Physical Sciences and Mathematics Commons^™

Λλ Correlation Function In Au+Au Collisions At √SNn=200  Gev, J. Kevin Adkins, Renee Fatemi, Suvarna Ramachandran, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, D. Arkhipkin, E. C. Aschenauer

Physics and Astronomy Faculty Publications

We present ΛΛ correlation measurements in heavy-ion collisions for Au+Au collisions at √^S_NN=200  GeV using the STAR experiment at the Relativistic Heavy-Ion Collider. The Lednický-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for dihyperon searches are discussed.

An Embedded Active Nucleus In The Oh Megamaser Galaxy Iras16399−0937, Dinalva A. Sales, A. Robinson, D. J. Axon, J. Gallimore, P. Kharb, R. L. Curran, C. O'Dea, S. Baum, Moshe Elitzur, R. Mittal

Physics and Astronomy Faculty Publications

We present a multiwavelength study of the OH megamaser galaxy IRAS16399–0937, based on new Hubble Space Telescope (HST)/Advanced Camera for Surveys F814W and Hα+[N II] images and archive data from HST, Two Micron All Sky Survey, Spitzer, Herschel and the Very Large Array. This system has a double nucleus, whose northern (IRAS16399N) and southern (IRAS16399S) components have a projected separation of ~6'' (3.4 kpc) and have previously been identified based on optical spectra as a low ionization nuclear emission line region (LINER) and starburst nucleus, respectively. The nuclei are embedded in a tidally distorted common envelope, …

Implications Of Coronal Line Emission In Ngc 4696*, Marios Chatzikos, R.J.R. Williams, Gary J. Ferland, R. E. A. Canning, A. C. Fabian, J. S. Sanders, P. A. M. Van Hoof, R. M. Johnstone, Matt L. Lykins, R. L. Porter

Physics and Astronomy Faculty Publications

We announce a new facility in the spectral code cloudy that enables tracking the evolution of a cooling parcel of gas with time. For gas cooling from temperatures relevant to galaxy clusters, earlier calculations estimated the [Fe xiv] λ5303/[Fe x] λ6375 luminosity ratio, a critical diagnostic of a cooling plasma, to slightly less than unity. By contrast, our calculations predict a ratio of ∼3. We revisit recent optical coronal line observations along the X-ray cool arc around NGC 4696 by Canning et al., which detected [Fe x] λ6375, but not [Fe xiv] λ5303. We show that these observations are not …

Design Of Organic Ternary Blends And Small-Molecule Bulk Heterojunctions: Photophysical Considerations, Kallarakkal Ramakrishnan Rajesh, Keshab Paudel, Brian Johnson, Rawad Hallani, John E. Anthony, Oksana Ostroverkhova

Chemistry Faculty Publications

We explored relationships between photophysical processes and solar cell characteristics in solution-processable bulk heterojunctions (BHJs), in particular: (1) polymer donor:fullerene acceptor:small-molecule (SM) nonfullerene acceptor, (2) polymer donor:SM donor:SM nonfullerene acceptor, and (3) SM donor:SM nonfullerene or fullerene acceptor. Addition of a nonfullerene SM acceptor to “efficient” polymer:fullerene BHJs led to a reduction in power conversion efficiency (PCE), mostly due to decreased charge photogeneration efficiency and increased disorder. By contrast, addition of an SM donor to “inefficient” polymer:SM nonfullerene acceptor BHJs led to a factor of two to three improvement in the PCE, due to improved charge photogeneration efficiency and transport. …

Confinement-Deconfinement Transition As An Indication Of Spin-Liquid-Type Behavior In Na2Iro3, Zhanybek Alpichshev, Fahad Mahmood, Gang Cao, Nuh Gedik

Physics and Astronomy Faculty Publications

We use ultrafast optical spectroscopy to observe binding of charged single-particle excitations (SE) in the magnetically frustrated Mott insulator Na₂IrO₃. Above the antiferromagnetic ordering temperature (T_N) the system response is due to both Hubbard excitons (HE) and their constituent unpaired SE. The SE response becomes strongly suppressed immediately below T_N. We argue that this increase in binding energy is due to a unique interplay between the frustrated Kitaev and the weak Heisenberg-type ordering term in the Hamiltonian, mediating an effective interaction between the spin-singlet SE. This interaction grows with distance causing …

