Affleck-Dine Sneutrino Inflation

Motivated by the coincidence between the Hubble scale during inflation and the typical see-saw neutrino mass scale, we present a supergravity model where the inflaton is identified with a linear combination of right-handed sneutrino fields. The model accommodates an inflaton potential that is flatter than quadratic chaotic inflation, resulting in a measurable but not yet ruled out tensor-to-scalar ratio. Small CP-violation in the neutrino mass matrix and supersymmetry breaking yield an evolution in the complex plane for the sneutrino fields. This induces a net lepton charge that, via the Affleck-Dine mechanism, can be the origin of the observed baryon asymmetry of the universe.Comment: 5 pages, 1 figur

Revisiting Flavor and CP Violation in Supersymmetric SU(5) with Right-Handed Neutrinos

We revisit the minimal supersymmetric SU(5) grand unified theory with three right-handed neutrinos in which universality conditions for soft-supersymmetry breaking parameters are imposed at an input scale above the unification scale. If the Majorana masses for the neutrinos are around $10^{15}$ GeV, large mixing angles and phases in the neutrino sector lead to flavor-violation and CP-violation in the right-handed down squark and left-handed slepton sectors. Since the observed Higgs boson mass and the proton decay constraints indicate sfermions have masses larger than a few TeV, flavor and CP constraints are less restrictive. We explore the constraints on models with a universal soft-supersymmetry breaking input parameters coming from proton stability, electric dipole moments, $\mu\to e\gamma$ decays, and the Higgs mass observed at the LHC. Regions compatible with all constraints can be found if non-zero A-terms are taken.Comment: 28 pages, 4 figures, version accepted PR

A Minimal SU(5) SuperGUT in Pure Gravity Mediation

The lack of evidence for low-scale supersymmetry suggests that the scale of supersymmetry breaking may be higher than originally anticipated. However, there remain many motivations for supersymmetry including gauge coupling unification and a stable dark matter candidate. Models like pure gravity mediation (PGM) evade LHC searches while still providing a good dark matter candidate and gauge coupling unification. Here, we study the effects of PGM if the input boundary conditions for soft supersymmetry breaking masses are pushed beyond the unification scale and higher dimensional operators are included. The added running beyond the unification scale opens up the parameter space by relaxing the constraints on $\tan\beta$. If higher dimensional operators involving the SU(5) adjoint Higgs are included, the mass of the heavy gauge bosons of SU(5) can be suppressed leading to proton decay, $p\to \pi^0 e^+$, that is within reach of future experiments. Higher dimensional operators involving the supersymmetry breaking field can generate additional contributions to the A- and B-terms of order $m_{3/2}$. The threshold effects involving these A- and B-terms significantly impact the masses of the gauginos and can lead to a bino LSP. In some regions of parameter space the bino can be degenerate with the wino or gluino and give an acceptable dark matter relic density.Comment: 37 pages, 27 figure

Low-Scale D-term Inflation and the Relaxion

We present a dynamical cosmological solution that simultaneously accounts for the early inflationary stage of the Universe and solves the supersymmetric little hierarchy problem via the relaxion mechanism. First, we consider an inflationary potential arising from the $D$-term of a new $U(1)$ gauge symmetry with a Fayet--Iliopolous term, that is independent of the relaxion. A technically natural, small $U(1)$ gauge coupling, $g\lesssim 10^{-8}$, allows for a low Hubble scale of inflation, $H_I\lesssim 10^5$ GeV, which is shown to be consistent with Planck data. This feature is then used to realize a supersymmetric two-field relaxion mechanism, where the second field is identified as the inflaton provided that $H_I\lesssim 10$ GeV. The inflaton controls the relaxion barrier height allowing the relaxion to evolve in the early Universe and scan the supersymmetric soft masses. After electroweak symmetry is broken, the relaxion settles at a local supersymmetry-breaking minimum with a range of $F$-term values that can naturally explain supersymmetric soft mass scales up to $10^6$ GeV.Comment: 37 pages, 4 figure

