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Fourier Spectroscopy Of Ultrashort Laser Pulses, Scott D. Bergeson, Justin Peatross Sep 2006

Fourier Spectroscopy Of Ultrashort Laser Pulses, Scott D. Bergeson, Justin Peatross

Faculty Publications

We describe a Fourier-transform spectrometer appropriate for use in an undergraduate optics laboratory. The modular design, which uses off-the-shelf equipment, is suitable for determining the spectra of ultrashort pulsed and continuous light sources. The spectrometer does not require equal step sizes for the motion of the mirror. An algorithm interpolates the phase of both a reference and an unknown light beam at equal intervals before performing the Fourier transform. The interferometer scan and the phase and spectral analysis are performed in a few seconds, making the apparatus a useful tool for teaching concepts of temporal coherence and Fourier spectroscopy.

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Digital Roots Of Human Relations: Enabling Technologies For Family History And Genealogical Research, William A. Barrett Sep 2006

Digital Roots Of Human Relations: Enabling Technologies For Family History And Genealogical Research, William A. Barrett

Faculty Publications

Flowing out of a Computer Science research lab on the third floor of the Talmage Building is a wellspring of enabling technologies for family history and genealogical research. Here, computer science students, working under the direction of Dr. Tom Sederberg and Dr. Bill Barrett are creating software tools to help individuals with their family history research so that people everywhere can seek out their ancestors and perform vital ordinances in their behalf, as desired. These tools include visualization of an entire pedigree on a single (large) sheet of paper, the ability to automatically calculate if and how two or more …

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Fuzzy State Aggregation And Policy Hill Climbing For Stochastic Environments, Dean C. Wardell, Gilbert L. Peterson Sep 2006

Fuzzy State Aggregation And Policy Hill Climbing For Stochastic Environments, Dean C. Wardell, Gilbert L. Peterson

Faculty Publications

Reinforcement learning is one of the more attractive machine learning technologies, due to its unsupervised learning structure and ability to continually learn even as the operating environment changes. Additionally, by applying reinforcement learning to multiple cooperative software agents (a multi-agent system) not only allows each individual agent to learn from its own experience, but also opens up the opportunity for the individual agents to learn from the other agents in the system, thus accelerating the rate of learning. This research presents the novel use of fuzzy state aggregation, as the means of function approximation, combined with the fastest policy hill …

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Avoidance Of Future Singularities In Loop Quantum Cosmology, M. Sami, Parampreet Singh, Shinji Tsujikawa Aug 2006

Avoidance Of Future Singularities In Loop Quantum Cosmology, M. Sami, Parampreet Singh, Shinji Tsujikawa

Faculty Publications

We consider the fate of future singularities in the effective dynamics of loop quantum cosmology. Nonperturbative quantum geometric effects which lead to ρ2 modification of the Friedmann equation at high energies result in generic resolution of singularities whenever energy density ρ diverges at future singularities of Friedmann dynamics. Such quantum effects lead to the avoidance of a big rip, which is followed by a recollapsing universe stable against perturbations. Resolution of sudden singularity, the case when pressure diverges but energy density approaches a finite value depends on the ratio of the latter to a critical energy density of the order …

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Nonsingular Bouncing Universes In Loop Quantum Cosmology, Parampreet Singh, Kevin Vandersloot, G. V. Vereshchagin Aug 2006

Nonsingular Bouncing Universes In Loop Quantum Cosmology, Parampreet Singh, Kevin Vandersloot, G. V. Vereshchagin

Faculty Publications

Nonperturbative quantum geometric effects in loop quantum cosmology (LQC) predict a ρ2 modification to the Friedmann equation at high energies. The quadratic term is negative definite and can lead to generic bounces when the matter energy density becomes equal to a critical value of the order of the Planck density. The nonsingular bounce is achieved for arbitrary matter without violation of positive energy conditions. By performing a qualitative analysis we explore the nature of the bounce for inflationary and cyclic model potentials. For the former we show that inflationary trajectories are attractors of the dynamics after the bounce implying that …

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Global Behavior Of Integral Transforms, Jasson Vindas, Ricardo Estrada Aug 2006

Global Behavior Of Integral Transforms, Jasson Vindas, Ricardo Estrada

Faculty Publications

We obtain global estimates for various integral transforms of positive differentiable functions that satisfy inequalities of the type c1 f(x)/x≤-f (x)≤c2 f(x)/x, for x>0.