An Experimental And Theoretical Study Of The Electronic Spectrum Of The Hbcl Free Radical, Mohammed A. Gharaibeh, Ramya Nagarajan, Dennis J. Clouthier, Riccardo Tarroni

Chemistry Faculty Publications

Following our previous discovery of the spectra of the HBX (X = F, Cl, and Br) free radicals [S.-G. He, F. X. Sunahori, and D. J. Clouthier, J. Am. Chem. Soc. 127, 10814 (2005)], the òA″Π-X̃²A' band systems of the HBCl and DBCl free radicals have been studied in detail. The radicals have been prepared in a pulsed electric discharge jet using a precursor mixture of BCl₃ and H₂ or D₂ in high pressure argon. Laser-induced fluorescence (LIF) and single vibronic level emission spectra have been recorded to map out the ground …

Semiconducting Compounds And Devices Incorporating Same, Mark D. Watson

Chemistry Faculty Patents

Disclosed are semiconducting compounds having one or more phthalimide units and/or one or more head-to-head (H-H) substituted biheteroaryl units. Such compounds can be monomeric, oligomeric, or polymeric, and can exhibit desirable electronic properties and possess processing advantages including solution−processability and/or good stability at ambient conditions.

Reductions Of Wheat Yield And Yield Components And Nitrogen Loss Following Frozen Soil Nitrogen Applications, Carrie Ann Knott, Edwin L. Ritchey, Lloyd W. Murdock

Plant and Soil Sciences Research Report

Most wheat producers in Kentucky apply nitrogen (N) as a split application. The first N increment is applied when wheat plants begin actively growing (green-up) in late winter, which is typically in mid- February between growth stages Feekes 2 to 3. The second N increment typically occurs in March when wheat is between Feekes 5 to 6. Many producers in Kentucky, especially Western Kentucky, have become accustomed to beginning first N applications in late January when the ground is frozen and the wheat is still dormant. This practice allows them to apply N to large acreages of wheat while avoiding …

Quality Of Water From Tile Drains In Fields Treated With Poultry Litter In Mclean County, Kentucky, E. Glynn Beck, Lisa Y. Blue, David A. Atwood

Information Circular--KGS

Poultry litter (a mixture of feed, manure, and bedding material) is commonly used as a soil amendment to row-crop fields in western Kentucky. Because of feed additives, litter typically has elevated concentrations of contaminants, including metals and anions. These metals and anions can accumulate in the soil and therefore could be transported to surface water through drainage tiles. In order to assess water quality in tile drains, a pilot study was conducted in 2008 in McLean County, Kentucky, in which 10 tile drains and six drainage ditches were sampled for total metals and anions. Seven of the tile-drained fields were …

An Optical Sprayer Nozzle Flow Rate Sensor, Joseph S. Dvorak, Luke E. Bryant

Biosystems and Agricultural Engineering Faculty Publications

Ensuring proper flow rates from each nozzle on an agricultural sprayer has become even more important as advances continue to be made in precision application technology. In this article, we describe the structure and testing of a sensor technology based on optical cross-correlation to determine the flow rate of individual sprayer nozzles. An advantage of this technology is that it does not require that impellers or other components be placed in the flow, which could cause plugging. The only moving part in the entire system is a solenoid used to inject a tracer dye. The objective of this study was …

The Geologic Context Of Landslide And Rockfall Maintenance Costs In Kentucky, Bethany L. Overfield, Daniel I. Carey, Gerald A. Weisenfluh, Rebecca Wang, Matthew M. Crawford

Report of Investigations--KGS

Kentucky Transportation Cabinet maintenance cost data for landslides and rockfalls were associated with geology along Kentucky roadways in a three-phase study. Work-order costs collected over 7 yr were divided into 1-mi segments, and the segment midpoints were assigned to geologic formation. Formations that were expensive to maintain were not necessarily those that were the most frequently repaired and vice versa. Costs and frequency of repair were greater in eastern and northern Kentucky, where slope and relief are greater than in other parts of the state and shale-bearing geologic units prevail.

