Physics Commons^™

Year-2 Progress Report On Numerical Methods For Bgk-Type Kinetic Equations, Steven M. Wise, Evan Habbershaw

Faculty Publications and Other Works -- Mathematics

In this second progress report we expand upon our previous report and preliminary work. Specifically, we review some work on the numerical solution of single- and multi-species BGK-type kinetic equations of particle transport. Such equations model the motion of fluid particles via a density field when the kinetic theory of rarefied gases must be used in place of the continuum limit Navier-Stokes and Euler equations. The BGK-type equations describe the fluid in terms of phase space variables, and, in three space dimensions, require 6 independent phase-space variables (3 for space and 3 for velocity) for each species for accurate simulation. …

Pressure - Temperature Phase Diagram Of Crsite3, J L. Musfeldt, David Mandrus, Zhenxian Liu

Chemistry Publications and Other Works

van der Waals solids are well known to host remarkable phase diagrams with competing phases, unusual energy transfer processes, and elusive states of matter. Among this class of materials, chalcogenides have emerged as the most flexible and relevant platforms for unraveling charge-structure-function relationships. In order to explore the properties of complex chalcogenides under external stimuli, we measured the far infrared spectroscopic response of CrSiTe3 under extreme pressure-temperature conditions. Analysis of the 368 cm−1 Si-Te stretching mode and the manner in which it is screened by the closure of the indirect gap reveals that the insulator-metal transition takes place immediately after …

A Progress Report On Numerical Methods For Bgk-Type Kinetic Equations, Evan Habbershaw, Steven M. Wise

Faculty Publications and Other Works -- Mathematics

In this report we review some preliminary work on the numerical solution of BGK-type kinetic equations of particle transport. Such equations model the motion of fluid particles via a density field when the kinetic theory of rarefied gases must be used in place of the continuum limit Navier-Stokes and Euler equations. The BGK-type equations describe the fluid in terms of phase space variables, and, in three space dimensions, require 6 independent phase-space variables (3 for space and 3 for velocity) for accurate simulation. This requires sophisticated numerical algorithms and efficient code to realize predictions over desired space and time scales. …

Unconventional Computation Including Quantum Computation, Bruce J. Maclennan

Faculty Publications and Other Works -- EECS

Unconventional computation (or non-standard computation) refers to the use of non-traditional technologies and computing paradigms. As we approach the limits of Moore’s Law, progress in computation will depend on going beyond binary electronics and on exploring new paradigms and technologies for information processing and control. This book surveys some topics relevant to unconventional computation, including the definition of unconventional computations, the physics of computation, quantum computation, DNA and molecular computation, and analog computation. This book is the content of a course taught at UTK.

Design Of An Accelerator-Based Shielding Experiment At The Nasa Space Radiation Laboratory Relevant To Enclosed, Shielded Environments In Space, Lawrence H Heilbronn, Michael Sivertz, Adam Rusek, Charlie Pearson, Martha Clowdsley, Luis Castellanos, Natalie Mcgirl, Ashwin Srikrishna, Cary Zeitlin

Faculty Publications and Other Works -- Nuclear Engineering

Recent calculations indicate that the dose equivalent in an enclosed, shielded environment in a galactic cosmic ray field will increase or remain unchanged when shielding thickness increases beyond 20 to 30 g/cm2. This trend is seen out to 100 g/cm2, beyond which calculations were not run since depths greater than this are not envisioned for human missions in deep space. If these calculations are accurate, then an optimal shielding thickness (or narrow range of thicknesses) exists, with important implications for spacecraft and habitat design. Crucially, the calculation reveals a minimum dose equivalent value that cannot be reduced with added shielding, …

Characterization Of The Non-Uniqueness Of Used Nuclear Fuel Burnup Signatures Through A Mesh-Adaptive Direct Search, Steven Skutnik, David R. Davis

