Physical Sciences and Mathematics Commons^™

Some Physical Problems For Photon Colliders, Ilya F. Ginzburg

Turkish Journal of Physics

Higgs hunting at different colliders is discussed with new possibilities related to photon colliders are discussed. Brief review of discovery potential for new physics is presented.

Physics At Hera+Lc Based \Gammap Colliders, Z. Z. Aydin

Turkish Journal of Physics

In this proceeding I discuss the proposal of constructing a $\gamma p$ collider at DESY based on a Linac-Ring type $ep$ machine, the HERA+LC. A high energy $\gamma$ beam for this collider is produced by the Compton back-scattering of laser photons off the electron beam from the linear accelerator. Using the parameters of the proton ring of HERA and those of the proposed linear $e^{+}e^{-}$ colliders (LC, specifically TESLA, CLIC or Linac1) we expect a luminosity of $L_{\gamma p} =(1-2)\times 10^{31} cm^{-2} s^{-1}$, due to a reasonable improvement of the proton beam. We examine the physics research program for the …

Analysis Of Atmospheric Concentrations Of Radon And Thoron Using Beta Counting Technique, G. S. Islam, S. M. Basunia

Turkish Journal of Physics

This paper presents a detailed theory and experimental procedure for measurement and analysis of mixed radon and thoron in the environment. The technique has been successfully applied to the study of seasonal variations of radon and thoron in the atmosphere around Rajshahi, Banladesh, during the years 1989-1991. The maximum radon concentration in outdoor air was observed in the winter from December to January while the indoor radon concentration was found to be maximum during the monsoon months of July and August. The implication of the results is briefly discussed in the paper.

Effect Of Deposition Conditions On Composition Of Rf-Sputtered Bi-Sr-Ca-Cu-O Thin Films, Ayhan Güldeste

Turkish Journal of Physics

The effect of rf-magnetron sputtering conditions on as-deposited film composition using a stoichiometric Bi_2Sr_2CaCu_2O_y (Bi-2212) target was investigated in an on-axis configuration, as the stoichiometrical control of the film is the most important parameter for the proper study of film characteristics. It was found that substrate target distance up to 55-60 mm may provide a film composition close to the target composition. The sputtering chamber pressure effecting film composition, especially in respect of Bi, is an important parameter which needs very pracise control. Bi ratio in the deposited films increases with increasing Ar pressure while Sr and Ca are not …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 1, January 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Hadamard Difference Sets In Nonabelian 2-Groups With High Exponent, James A. Davis, Joel E. Iiams

Department of Math & Statistics Faculty Publications

Nontrivial difference sets in groups of order a power of 2 are part of the family of difference sets called Hadamard difference sets. In the abelian case, a group of order 2^{2t + 2} has a difference set if and only if the exponent of the group is less than or equal to 2^{t + 2}. In a previous work (R. A. Liebler and K. W. Smith, in “Coding Theory, Design Theory, Group Theory: Proc. of the Marshall Hall Conf.,” Wiley, New York, 1992), the authors constructed a difference set in a nonabelian group of order …

Measurement Of The He Ground State Lamb Shift Via The Two-Photon 1 1S-2 1S Transition, Scott D. Bergeson, A. Balakrishnan, K. G. H. Baldwin, T. B. Lucatorto, J. P. Marangos, T. J. Mcilrath, T. T. O'Brian, S. L. Rolston, C. J. Sansonetti, Jesse Wen, N. Westbrook, C. H. Cheng, E. E. Eyler

Faculty Publications

We have extended two-photon Doppler-free spectroscopy to the vacuum ultraviolet spectral region, to accurately measure the He 1¹S-2¹S transition at 120 nm. Our result is 4984872315(48) MHz. This yields a ground state Lamb shift of 41104(48) MHz, in fair agreement with theory and other experiments. This approach has the potential for significantly better accuracy once improvements in the laser and the wavelength metrology are implemented.

Geometry,Mechanisms, And Significance Of Extensional Folds From Examples In The Rockymountain Basin And Range Province, Susanne U. Janecke, C. J. Vandenburg, J. J. Blankenau

Susanne U. Janecke

No abstract provided.

Overcoming The Multiplex‐Disadvantage Using Maximum‐Likelihood Inversion, Stephen E. Bialkowski

Stephen E. Bialkowski

A maximum-likelihood estimator, derived under quantum-noiselimited measurement conditions, is used to obtain wavenumber-ordered spectra produced by a model Michelson interferometer. The estimator is tested on a number of synthetic interferograms, and results are compared to similar spectra obtained by using the Fourier (cosine) transform. It is found that the maximum-likelihood inversion method does not result in white noise in the spectrum estimate when the spectrum is sparse. It thus may be used to circumvent the main disadvantage in multiplexed spectrometer measurements using quantum-noise-limited detectors for emissionbased measurements. It is also found that maximum-likelihood inversion methods can be used to obtain …

Games To Teach Mathematical Modelling, James A. Powell, J. Cangelosi, A. M. Harris

James A. Powell

We discuss the use of in-class games to create realistic situations for mathematical modelling. Two games are presented which are appropriate for use in post-calculus settings. The first game reproduces predator{prey oscillations and the second game simulates disease propagation in a mixing population. When used creatively these games encourage students to model realistic data and apply mathematical concepts to understanding the data.

