Flipped Cryptons and the UHECRs

Cryptons are metastable bound states of fractionally-charged particles that arise generically in the hidden sectors of models derived from heterotic string. We study their properties and decay modes in a specific flipped SU(5) model with long-lived four-particle spin-zero bound states called {\it tetrons}. We show that the neutral tetrons are metastable, and exhibit the tenth-order non-renormalizable superpotential operators responsible for their dominant decays. By analogy with QCD, we expect charged tetrons to be somewhat heavier, and to decay relatively rapidly via lower-order interactions that we also exhibit. The expected masses and lifetimes of the neutral tetrons make them good candidates for cold dark matter (CDM), and a potential source of the ultra-high energy cosmic rays (UHECRs) which have been observed, whereas the charged tetrons would have decayed in the early Universe.Comment: 8 Pages RevTex. New version with expanded introduction to flipped SU(5). Accepted for publication in PR

The Search for a Realistic String Model at LHC

We survey the low-energy supersymmetry phenomenology of a three-family Pati-Salam model constructed from intersecting D6-branes in Type IIA string theory on the T^6/(Z_2 x Z_2) orientifold which possesses many of the phenomenological properties desired in string model-building. In the model, there is no exotic matter in the low-energy spectrum, the correct mass hierarchies for quarks and leptons may be obtained, and the gauge couplings are automatically unified at the string scale. We calculate the supersymmetry breaking soft terms and the corresponding low-energy supersymmetry particle spectra for the model. We find the WMAP constrained dark matter density can be generated in this model in the stau-neutralino and chargino-neutralino coannihilation regions, with expected final states at LHC consisting of low energy leptons and O(GeV) neutrinos. Moreover, we expect final states in the supercritical string cosmology (SSC) scenario to comprise high energy leptons and O(GeV) neutrinos.Comment: 35 pages, 4 figures, accepted for publication in PR

On the politics and conceptualization of gender non-conformity : exploring Thailand’s kathoey population.

The purpose of this thesis is to investigate the politics and conceptualization of gender in Thailand, drawing specifically on the Thai understanding of sex and gender with regard to the kathoey population. This work considers the solidification of a third-gender category and looks to the ways this solidification can inhibit the fluidity of gender and sexuality. It also analyzes the dangers of transnational advocacy and the superimposition of Western queer advocacy and theory on Thai gender identities. I approach this issue from an interdisciplinary framework that seeks to include historical, cultural, and theoretical perspectives. In examining anthropological research, critiques of queer colonialism, and public discourse with regard to the kathoey, I conclude by offering an argument against transnational advocacy and by extrapolating on the dangers of viewing the kathoey from a Western theoretical lens

Enso and Nao Impacts on Plains Winter Seasons in Modern and Historical Periods

Climatological teleconnection patterns, including the phase of the El Niño-Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO), are known predictors for variables such as seasonal temperature and precipitation and tropical cyclone activity. ENSO is known to affect synoptic patterns across the continental United States, particularly by its impact on the upper tropospheric jet stream position. Likewise, NAO is associated with changes in sea level pressure and upper-level jet strengths over the Atlantic Ocean, with upstream impacts affecting North American temperatures and precipitation distribution. While ENSO and NAO are two of many factors that influence global circulations, and by distillation may have a less distinguishable influence on the synoptic pattern, coherent signals can be uncovered in the synoptic environment, based on ENSO phase as well as the NAO, that influence temperatures and precipitation in the central United States