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2004

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Articles 4111 - 4140 of 4447

Full-Text Articles in Physical Sciences and Mathematics

Halitpaşa Transpressive Zone: Implications For An Early Pliocene Compressional Phase In Central Western Anatolia, Turkey, Orhan Kaya, Engi̇n Ünay, Gerçek Saraç, Silke Eichhorn, Sabine Hassenrück, Andrea Knappe, Asaf Pekdeğer, Serdar Mayda Jan 2004

Halitpaşa Transpressive Zone: Implications For An Early Pliocene Compressional Phase In Central Western Anatolia, Turkey, Orhan Kaya, Engi̇n Ünay, Gerçek Saraç, Silke Eichhorn, Sabine Hassenrück, Andrea Knappe, Asaf Pekdeğer, Serdar Mayda

Turkish Journal of Earth Sciences

The Late Cenozoic evolution of the eastern Aegean is dominated by widespread continental extension. The most prominent structures are E-W- and NE-SW-trending grabens and intervening horsts, while NW-SE- and N-S-trending faults form the other less important structures. This paper documents the results of recent geological mapping and structural and stratigraphical analysis from the Halitpaşa half graben, which forms the northwestern continuation of the Gediz Graben. Field evidence for a new NW-SE-trending dextral wrench-dominated fault zone (here named the Halitpaşa transpression zone), which involved the thrusting of pre-Palaeogene basement onto Upper Miocene-Lower Pliocene sediments, is presented. The fault zone is correlated …

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Realizations Of The Osp(2,1) Superalgebra And Related Physical Systems, Hayri̇ye Tütüncüler, Ramazan Koç Jan 2004

Realizations Of The Osp(2,1) Superalgebra And Related Physical Systems, Hayri̇ye Tütüncüler, Ramazan Koç

Turkish Journal of Physics

Eigenvalues and eigenfunction of two-boson 2 \times 2 Hamiltonians in the framework of the superalgebra osp(2,1) are determined by presenting a similarity transformation. The Hamiltonians include two bosons and one fermion have been transformed in the form of the one variable differential equations and the conditions for its solvability have been discussed. It is observed that the Hamiltonians of the various physical systems can be written in terms of the generators of the osp(2,1) superalgebra and under some certain conditions their eigenstates can exactly be obtained. In particular, the procedure given here is useful in determining eigenstates of the Jaynes-Cummings …

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Analysis Of One-Nucleon Transfer Cross-Sections, A. K. A. R. Al-Farra Jan 2004

Analysis Of One-Nucleon Transfer Cross-Sections, A. K. A. R. Al-Farra

Turkish Journal of Physics

The angular distributions of ^{26}Mg(^3H,^2H)^{27}Mg and ^{30}Si(^3H,^2H)^{31}Si reactions have been successfully studied using distorted wave Born approximation (DWBA) calculations. The optical model potentials are taken to have Woods-Saxon, parity and spin-orbit interactions. The present analysis gives a satisfactory fit to the forward angle data but grossly over estimates the cross-sections in the backward regions. The spin-orbit potential provides the best description of the experimental data and is found to be necessary to account for the large-angle cross sections. The obtained values of the extracted spectroscopic factors are reasonable.

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Empirical Correlations Of Global Solar Radiation With Meteorological Data For Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk Jan 2004

Empirical Correlations Of Global Solar Radiation With Meteorological Data For Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk

Turkish Journal of Physics

Multiple linear regression models were developed to estimate the monthly average daily global solar radiation using ten parameters during a period of sixteen years (1984 to 1999) for Onne, Nigeria; the extraterrestrial radiation, average daily temperature, ratio of minimum and maximum daily temperature, relative humidity, ratio of sunshine duration, solar declination, average soil temperature, average pan evaporimeter, average rain fall and average daily dew. Even though up to ten variable correlations has been developed; the results showed that eight variable correlations with the highest value of correlation coefficient R gives the best result when considering the error terms (mean percentage …

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Self Ionization Probabilities Following De-Excitation Decay Of K-Shell Vacancy In Atoms Z = 10--80, Adel M. El-Shemi Jan 2004

