Menon

Nonminimal universal extra dimensions

In this paper, we investigate the phenomenological implications of boundary localized terms (BLTs) in the model of universal extra dimensions (UED). In particular, we study the electroweak Kaluza-Klein mass spectrum resulting from BLTs and their effect on electroweak symmetry breaking via the five-dimensional Higgs mechanism. We find that the addition of BLTs to massive five-dimensional fields induces a nontrivial extra-dimensional profile for the zero and nonzero Kaluza-Klein (KK) modes. Hence BLTs generically lead to a modification of standard model parameters and are therefore experimentally constrained, even at tree level. We study standard model constraints on three representative nonminimal UED models in detail and find that the constraints on BLTs are weak. On the contrary, nonzero BLTs have a major impact on the spectrum and couplings of nonzero KK modes. For example, there are regions of parameter space where the lightest Kaluza-Klein particle is either the Kaluza-Klein Higgs boson or the first KK mode of the W{sup 3}.

Hunting quasidegenerate Higgsinos

We present a new strategy to uncover light, quasidegenerate Higgsinos, a likely ingredient in a natural supersymmetric model. Our strategy focuses on Higgsinos with interstate splittings of

Hints of R-parity violation in B decays into τν

O(5\ensuremath{-}50)\text{ }\text{ }\mathrm{GeV}

Goldstini as the decaying dark matter

that are produced in association with a hard, initial-state jet and decay via off-shell gauge bosons to two or more leptons and missing energy,

Higgs Boson Signatures of MSSM Electroweak Baryogenesis

pp\ensuremath{\rightarrow}j+{\overline{)E}}_{T}+{2}^{+}\ensuremath{\ell}

Confronting the moduli-induced lightest-superpartner problem

. The additional jet is used for triggering, allowing us to significantly loosen the lepton requirements and gain sensitivity to small inter-Higgsino splittings. Focusing on the two-lepton signal, we find the seemingly large backgrounds from diboson plus jet,

Standard model explanation of a CDF dijet excess in W j j

\overline{t}t

Constraints on universal extra dimensions from W ′ searches

and

Discovering nonstandard Higgs bosons in the H →ZA channel decay to multileptons

Z/{\ensuremath{\gamma}}^{*}+j

Interaction of Dirac and Majorana neutrinos with weak gravitational fields

can be reduced with careful cuts, and that fake backgrounds appear minor. For Higgsino masses