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Mesoscopic Domain Average Engineering Simulations Of Ferroelectric Perovskites Compared With Multidomain Group Theoretical Predictions, Brandon J. Keith, Dorian M. Hatch Aug 2006

Mesoscopic Domain Average Engineering Simulations Of Ferroelectric Perovskites Compared With Multidomain Group Theoretical Predictions, Brandon J. Keith, Dorian M. Hatch

Faculty Publications

Engineered, multidomain ferroelectrics are of current interest for mechatronic and optical applications. Previously [D. M. Hatch et al., J. Appl. Phys. 94, 5220 (2003)], we presented a set of tables/symmetry rules showing all possible domain average engineered multidomain structures arising from [100]-, [110]-, and [111]-ordering ferroelectric transitions from a Pm[overline 3]m perovskite structure. In this work we test those predictions against three-dimensional mesoscopic fast quench simulations under various electric/stress field combinations and find excellent agreement with multidomain group theory. These simulations use a Langevin strain-displacement/polarization evolution strategy and are important to developing processing conditions for materials with precise domain structures.

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Understanding Dc-Bias Sputtered Thorium Oxide Thin Films Useful In Euv Optics, William R. Evans, Sarah C. Barton, Michael Clemens, David D. Allred Aug 2006

Understanding Dc-Bias Sputtered Thorium Oxide Thin Films Useful In Euv Optics, William R. Evans, Sarah C. Barton, Michael Clemens, David D. Allred

Faculty Publications

We use spectroscopic ellipsometry to determine the optical constants of seven thin-film ThO2 samples deposited by radio-frequency sputtering, thickness ranging between 24 and 578 nm, for the spectral range of 1.2 to 6.5. We used a hollow-cathode light source and vacuum monochromator to measure constants at 10.2 eV. None of the deposition parameters studied including DC-bias voltages successfully increased the n of (that is, densify) thoria films. The value of n at 3.0 eV is 1.86 ± 0.04. We find compelling evidence to conclude that the direct bad gap is at ~5.9 eV, clarifying the results of others, some of …

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Tetrakis[2-(2-Pyridyl)Pyridinium] Tetra-Μ3-Iodo-Hexa-Μ2-Iodo-Dodecaiodohexabismuthate And Bis[Tris(2,2'-Bipyridine)Ruthenium(Ii)] Di-Μ4-Iodo-Octa-Μ2-Iodo-Dodecaiodohexabismuthate, Andrea M. Goforth, Meredith A. Tershansy, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye Aug 2006

Tetrakis[2-(2-Pyridyl)Pyridinium] Tetra-Μ3-Iodo-Hexa-Μ2-Iodo-Dodecaiodohexabismuthate And Bis[Tris(2,2'-Bipyridine)Ruthenium(Ii)] Di-Μ4-Iodo-Octa-Μ2-Iodo-Dodecaiodohexabismuthate, Andrea M. Goforth, Meredith A. Tershansy, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

Crystals of the title compounds were grown solvothermally in an ethanol-water solvent mixture using ruthenium triiodide, 2,2'-bipyridine and bismuth triiodide as starting materials. Tetrakis[2-(2-pyridyl)pyridinium] tetra-3-iodo-hexa-2-iodo-dodecaiodohexabismuthate, (C10H9N2)4[Bi6I22], crystallizes in the triclinic space group P and is the major reaction product. The asymmetric unit of this compound consists of half a centrosymmetric [Bi6I22]4- anion and two independent 2,2'-bipyridinium cations. The minor product of the reaction is bis[tris(2,2'-bipyridine)ruthenium(II)] di-4-iodo-octa-2-iodo-dodecaiodohexabismuthate, [Ru(C10H8N2)3] …

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Positive Current Correlations Associated With Super-Poissonian Shot Noise, Yuanzhen Chen, Richard A. Webb Aug 2006

Positive Current Correlations Associated With Super-Poissonian Shot Noise, Yuanzhen Chen, Richard A. Webb

Faculty Publications

We report on shot noise cross spectrum measurements in a beam splitter configuration. Electrons tunneling through potential barriers are incident on a beam splitter and scattered into two separate channels. Such a partition process introduces correlations between the fluctuations of the two currents. Our work has confirmed that the generally expected negative correlations resulted from sub-Poissonian electron sources. More interestingly, positive cross correlations associated with barriers exhibiting super-Poissonian shot noise have also been observed. We have found that both positive and negative correlations can be related to the noise properties of the electron source.