Self Ionization Probabilities Following De-Excitation Decay Of K-Shell Vacancy In Atoms Z = 10--80, Adel M. El-Shemi

Turkish Journal of Physics

The average number of ejected electrons and the probability of ion charge state distributions following K-shell ionization in atoms from Z = 10 to Z = 80 were calculated. Monte Carlo simulation technique was used to simulate all possible pathways of radiative and non-radiative transitions to fill the inner-shell ionization in excited atoms. The radiative and non-radiative branching ratios were calculated from Multiconfiguration Dirac-Fock (MCDF) and Dirac-Fock-Slater (DFS) wave functions. The average number of ejected electrons in atoms with Z = 10 is about two, because the non-radiative transitions exceed radiative transitions by 98\%. The mean number of ejected electrons …

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Effect Of Development Time On Polymer Phase Separation In A Pmma Resist, Mohammad Naeem Khalid, Shazia Yasin, Mohammad Riaz Khan Jan 2004

Effect Of Development Time On Polymer Phase Separation In A Pmma Resist, Mohammad Naeem Khalid, Shazia Yasin, Mohammad Riaz Khan

Turkish Journal of Physics

Developer composition type and development technique are known to influence surface and edge roughness in polymethylemethacrylate (PMMA); and it is during development, we believe, that the result is most influenced by the phase separation into polymer-rich and polymer-poor regions. This polymer phase separation is more prominent in a weaker developer and low temperature. In this paper, we investigate the effect of development time on the extent of polymer phase separation in an exposed PMMA developed in a standard developer i.e. 1:3 MIBK:IPA at 20 °C and rinsed in pure IPA for 30 sec. The polymer phase separation is found to …

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Electrical Properties Of Hydrogen Transport Vpe Grown N-Cdte Epilayers On Znte/Gaas, Murat Bayhan Jan 2004

Electrical Properties Of Hydrogen Transport Vpe Grown N-Cdte Epilayers On Znte/Gaas, Murat Bayhan

Turkish Journal of Physics

Electrical characterisation of n-CdTe epilayers grown by hydrogen transport vapour phase epitaxy (H_2T-VPE) on insulating ZnTe/(100)GaAs substrates through the temperature dependent Hall measurements is reported. Double-crystal X-ray diffraction assessments indicate the material high crystalline quality. Samples grown at temperatures, T_G < 650 °C were p-type, but appeared to be n-type for the temperatures above T_G > 650 °C. Hall measurements performed on n-type samples of different thicknesses grown at T_G = 764 °C showed room temperature carrier densities in the range of 10^{11}-10^{14} cm^{-3}. The electron density and Hall mobility characteristics may be in principle well explained with a two-level affective model. The model of scattering by lattice and ionised impurity were found to be limiting …

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On-Road Motor Vehicle Emissions From Around The World, Donald H. Stedman, Gary A. Bishop Jan 2004

On-Road Motor Vehicle Emissions From Around The World, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

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On-Road Emissions In Asia Measured By Remote Sensing, Donald H. Stedman, Gary A. Bishop, Niranjan Vescio, Nitin Manawat, Peter Mcclintock Jan 2004

On-Road Emissions In Asia Measured By Remote Sensing, Donald H. Stedman, Gary A. Bishop, Niranjan Vescio, Nitin Manawat, Peter Mcclintock

Fuel Efficiency Automobile Test Publications

On-road emissions are precisely the emissions which are impacting the air quality and which need to be controlled if air quality improvements are desired. Remote sensing measures mass emissions of CO, HC, NO and smoke per kg (or per L) of fuel burned. On-road emissions are not certification emissions for new vehicles, although new vehicles measured on-road most often provide remote sensing readings well within their certification values. On-road emissions are not the same as readings from scheduled emission tests, although on average the two correlate very well. The major difference between scheduled emission tests and on-road emissions readings is …