Faculty Publications and Other Works -- Nuclear Engineering

The use of passive gamma and neutron signatures from fission indicators is a common means of estimating used fuel burnup, enrichment, and cooling time. However, while characteristic fission product signatures such as ¹³⁴Cs, ¹³⁷Cs and ¹⁵⁴Eu, and others are generally reliable estimators for used fuel burnup within the context where the assembly initial enrichment and the discharge time are known, in the absence of initial enrichment and/or cooling time information (such as when applying NDA measurements in a safeguards/verification context), these fission product indicators no longer yield a unique solution for assembly enrichment, burnup, and cooling time …

The Role Of Matp, Zapa And Zapb In Chromosomal Organization And Dynamics In Escherichia Coli, Jaana Männik, Daniel E. Castillo, Da Yang, George Siopsis, Jaan Männik

Physics and Astronomy Publications and Other Works

Despite extensive research over several decades, a comprehensive view of how the Escherichia coli chromosome is organized within the nucleoid, and how two daughter chromosomes segregate has yet to emerge. Here we investigate the role of the MatP, ZapA and ZapB proteins in organizing the replication terminus (Ter) region and in the chromosomal segregation process. Quantitative image analysis of the fluorescently labeled Ter region shows that the replication terminus attaches to the divisome in a single segment along the perimeter of the cell in a MatP, ZapA and ZapB-dependent manner. The attachment does not significantly affect the bulk chromosome segregation …

Cross Sections Fall 2014/Winter 2015, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Evidence For Divisome Localization Mechanisms Independent Of The Min System And Slma In Escherichia Coli, Matthew W. Bailey, Paola Bisicchia, Boyd T. Warren, David J. Sherratt, Jaan Mannik

Physics and Astronomy Publications and Other Works

Cell division in Escherichia coli starts with assembly of FtsZ protofilaments into a ring-like structure, the Z-ring. Positioning of the Z-ring at midcell is thought to be coordinated by two regulatory systems, nucleoid occlusion and the Min system. In E. coli, nucleoid occlusion is mediated by the SlmA proteins. Here, we address the question of whether there are additional positioning systems that are capable of localizing the E. coli divisome with respect to the cell center. Using quantitative fluorescence imaging we show that slow growing cells lacking functional Min and SlmA nucleoid occlusion systems continue to divide preferentially at …

Cross Sections Spring/Summer 2014, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Cross Sections Fall 2013/Winter 2014, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Computer Code Verification And Cross Section Calculation For Promethium-147, Rita Inez Zell-Lusk

Nuclear Engineering Reports

The goals of this research are to (1) verify the predictions and accuracy of two computer codes which will be utilized in future research on Pm-147 production with data from a previous experiment and to (2) measure the cross section of Pm-147 for single neutron capture producing Pm-148 ground state and Pm-148 metastable state. The research in goal (1) used previous data obtained by James H. Hinderer in 2010 and a sample of Promethium-147 prepared by Rose Boll in 2006. The main elements of the new research done here included a correction of Mr. Hinderer’s data and the subsequent use …

Cross Sections Fall 2012/Winter 2013, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Cross Sections Spring/Summer 2013, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Characterization Of Heavy Ion Beams At The Heavy Ion Medical Accelerator In Chiba Using A Li-Drifted 5-Mm Silicon Detector, Alexander Lang

Nuclear Engineering Reports

Measurements were taken at the Heavy Ion Medical Accelerator in Chiba, Japan (HIMAC) to characterize accelerator beams to assist in the study of various tissue equivalent proportional counters (TEPCs) designed by Colorado State University (CSU), Oklahoma State University (OSU), and the National Aeronautics and Space Administration (NASA). There were four beams that were part of the HIMAC experiment:

• 290 MeV/nucleon carbon
• 150 MeV/nucleon helium
• 500 MeV/nucleon argon
• 500 MeV/nucleon iron

For the first time ever, a single, 5-mm lithium drifted silicon detector was used to characterize the beam and measure the spectrum of particles striking the TEPCs. If successful, this …

Cross Sections Fall 2011, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Cross Sections Spring 2011, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Diamond Detector Beam Tests, Stefan M Spanier

Physics and Astronomy Publications and Other Works

Photos of Application and Tests of diamond pixel detectors at UTK.

