Showing papers by "Ian Low published in 2007"
Posted Content•
28 Jan 2007
TL;DR: In this article, the lightest $CP$-even Higgs boson in the minimal supersymmetric standard model was used to probe the stop sector in a large region of the parameter space.
Abstract: We propose using the lightest $CP$-even Higgs boson in the minimal supersymmetric standard model to probe the stop sector. Unlike measuring stop masses in production/decay processes which requires knowledge of masses and mixing angles of other superparticles, our strategy depends little on supersymmetric parameters other than those in the stop sector in a large region of the parameter space. We show that measurements of the Higgs mass and the production rate in the gluon fusion channel, the dominant channel at the CERN LHC, allow for determination of two parameters in the stop mass-squared matrix, including the off-diagonal mixing term. This proposal is very effective when stops are light and their mixing is large, which coincides with the region where the electroweak symmetry breaking is minimally fine-tuned. We also argue that a lightest $CP$-even Higgs mass in the upper range of allowed values and a production rate significantly smaller than the rate predicted in the standard model would be difficult to reconcile within the minimal supersymmetric standard model, except in extreme corners of the parameter space.
34 citations
TL;DR: In this article, the lightest KK particle (LKP) is stable and can play the role of dark matter, and the authors construct models with a Kaluza-Klein parity in a five-dimensional warped geometry, in an attempt to address the little hierarchy problem present in setups with bulk Standard Model fields.
Abstract: We construct models with a Kaluza-Klein (KK) parity in a five- dimensional warped geometry, in an attempt to address the little hierarchy problem present in setups with bulk Standard Model fields. The lightest KK particle (LKP) is stable and can play the role of dark matter. We consider the possibilities of gluing two identical slices of 5D AdS in either the UV (IR-UV-IR model) or the IR region (UV-IR-UV model) and discuss the model-building issues as well as phenomenological properties in both cases. In particular, we find that the UV-IR-UV model is not gravitationally stable and that additional mechanisms might be required in the IR-UV-IR model in order to address flavor issues. Collider signals of the warped KK parity are different from either the conventional warped extra dimension without KK parity, in which the new particles are not necessarily pair-produced, or the KK parity in flat universal extra dimensions, where each KK level is nearly degenerate in mass. Dark matter and collider properties of a TeV mass KK Z gauge boson as the LKP are discussed.
13 citations