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Mae Sae Basin And Wiang Nong Lom: Radiocarbon Dating And Relation To The Active Strike-Slip Mae Chan Fault, Northern Thailand, Spencer H. Wood, Fongsaward S. Singharajwarapan, Tharaporn Bundarnsin, Eric Rothwell Jan 2004

Mae Sae Basin And Wiang Nong Lom: Radiocarbon Dating And Relation To The Active Strike-Slip Mae Chan Fault, Northern Thailand, Spencer H. Wood, Fongsaward S. Singharajwarapan, Tharaporn Bundarnsin, Eric Rothwell

Geosciences Faculty Publications and Presentations

The Mai Sai basin and the Wiang Nong Lom swamp lie north of, and adjacent to, the northeast-trending Mae Chan fault, which is a left -lateral strike-slip fault in northernmost Thailand. The sediment in the Mae Sai basin is about 600 meters thick. The Mae Sai basin has an anticlinal fold below a 390-meter depth. This fold is buried by broadly downwarped sediment. In the Wiang Nong Lom swamp, sediment is about 170 meters thick. Radiocarbon ages from a 2.7-meter auger hole at Ko Mae Mai in the Wiang Nong Lom swamp show that 0.5 meter of sediment accumulated in …

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Survival And Habitat Preferences Of White Marlin (Tetrapturus Albidus) Released From The Western North Atlantic Recreational Fishery, Andrij Z. Horodysky Jan 2004

Survival And Habitat Preferences Of White Marlin (Tetrapturus Albidus) Released From The Western North Atlantic Recreational Fishery, Andrij Z. Horodysky

Dissertations, Theses, and Masters Projects

No abstract provided.

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The Growth Of Valuations On Rational Function Fields In Two Variables, Edward Mosteig, Moss Sweedler Jan 2004

The Growth Of Valuations On Rational Function Fields In Two Variables, Edward Mosteig, Moss Sweedler

Mathematics, Statistics and Data Science Faculty Works

Given a valuation on the function field k( x; y), we examine the set of images of nonzero elements of the underlying polynomial ring k[ x; y] under this valuation. For an arbitrary field k, a Noetherian power series is a map z : Q --> k that has Noetherian (i.e., reverse well-ordered) support. Each Noetherian power series induces a natural valuation on k( x; y). Although the value groups corresponding to such valuations are well-understood, the restrictions of the valuations to underlying polynomial rings have yet to be characterized. Let Lambda(n) denote the images under the valuation v of …

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Bounds On Relic Neutrino Masses In The Z-Burst Model, Gabriele U. Varieschi Jan 2004

Bounds On Relic Neutrino Masses In The Z-Burst Model, Gabriele U. Varieschi

Physics Faculty Works

No abstract provided.

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A New Proof Of A Theorem Of Phan, Curtis Bennett, Sergey Shpectorov Jan 2004

A New Proof Of A Theorem Of Phan, Curtis Bennett, Sergey Shpectorov

Mathematics, Statistics and Data Science Faculty Works

We apply diagram geometry and amalgam techniques to give a new proof of a theorem of K.-W. Phan, characterizing the special unitary group as a group generated by certain systems of subgroups SU(2, q(2)).

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Tree Diagrams For String Links Ii: Determining Chord Diagrams, Blake Mellor Jan 2004

Tree Diagrams For String Links Ii: Determining Chord Diagrams, Blake Mellor

Mathematics, Statistics and Data Science Faculty Works

In previous work, we defined the intersection graph of a chord diagram associated with a string link (as in the theory of finite type invariants). In this paper, we look at the case when this graph is a tree, and we show that in many cases these trees determine the chord diagram (modulo the usual 1-term and 4-term relations).