Diamond Particle Detectors, Stefan M Spanier, Matt Hollingsworth

Physics and Astronomy Publications and Other Works

Poster presented at the IEEE Conference 2010 in Knoxville. It shows results for charged particle tracking using single-crystalline diamond pixel detectors.

Note On Scalar Mesons, C. Amsler, T. Gutsche, Stefan M Spanier, N.A. Tornqvist

Physics and Astronomy Publications and Other Works

Review article about the light scalar mesons, experimental and theoretical advances during the previous two years. The nature of several scalar mesons is controversial and they include exotic objects like glue-balls. The note is published in the Review of Particle Properties.

Studies Of Mono-Crystalline Cvd Diamond Pixel Detectors, Stefan M Spanier, Matt Hollingsworth

Physics and Astronomy Publications and Other Works

Proceedings of a presentation at the International Pixel 2010 Conference, Grindelwald, Switzerland.

Cross Sections Fall 2010, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Correlations In Proton-Proton Collisions At The Lhc, The Cms Collaboration

Physics and Astronomy Publications and Other Works

Results on two-particle angular correlations for charged particles emitted in proton proton collisions at center-of-mass energies of 0.9, 2.36, and 7 TeV are presented, using data collected with the CMS detector over a broad range of pseudo-rapidity (h) and azimuthal angle (f). Short-range correlations in Dh, which are studied in minimum bias events, are characterized using a simple “independent cluster” parametrization in order to quantify their strength (cluster size) and their extent in h (cluster decay width). Long-range azimuthal correlations are studied differentially as a function of charged particle multiplicity and particle transverse momentum using a 980 nb^-1 data set …

Cms Tracking Performance Results From Early Lhc Operation, The Cms Collaboration

Physics and Astronomy Publications and Other Works

The first LHC pp collisions at centre-of-mass energies of 0.9 and 2.36 TeV were recorded by the CMS detector in December 2009. The trajectories of charged particles produced in the collisions were reconstructed using the all-silicon Tracker and their momenta were measured in the 3.8 T axial magnetic field. Results from the Tracker commissioning are presented including studies of timing, efficiency, signal-to-noise, resolution, and ionization energy. Reconstructed tracks are used to benchmark the performance in terms of track and vertex resolutions, reconstruction of decays, estimation of ionization energy loss, as well as identification of photon conversions, nuclear interactions, and heavy-flavour …

Observation Of The First Bs--> J/Psi Phi Event In Cms, Stefan M Spanier, Giordano Cerizza

Physics and Astronomy Publications and Other Works

Presentation for the International Conference on High Energy Physics, July 2010, Paris, France. The first reconstructed decay of a Bs particle in CMS that is relevant for finding information to explain the matter anti-matter asymmetry in the Universe.

Cross Sections Spring 2010, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

Commissioning And Performance Of The Cms Pixel Tracker With Cosmic Ray Muons, The Cms Collaboration

Physics and Astronomy Publications and Other Works

The pixel detector of the Compact Muon Solenoid experiment consists of three barrel layers and two disks for each endcap. The detector was installed in summer 2008, commissioned with charge injections, and operated in the 3.8 T magnetic field during cosmic ray data taking. This paper reports on the first running experience and presents results on the pixel tracker performance, which are found to be in line with the design specifications of this detector. The transverse impact parameter resolution measured in a sample of high momentum muons is 18 microns.

Cross Sections Fall 2009, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

High Energy Particle Physics At The University Of Tennessee, Stefan M Spanier

Physics and Astronomy Publications and Other Works

Talk given at the Governor's school in 2009. It is an introduction to particle physics.

Cross Sections Spring 2009, Department Of Physics And Astronomy

Cross Sections

No abstract provided.