A Lattice Model For Computing The Transmissivity Of The Cornea And Sclera, David B. Ameen, Marilyn F. Bishop, Tom Mcmullen

Physics Publications

Abstract

The method of photonic band structure is used to calculate the frequencies of light that propagate in lattice models of the cornea and sclera of the mammalian eye, providing an explanation for transparency in the cornea that first properly accounts for multiple scattering of light. Each eye tissue is modeled as an ordered array of collagen rods, and photonic band structure methods are used to solve Maxwell's equations exactly for these models, a procedure that automatically effectively includes all orders of multiple scattering. These calculations show that the dispersion relation for the cornea is linear in the visible range, …

Florida Keys National Marine Sanctuary Water Quality Monitoring Project: 1998 Annual Report, Ronald Jones, Joseph N. Boyer

SERC Research Reports

No abstract provided.

Mud Creek Urban Nonpoint Source Demonstration, Paul Vendrell, K. Teague

Technical Reports

Northwest Arkansas is the seventh fastest developing area in the nation. The conversion of rolling pastureland into paved city streets, parking lots, and buildings within this rapidly urbanizing region is reducing infiltration and intensifying stormwater runoff. In the city of Fayetteville alone, the population increased from 42,099 to 58,163 between 1990 and 1999, moving the city across the population threshold which will require the Phase II Stormwater Permit process. Approximately half of Fayetteville is included in the Illinois River Watershed, which has been identified as the third highest priority watershed in need of restoration in the state of Arkansas. Mud …

Generation Of Intense Excimer Radiation From High-Pressure Hollow Cathode Discharges, Ahmed El-Habachi, Karl H. Schoenbach

Bioelectrics Publications

By reducing the diameter of the cathode opening in a hollow cathode discharge geometry to values on the order of 100 μm, we were able to operate these discharges in noble gases in a direct current mode up to atmospheric pressure. High-pressure discharges in xenon were found to be strong sources of excimer radiation. Highest intensities at a wavelength of 172 nm were obtained at a pressure of 400 Torr. At this pressure, the vacuum ultraviolet (VUV) radiant power of a single discharge operating at a forward voltage of 220 V and currents exceeding 2 mA reaches values between 6% …

Iowa Academy Of Science Membership Directory, 1998-99, Iowa Academy Of Science

Iowa Academy of Science Documents

Table of Contents:

Editorial Board, Journal ... 5
Committees ... 6
Sections ... 18
ISTS Regional Directors ... 22
Awards of Merit ... 24
Excellence in Science Teaching Awards ... 25
Past Presidents ... 26
Membership Roster ... 27
Corporate Sponsors ... 35

Iowa Academy Of Science 110th Annual Meeting [1998]: Advance Program, Iowa Academy Of Science

Iowa Academy of Science Documents

Contains information about the schedule and presentations for the 1998 annual meeting of the Iowa Academy of Science.

A Framework For Analysing The Hydrolic Condition Of Watersheds, Bruce Mccammon, John Rector, Karl Gebhardt

United States Bureau of Land Management: Staff Publications

The purpose of this guidance is to provide a national framework for hydrologic analysis and related protocols as components of more comprehensive interdisciplinary watershed analysis. This guidance outlines a process for identifying the essential factors needed to describe hydrologic condition from a vast array of possible factors. The information assembled during the process enables those who conduct hydrologic analyses to participate effectively with other interdisciplinary team members in addressing ecosystem and resource management planning issues. The process helps to organize existing information about a watershed in the form of a watershed case file, which displays and interprets critical hydrologic information …

Searching For Leptoquarks At Gamma-P Colliders, S. Atağ

Turkish Journal of Physics

A study for single and pair production of scalar and vector leptoquarks in the collision of high energy $\gamma $ and proton beams is presented. It is shown that future $\gamma p$ colliders may play a complementary role to investigate unknown leptoquark properties.

The Vertex-Edge Visibility Graph Of A Polygon, Joseph O'Rourke, Ileana Streinu

Computer Science: Faculty Publications

We introduce a new polygon visibility graph, the vertex-edge visibility graph GV E, and demonstrate that it encodes more geometric information about the polygon than does the vertex visibility graph GV. © 1998 Elsevier Science B.V.

Computational Geometry Column 34, Pankaj K. Agarwal, Joseph O'Rourke

Computer Science: Faculty Publications

Problems presented at the open-problem session of the 14th Annual ACM Symposium on Computational Geometry are listed.

Percentile Blobs For Image Similarity, Nicholas Howe

Computer Science: Faculty Publications

We present a new algorithm called PBSIM for computing image similarity, based upon a novel method of extracting bloblike features from images. In tests on a classification task using a data set of over 1000 images, PBSIM shows significantly higher accuracy than algorithms based upon color histograms, as well as previously reported results for another approach based upon bloblike features.