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Methane Conversion In Pulsed Corona Discharge Reactors, Morris D. Argyle, Gui-Bing Zhao, Sanil John, Ji-Jun Zhang, Linna Wang, Suresh S. Muknahallipatna, Jerry C. Hamann, John F. Ackerman, Ovid A. Plumb Aug 2006

Methane Conversion In Pulsed Corona Discharge Reactors, Morris D. Argyle, Gui-Bing Zhao, Sanil John, Ji-Jun Zhang, Linna Wang, Suresh S. Muknahallipatna, Jerry C. Hamann, John F. Ackerman, Ovid A. Plumb

Faculty Publications

This work reports the effect of capacitance, cathode material, gas flow rate and specific energy input on methane conversion, energy efficiency and product selectivity in a co-axial cylinder pulsed corona discharge reactor. Ethan and acetylene appear to be formed from dimerization of CH3 radicals and CH radicals, respectively, while ethylene is formed mainly from the dehydrogenation of ethane. At a given power input, low capacitance with high pulse frequency results in higher methane conversion and energy efficiency than operation at high capacitance with low pulse frequency. Platinum coated stainless steel cathodes slightly enhance methane conversion relative to stainless steel cathodes, …

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A Compact Digitally Controlled Fuel Cell/Battery Hybrid Power Source, Zhenhua Jiang, Roger A. Dougal Aug 2006

A Compact Digitally Controlled Fuel Cell/Battery Hybrid Power Source, Zhenhua Jiang, Roger A. Dougal

Faculty Publications

A compact digitally controlled fuel cell/battery hybrid power source is presented in this paper. The hybrid power source composed of fuel cells and batteries provides a much higher peak power than each component alone while preserving high energy density, which is important and desirable for many modern electronic devices, through an appropriately controlled dc/dc power converter that handles the power flow shared by the fuel cell and the battery. Rather than being controlled to serve only as a voltage or current regulator, the power converter is regulated to balance the power flow to satisfy the load requirements while ensuring the …

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Integrating Software Into Pra: A Software-Related Failure Mode Taxonomy, Bin Li, Ming Li, Ken Chen, Carol Smidts Aug 2006

Integrating Software Into Pra: A Software-Related Failure Mode Taxonomy, Bin Li, Ming Li, Ken Chen, Carol Smidts

Faculty Publications

Probabilistic risk assessment is a methodology to assess the probability of failure or success of a mission. Results provided by the risk assessment methodology are used to make decisions concerning choice of upgrades, scheduling of maintenance, decision to launch, etc. However, current PRA neglects the contribution of software to the risk of failure of the mission. Our research has developed a methodology to account for the impact of software to system failure. This article focuses on an element of the approach: a comprehensive taxonomy of software-related failure modes. Application of the taxonomy is discussed in this article. A validation of …

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Reciprocity For Multirestricted Stirling Numbers, Ji Young Choi, Ling Long, Siu Hung Ng, Jonathan Smith Aug 2006

Reciprocity For Multirestricted Stirling Numbers, Ji Young Choi, Ling Long, Siu Hung Ng, Jonathan Smith

Faculty Publications

Multirestricted Stirling numbers of the second kind count the number of partitions of a given set into a given number of parts, each part being restricted to at most a fixed number of elements. Multirestricted numbers of the first kind are then defined as elements of the matrix inverse to the matrix of corresponding multirestricted numbers of the second kind. The anomalous sign behavior of these latter numbers makes them impervious to combinatorial analysis. In answer to a conjecture that has remained open for several years, we derive a reciprocity law for multirestricted Stirling numbers using algebraic techniques based on …

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Effective Hamiltonians In Quantum Physics: Resonances And Geometric Phase, A. R.P. Rau, D. Uskov Aug 2006

Effective Hamiltonians In Quantum Physics: Resonances And Geometric Phase, A. R.P. Rau, D. Uskov

Faculty Publications

Effective Hamiltonians are often used in quantum physics, both in time-dependent and time-independent contexts. Analogies are drawn between the two usages, the discussion framed particularly for the geometric phase of a time-dependent Hamiltonian and for resonances as stationary states of a time-independent Hamiltonian. © 2006 The Royal Swedish Academy of Sciences.