Naturalizing Supersymmetry with a Two-Field Relaxion Mechanism

We present a supersymmetric version of a two-field relaxion model that naturalizes tuned versions of supersymmetry. This arises from a relaxion mechanism that does not depend on QCD dynamics and where the relaxion potential barrier height is controlled by a second axion-like field. During the cosmological evolution, the relaxion rolls with a nonzero value that breaks supersymmetry and scans the soft supersymmetric mass terms. Electroweak symmetry is broken after the soft masses become of order the supersymmetric Higgs mass term and causes the relaxion to stop rolling for superpartner masses up to $\sim 10^9$ GeV. This can explain the tuning in supersymmetric models, including split-SUSY models, while preserving the QCD axion solution to the strong CP problem. Besides predicting two very weakly-coupled axion-like particles, the supersymmetric spectrum may contain an extra Goldstino, which could be a viable dark matter candidate.Comment: 33 pages, 3 figures; v2: bounds and figures correcte

Modelling Climate - Surface Hydrology Interactions in Data Sparse Areas

This thesis develops tools aimed at the study and prediction of climate effects on land-surface hydrology (in particular streamflow), which require a minimum amount of site specific data. This minimum data requirement allows studies to be performed in areas that are data sparse, such as the developing world. ¶ ..

“Inspiring Imps”: programme evaluation of a football intervention targeting mentally ill health services users through a professional football club

The Active People survey (2010) shows that only 6.5% of disabled individuals participate in sport and exercise 3 times per week, compared with 16.5% of able bodied adults in the UK. Individuals with recognised disabilities have long been excluded from mainstream society. Particularly in sport, disability athletes can be afforded minority status and are treated as such (Nixon, 2000: In Handbook of Sports Studies, edited by J. Coakley and E. Dunning. London: Sage). This stigmatisation can be particularly acute among participants with diagnosed mental or psychological disabilities. Previous research concluded that sport can have positive psychological and social benefits, including improved well-being, motivation and social confidence (Crone and Guy, 2008: International Journal of Mental Health Nursing. 17, 197-207.). The aim of the present study was to investigate the feasibility of a 6 week exercise programme targeting mental ill health service users aged 16+. A weekly 2 hour session of football was introduced to promote health and wellbeing in the target group. Partners included county Football Association and a professional football club. The project enhanced local partnerships and partnerships with other professional football clubs. The key remaining aim is to ensure a sustainable “legacy” is achieved to ensure the continuation delivery of the project. The feasibility of the present study will be assessed using programme evaluation. Programme evaluation uses programme theory to produce a structured framework for assessment of the project (Rossi et al 2004; Evaluation: A systematic Approach. London, Sage). This allows a clear and logical progression from planning to implementation. Participant attrition rates and attendance records will be collected. These data will be supplemented with semi-structured interviews with participants and project stakeholders to assess programme development. The expected overall project outcome is to produce shared learning practice on similar interventions nationwide

A test of resource dependency theory using higher education institution behavioral changes after state based merit aid adoption

Field of study: Educational leadership and policy analysis.Dr. Brad Curs, Dissertation Supervisor.Includes vita."May 2018."The purpose of this study was to analyze whether four-year, public institutions altered their behaviors as their revenue streams changed. I utilized state based merit aid adoption to examine whether institutions altered their functional expenditures and faculty employment behaviors as institutions became more resource dependent on students. The dependent variables concerning functional expenditures analyzed were instruction, research, student services, public services, academic support, institutional support, and scholarships. The dependent variables concerning faculty employment analyzed were part-time faculty, full-time non-tenure-track faculty, and fulltime tenure-track faculty. A difference-in-difference estimation strategy estimated institutional responses to a merit aid program being adopted in their state. The findings indicated that after merit aid adoption in their state, institutions altered their behaviors in ways that indicated they became more resource dependent on students. Specifically, the models indicated that, on average, institutions in states that adopted a merit aid program spent more money on instruction, institutional support, and scholarships and employed more part-time faculty than institutions in states that did not adopt any merit aid program. The findings of this study suggest that if states direct funds to students that institutions will respond as though the students provide the funding and not the state.Includes bibliographical references (pages 213-229)