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2003

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Full-Text Articles in Physical Sciences and Mathematics

Quaternary Trialkyl(Polyfluoroalkyl)Ammonium Salts Including Liquid Iodides, Om D. Gupta, Douglas Armstrong, Jean'ne M. Shreeve Dec 2003

Quaternary Trialkyl(Polyfluoroalkyl)Ammonium Salts Including Liquid Iodides, Om D. Gupta, Douglas Armstrong, Jean'ne M. Shreeve

Faculty Scholarship – Chemistry

New quaternary ammonium salts that contain polyfluorinated alkyl substituents were prepared by the polyfluoroalkylation of tertiary amines with polyfluorinated alkyl iodides. Metathesis reactions of the iodide salts with fluorine-containing anions resulted in new low melting salts. The iodide salts of the tri(isooctyl)polyfluoroalkyl amines are also liquids at 25°C.


The Prairie Naturalist Volume 35, No.4 December 2003 Dec 2003

The Prairie Naturalist Volume 35, No.4 December 2003

The Prairie Naturalist

HOME RANGE AND MOVEMENTS OF EASTERN AND RIO GRANDE WILD TURKEY FEMALES IN NORTHEASTERN

SOUTH DAKOTA ▪ C. P. Lehman, L. D. Flake, and A. P. Leif

THE BAT FAUNA OF SOUTHEASTERN SOUTH DAKOTA . J. E. Lane, C. L. Buck, and R. M. Brigham

FIRST REPORT OF THE NORTH DAKOTA RARE BIRD COMMITTEE ▪ D. Svingen and R. E. Martin

BREEDING CHRONOLOGY OF DABBLING DUCKS IN MINNEDOSA, MANITOBA ▪ A. M. Wells and H. H. Prince

A LIVE COLLECTION OF A PISTOLGRIP FROM NEBRASKA ▪ S. C. Schainost

NEW NESTING DATES FOR SOME BREEDING BIRDS IN NORTH DAKOTA ▪ …


Lewis And Clark And The Geology Of The Great Plains, Robert F. Diffendal Jr., Anne P. Diffendal Dec 2003

Lewis And Clark And The Geology Of The Great Plains, Robert F. Diffendal Jr., Anne P. Diffendal

School of Natural Resources: Faculty Publications

Meriwether Lewis and William Clark undertook their journey with the Corps of Discovery in 1804-1806 in order to explore the area that the United States had purchased from France in 1803. Then known as Louisiana, this region included almost everything west of the Mississippi to the continental divide. In order to find the best route across the continent, President Thomas Jefferson charged Lewis with following the Missouri River to its headwaters and then locating rivers flowing down the west side of the Rocky Mountains to the Columbia River and into the Pacific Ocean. Jefferson's written instructions further specified that the …


Charge Transfer In Slow Collisions Of C⁴⁺ With H Below 1 Kev/Amu, Chen-Nan Liu, Anh-Thu Le, C. D. Lin Dec 2003

Charge Transfer In Slow Collisions Of C⁴⁺ With H Below 1 Kev/Amu, Chen-Nan Liu, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

We reexamined charge-transfer cross sections for C⁴⁺ + H collisions for energies from 1 meV/amu to 1 keV/amu using the recently developed hyperspherical close-coupling method. Our results agree with several previous theoretical calculations using molecular-orbital expansion. However, these converged theoretical predictions do not agree with total cross sections from the merged-beam experiments.


Software Development Productivity And Cycle Time Reduction, Victor A. Clincy Dec 2003

Software Development Productivity And Cycle Time Reduction, Victor A. Clincy

Faculty and Research Publications

Increasing software developers' productivity and reducing the software development process' cycle time are key goals for organizations responsible for building software applications. This paper proposes four major areas impacting an organization's ability to increase developer productivity and reduce development cycle time. The four areas are (1) organizational structure and climate, (2) reward system, (3) software development process and (4) the use of software design and testing tools.


Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraft Charging, A. R. Frederickson, John R. Dennison Dec 2003

Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraft Charging, A. R. Frederickson, John R. Dennison

All Physics Faculty Publications

Improved experimental methods are discussed for laboratory measurement of conductivity and electric field in insulating spacecraft material intended for space radiation and plasma environments. These measurement techniques investigate the following features: 1) measurements of conductivity are up to four orders of magnitude smaller than those determined by existing standard methods. 2) Conductivity is altered as radiation accumulates and trapping states fill with electrons. 3) With intense kiloelectronvolt electron irradiation, electrons are continually emitted for hours from the irradiated surface after the irradiation ceases. 4) Charging induced by electron irradiation is strongly modified by the electron-hole pairs that the irradiation generates …


Case 3270: Isometrinae Clark, 1917 (Ecinodermata, Crinoidea): Proposed Emendation Of Spelling To Isometrainae To Remove Homonymy With Isometrinae Kraepelin, 1891 (Arachnida, Scorpiones), Victor Fet, Charles G. Messing Dec 2003

Case 3270: Isometrinae Clark, 1917 (Ecinodermata, Crinoidea): Proposed Emendation Of Spelling To Isometrainae To Remove Homonymy With Isometrinae Kraepelin, 1891 (Arachnida, Scorpiones), Victor Fet, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

The purpose of this application, under Articles 55 and 29 of the Code, is to remove the homonymy between the crinoid subfamily name ISOMETRINAE Clark, 1917 (type genus Isometra Clark, 1908; family ANTEDONIDAE) and the scorpion subfamily name ISOMETRINAE Kraepelin, 1891 (type genus Isometrus Ehrenberg in Hemprich & Ehrenberg, 1828; family BUTHIDAE). It is proposed that the entire generic name of Isometra should be adopted as the stem, so that the correct spelling of the crinoid subfamily will become ISOMETRAINAE Clark, 1917.


Reviewed Work(S): Electronic Tagging And Tracking In Marine Fisheries., David W. Kerstetter Dec 2003

Reviewed Work(S): Electronic Tagging And Tracking In Marine Fisheries., David W. Kerstetter

Marine & Environmental Sciences Faculty Articles

No abstract provided.


Uniform Approximation Of Continuous Functions On A Compact Riemann Surface By Elliptic Modular Forms, Michael Berg Dec 2003

Uniform Approximation Of Continuous Functions On A Compact Riemann Surface By Elliptic Modular Forms, Michael Berg

Mathematics Faculty Works

We show that the graded algebra of elliptic modular forms and their conjugates comprises a uniformly dense subspace of the space of all continuous functions on the compactification of the fundamental domain for the action of SL2(Z) on the complex upper half-plane by fractional linear transformations.


Trust, Collaboration, And Financial Return In Conservation/Development Partnerships, New England Environmental Finance Center Dec 2003

Trust, Collaboration, And Financial Return In Conservation/Development Partnerships, New England Environmental Finance Center

Economics and Finance

In early 2002 the New England Environmental Finance Center hosted a series of roundtable discussions among municipal officials, residential developers, land trust representatives, and others about "Innovative Approaches to Land Conservation and Smart Growth". Among our observations was that for many of the over 20 conservation/development partnerships we discussed in the series, creation and maintenance of trust was central to success or failure of various stages of the partnership. This suggested a link between creation of trust and financial return for traditionally opposed project partners.

To further examine this matter, we interviewed 11 round table participants and asked questions about …


Using Spreadsheets In Geoscience Education: Survey And Annotated Bibliography Of Articles In The Journal Of Geoscience Education Through 2003, Beth Fratesi, H. L. Vacher Dec 2003

Using Spreadsheets In Geoscience Education: Survey And Annotated Bibliography Of Articles In The Journal Of Geoscience Education Through 2003, Beth Fratesi, H. L. Vacher

School of Geosciences Faculty and Staff Publications

Thirty-eight papers published in the Journal of Geoscience Education ( JGE) from 1989 through 2003 explicitly use or recommend the use of spreadsheets as part of classroom or field exercises, projects, or entire courses. Many of the papers include the spreadsheets, and some include the equations. The papers demonstrate how spreadsheets allow students to explore a subject through problem-oriented, interactive, and quantitative exercises. We provide an annotated bibliography and classify the 38 JGE papers by spreadsheet use, mathematics skill area, and geologic subdiscipline. Our discussion of five selected articles — abundance of elements in the Earth’s crust; directional properties of …