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Self-Assembled Composite Nano-/Micronecklaces With Sio2 Beads In Boron Strings, Hai Ni, Xiaodong Li Jul 2006

Self-Assembled Composite Nano-/Micronecklaces With Sio2 Beads In Boron Strings, Hai Ni, Xiaodong Li

Faculty Publications

Nano-/micronecklaces with SiO2 beads in boron strings were synthesized by simply sublimating the desired powders in a sealed quartz tube at high temperature. The boron strings have a rectangular cross section with width varying from 80to1000nm while the SiO2 beads bear either spindle or spherical shape with a size ranging from 100nmto5μm. The spacing between the SiO2 beads is uniform in each boron string. Both the boron strings and the SiO2 beads are amorphous and free of defects. The supersaturated vapors of silicon and oxygen induced the SiO2 bead formation.

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A Constructive Incremental Learning Algorithm For Binary Classification Tasks, Christophe G. Giraud-Carrier, Tony R. Martinez Jul 2006

A Constructive Incremental Learning Algorithm For Binary Classification Tasks, Christophe G. Giraud-Carrier, Tony R. Martinez

Faculty Publications

This paper presents i-AA1*, a constructive, incremental learning algorithm for a special class of weightless, self-organizing networks. In i-AA1*, learning consists of adapting the nodes’ functions and the network’s overall topology as each new training pattern is presented. Provided the training data is consistent, computational complexity is low and prior factual knowledge may be used to “prime” the network and improve its predictive accuracy. Empirical generalization results on both toy problems and more realistic tasks demonstrate promise.

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Spectroscopy Of Grb 051111 At Z = 1.54948: Kinematics And Elemental Abundances Of The Grb Environment And Host Galaxy, B. E. Penprase, E. Berger, D. B. Fox, S. R. Kulkarni, S. Kadish, L. Kerber, E. Ofek, M. Kasliwal, G. Hill, B. Schaefer, M. Reed Jul 2006

Spectroscopy Of Grb 051111 At Z = 1.54948: Kinematics And Elemental Abundances Of The Grb Environment And Host Galaxy, B. E. Penprase, E. Berger, D. B. Fox, S. R. Kulkarni, S. Kadish, L. Kerber, E. Ofek, M. Kasliwal, G. Hill, B. Schaefer, M. Reed

Faculty Publications

We present a high-resolution, high S/N optical spectrum of the afterglow of GRB 051111 obtained with the HIRES spectrograph on the Keck I 10 m telescope. The spectrum exhibits three redshitted absorption systems with the highest, at z = 1.54948, arising in the GRB host galaxy. While the Lya feature is outside the range of our spectrum, the high column density of weakly depleted Zn suggests that the host is a damped Lyα system with N(H I) ≲ 1021 (Z/Z⊙)-1. The bulk of the gas (>80%) is confined to a narrow velocity range of |v| < 30 km s-1, exhibiting strong dust depletion of refractory elements such as Fe and Cr. The depletion pattern is similar to that observed in warm disk clouds of the Milky Way. We also detect absorption from all ground-level fine-structure states of Fe II, the first such example in a QSO-DLA system or GRB-absorption spectrum, which indicate conditions that are consistent with the "warm disk" depletion pattern. The absorption profiles of Fe II and Mg n extend over several hundred km s -1, with a depletion pattern that more closely resembles that of QSO-DLA systems, suggesting that the sight line to GRB 051111 probes the halo of the host galaxy in addition to the dense disk. Thus, detailed diagnostics of the interstellar medium of GRB host galaxies continue to provide insight into regions that are generally missed in quasar surveys. © 2006. The American Astronomical Society. All rights reserved.

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Magnetic Instabilities And Phase Diagram Of The Double-Exchange Model In Infinite Dimensions, R. S. Fishman, F. Popescu, G. Alvarez, J. Moreno, Th Maier, M. Jarrell Jul 2006

Magnetic Instabilities And Phase Diagram Of The Double-Exchange Model In Infinite Dimensions, R. S. Fishman, F. Popescu, G. Alvarez, J. Moreno, Th Maier, M. Jarrell

Faculty Publications

Dynamical mean-field theory is used to study the magnetic instabilities and phase diagram of the double-exchange (DE) model with Hund's coupling J H > 0 in infinite dimensions. In addition to ferromagnetic (FM) and antiferromagnetic (AF) phases, the DE model also supports a broad class of short-range ordered (SRO) states with extensive entropy and short-range magnetic order. For any site on the Bethe lattice, the correlation parameter q of an SRO state is given by the average q = 〈sin2(θ i/2)〉, where θi is the angle between any spin and its neighbours. Unlike the FM (q = 0) and AF (q …