Numerical Investigation On Charring Ablator Geometric Effects: Study Of Stardust Sample Return Capsule Heat Shield, Haoyue Weng, Alexandre Martin

Mechanical Engineering Faculty Publications

Sample geometry is very influential in small charring ablative articles where 1D assumption might not be accurate. In heat shield design, 1D is often assumed since the nose radius is much larger than the thickness of charring. Whether the 1D assumption is valid for the heat shield is unknown. Therefore, the geometric effects of Stardust sample return capsule heat shield are numerically studied using a material response program. The developed computer program models material charring, conductive heat transfer, surface energy balance, pyrolysis gas transport and orthotropic material properties in 3D Cartesian coordinates. Simulation results show that the centerline temperatures predicted …

Homogenization Of Stokes Systems And Uniform Regularity Estimates, Shu Gu, Zhongwei Shen

Mathematics Faculty Publications

This paper is concerned with uniform regularity estimates for a family of Stokes systems with rapidly oscillating periodic coefficients. We establish interior Lipschitz estimates for the velocity and L^∞ estimates for the pressure as well as a Liouville property for solutions in ℝ^d. We also obtain the boundary W^1,p estimates in a bounded C¹ domain for any 1 < p < ∞.

Geologic, Geotechnical, And Geophysical Investigation Of A Shallow Landslide, Eastern Kentucky, Matthew M. Crawford, Junfeng Zhu, Steven E. Webb

Report of Investigations--KGS

In eastern Kentucky, landslides occur in colluvial soils or at the colluvium-bedrock contact, and are commonly triggered by heavy rainfall. These slides occur particularly where steep slopes and weak rocks combine with various methods of slope modification. Landslides can damage roadways, infrastructure, and residences, and mitigation costs can exceed $10 million per year.

The Meadowview landslide in Boyd County was investigated to assess the geologic conditions, extent, and behavior of a rainfall-triggered landslide in eastern Kentucky and evaluate the use of electrical resistivity as a tool to characterize a shallow colluvial landslide. Although this type of landslide is common in …

Summary Of The Kentucky River Watershed Watch 2015 Water Sampling Results, Kentucky Water Resources Research Institute

Kentucky River Watershed Watch

No abstract provided.

Lattice Study Of Quark And Glue Momenta And Angular Momenta In The Nucleon, M. Deka, T. Doi, Y. B. Yang, B. Chakraborty, S. J. Dong, Terrence Draper, M. Glatzmaier, M. Gong, H. W. Lin, Keh-Fei Liu, D. Mankame, N. Mathur, T. Streuer

Physics and Astronomy Faculty Publications

We report a complete calculation of the quark and glue momenta and angular momenta in the proton. These include the quark contributions from both the connected and disconnected insertions. The quark disconnected insertion loops are computed with Z₄ noise, and the signal-to-noise ratio is improved with unbiased subtractions. The glue operator is comprised of gauge-field tensors constructed from the overlap operator. The calculation is carried out on a 16³×24 quenched lattice at β=6.0 for Wilson fermions with κ=0.154, 0.155, and 0.1555, which correspond to pion masses at 650, 538, and 478 MeV, respectively. The chirally …

The Characteristic Imset Polytope Of Bayesian Networks With Ordered Nodes, Jing Xi, Ruriko Yoshida

Statistics Faculty Publications

In 2010, M. Studený, R. Hemmecke, and S. Lindner explored a new algebraic description of graphical models, called characteristic imsets. Compared with standard imsets, characteristic imsets have several advantages: they are still unique vector representatives of conditional independence structures, 0-1 vectors, and more intuitive in terms of graphs than standard imsets. After defining a characteristic imset polytope (cim-polytope) as the convex hull of all characteristic imsets with a given set of nodes, they also showed that a model selection in graphical models, which maximizes a quality criterion, can be converted into a linear programming problem over the cim-polytope. However, in …

Kibble-Zurek Scaling In Holographic Quantum Quench: Backreaction, Sumit R. Das, Takeshi Morita

Physics and Astronomy Faculty Publications

We study gauge and gravity backreaction in a holographic model of quantum quench across a superfluid critical transition. The model involves a complex scalar field coupled to a gauge and gravity field in the bulk. In earlier work (arXiv:1211.7076) the scalar field had a strong self-coupling, in which case the backreaction on both the metric and the gauge field can be ignored. In this approximation, it was shown that when a time dependent source for the order parameter drives the system across the critical point at a rate slow compared to the initial gap, the dynamics in the critical region …

Comparison Of The Ground-Motion Attenuation Relationship Between The Wenchuan, China, Area And The Central And Eastern United States, Jiwei Feng, Zhenming Wang, Edward W. Woolery, Shanyou Li

