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Missouri University of Science and Technology

2005

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Method And System For Electronically Generating Random Answers, Stephen O. Bozzone, Bonnie Bachman Dec 2005

Method And System For Electronically Generating Random Answers, Stephen O. Bozzone, Bonnie Bachman

Economics Faculty Research & Creative Works

The invention concerns a method (300) and system (110) for electronically generating random responses in a portable electronic device (110). The method includes the steps of detecting (316) motion of the portable electronic device, in response to the detecting step, generating (318) the random response and outputting (320) the random response to a user of the portable electronic device. The method can further include the steps of prompting (312) the user to ask a question and following a predetermined time period after prompting the user to ask the question, prompting (314) the user to shake the portable electronic device. The …

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Short-Amplitude High-Frequency Wing Strokes Determine The Aerodynamics Of Honeybee Flight, Douglas L. Altshuler, William B. Dickson, Jason T. Vance, Stephen P. Roberts, Michael H. Dickinson Dec 2005

Short-Amplitude High-Frequency Wing Strokes Determine The Aerodynamics Of Honeybee Flight, Douglas L. Altshuler, William B. Dickson, Jason T. Vance, Stephen P. Roberts, Michael H. Dickinson

Biological Sciences Faculty Research & Creative Works

Most Insects Are Thought to Fly by Creating a Leading-Edge Vortex that Remains Attached to the Wing as It Translates through a Stroke. in the Species Examined So Far, Stroke Amplitude is Large, and Most of the Aerodynamic Force is Produced Halfway through a Stroke When Translation Velocities Are Highest. Here We Demonstrate that Honeybees Use an Alternative Strategy, Hovering with Relatively Low Stroke Amplitude (≈90°) and High Wingbeat Frequency (≈230 Hz). When Measured on a Dynamically Scaled Robot, the Kinematics of Honeybee Wings Generate Prominent Force Peaks during the Beginning, Middle, and End of Each Stroke, Indicating the Importance …

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New Graph Model For Channel Assignment In Ad Hoc Wireless Networks, Maggie Xiaoyan Cheng, S. C. Huang, X. Huang, Weili Wu Dec 2005

New Graph Model For Channel Assignment In Ad Hoc Wireless Networks, Maggie Xiaoyan Cheng, S. C. Huang, X. Huang, Weili Wu

Computer Science Faculty Research & Creative Works

The channel assignment problem in ad hoc wireless networks is investigated. The problem is to assign channels to hosts in such a way that interference among hosts is eliminated and the total number of channels is minimised. Interference is caused by direct collisions from hosts that can hear each other or indirect collisions from hosts that cannot hear each other, but simultaneously transmit to the same destination. A new class of disk graphs (FDD: interFerence Double Disk graphs) is proposed that include both kinds of interference edges. Channel assignment in wireless networks is a vertex colouring problem in FDD graphs. …

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Experimental Study Of The Solids Velocity Field In Gas-Solid Risers, Satish Bhusarapu, Muthanna H. Al-Dahhan, Milorad P. Duduković, Steven Trujillo, Timothy J. O'Hern Dec 2005

Experimental Study Of The Solids Velocity Field In Gas-Solid Risers, Satish Bhusarapu, Muthanna H. Al-Dahhan, Milorad P. Duduković, Steven Trujillo, Timothy J. O'Hern

Chemical and Biochemical Engineering Faculty Research & Creative Works

Solids Flow Dynamics in Gas-Solid Risers is Inherently Complex. Model Refinement through Experimental Validation Requires the Acquisition of Detailed Nonintrusive Measurements. in This Study, Noninvasive Computer-Automated Radioactive Particle Tracking (CARPT) is Employed to Visualize and Quantify in a Three-Dimensional Domain the Solids Dynamics and Mixing in Gas-Solid Risers. This Technique Has the Added Advantage that, along with the Derived Eulerian Solids Flow Field (Time-Average Velocity Map and Various Turbulence Parameters Such as the Reynolds Stresses, Turbulent Kinetic Energy), It Also Provides Directly the Lagrangian Description of the Solids Motion. the Solids Velocity Field Data Are Obtained in Two Different Risers …

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Gamma-Ray Induced Photoconductivity In Pyrex, Quartz, And Vycor, Shoaib Usman, Lubna Shoaib, James N. Anno Dec 2005

