Exotic Decays of Heavy B quarks

Heavy vector-like quarks of charge $-1/3$, $B$, have been searched for at the LHC through the decays $B\rightarrow bZ,\, bh,\,tW$. In models where the $B$ quark also carries charge under a new gauge group, new decay channels may dominate. We focus on the case where the $B$ is charged under a $U(1)^\prime$ and describe simple models where the dominant decay mode is $B\rightarrow bZ^\prime\rightarrow b (b\bar{b})$. With the inclusion of dark matter such models can explain the excess of gamma rays from the Galactic center. We develop a search strategy for this decay chain and estimate that with integrated luminosity of 300 fb$^{-1}$ the LHC will have the potential to discover both the $B$ and the $Z'$ for $B$ quarks with mass below $\sim 1.6$ TeV, for a broad range of $Z'$ masses. A high-luminosity run can extend this reach to $2$ TeV.Comment: 28 pages, 10 figures, 3 table

An Effective Z'

We describe a method to couple Z' gauge bosons to the standard model (SM), without charging the SM fields under the U(1)', but instead through effective higher dimension operators. This method allows complete control over the tree-level couplings of the Z' and does not require altering the structure of any of the SM couplings, nor does it contain anomalies or require introduction of fields in non-standard SM representations. Moreover, such interactions arise from simple renormalizable extensions of the SM - the addition of vector-like matter that mixes with SM fermions when the U(1)' is broken. We apply effective Z' models as explanations of various recent anomalies: the D0 same-sign dimuon asymmetry, the CDF W+di-jet excess and the CDF top forward-backward asymmetry. In the case of the W+di-jet excess we also discuss several complementary analyses that may shed light on the nature of the discrepancy. We consider the possibility of non-Abelian groups, and discuss implications for the phenomenology of dark matter as well.Comment: 44 pages; 5 figures. References added, discussion of gamma+jj constraints update

The Determinants of Americans\u27 Attitudes of Representation

This dissertation evaluates how citizens approach the representational relationship in a polarized world. How, if at all, do citizens’ perceptions of their legislators change when party identification dominates the political landscape? The answer from this study may be surprising to casual observers of American politics. First, I find that Americans’ views of their legislators are dynamic. Using original, nationally representative panel data, I find that perceptions of legislators move a significant amount on both a non-policy and policy dimension. Second, these levels of affect and congruence are systematically responsive to perceptions of legislators’ public efforts and home styles. Even in a time of clear partisan cleavages, legislators can change their reputations through their home styles. Third, I find that evaluations on both a policy and non-policy dimension have strong, significant effects on the public’s overall approval of the legislator. Although differences on policy at the elite level are quite stark, legislators can still make connections with constituents on a non-policy dimension that will build their support. This phenomenon is not limited to copartisans, but rather extends to independents and members of the opposite party. I extend these findings to examine differences between the public’s views of senators and House members. I find that structural forces lead Americans to view their two sets of federal legislators in different ways

The Rhetoric of Jesus Christ in the Gospel

A thesis presented to the faculty of the College of Humanities at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Arts by Patrick Scott Tucker on November 25, 1996

Applications of flight control system methods to an advanced combat rotorcraft

Advanced flight control system design, analysis, and testing methodologies developed at the Ames Research Center are applied in an analytical and flight test evaluation of the Advanced Digital Optical Control System (ADOCS) demonstrator. The primary objectives are to describe the knowledge gained about the implications of digital flight control system design for rotorcraft, and to illustrate the analysis of the resulting handling-qualities in the context of the proposed new handling-qualities specification for rotorcraft. Topics covered in-depth are digital flight control design and analysis methods, flight testing techniques, ADOCS handling-qualities evaluation results, and correlation of flight test results with analytical models and the proposed handling-qualities specification. The evaluation of the ADOCS demonstrator indicates desirable response characteristics based on equivalent damping and frequency, but undersirably large effective time-delays (exceeding 240 m sec in all axes). Piloted handling-qualities are found to be desirable or adequate for all low, medium, and high pilot gain tasks; but handling-qualities are inadequate for ultra-high gain tasks such as slope and running landings

Student perceptions of the teaching in online learning: and Australian university case study

Universities have been collecting student feedback on their experiences in teaching and learning for decades. Their voice is usually captured in surveys with quantitative and qualitative data used for quality improvement. Quantitative data are often used to monitor the student experience and used as a key performance measure. As online learning is increasingly taken up in universities there is heightened interest about the student experience. In Australia, Open Universities Australia is the largest national provider of online learning. This paper analyses student perceptions of what is helping and hindering their learning, with a focus on teaching, from one large shareholder university. The eVALUate unit survey was used to collect student feedback from 47696enrolling students in 490 units delivered over seven OUA study periods during 2012. The overall response rate for the unit survey was 24.1%. Students overwhelmingly reported very high levels of satisfaction with their experience. In selected units there were lower levels of satisfaction for quality of teaching and feedback on learning. Students commented that the online interactions with the teacher were most important to their learning and where feedback on their learning and assessments was not provided, this hindering their learning. Hence giving students feedback is an important role of the teacher in helping them learn online

Analysis of simulation methodology for calculation of the heat of transport for vacancy thermodiffusion

Computation of the heat of transport Q*(a) in monatomic crystalline solids is investigated using the methodology first developed by Gillan [J. Phys. C: Solid State Phys. 11, 4469 (1978)] and further developed by Grout and coworkers [Philos. Mag. Lett. 74, 217 (1996)], referred to as the Grout-Gillan method. In the case of pair potentials, the hopping of a vacancy results in a heat wave that persists for up to 10 ps, consistent with previous studies. This leads to generally positive values for Q*(a) which can be quite large and are strongly dependent on the specific details of the pair potential. By contrast, when the interactions are described using the embedded atom model, there is no evidence of a heat wave, and Q*(a) is found to be negative. This demonstrates that the dynamics of vacancy hopping depends strongly on the details of the empirical potential. However, the results obtained here are in strong disagreement with experiment. Arguments are presented which demonstrate that there is a fundamental error made in the Grout-Gillan method due to the fact that the ensemble of states only includes successful atom hops and hence does not represent an equilibrium ensemble. This places the interpretation of the quantity computed in the Grout-Gillan method as the heat of transport in doubt. It is demonstrated that trajectories which do not yield hopping events are nevertheless relevant to computation of the heat of transport Q*(a)