Lamb Shift Of Laser-Dressed Atomic States, Ulrich D. Jentschura, Jorg Evers, Martin K. Haas, Christoph H. Keitel Dec 2003

Lamb Shift Of Laser-Dressed Atomic States, Ulrich D. Jentschura, Jorg Evers, Martin K. Haas, Christoph H. Keitel

Physics Faculty Research & Creative Works

We discuss radiative corrections to an atomic two-level system subject to an intense driving laser field. It is shown that the Lamb shift of the laser-dressed states, which are the natural state basis of the combined atom-laser system, cannot be explained in terms of the Lamb shift received by the atomic bare states which is usually observed in spectroscopic experiments. In the final part, we propose an experimental scheme to measure these corrections based on the incoherent resonance fluorescence spectrum of the driven atom.


Xstamps: A Multiversion Timestamps Concurrency Control Protocol For Xml Data, Khin-Myo Win, Wee-Keong Ng, Ee Peng Lim Dec 2003

Xstamps: A Multiversion Timestamps Concurrency Control Protocol For Xml Data, Khin-Myo Win, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the tremendous growth of XML data over the Web, efficient management of such data becomes a new challenge for database community. Several data management solutions, proposed in recent years, extend the capability of traditional database systems to meet the needs of XML data while alternative approaches introduce new generation databases, named as native XML database management systems. Although traditional databases have mature transaction management and concurrency control techniques, there is still a need to tailor techniques for native XML databases in order to deal with distinct characteristics of XML. In this paper, we propose XStamps, a multiversion timestamps concurrency …


Measurement Of High-Q2 Charged Current Cross Sections In E +P Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, D. Krakauer, J. H. Loizides, S. Magill, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan Dec 2003

Measurement Of High-Q2 Charged Current Cross Sections In E +P Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, D. Krakauer, J. H. Loizides, S. Magill, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan

Faculty Publications

Cross sections for e+p charged current deep inelastic scattering at a centre-of-mass energy of 318 GeV have been determined with an integrated luminosity of 60.9 pb-1 collected with the ZEUS detector at HERA. The differential cross sections dσ/dQ2, dσ/dx and dσ/dy for Q2 > 200 GeV2 are presented. In addition, d2σ/dxdQ2 has been measured in the kinematic range 280 GeV2 < Q2 < 17 000 GeV2 and 0.008 < x < 0.42. The predictions of the Standard Model agree well with the measured cross sections. The mass of the W boson propagator is determined to be MW = 78.9 ± 2.0 (stat.) ± 1.8 (syst.) -1.8+2.0 (PDF) GeV from a fit to dσ/dQ2. The chiral structure of the Standard Model is also investigated in terms of the (1-y)2 dependence of the double-differential cross section. The structure-function F2CC has been extracted by combining the measurements presented here with previous ZEUS results from e-p scattering, extending the measurement obtained in a neutrino-nucleus scattering experiment to a significantly higher Q2 region.


Using Dynamic Optimization For Control Of Real Rate Cpu Resource Management Applications, Varin Vahia, Ashvin Goel, David Steere, Jonathan Walpole, Molly H. Shor Dec 2003

Using Dynamic Optimization For Control Of Real Rate Cpu Resource Management Applications, Varin Vahia, Ashvin Goel, David Steere, Jonathan Walpole, Molly H. Shor

Computer Science Faculty Publications and Presentations

In this paper we design a proportional-period optimal controller for allocating CPU to real rate multimedia applications on a general-purpose computer system. We model this computer system problem in to state space form. We design a controller based on dynamic optimization LQR tracking techniques to minimize short term and long term time deviation from the current time stamp and also CPU usage. Preliminary results on an experimental set up are encouraging.


Current Perspectives On Energy And Mass Fluxes In Volcanic Arcs, William Leeman, Jon Davidson, Tobias Fischer, Anita Grunder, Mark Reagan, Martin J. Streck Dec 2003

Current Perspectives On Energy And Mass Fluxes In Volcanic Arcs, William Leeman, Jon Davidson, Tobias Fischer, Anita Grunder, Mark Reagan, Martin J. Streck

Geology Faculty Publications and Presentations

Volcanoes of the Pacific Ring of Fire and other convergent margins worldwide are familiar manifestations of nature's energy, account for about 25% of global volcanic outputs, dominate volcanic gas emissions to the atmosphere, and pose significant physical threats to a large human population. Yet the processes behind this prolific activity remain poorly understood.