Gamma-Ray Induced Photoconductivity In Pyrex, Quartz, And Vycor, Shoaib Usman, Lubna Shoaib, James N. Anno

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Results of an experimental investigation are reported on photoconductive response of Pyrex, Quartz and Vycor. This research was conducted as a feasibility study for developing a new gamma dose measurement device based on the principle of photoconductivity. However, data collected in this study are equally valuable for various other applications where these materials are to be used in high radiation field. Our experiments and analyzes indicated that the selected dosimeter materials exhibit photoconductivity and respond to changes in gamma dose rate within a useful range. Pyrex glass suffered radiation damage at a relatively high dose rate of 0.25 Gys/sup -1/. …

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Extreme Sensitivity Of Differential Momentum Transfer Cross Sections To Target Atom Initial Conditions, Ronald E. Olson, J. Fiol Dec 2005

Extreme Sensitivity Of Differential Momentum Transfer Cross Sections To Target Atom Initial Conditions, Ronald E. Olson, J. Fiol

Physics Faculty Research & Creative Works

Heavy-particle cross sections differential in the momentum transferred to the target are investigated using the classical trajectory Monte Carlo method. with the 3.6  MeV/u Au53++He system as a test case, it is shown that these cross sections are extremely sensitive to the initial target temperature. In particular, when thermal motion is varied for one of the target's initial momentum components between 0 and 25 K the absolute cross sections vary by orders of magnitude and, in addition, their relative shapes undergo major changes. We find that by setting one of the target's transverse momenta to a temperature of 16 K, …

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Nonrelativistic Qed Approach To The Lamb Shift, Ulrich D. Jentschura, Andrzej Czarnecki, Krzysztof Pachucki Dec 2005

Nonrelativistic Qed Approach To The Lamb Shift, Ulrich D. Jentschura, Andrzej Czarnecki, Krzysztof Pachucki

Physics Faculty Research & Creative Works

We calculate the one- and two-loop corrections of order α(Zα)6 and α2(Zα)6, respectively, to the Lamb shift in hydrogenlike systems using the formalism of nonrelativistic quantum electrodynamics. We obtain general results valid for all hydrogenic states with nonvanishing orbital angular momentum and for the normalized difference of S states. These results involve the expectation value of local effective operators and relativistic corrections to Bethe logarithms. The one-loop correction is in agreement with previous calculations for the particular cases of S, P, and D states. The two-loop correction in the order α2(Zα)6 includes …

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Mutual Ionization In 200-Kev H⁻+ He Collisions, T. Ferger, Daniel Fischer, Michael Schulz, R. Moshammer, A. B. Voitkiv, B. Najjari, J. Ullrich Dec 2005

Mutual Ionization In 200-Kev H⁻+ He Collisions, T. Ferger, Daniel Fischer, Michael Schulz, R. Moshammer, A. B. Voitkiv, B. Najjari, J. Ullrich

Physics Faculty Research & Creative Works

We studied mutual ionization in 200-keV H-+He collisions in a kinematically complete experiment by measuring the fully momentum-analyzed recoil ions and both active electrons in coincidence. Comparison of the data to our calculations, based on various theoretical models, show that mutual ionization proceeds predominantly through the interaction between both electrons. The post-collision interaction between the outgoing ejected electrons as well as higher order processes involving the interaction between the core of both collision partners are also important.

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Missouri S&T Magazine Winter 2005, Missouri S&T Marketing And Communications Department, Miner Alumni Association Dec 2005

Missouri S&T Magazine Winter 2005, Missouri S&T Marketing And Communications Department, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.

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A Scalable Correlation Aware Aggregation Strategy For Wireless Sensor Networks, Yujie Zhu, Ramanuja Vedantham, Seung Jong Park, Raghupathy Sivakumar Dec 2005

A Scalable Correlation Aware Aggregation Strategy For Wireless Sensor Networks, Yujie Zhu, Ramanuja Vedantham, Seung Jong Park, Raghupathy Sivakumar

Computer Science Faculty Research & Creative Works

Sensors-to-sink data in wireless sensor networks (WSNs) are typically correlated with each other. Exploiting such correlation when performing data aggregation can result in considerable improvements in the bandwidth and energy performance of WSNs. In order to exploit such correlation, we present a scalable and distributed correlation-aware aggregation structure that addresses the practical challenges in the context of aggregation in WSNs. Through simulations and analysis, we evaluate the performance of the proposed approach with centralized and distributed correlation aware and unaware structures.

