We study the rho resonance using lattice QCD, employing a variational method. We scan the resonance region by varying the back-to-back momentum of the pions. To vary the pion momentum we use lattice geometries with one elongated spatial direction. For this study we use three different elongations, which allows us to scan finely the resonance region and compute the phase-shifts. The resonance mass and width are extracted from a fit at two different quark masses and the data is extrapolated to the physical point. I discuss the lattice results and compare them with predictions from different effective models.

"Energy Storage for the Electric Grid – MegaWatts from picoWatts"

Sean J. Hearne, Sandia National Laboratories

Abstract: The rapid expansion of renewable generation onto the US electric grid is driving the need for new grid energy storage options. The impetus for this need is largely based on the variable nature of renewable energy, which can cause instabilities in power delivery and directly impact our daily lives (e.g. our ability to watch Netflix). However, the deployment of energy storage technologies is hampered by high initial cost, often inadequate service lifetimes, and the low monetary value of the services provided. In this presentation, we will discuss the current state of drivers for the utilization of grid energy storage and dive into a few specific examples of how nano-science is being used to understand and control degradation in Li-ion batteries.

Bio: Sean Hearne, Ph.D. Is the manager of the CINT Science group at the Center for Integrated Nanotechnologies (CINT) at Sandia National Laboratories, Albuquerque, New Mexico. The CINT user facility is one of five DOE office of Basic Energy Science funded nanoscience research centers whose mission is to advance the frontiers of nanotechnology. Research efforts within the CINT Science group span energy storage, microscopy, nanofabrication, nanoparticle synthesis and the CINT Discovery Platforms^TM. Prior to managing the CINT Science group, he was the program manager of the Office of Electricity Delivery and Energy Reliability’s Energy Storage program at Sandia National Labs. Sean has a long standing interest in energy storage ranging from fundamental material science in both the transportation and grid sectors and has worked extensively with state and federal agencies on deployment of storage technologies.

Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a Lockheed-Martin Company, for the U.S. Department of Energy under Contract No. DE-AC04-94AL85000.

Title of talk: n-semigroups and covering semigroups.

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Ting Wang will be presenting her exit seminar, titled The Role of Gln146 to the Stability and Activity of Manganese Superoxdide Dismutase.  Ting will be defending her dissertation next week.

Faculty Advisor: Dr. Anne-Francis Miller

Title: Nachman's Inverse Conductivity Result

Abstract: In his 1996 paper, Nachman addressed the inverse conductivity problem in two dimensions.  If the electrical conductivity γ ∈ W^{2, p}(ℝ²)​ and is bounded below, then it is uniquely determined by its corresponding Dirichlet-to-Neumann operator Λ_γ​.  The proof of this result is constructive, involving the scattering problem for the Schrodinger equation at zero energy.  In this talk, we will give an overview of Nachman's approach.

Measurement of the free neutron lifetime with a precision on the order of 1 s (0.1%) has been demonstrated to be experimentally feasible, and a robust measurement at that level of sensitivity would serve to remove the neutron lifetime as a significant source of systematic error in understanding implications of Big Bang Nucleosynthesis for new physics. The current uncertainty in our knowledge of the neutron lifetime is, however, significantly poorer, dominated by a nearly 4-sigma discrepancy between two complementary measurement techniques: the "beam" approach, which detects the products from in-flight decays within a beam of low-energy neutrons, and the "bottle" method, which measures the number of surviving ultracold neutrons (UCN) following confinement in a suitable trapping potential. An incomplete assessment of systematic effects is the most likely explanation for this difference, which must be addressed in order to realize the potential of current experimental technology. A number of candidate systematics unique to UCN bottle experiments are known, including, for example, the presence of loss mechanisms associated with UCN-matter interactions, the possibility of untrapped UCN populating quasi-stable orbits inside the trap, and the possibility of detection efficiencies which couple to the phase space evolution of the trapped UCN population. The UCNtau collaboration has constructed a large-volume magneto-gravitational trap that eliminates material interactions inside the storage volume by using a ~1 T magnetic field, created by permanent NdFeB magnets in a bowl-shaped Halbach configuration, to trap UCN from the sides and below, and the earth's gravitational field to trap them from above. Used in conjunction with a set of novel in situ UCN detectors that monitor filling and rapidly count surviving UCN after storage, this configuration is expected to reduce systematic effects associated with previous bottle measurements, which utilized material traps. We have demonstrated that our bottle has a long intrinsic storage time and that, when coupled to the Los Alamos UCN source, is capable of producing repeated measurements with statistical uncertainties at the one second level. I will discuss that work, along with our ongoing efforts to investigate directly the residual systematic effects associated with our experimental configuration. These studies will lead the way towards a next generation of experiments capable of ~0.01% precision, a sensitivity target relevant for direct tests of new physics at the TeV scale.

A Brilliant Madness, a documentary about John Nash. Visit http://www.math.uky.edu/~movies/ for information about the series. 

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Ting Wang will be defending her dissertation: Role of Gln146 to the stability and activity of MnSOD.

Faculty Advisor: Dr. Anne-Frances Miller

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Rawad Hallani will be defending his dissertation: Designing Anthradithiophene Derivatives Suitable For Applications in Organic Electronics and Optoelectronics.

Faculty Advisor: Dr. John Anthony

Dark energy hypothesis aims to explain the accelerated expansion of universe as indicated by evidence from Type Ia supernovae (SN 1a), Cosmic microwave background (CMB) and Baryon acoustic oscillations (BAO) data. Various models have been formulated to explain accelerated
expansion. In this paper, we review the Quintessence and Barotropic fluid models. We will discuss various parameters that can be used to distinguish these models in w-w' plane, where w is dark energy equation of state (EOS) and w' is the derivative of w with respect to the logarithm of scale factor. We will also analyze the behavior of w'', that is the second derivative of w with respect to logarithm of scale fact, for phantom and non-phantom region.