An international "State of the Arc" (SOTA) conference was held in August on the slopes of Mt. Hood, Oregon, to address current views on the energy and mass fluxes in volcanic arcs. This meeting brought together some 90 leading experts and students of subduction zones and their …


Groundwater Test Pumping In The Tambellup Townsite, Louise Hopgood Dec 2003

Groundwater Test Pumping In The Tambellup Townsite, Louise Hopgood

Resource management technical reports

Previous studies have concluded that the township of Tambellup is underlain by a perched aquifer. Test pumping and groundwater modelling indicated that groundwater pumping may be an effective way of protecting townsite infrastructure by lowering the water table beneath the town. This report presents results of the test pumping and provides likely bore yields, prediction of pumping influence and likely optimum production bore spacing.


Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics-Task V: Fourth Quarterly Report 09/01/2003-11/30/2003, Samir Moujaes, Yitung Chen Nov 2003

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics-Task V: Fourth Quarterly Report 09/01/2003-11/30/2003, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the TRP proposed application. Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with only very sparse experimental data. Scientists have noticed that the concentration of oxygen dissolved in the liquid alloy could control the corrosion rate of steels exposed to Pb or Pb-Bi. At high …


Ams Radiocarbon Chronology Of Glacier Fluctuations In The South Shetland Islands During The Last Glacial/Interglacial Hemicycle:Implications For Global Climate Change, Brenda L. Hall Nov 2003

Ams Radiocarbon Chronology Of Glacier Fluctuations In The South Shetland Islands During The Last Glacial/Interglacial Hemicycle:Implications For Global Climate Change, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

This award supports a two year program to produce a new reconstruction of ice extent, elevation and thickness at the Last Glacial Maximum (LGM) for the South Shetland Islands in the Antarctic Peninsula. One field season on Livingston Island will involve mapping the areal extent and geomorphology of glacial drift and determining the elevation and distribution of trimlines. In addition, ice flow direction will be determined by mapping and measuring the elevation of erosional features and the position of erratic boulders. One of the main goals of this work will be to demonstrate whether or not organic material suitable for …


Poisonous Snakes And Snakebite In Nebraska, Ron J. Johnson Nov 2003

Poisonous Snakes And Snakebite In Nebraska, Ron J. Johnson

Other Publications in Wildlife Management

Recognizing Poisonous Snakes Prairie rattlesnake Timber rattlesnake Western massasauga Copperhead THE "2-3-4" OF SNAKEBITE Avoiding Poisonous Snakes - The "2" What SHOULD be done in case of Poisonous Snakebite - The "3" What SHOULD NOT Be Done - The "4" Should You Kill Poisonous Snakes on Sight? IN CASE OF POISONOUS SNAKEBITE


Effects Of Deposit-Feeder Gut Passage And Fecal Pellet Encapsulation On Germination Of Dinoflagellate Resting Cysts, David Shull, Anke Kremp, Donald M. (Donald Mark) Anderson Nov 2003

Effects Of Deposit-Feeder Gut Passage And Fecal Pellet Encapsulation On Germination Of Dinoflagellate Resting Cysts, David Shull, Anke Kremp, Donald M. (Donald Mark) Anderson

Environmental Sciences Faculty and Staff Publications

Many species of dinoflagellates spend much of their lives buried in sediments as resting cysts. While on the bottom, cysts may pass through the guts of deposit feeders before conditions become favorable for germination. Little is known, however, about how dinoflagellate cysts are affected by deposit-feeder digestion, fecal pellet formation, and translocation within the sediment column. To answer the question of whether gut passage or pelletization reduces cyst germination, we fed cysts of the dinoflagellate Scrippsiella lachrymosa to 3 polychaete deposit feeders, Capitella sp., Streblospio benedicti, and Polydora cornuta. Fecal pellets of these species have different morphologies …