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Reliability Measurement Of Mass Storage System For Onboard Instrumentation, Minsu Choi, Nohpill Park, Vincenzo Piuri, Fabrizio Lombardi Dec 2005

Reliability Measurement Of Mass Storage System For Onboard Instrumentation, Minsu Choi, Nohpill Park, Vincenzo Piuri, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

Advances in spaceborne vehicular technology have made possible the long-life duration of the mission in harsh cosmic environments. Reliability and data integrity are the commonly emphasized requirements of spaceborne solid-state mass storage systems, because faults due to the harsh cosmic environments, such as extreme radiation, can be experienced throughout the mission. Acceptable dependability for these instruments has been achieved by using redundancy and repair. Reconfiguration (repair) of memory arrays using spare memory lines is the most common technique for reliability enhancement of memories with faults. Faulty cells in memory arrays are known to show spatial locality. This physical phenomenon is …

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The Mixed-Form Fast Multipole Algorithm For Broadband Electromagnetic Simulations, L. (Lijun) J. Jiang, W. C. Chew Dec 2005

The Mixed-Form Fast Multipole Algorithm For Broadband Electromagnetic Simulations, L. (Lijun) J. Jiang, W. C. Chew

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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The General Variational Formulas For Capacitance Parameter Extraction, W. C. Chew, L. (Lijun) J. Jiang Dec 2005

The General Variational Formulas For Capacitance Parameter Extraction, W. C. Chew, L. (Lijun) J. Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

To obtain second order accuracy using the first order data for the capacitance parameter extraction, a set of new generalized variational formulas are presented in this paper. They are complete since they are valid not only for self-capacitances, but also for mutual capacitances. A more general variational formula is derived to account for the asymmetrical elastance matrix case. By these novel formulas the computational accuracy can be significantly improved compared to the conventional direct capacitance extraction method. © 2005 IEEE.

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Crosstalk Analysis By Fast Computational Algorithms, Z. G. Qian, J. Xiong, L. Sun, I. T. Chiang, W. C. Chew, L. (Lijun) J. Jiang, Y. H. Chu Dec 2005

Crosstalk Analysis By Fast Computational Algorithms, Z. G. Qian, J. Xiong, L. Sun, I. T. Chiang, W. C. Chew, L. (Lijun) J. Jiang, Y. H. Chu

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we will present the use of low frequency fast algorithms for crosstalk analysis. Some criss-cross line structures are studied and time domain signals are demonstrated to ascertain crosstalk effect. ©2005 IEEE.

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A Mixed-Form Fast Multipole Algorithm, Li (Lijun) Jun Jiang, Weng Cho Chew Dec 2005

A Mixed-Form Fast Multipole Algorithm, Li (Lijun) Jun Jiang, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

The fast multipole algorithm manifests in two very different forms at low frequencies and at mid frequencies. Each can operate in their respective regimes, but are not tenable in the other regimes. The paper reports on a way to factorize the Green's function for fast algorithm using a mixed form. The low-frequency fast multipole algorithm (LF-FMA) will be used at low frequencies or the long-wavelength regime, and the multilevel fast multipole algorithm (MLFMA) will be used for the mid frequencies or the shorter-wavelength regime. For object modeling where both long-wavelength and wave physics are important, we propose a mixed-form fast …

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A Novel Method For Determination Of Dielectric Properties Of Materials Using A Combined Embedded Modulated Scattering And Near-Field Microwave Techniques-Part I: Forward Model, Dana M. Hughes, R. Zoughi Dec 2005

A Novel Method For Determination Of Dielectric Properties Of Materials Using A Combined Embedded Modulated Scattering And Near-Field Microwave Techniques-Part I: Forward Model, Dana M. Hughes, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The use of combined embedded modulated scattering technique and near-field microwave nondestructive testing techniques is investigated as a novel method for evaluating the dielectric properties of a material. The forward formulation for determining the reflection coefficient at the aperture of a waveguide radiating into a dielectric half-space in which a PIN diode-loaded dipole (i.e., modulated scattering technique probe) is embedded is presented. This formulation is based upon calculating the near-field coupling between the waveguide and the dipole as a mutual impedance.

