Mid-Atlantic Oil Spill Workshop: Are We Ready? A Regional Workshop as Part of the National Academies and Sea Grant Collaborative Workshop Series

(First paragraph) In 2017, the Gulf Research Program (GRP) and the Health and Medical Division of the National Academies of Sciences, Engineering, and Medicine hosted a workshop to prepare for and respond to major marine oil spills. To address gaps identified at the workshop, GRP reached out to the Sea Grant Oil Spill Science Outreach Program to host a series of regional workshops. The Sea Grant Oil Spill team, based in the Gulf, partnered with state Sea Grant programs across the country to plan and deliver regional workshops in 2018-2019. The goals of the workshops were to raise awareness of the topical areas related to spills, listen to those directly affected by spills, identify regional level needs and priorities for improving preparedness, promote networking among groups who may not have previously interacted, and identify resources to address gaps. These regional workshops focused on public health, social disruption, and economic impacts with the aim to identify regional-level needs and priorities for improving preparedness. The following reports on the regional Mid-Atlantic Workshop

Determining Reheating Temperature at Colliders with Axino or Gravitino Dark Matter

After a period of inflationary expansion, the Universe reheated and reached full thermal equilibrium at the reheating temperature T_R. In this work we point out that, in the context of effective low-energy supersymmetric models, LHC measurements may allow one to determine T_R as a function of the mass of the dark matter particle assumed to be either an axino or a gravitino. An upper bound on their mass may also be derived.Comment: 19 pages, some improvements, JHEP versio

Hybrid Inflation from Supersymmetric SU(5)

A scheme of hybrid inflation is considered in the framework of the minimal supersymmetric SU(5) model with an extra singlet. The relevant role of the cubic term in the adjoint representation in the renormalizable superpotential is pointed out in order to have a quite wide region of initial conditions compatible with inflation efficiency, monopole density and perturbations constraint.Comment: Latex file, 12 pages, 2 figures, revised version with discussion of mass spectrum extended and computation of the spectral index adde

Degenerate Neutrinos and Supersymmetric Inflation

A moderate extension of the minimal supersymmetric standard model which includes a U(1)_(B-L) gauge group (B and L being the baryon and lepton number) and a Peccei-Quinn symmetry, U(1)_PQ, is presented. The hybrid inflationary scenario is automatic and `natural' in this model. The mu problem of the minimal supersymmetric standard model is solved by coupling the electroweak higgses to fields which break U(1)_PQ. Baryon number conservation and, thus, proton stability are automatic consequences of a R-symmetry. Neutrinos are assumed to acquire degenerate masses of about 1.5 eV by coupling to SU(2)_L triplet superfields, thereby providing the hot dark matter of the universe. The inflaton decays into these triplets which, via their subsequent decay, produce a primordial lepton asymmetry later converted into the observed baryon asymmetry of the universe. The gravitino and baryogenesis constraints can be satisfied with `natural' values (of order 10^{-3}) of the relevant coupling constants.Comment: 13 pages, Revtex, minor correction

On the Calderón problem for nonlocal Schrödinger equations with homogeneous, directionally antilocal principal symbols

In this article we consider direct and inverse problems for α-stable, elliptic nonlocal operators whose kernels are possibly only supported on cones and which satisfy the structural condition of directional antilocality as introduced by Y. Ishikawa in the 80s. We consider the Dirichlet problem for these operators on the respective “domain of dependence of the operator” and in several, adapted function spaces. This formulation allows one to avoid natural “gauges” which would else have to be considered in the study of the associated inverse problems. Exploiting the directional antilocality of these operators we complement the investigation of the direct problem with infinite data and single measurement uniqueness results for the associated inverse problems. Here, due to the only directional antilocality, new geometric conditions arise on the measurement domains. We discuss both the setting of symmetric and a particular class of non-symmetric nonlocal elliptic operators, and contrast the corresponding results for the direct and inverse problems. In particular for only “one-sided operators” new phenomena emerge both in the direct and inverse problems: For instance, it is possible to study the problem in data spaces involving local and nonlocal data, the unique continuation property may not hold in general and further restrictions on the measurement set for the inverse problem arise

Particle Dark Matter - A Theorist's Perspective

Dark matter is presumably made of some new, exotic particle that appears in extensions of the Standard Model. After giving a brief overview of some popular candidates, I discuss in more detail the most appealing case of the supersymmetric neutralino.Comment: Invited talk at PASCOS--03, Mumbai, Indi

Observational constraints on the spectral index of the cosmological curvature perturbation

We evaluate the observational constraints on the spectral index $n$, in the context of the $\Lambda$CDM hypothesis which represents the simplest viable cosmology. We first take $n$ to be practically scale-independent. Ignoring reionization, we find at a nominal 2-$\sigma$ level $n\simeq 1.0 \pm 0.1$. If we make the more realisitic assumption that reionization occurs when a fraction $f\sim 10^{-5}$ to 1 of the matter has collapsed, the 2-$\sigma$ lower bound is unchanged while the 1-$\sigma$ bound rises slightly. These constraints are compared with the prediction of various inflation models. Then we investigate the two-parameter scale-dependent spectral index, predicted by running-mass inflation models, and find that present data allow significant scale-dependence of $n$, which occurs in a physically reasonable regime of parameter space.Comment: ReVTeX, 15 pages, 5 figures and 3 tables, uses epsf.sty Improved treatment of reionization and small bug fixed in the constant n case; more convenient parameterization and better treatment of the n dependence in the CMB anisotropy for the running mass case; conclusions basically unchanged; references adde

Low-scale supergravity inflation with R-symmetry

We study a supergravity model of inflation with R-symmetry and a single scalar field, the inflaton, slowly rolling away from the origin. The scales of inflation can be as low as the supersymmetry breaking scale of 10^10 GeV or even the electroweak scale of 10^3 GeV which could be relevant in the context of theories with submillimiter dimensions. Exact analytical solutions are presented and a comparison with related models is given.Comment: 11 pages, 3 figures; added discussion and references in section 2; corrected Eqs. 24 and 26; minor corrections in the table and figures; one fig. added in section 1. Accepted for publication in Physics Letters

Axino dark matter in brane world cosmology

We discuss dark matter in the brane world scenario. We work in the Randall-Sundrum type II brane world and assume that the lightest supersymmetric particle is the axino. We find that the axinos can play the role of cold dark matter in the universe, provided that the five-dimensional Planck mass is bounded both from below and from above. This is possible for higher reheating temperatures compared to the conventional four-dimensional cosmology due to a novel expansion law for the universe.Comment: 1+11 pages, version submitted to JCA