Illumination By Floodlights, William Steiger, Ileana Streinu

Computer Science: Faculty Publications

We consider three problems about the illumination of planar regions with floodlights of prescribed angles. Problem 1 is the decision problem: given a wedge W of angle φ ≤ π, n points p1 . . . . . pn in the plane and n angles α1 . . . . . αn such that ∑ni=1 αi ≤ θ, decide whether W can be illuminated by floodlights of angles α1 , . . . , αn placed in some order at the points p1 , . . . , pn and then rotated appropriately. We show that this problem is the …

A Preliminary Assessment Of Wave, Current, And Sediment Interactions On The Louisiana Shoreface Adjacent To The Isles Dernieres, David A. Pepper, Gregory W. Stone, Ping Wang

Geology Faculty Publications

The Louisiana coast is generally characterized as a low wave-energy environment where sediment transport is dominated by the influence of the Mississippi and the Atchafalaya Rivers. Winter cold fronts, however, generate waves and currents that have a significant impact on a variety of Louisiana’s coastal environments, although field data regarding their influence on the inner shelf are extremely sparse. During a 12-d period that included the passage of two cold fronts, waves and near-bed currents were measured on the Louisiana inner-shelf (depth-8 m) using a sophisticated bottom-mounted instrumentation system. Bottom boundary layer parameters were then calculated using wave-current interaction models, …

Guano Mining In Kenyan Lava Tunnel Caves, Jim W. Simons

International Journal of Speleology

Commercial mining of bat guano for agricultural fertilizer only became possible in Kenya through discovery of major deposits in the lava tunnel caves of Mt. Suswa and the North Chyulu Hills in the early 1960’s. This paper provides historical information leading up to the guano mining, describes the cave deposits, outlines the mining under-takings, and provides information on the guano producing bats and insect faunas. The results of guano analyses, details of the tonnages extracted and sold to recipients between 1966 to 1984, and some benefits which resulted from its use on crops are given. A brief outline of attempts …

The Biogeochemical Cycling Of Dissolved Organic Nitrogen In Estuarine Sediments, David J. Burdige, Shilong Zheng

OES Faculty Publications

Benthic fluxes and pore-water profiles of dissolved organic nitrogen and carbon (DON and DOC, respectively) were determined in seasonal studies at contrasting sites in Chesapeake Bay. Pore-water dissolved organic matter (DOM) concentrations were elevated over bottom-water values, generally increased with depth, and ranged from 15 to similar to 160 μM for DON and ~200-2000 μM for DOC. Pore-water DOM concentrations and the C:N ratio of this material showed spatial (depth) and temporal changes that varied among the sites studied. These trends appeared to be related to differences in the types of sediment organic matter (SOM) undergoing remineralization, as well as …

Grand Staircase-Escalante National Monument, Draft Management Plan, Draft Environmental Impact Statement, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

This Draft Management Plan/Draft Environmental Impact Statement describes and analyzes the impacts of five alternatives for managing the public lands within the Monument. The alternatives provide objectives and recommendations to protect and manage Monument Resources. Alternative B is BLM's preferred alternative.

Post-Stocking Dispersal Habitat Use, And Behavioral Acclimation Of Juvenile Razorback Suckers (Xyrauchen Texanus) In Two Colorado River Reservoirs, United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

Information pertaining to post-stocking dispersal and habitat use of endangered razorback sucker (Xyrauchen Texanus) is primarily limited to the adult life stage. Radio or sonic transmitters are normally surgically implanted in the fish's abdominal cavity.

Flood Insurance Study, City Of St. George, Utah, Washington County, Federal Emergency Management Agency

All U.S. Government Documents (Utah Regional Depository)

This Flood Insurance Study investigates the existence and severity of flood hazards in the City of St. George, Washington County, Utah, and aids in the administration of the National Flood Insurance Act of 1964 and the Flood Disaster Protection Act of 1971. This study has developed flood risk data for various areas of the community that will be used to establish actuarial flood insurance rates and assist the community in its efforts to promote sound flood plain management. Minimum flood plain management requirements for participation in the National Flood Insurance Program (NFIP) are set forth in the Code of Federal …

Ruby Canyon/Black Ridge Integrated Resource Management Plan, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

The purpose of this plan is to maintain ecosystem health, facilitate multiple use management, while meeting human needs in providing a diversity of benefit opportunites. The need for the plan is to promote biodiversity and sustainable ecosystems while meeting human needs for a variety of uses such as high quality recreation activities and grazing.

Selected Hydrologic Data For The Central Virgin River Basin Area, Washington And Iron Counties, Utah 1915-97, United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

Hydrologic data were collected in Washington and Iron Counties, Utah, from 1995 to 1997 to better understand the hydrologic system. Data from earlier years also are presented. Data collected from wells include well-completion data, water-level measurements, and physical properties of the water. Data collected from springs and surface-water sites include discharge and physical properties of the water. Selected water samples collected from ground- and surface-water sites were analyzed for isotopes, chlorofluorocarbons and dissolved gases.