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Solving Low Frequency Electromagnetic Problems With Fast Solvers, W. C. Chew, L. (Lijun) J. Jiang, Y. H. Chu, Y. A. Liu, M. K. Li, Z. G. Qian, J. Xiong, L. Sun Dec 2005

Solving Low Frequency Electromagnetic Problems With Fast Solvers, W. C. Chew, L. (Lijun) J. Jiang, Y. H. Chu, Y. A. Liu, M. K. Li, Z. G. Qian, J. Xiong, L. Sun

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Dynamic Growth Rates Of Microbial Populations In Activated Sludge Systems, Peter George Stroot, Pascal E. Saikaly, Daniel B. Oerther Dec 2005

Dynamic Growth Rates Of Microbial Populations In Activated Sludge Systems, Peter George Stroot, Pascal E. Saikaly, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Results of mathematical modeling and whole cell 16S ribosomal RNA-targeted fluorescence in situ hybridizations challenge the widely held perception that microbial populations in "steady-state" activated sludge systems share a common net growth rate that is proportional to the inverse of the mean cell residence time. Our results are significant because they encourage bioprocess engineers to appreciate the differences in growth physiology among individual microbial populations in complex mixed microbial communities such as suspended growth activated sludge bioreactor systems.

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Modeling Of Capacitor Impedance In Switching Converters, Jonathan W. Kimball, Philip T. Krein, Kevin R. Cahill Dec 2005

Modeling Of Capacitor Impedance In Switching Converters, Jonathan W. Kimball, Philip T. Krein, Kevin R. Cahill

Electrical and Computer Engineering Faculty Research & Creative Works

Switched capacitor (SC) converters are gaining acceptance as alternatives to traditional, inductor-based switching power converters. Proper design of SC converters requires an understanding of all loss sources and their impacts on circuit operation. In the present work, an equivalent resistance method is developed for analysis, and equivalent resistance formulae are presented for various modes of operation. Quasiresonant converters are explored and compared to standard SC converters. Comparisons to inductor-based switching power converters are made. A number of capacitor technologies are evaluated and compared for applications to both SC converters and inductor-based converters. The resulting model can be used to accurately …

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A Novel Method For Determination Of Dielectric Properties Of Materials Using A Combined Embedded Modulated Scattering And Near-Field Microwave Techniques-Part Ii: Dielectric Property Recalculation, R. Zoughi, Dana Hughes Dec 2005

A Novel Method For Determination Of Dielectric Properties Of Materials Using A Combined Embedded Modulated Scattering And Near-Field Microwave Techniques-Part Ii: Dielectric Property Recalculation, R. Zoughi, Dana Hughes

Electrical and Computer Engineering Faculty Research & Creative Works

The use of combined embedded modulated scattering technique and near-field microwave nondestructive testing techniques is investigated as a novel method for evaluating the dielectric properties of a material. The forward formulation for determining the reflection coefficient at the aperture of a waveguide radiating into a dielectric half-space in which a PIN diode-loaded dipole (i.e., modulated scattering technique probe) is embedded was presented in Part I of this paper. Here, in Part II, the recalculation of the dielectric properties, using the results of the forward model, is presented along with some associated experimental results.

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Percolation Quantum Phase Transitions In Diluted Magnets, Thomas Vojta, Jörg Schmalian Nov 2005

Percolation Quantum Phase Transitions In Diluted Magnets, Thomas Vojta, Jörg Schmalian

Physics Faculty Research & Creative Works

We show that the interplay of geometric criticality and quantum fluctuations leads to a novel universality class for the percolation quantum phase transition in diluted magnets. All critical exponents involving dynamical correlations are different from the classical percolation values, but in two dimensions they can nonetheless be determined exactly. We develop a complete scaling theory of this transition, and we relate it to recent experiments in La2Cu1-p(Zn,Mg)pO4. Our results are also relevant for disordered interacting boson systems.