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Higher Dimensional Algebra Vi: Lie 2-Algebra, John C. Baez, Alissa S. Crans Jan 2004

Higher Dimensional Algebra Vi: Lie 2-Algebra, John C. Baez, Alissa S. Crans

Mathematics, Statistics and Data Science Faculty Works

The theory of Lie algebras can be categorified starting from a new notion of `2-vector space', which we define as an internal category in Vect. There is a 2-category 2Vect having these 2-vector spaces as objects, `linear functors' as morphisms and `linear natural transformations' as 2-morphisms. We define a `semistrict Lie 2-algebra' to be a 2-vector space L equipped with a skew-symmetric bilinear functor [ . , . ] : L x L -> L satisfying the Jacobi identity up to a completely antisymmetric trilinear natural transformation called the `Jacobiator', which in turn must satisfy a certain law of its …

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A Molecular Switch Created By In Vitro Recombination Of Nonhomologous Genes, Sarah F. Mitchell Jan 2004

A Molecular Switch Created By In Vitro Recombination Of Nonhomologous Genes, Sarah F. Mitchell

Chemistry and Biochemistry Faculty Works

We have created a molecular switch by the in vitro recombination of nonhomologous genes and subjecting the recombined genes to evolutionary pressure. The gene encoding TEM1 β-lactamase was circularly permuted in a random fashion and subsequently randomly inserted into the gene encoding Escherichia coli maltose binding protein. From this library, a switch (RG13) was identified in which its β-lactam hydrolysis activity was compromised in the absence of maltose but increased 25-fold in the presence of maltose. Upon removal of maltose, RG13's catalytic activity returned to its premaltose level, illustrating that the switching is reversible. The modularity of RG13 was demonstrated …

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Black Carbon In Estuarine And Coastal Ocean Dissolved Organic Matter, Antonio Mannino, H. Rodger Harvey Jan 2004

Black Carbon In Estuarine And Coastal Ocean Dissolved Organic Matter, Antonio Mannino, H. Rodger Harvey

OES Faculty Publications

We measured black carbon (BC) in ultrafiltered, high-molecular weight dissolved organic matter (UDOM) in surface waters of Delaware Bay, Chesapeake Bay, and the adjacent Atlantic Ocean (U.S.A.) to investigate the importance of riverine and estuarine dissolved organic matter (DOM) as a source of BC to the ocean. BC was 5-72% of UDOM-C (27 ± 17%), which corresponds to 8.9 ± 6.5% of dissolved organic carbon (DOC), with higher values in the heavily urbanized midbay region of the Delaware Estuary and lower yields in the river and coastal ocean. The spatial and seasonal distributions of BC along the salinity gradient of …

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Sources And Cycling Of Carbonyl Sulfide In The Sargasso Sea, Gregory A. Cutter, Lynda S. Cutter, Katherine C. Filippino Jan 2004

Sources And Cycling Of Carbonyl Sulfide In The Sargasso Sea, Gregory A. Cutter, Lynda S. Cutter, Katherine C. Filippino

OES Faculty Publications

The cycling of the radiatively important gas carbonyl sulfide (OCS) was studied in surface waters of the Sargasso Sea. In August 1999, surface OCS concentrations averaged 8.6 pmol L-1, showed minor diel variations, and varied little with depth. An OCS precursor, total dissolved organic sulfur (DOS), was lowest at the surface (40 nmol L-1) and increased with depth. The photoproduction rate of OCS from in situ incubations averaged 9.6 pmol L-1 h-1, whereas dark production was 7.0 pmol L-1 h-1. Apparent quantum yields were 10-5-10-7 from 313-436 …

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Relevant Scales In Zooplankton Ecology: Distribution, Feeding, And Reproduction Of The Copepod Acartia Hudsonica In Response To Thin Layers Of The Diatom Skeletonema Costatum, Alexander B. Bochdansky, Stephen M. Bollens Jan 2004

Relevant Scales In Zooplankton Ecology: Distribution, Feeding, And Reproduction Of The Copepod Acartia Hudsonica In Response To Thin Layers Of The Diatom Skeletonema Costatum, Alexander B. Bochdansky, Stephen M. Bollens

OES Faculty Publications

We investigated the interaction of the copepod Acartia hudsonica in relation to thin layers of the diatom Skeletonema costatum. Thin layers have recently received much attention, since they are common and persistent features in the water column, often overlooked by traditional sampling methods. Their frequent abundance in coastal oceans and the high biomass associated with them has led to the assumption that they are important grazing sites of calanoid copepods. We employed 2-m tall tower tanks that allowed us to simulate thin layers. Three variables representative of three time scales were considered: the distribution of copepods in the tanks …