Report of Investigations--KGS

An M_w-7.9 earthquake occurred in Wenchuan, China, in 2008, along the Longmenshan Fault, which is located on the western border of the South China stable continental region. A detailed comparison of the Wenchuan ground-motion attenuation relationships with the relationships for the central and eastern United States (also a stable continental region) showed that the ground-motion prediction equation for the Wenchuan area is similar to those for the central and eastern United States. Thus, the strong-motion records from the Wenchuan earthquake can be used for constraining the ground-motion prediction equation and engineering analysis for the central and eastern United …

Schoenophyllum Aggregatum Zone: Stratigraphic Marker For Investigations Of Mississippian Limestones In Western Kentucky, Garland R. Dever Jr., Preston Mcgrain

Report of Investigations--KGS

Schoenophyllum aggregatum, a Mississippian colonial rugose coral, has a widespread geographic distribution and narrow stratigraphic range in the upper Ste. Genevieve Limestone of western Kentucky. This coral zone serves as a useful stratigraphic marker for commercial and geologic investigations of the extensive limestone deposits formed by the Ste. Genevieve and enclosing limestone units in the region. S. aggregatum is also present in rocks correlative with the Ste, Genevieve that occur in the Monteagle Limestone Slade Formation of south-central Kentucky and the Newman Limestone of southeastern Kentucky.

Is There Space Inside Solid Rock?, Stephen F. Greb, David C. Harris, J. Richard Bowersox

Map and Chart--KGS

No abstract provided.

Mapped Karst Groundwater Basins In The Hopkinsville 30 X 60 Minute Quadrangle, James C. Currens, Joseph A. Ray, Phillip W. O'Dell, Robert J. Blair

Map and Chart--KGS

No abstract provided.

Reassessment Of Risk Genotypes (Grn, Tmem106b, And Abcc9 Variants) Associated With Hippocampal Sclerosis Of Aging Pathology, Peter T. Nelson, Wang-Xia Wang, Amanda B. Partch, Sarah E. Monsell, Otto Valladares, Sally R. Ellingson, Bernard R. Wilfred, Adam C. Naj, Li-San Wang, Walter A. Kukull, David W. Fardo

Pathology and Laboratory Medicine Faculty Publications

Hippocampal sclerosis of aging (HS-Aging) is a common high-morbidity neurodegenerative condition in elderly persons. To understand the risk factors for HS-Aging, we analyzed data from the Alzheimer’s Disease Genetics Consortium and correlated the data with clinical and pathologic information from the National Alzheimer’s Coordinating Center database. Overall, 268 research volunteers with HS-Aging and 2,957 controls were included; detailed neuropathologic data were available for all. The study focused on single-nucleotide polymorphisms previously associated with HS-Aging risk: rs5848 ( GRN ), rs1990622 ( TMEM106B ), and rs704180 ( ABCC9 ). Analyses of a subsample that was not previously evaluated (51 HS-Aging cases …

The Host Galaxies Of X-Ray Selected Active Galactic Nuclei To Z = 2.5: Structure, Star Formation, And Their Relationships From Candels And Herschel/Pacs, Dale D. Kocevski, D. J. Rosario, D. H. Mcintosh, A. Van Der Wel, J. Kartaltepe, P. Lang, P. Santini, S. Wuyts, D. Lutz, M. Rafelski, C. Villforth

Physics and Astronomy Faculty Publications

We study the relationship between the structure and star formation rate (SFR) of X-ray selected low and moderate luminosity active galactic nuclei (AGNs) in the two Chandra Deep Fields, using Hubble Space Telescope imaging from the Cosmic Assembly Near Infrared Extragalactic Legacy Survey (CANDELS) and deep far-infrared maps from the PEP+GOODS-Herschel survey. We derive detailed distributions of structural parameters and FIR luminosities from carefully constructed control samples of galaxies, which we then compare to those of the AGNs. At z ~ 1, AGNs show slightly diskier light profiles than massive inactive (non-AGN) galaxies, as well as modestly higher levels …

Kentucky Water Resources Research Institute Annual Technical Report Fy 2014, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2014 Annual Technical Report for Kentucky consolidates reporting requirements for the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each research project that was conducted during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary a student support during the reporting period, and 5) notable awards and achievements during the year.