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The Effect Of Protein Dielectric Coefficient On The Ionic Selectivity Of A Calcium Channel, Douglas Henderson, Dezso Boda, Monika Valisko, Bob Eisenberg, Wolfgang Nonner, Dirk Gillespie Jul 2006

The Effect Of Protein Dielectric Coefficient On The Ionic Selectivity Of A Calcium Channel, Douglas Henderson, Dezso Boda, Monika Valisko, Bob Eisenberg, Wolfgang Nonner, Dirk Gillespie

Faculty Publications

Calcium-selective ion channels are known to have carboxylate-rich selectivity filters, a common motif that is primarily responsible for their high Ca2+ affinity. Different Ca2+ affinities ranging from micromolar (the L-type Ca channel) to millimolar (the ryanodine receptor channel) are closely related to the different physiological functions of these channels. To understand the physical mechanism for this range of affinities given similar amino acids in their selectivity filters, we use grand canonical Monte Carlo simulations to assess the binding of monovalent and divalent ions in the selectivity filter of a model Ca channel. We use a reduced model where the electrolyte …

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Particle Swarm Optimization In Dynamic Pricing, Christopher K. Monson, Patrick B. Mullen, Kevin Seppi, Sean C. Warnick Jul 2006

Particle Swarm Optimization In Dynamic Pricing, Christopher K. Monson, Patrick B. Mullen, Kevin Seppi, Sean C. Warnick

Faculty Publications

Dynamic pricing is a real-time machine learning problem with scarce prior data and a concrete learning cost. While the Kalman Filter can be employed to track hidden demand parameters and extensions to it can facilitate exploration for faster learning, the exploratory nature of Particle Swarm Optimization makes it a natural choice for the dynamic pricing problem. We compare both the Kalman Filter and existing particle swarm adaptations for dynamic and/or noisy environments with a novel approach that time-decays each particle's previous best value; this new strategy provides more graceful and effective transitions between exploitation and exploration, a necessity in the …

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Cooperation-Based Clustering For Profit-Maximizing Organizational Design, Christophe G. Giraud-Carrier, Kevin Seppi, Nghia Tran, Sean C. Warnick Jul 2006

Cooperation-Based Clustering For Profit-Maximizing Organizational Design, Christophe G. Giraud-Carrier, Kevin Seppi, Nghia Tran, Sean C. Warnick

Faculty Publications

This paper shows how the notion of value of cooperation, a measure of the percentage of a firm’s profits due strictly to the cooperative effects among the goods it sells, can be used to analyze the relative economic advantage afforded by various organizational structures. The value of cooperation is computed from transactions data by solving a regression problem to fit the parameters of the consumer demand function, and then simulating the resulting profit-maximizing dynamic system under various organizational structures. A hierarchical agglomerative clustering algorithm can be applied to reveal the optimal organizational substructure.

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Quantum Nature Of The Big Bang: An Analytical And Numerical Investigation, Abhay Ashtekar, Tomasz Pawlowski, Parampreet Singh Jul 2006

Quantum Nature Of The Big Bang: An Analytical And Numerical Investigation, Abhay Ashtekar, Tomasz Pawlowski, Parampreet Singh

Faculty Publications

Analytical and numerical methods are developed to analyze the quantum nature of the big bang in the setting of loop quantum cosmology. They enable one to explore the effects of quantum geometry both on the gravitational and matter sectors and significantly extend the known results on the resolution of the big bang singularity. Specifically, the following results are established for the homogeneous isotropic model with a massless scalar field: (i) the scalar field is shown to serve as an internal clock, thereby providing a detailed realization of the "emergent time" idea; (ii) the physical Hilbert space, Dirac observables, and semiclassical …

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Incorporating Policymaker Costs And Political Competition Into Rent-Seeking Games, R. Kenneth Godwin, Edward J. Lopez, Barry J. Seldon Jul 2006

Incorporating Policymaker Costs And Political Competition Into Rent-Seeking Games, R. Kenneth Godwin, Edward J. Lopez, Barry J. Seldon

Faculty Publications

We incorporate policymaker costs of supplying rents and variable intensities of competition among rent seekers into the standard rent-seeking game. By incorporating these aspects, the game has greater verisimilitude to the lobbying process. The first aspect captures the fact that in rent-seeking contests there is a positive probability that neither firm will obtain the rent. The second aspect captures the fact that firms seeking different rents still must compete for policymakers' resources. We find that lobbying expenditures, rent-seeking profits, and rent dissipation depend on the intensity of competition and the value of the rent relative to policymaker costs. For example, …