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Light Dependence Of Selenium Uptake By Phytoplankton And Implications For Predicting Selenium Incorporation Into Food Webs, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter, Lynda S. Cutter, Brian Cole Jan 2004

Light Dependence Of Selenium Uptake By Phytoplankton And Implications For Predicting Selenium Incorporation Into Food Webs, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter, Lynda S. Cutter, Brian Cole

OES Faculty Publications

The potentially toxic element selenium is first concentrated from solution to a large but highly variable degree by algae and bacteria before being passed on to consumers. The large loads of abiotic and detrital suspended particles often present in rivers and estuaries may obscure spatial and temporal patterns in Se concentrations at the base of the food web. We used radiotracers to estimate uptake of both selenite (Se(IV)) and C by intact plankton communities at two sites in the Sacramento/San Joaquin River Delta. Our goals were to determine (1) whether C and Se(IV) uptake were coupled, (2) the role of …

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On The Ecological Status Of The Concept "Boundary Conditions" - A Few Methodological Remarks, Lubomira Burchardt, Krzystof Lastowski, Harold G. Marshall Jan 2004

On The Ecological Status Of The Concept "Boundary Conditions" - A Few Methodological Remarks, Lubomira Burchardt, Krzystof Lastowski, Harold G. Marshall

Biological Sciences Faculty Publications

Plant and animal populations are frequently found in habitats where the environmental conditions are considered extreme or challenging for life form to exist. These conditions may be classified as either: (1) Supreme: a situation characteristic of degradation conditions where only a few species live under stress, and (2) Extra-ordinary: habitats that provide high biodiversity that are under stress conditions. Due to the differences in what we consider extreme conditions, it is necessary to distinguish between these two categories, because they are not comparable. Our presentation will include examples of these two extreme environmental categories.

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Graduate School Of Computer And Information Sciences--Master Of Science Degree Programs 2004-2005, Nova Southeastern University Jan 2004

Graduate School Of Computer And Information Sciences--Master Of Science Degree Programs 2004-2005, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

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2004-2005 Nova Southeastern University Farquhar College Of Arts And Sciences Catalog, Nova Southeastern University Jan 2004

2004-2005 Nova Southeastern University Farquhar College Of Arts And Sciences Catalog, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.

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Advances In Pattern Recognition Algorithms, Architectures, And Devices, Mohammad S. Alam, Mohammad A. Karim Jan 2004

Advances In Pattern Recognition Algorithms, Architectures, And Devices, Mohammad S. Alam, Mohammad A. Karim

Office of Research Faculty & Staff Publications

Over the last decade, tremendous advances have been made in the general area of pattern recognition techniques, devices, and algorithms. We have had the distinct pleasure of witnessing this remarkable growth as evidenced through their dissemination in the previous Optical Engineering special sections we have jointly edited— January 1998, March 1998, May 2000, and January 2002. Twenty-six papers were finally accepted for this latest special section, encompassing the recent trends and advancements made in many different areas of pattern recognition techniques utilizing algorithms, architectures, implementations, and devices. These techniques include matched spatial filter based recognition, hit-miss transforms, invariant pattern recognition, …

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Formation Of The Monolithic Silica Gel Column With Bimodal Pore Structure, Wenhui Gao, Gegliang Yang, Jing Yang, Haiyan Liu Jan 2004

Formation Of The Monolithic Silica Gel Column With Bimodal Pore Structure, Wenhui Gao, Gegliang Yang, Jing Yang, Haiyan Liu

Turkish Journal of Chemistry

A biporous monolithic silica gel column possessing both micrometer sized through-pores and nanometer sized mesopores located in the silica skeletons was prepared and the high concentration porogen (e.g., 2 mol/L ammonium hydroxide solution) was use for increasing mesopore size in this work. The mechanism for the preparation of the monolithic column was investigated in detail. Moreover, the effect of the polyethylene glycol concentration in the starting solution was studied and it was found that a lower concentration range was also suitable for forming the interconnected porous structure for the monolithic silica gel column. At lower concentrations, however, the phase separation …