Laser-Energy Transfer And Enhancement Of Plasma Waves And Electron Beams By Interfering High-Intensity Laser Pulses, P. Zhang, N. Saleh, Shouyuan Chen, Z.M. Sheng, Donald P. Umstadter Nov 2003

Laser-Energy Transfer And Enhancement Of Plasma Waves And Electron Beams By Interfering High-Intensity Laser Pulses, P. Zhang, N. Saleh, Shouyuan Chen, Z.M. Sheng, Donald P. Umstadter

Donald Umstadter Publications

The effects of interference due to crossed laser beams were studied experimentally in the high-intensity regime. Two ultrashort (400 fs), high-intensity (4×1017 and 1.6×1018 W/cm2) and1µm wavelength laser pulses were crossed in a plasma of density 4×1019 cm3. Energy was observed to be transferred from the higher-power to the lower-power pulse, increasing the amplitude of the plasma wave propagating in the direction of the latter. This results in increased electron self-trapping and plasma-wave acceleration gradient, which led to an increased number of hot electrons (by 300%) and hot-electron temperature (by 70%) and a …


Criss-Crossing Laser Beams Zoom Electrons Along, P. Zhang, N. Saleh, Shouyuan Chen, Z.M. Sheng, Donald P. Umstadter Nov 2003

Criss-Crossing Laser Beams Zoom Electrons Along, P. Zhang, N. Saleh, Shouyuan Chen, Z.M. Sheng, Donald P. Umstadter

Donald Umstadter Publications

Crossing two high-intensity laser beams in a plasma (a collection of charged particles) can have some interesting effects. In a recent experiment performed by researchers at the University of Michigan and the Institute of Physics in China, energy from a higher-power laser pulse was transferred to a lower-power laser pulse. The lower-power pulse had been accelerating electrons with its "wakefield" (like a wave accelerating a surfer). The extra energy to this lower-power pulse enhanced the electron acceleration and decreased the divergence of the electron beam. These features are desirable for proposed "laser particle accelerators" that would be powered by relatively …


Unified Cross-Validation Methodology For Selection Among Estimators And A General Cross-Validated Adaptive Epsilon-Net Estimator: Finite Sample Oracle Inequalities And Examples, Mark J. Van Der Laan, Sandrine Dudoit Nov 2003

Unified Cross-Validation Methodology For Selection Among Estimators And A General Cross-Validated Adaptive Epsilon-Net Estimator: Finite Sample Oracle Inequalities And Examples, Mark J. Van Der Laan, Sandrine Dudoit

U.C. Berkeley Division of Biostatistics Working Paper Series

In Part I of this article we propose a general cross-validation criterian for selecting among a collection of estimators of a particular parameter of interest based on n i.i.d. observations. It is assumed that the parameter of interest minimizes the expectation (w.r.t. to the distribution of the observed data structure) of a particular loss function of a candidate parameter value and the observed data structure, possibly indexed by a nuisance parameter. The proposed cross-validation criterian is defined as the empirical mean over the validation sample of the loss function at the parameter estimate based on the training sample, averaged over …


Extension And Partitioning In An Oblique Subduction Zone, New Zealand: Constraints From Three-Dimensional Numerical Modeling, Phaedra Upton, Peter O. Koons, Donna Eberhart-Phillips Nov 2003

Extension And Partitioning In An Oblique Subduction Zone, New Zealand: Constraints From Three-Dimensional Numerical Modeling, Phaedra Upton, Peter O. Koons, Donna Eberhart-Phillips

Earth Science Faculty Scholarship

Contraction, strike slip, and extension displacements along the Hikurangi margin northeast of the North Island of New Zealand coincide with large lateral gradients in material properties. We use a finite- difference code utilizing elastic and elastic-plastic rheologies to build large- scale, three-dimensional numerical models which investigate the influence of material properties on velocity partitioning within oblique subduction zones. Rheological variation in the oblique models is constrained by seismic velocity and attenuation information available for the Hikurangi margin. We compare the effect of weakly versus strongly coupled subduction interfaces on the development of extension and the partitioning of velocity components for …