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Marketing Military Service Benefits Segmentation Based On Generalized And Restricted Exchange, Caroline Fisher, Kimball P. Marshall Nov 2005

Marketing Military Service Benefits Segmentation Based On Generalized And Restricted Exchange, Caroline Fisher, Kimball P. Marshall

Business and Information Technology Faculty Research & Creative Works

Willingness to engage in exchange is based on desired benefits. In typical commercial transactions, restricted exchange benefits dominate. However, public policy, social marketing situations might require consideration of both restricted and generalized exchange benefits. Applying factor analysis, cluster analysis and cross-tabulation, this paper reports research that has successfully segmented a young adult target market regarding interest in military service based on considerations of generalized and restricted exchange motivations. This research contributes to a growing body of literature on generalized exchange as a key conceptual element for social marketing. Results demonstrate the utility of the generalized exchange concept in identifying amarket …

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Muscle Biochemistry And The Ontogeny Of Flight Capacity During Behavioral Development In The Honey Bee, Apis Mellifera, Stephen P. Roberts, Michelle M. Elekonich Nov 2005

Muscle Biochemistry And The Ontogeny Of Flight Capacity During Behavioral Development In The Honey Bee, Apis Mellifera, Stephen P. Roberts, Michelle M. Elekonich

Biological Sciences Faculty Research & Creative Works

A Fundamental Issue in Physiology and Behavior is Understanding the Functional and Genetic Mechanisms that Underlie Major Behavioral Shifts in Organisms as They Adopt New Environments or Life History Tactics. Such Transitions Are Common in Nature and Include the Age-Related Switch from Nest/hive Work to Foraging in Social Insects Such as Honeybees (Apis Mellifera). Because of their Experimental Tractability, Recently Sequenced Genome and Well Understood Biology, Honeybees Are an Ideal Model System for Integrating Molecular, Genetic, Physiological and Sociobiological Perspectives to Advance Understanding of Behavioral and Life History Transitions. When Honeybees (Apis Mellifera) Transition from Hive Work to Foraging, their …

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Neutron And Nuclear Inelastic Scattering Study Of The Einstein Oscillators In Ba-, Sr-, And Eu-Filled Germanium Clathrates, Raphaël P. Hermann, Werner Schweika, Olaf Leupold, Rudolf Rüffer, George S. Nolas, Fernande Grandjean, Gary J. Long Nov 2005

Neutron And Nuclear Inelastic Scattering Study Of The Einstein Oscillators In Ba-, Sr-, And Eu-Filled Germanium Clathrates, Raphaël P. Hermann, Werner Schweika, Olaf Leupold, Rudolf Rüffer, George S. Nolas, Fernande Grandjean, Gary J. Long

Chemistry Faculty Research & Creative Works

Inelastic neutron scattering measurements on Ba8Ga16Ge30 and Sr8Ga16Ge30 indicate the presence of soft local modes with Einstein oscillator energies of 4.9±0.1 and 4.4±0.1meV, modes which are associated with the lowest “rattling” mode of the Ba(B) and Sr(B) guests, respectively. Nuclear inelastic scattering measurements on Eu8Ga16Ge30 yield Einstein oscillator energies of between 3.0±0.3 and 7.5±1.2meV for the different modes of the Eu guests. Further, the resonant character of the measurements on Eu8Ga16Ge30 reveals, without question, that neither of the Eu guests …

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Solids Flow Mapping In A High Pressure Slurry Bubble Column, Novica Rados, Ashfaq Shaikh, Muthanna H. Al-Dahhan Nov 2005

Solids Flow Mapping In A High Pressure Slurry Bubble Column, Novica Rados, Ashfaq Shaikh, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Successful Design and Scale-Up of Slurry Bubble Column Reactors (SBCRs) Require Proper Understanding of How Operating Conditions Affect their Flow Behavior. Presently, there is Little Information on the Flow Dynamics of Solids (E.g., Distribution of Velocities and Turbulent Parameters) in Slurry Systems that Are Operated at Industrially Relevant Conditions of High Pressure, High Superficial Gas Velocities, and High Solids Loading. Computer Automated Radio Particle Tracking (CARPT) is Widely Recognized as One of a Few Techniques that Can Be Reliably Used Even in Highly Turbulent and Opaque Slurry Flows. This Work Utilizes an Improved CARPT Technique to Investigate the Effect of …

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Erratum: Publisher's Note: Calculation Of The One- And Two-Loop Lamb Shift For Arbitrary Excited Hydrogenic States (Physical Review Letters (2005) 95 (180404)), Andrzej Czarnecki, Ulrich D. Jentschura, Krzysztof Pachucki Nov 2005

Erratum: Publisher's Note: Calculation Of The One- And Two-Loop Lamb Shift For Arbitrary Excited Hydrogenic States (Physical Review Letters (2005) 95 (180404)), Andrzej Czarnecki, Ulrich D. Jentschura, Krzysztof Pachucki

Physics Faculty Research & Creative Works

No abstract provided.