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Learning A Rendezvous Task With Dynamic Joint Action Perception, Nancy Fulda, Dan A. Ventura Jul 2006

Learning A Rendezvous Task With Dynamic Joint Action Perception, Nancy Fulda, Dan A. Ventura

Faculty Publications

Groups of reinforcement learning agents interacting in a common environment often fail to learn optimal behaviors. Poor performance is particularly common in environments where agents must coordinate with each other to receive rewards and where failed coordination attempts are penalized. This paper studies the effectiveness of the Dynamic Joint Action Perception (DJAP) algorithm on a grid-world rendezvous task with this characteristic. The effects of learning rate, exploration strategy, and training time on algorithm effectiveness are discussed. An analysis of the types of tasks for which DJAP learning is appropriate is also presented.

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Preparing More Effective Liquid State Machines Using Hebbian Learning, David Norton, Dan A. Ventura Jul 2006

Preparing More Effective Liquid State Machines Using Hebbian Learning, David Norton, Dan A. Ventura

Faculty Publications

In Liquid State Machines, separation is a critical attribute of the liquid—which is traditionally not trained. The effects of using Hebbian learning in the liquid to improve separation are investigated in this paper. When presented with random input, Hebbian learning does not dramatically change separation. However, Hebbian learning does improve separation when presented with real-world speech data.

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Spatiotemporal Pattern Recognition Via Liquid State Machines, Eric Goodman, Dan A. Ventura Jul 2006

Spatiotemporal Pattern Recognition Via Liquid State Machines, Eric Goodman, Dan A. Ventura

Faculty Publications

The applicability of complex networks of spiking neurons as a general purpose machine learning technique remains open. Building on previous work using macroscopic exploration of the parameter space of an (artificial) neural microcircuit, we investigate the possibility of using a liquid state machine to solve two real-world problems: stockpile surveillance signal alignment and spoken phoneme recognition.

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Learning Quantum Operators From Quantum State Pairs, Neil Toronto, Dan A. Ventura Jul 2006

Learning Quantum Operators From Quantum State Pairs, Neil Toronto, Dan A. Ventura

Faculty Publications

Developing quantum algorithms has proven to be very difficult. In this paper, the concept of using classical machine learning techniques to derive quantum operators from examples is presented. A gradient descent algorithm for learning unitary operators from quantum state pairs is developed as a starting point to aid in developing quantum algorithms. The algorithm is used to learn the quantum Fourier transform, an underconstrained two-bit function, and Grover’s iterate.

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Decentralized Cooperative Aerial Surveillance Using Fixed-Wing Miniature Uavs, Randal Beard, Derek Kingston, Timothy W. Mclain, Derek Nelson Jul 2006

Decentralized Cooperative Aerial Surveillance Using Fixed-Wing Miniature Uavs, Randal Beard, Derek Kingston, Timothy W. Mclain, Derek Nelson

Faculty Publications

Numerous applications require aerial surveillance. Civilian applications include monitoring forest fires, oil fields and pipelines, and tracking wildlife. Applications to homeland security include border patrol and monitoring the perimeter of nuclear power plants. Military applications are numerous. The current approach to these applications is to use a single manned vehicle for surveillance. However, manned vehicles are typically large and expensive. In addition, hazardous environments and operator fatigue can potentially threaten the life of the pilot. Therefore, there is a critical need for automating aerial surveillance using unmanned air vehicles (UAVs). This paper gives an overview of a cooperative control strategy …

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Semiclassical Nonadiabatic Dynamics Based On Quantum Trajectories For The O(3P,1D)+H2 System, Sophya Garashchuk, Vitaly A. Rassolov, George C. Schatz Jun 2006

Semiclassical Nonadiabatic Dynamics Based On Quantum Trajectories For The O(3P,1D)+H2 System, Sophya Garashchuk, Vitaly A. Rassolov, George C. Schatz

Faculty Publications

The O(3P,1D)+H2→OH+H reaction is studied using trajectory dynamics within the approximate quantum potential approach. Calculations of the wave-packet reaction probabilities are performed for four coupled electronic states for total angular momentum J = 0 using a mixed coordinate/polar representation of the wave function. Semiclassical dynamics is based on a single set of trajectories evolving on an effective potential-energy surface and in the presence of the approximate quantum potential. Population functions associated with each trajectory are computed for each electronic state. The effective surface is a linear combination of the electronic states with the contributions …

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