Giant Metamagnetic Moments In A Granular Fecl2-Fe Heterostructure, Sarbeswar Sahoo, Christian Binek, Wolfgang Kleemann Nov 2003

Giant Metamagnetic Moments In A Granular Fecl2-Fe Heterostructure, Sarbeswar Sahoo, Christian Binek, Wolfgang Kleemann

Christian Binek Publications

Giant moments are observed at low temperatures in a granular FeCl2-Fe heterostructure owing to a local metamagnetic transformation of the antiferromagnetic (AF) FeCl2 matrix due to dipolar interactions. A model of metamagnetically (MM) "dressed" single-domain Fe particles is suggested to explain the observations. These include polydispersive ac susceptibility induced by AF-MM domain configurations and weak exchange bias due to non-spin-flipped AF crystallites.


Hardware-Based Dynamic Storage Management For High-Performance And Real-Time Systems, Victor H. Lai Nov 2003

Hardware-Based Dynamic Storage Management For High-Performance And Real-Time Systems, Victor H. Lai

All Computer Science and Engineering Research

Most modern application programs depend on dynamic storage management to handle allocation and deallocation of memory. Unfortunately conventional software-based storage managers are relatively low performance due to the latency associated with accessing DRAM memory. Consequently, developers of programs with very specialized memory requirements, such a real-time systems, often choose to manage memory manually at the application-code level. This practice can greatly increase performance but it can also significantly complicate the development process. In this thesis we present the design, VHDL implementation and performance evaluation of hardware-based storage manager called the Optimized Hardware Estranged Buddy System (OHEBS). The OHEBS implements four …


Weighting Adjustments For Unit Nonresponse With Multiple Outcome Variables, Sonya L. Vartivarian, Rod Little Nov 2003

Weighting Adjustments For Unit Nonresponse With Multiple Outcome Variables, Sonya L. Vartivarian, Rod Little

The University of Michigan Department of Biostatistics Working Paper Series

Weighting is a common form of unit nonresponse adjustment in sample surveys where entire questionnaires are missing due to noncontact or refusal to participate. Weights are inversely proportional to the probability of selection and response. A common approach computes the response weight adjustment cells based on covariate information. When the number of cells thus created is too large, a coarsening method such as response propensity stratification can be applied to reduce the number of adjustment cells. Simulations in Vartivarian and Little (2002) indicate improved efficiency and robustness of weighting adjustments based on the joint classification of the sample by two …


Search For The Flavor-Changing Neutral Current Decay D0→Μ +Μ - In Pp̅ Collisions At √S =1.96 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Nov 2003

Search For The Flavor-Changing Neutral Current Decay D0→Μ +Μ - In Pp̅ Collisions At √S =1.96 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We report on a search for the flavor-changing neutral current decay D0→µ+µ- in pp̅ collisions at √s =1.96 TeV using 65 pb-1 of data collected by the CDF II experiment at the Fermilab Tevatron Collider. A displaced-track trigger selects long-lived D0 candidates in the D0→µ+µ- search channel, the kinematically similar D0→ π+ π- channel used for normalization, the Cabibbo-favored D0K-π+ channel used to optimize the selection criteria in an unbiased manner, and their charge conjugates. Finding no signal …


Incommensurate Spin Density Waves In Iron Aluminides, D. R. Noakes, A. S. Arrott, M. G. Belk, S. C. Deevi Nov 2003

Incommensurate Spin Density Waves In Iron Aluminides, D. R. Noakes, A. S. Arrott, M. G. Belk, S. C. Deevi

Dartmouth Scholarship

Neutron diffraction in Fe(Al) reveals incommensurate spin density waves (SDWs) in alloys known to be spin glasses. The wave vectors for crystals of Fe(34Al), Fe(40Al), and Fe(43Al) show n varying from 11 to 6 for →q=2π(h±1/n,k±1/n,l±1/n)/a0, where (h,k,l) and a0 characterize the parent bcc lattice of the CsCl structure. The magnetic reflections are present far above the spin-glass freezing temperatures. These SDWs keep the spins on nearest-neighbor Fe atoms close to parallel, in contrast with SDWs in Cr, which keep nearest-neighbor spins close to antiparallel.