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Compact Autonomous Completely Explosive Pulsed Power System Based On Transverse Shock Wave Demagnetization Of Nd₂Fe₁₄B And Magnetic Flux Compression, Sergey I. Shkuratov, Evgueni F. Talantsev, Jason Baird, Allen H. Stults, Larry L. Altgilbers Nov 2005

Compact Autonomous Completely Explosive Pulsed Power System Based On Transverse Shock Wave Demagnetization Of Nd₂Fe₁₄B And Magnetic Flux Compression, Sergey I. Shkuratov, Evgueni F. Talantsev, Jason Baird, Allen H. Stults, Larry L. Altgilbers

Mining Engineering Faculty Research & Creative Works

The design and performance of a compact autonomous completely explosive pulsed power system based on two physical effects, the transverse shock wave demagnetization of Nd2Fe14B high-energy hard ferromagnets and magnetic flux compression, are presented. A transverse shock wave ferromagnetic generator (FMG) served as a seed source, and a compact helical magnetic flux compression generator (FCG) was used as a pulsed power amplifier. Results of a theoretical and experimental study demonstrated reliable operation of the proposed FMG-FCG system. The methodology for analytical calculation of seed current amplitude is developed.

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Laser-Dressed Vacuum Polarization In A Coulomb Field, A. I. Milstein, Ivan S. Terekhov, Ulrich D. Jentschura, Christoph H. Keitel Nov 2005

Laser-Dressed Vacuum Polarization In A Coulomb Field, A. I. Milstein, Ivan S. Terekhov, Ulrich D. Jentschura, Christoph H. Keitel

Physics Faculty Research & Creative Works

We investigate quantum electrodynamic effects under the influence of an external, time-dependent electromagnetic field, which mediates dynamic modifications of the radiative corrections. Specifically, we consider the quantum electrodynamic vacuum-polarization tensor under the influence of two external background fields: a strong laser field and a nuclear Coulomb field. We calculate the charge and current densities induced by a nuclear Coulomb field in the presence of a laser field. We find the corresponding induced scalar and vector potentials. The induced potential, in first-order perturbation theory, leads to a correction to atomic energy levels. The external laser field breaks the rotational symmetry of …

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A Grasp For Unitary Space-Time Codes, Adam Panagos, Kurt Louis Kosbar Nov 2005

A Grasp For Unitary Space-Time Codes, Adam Panagos, Kurt Louis Kosbar

Electrical and Computer Engineering Faculty Research & Creative Works

Unitary space-time codes perform well at high signal-to-noise ratios on MIMO channels even when the propagation coefficients between transmitter and receiver are unknown. One method of constructing unitary space-time constellations uses a random search to find signal constellations that minimize the maximum pairwise correlation between transmitted signals. The work presented here uses a greedy randomized adaptive search procedure (GRASP) for finding good unitary space-time code constellations. Simulation results show that, on average, this technique finds codes with better correlation properties than the random search method. This new search procedure was also used to find signal constellations with better correlation properties …

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Precise Calculation Of Transition Frequencies Of Hydrogen And Deuterium Based On A Least-Squares Analysis, Ulrich D. Jentschura, Svetlana A. Kotochigova, Eric Olivier Le Bigot, Peter J. Mohr, Barry N. Taylor Oct 2005

Precise Calculation Of Transition Frequencies Of Hydrogen And Deuterium Based On A Least-Squares Analysis, Ulrich D. Jentschura, Svetlana A. Kotochigova, Eric Olivier Le Bigot, Peter J. Mohr, Barry N. Taylor

Physics Faculty Research & Creative Works

We combine a limited number of accurately measured transition frequencies in hydrogen and deuterium, recent quantum electrodynamics (QED) calculations, and, as an essential additional ingredient, a generalized least-squares analysis, to obtain precise and optimal predictions for hydrogen and deuterium transition frequencies. Some of the predicted transition frequencies have relative uncertainties more than an order of magnitude smaller than that of the g factor of the electron, which was previously the most accurate prediction of QED.

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