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Istart: Interactive Strategy Training For Active Reading And Thinking, Danielle S. Mcnamara, Irwin B. Levinstein, Chutima Boonthum Jan 2004

Istart: Interactive Strategy Training For Active Reading And Thinking, Danielle S. Mcnamara, Irwin B. Levinstein, Chutima Boonthum

Computer Science Faculty Publications

Interactive Strategy Training for Active Reading and Thinking (iSTART) is a Web-based application that provides young adolescent to college-age students with high-level reading strategy training to improve comprehension of science texts. iSTART is modeled after an effective, human-delivered intervention called self-explanation reading training (SERT), which trains readers to use active reading strategies to self-explain difficult texts more effectively. To make the training more widely available, the Web-based trainer has been developed. Transforming the training from a human-delivered application to a computer-based one has resulted in a highly interactive trainer that adapts its methods to the performance of the students. The …

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Interactive Dna Sequence And Structure Design For Dna Nanotechnology And Dna Computation, Mingjun Zhang, Chaman Sabharwal, Weimin Tao, Tzyh-Jong Tarn, Ning Xi, Guangyong Li Jan 2004

Interactive Dna Sequence And Structure Design For Dna Nanotechnology And Dna Computation, Mingjun Zhang, Chaman Sabharwal, Weimin Tao, Tzyh-Jong Tarn, Ning Xi, Guangyong Li

Computer Science Faculty Research & Creative Works

DNA sequence and structure design are very important for DNA nanotechnology and DNA computation. A computer aided design tool is needed for exploring DNA sequence and structure of interests before experimental synthesis, which is a very time and labor consuming process. In this paper, an interactive DNA sequence and structure design software tool called DNA shop is proposed and implemented.

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Unique Electron Polarimeter Analyzing Power Comparison And Precision Spin-Based Energy Measurement, J. Grames, C.K. Sinclair, J. Mitchell, E. Chudakov, H. Fenker, A. Freyberger, D.W. Higinbotham, M. Poelker, M. Steigerwald, M. Tiefenback, C. Cavata, S. Escoffier, F. Marie, T. Pussieux, P. Vernin, S. Danagoulian, V. Dharmawardane, R. Fatemi, K. Joo, M. Zeier, V. Gorbenko, R. Nasseripour, Brian Raue, R. Suleiman, B. Zihlmann Jan 2004

Unique Electron Polarimeter Analyzing Power Comparison And Precision Spin-Based Energy Measurement, J. Grames, C.K. Sinclair, J. Mitchell, E. Chudakov, H. Fenker, A. Freyberger, D.W. Higinbotham, M. Poelker, M. Steigerwald, M. Tiefenback, C. Cavata, S. Escoffier, F. Marie, T. Pussieux, P. Vernin, S. Danagoulian, V. Dharmawardane, R. Fatemi, K. Joo, M. Zeier, V. Gorbenko, R. Nasseripour, Brian Raue, R. Suleiman, B. Zihlmann

Department of Physics

Precision measurements of the relative analyzing powers of five electron beam polarimeters, based on Compton, Møller, and Mott scattering, have been performed using the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). A Wien filter in the 100 keV beam line of the injector was used to vary the electron spin orientation exiting the injector. High statistical precision measurements of the scattering asymmetry as a function of the spin orientation were made with each polarimeter. Since each polarimeter receives beam with the same magnitude of polarization, these asymmetry measurements permit a high statistical precision comparison of the …

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Fy2004 Annual Report Of The Water Quality Monitoring Project For The Water Quality Protection Program Of The Florida Keys National Marine Sanctuary, Joseph N. Boyer Jan 2004

Fy2004 Annual Report Of The Water Quality Monitoring Project For The Water Quality Protection Program Of The Florida Keys National Marine Sanctuary, Joseph N. Boyer

SERC Research Reports

No abstract provided.

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