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2000

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Articles 1 - 30 of 362

Full-Text Articles in Physics

Unitarized Pseudoscalar Meson Scattering Amplitudes In Three Flavor Linear Sigma Models, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Sherif Moussa, Salah Nasri Dec 2000

Unitarized Pseudoscalar Meson Scattering Amplitudes In Three Flavor Linear Sigma Models, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Sherif Moussa, Salah Nasri

Physics - All Scholarship

The three flavor linear sigma model is studied as a ``toy model'' for understanding the role of possible light scalar mesons in the \pi \pi, \pi K and \pi \eta scattering channels. The approach involves computing the tree level partial wave amplitude for each channel and unitarizing by a simple K-matrix prescription which does not introduce any new parameters. If the renormalizable version of the model is used there is only one free parameter. While this highly constrained version has the right general structure to explain \pi \pi scatteirng, it is ``not quite'' right. A reasonable fit can be made …

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Phase Diagram Of Three-Dimensional Dynamical Triangulations With A Boundary, Simon Catterall, Simeon Warner, Ray Renken Dec 2000

Phase Diagram Of Three-Dimensional Dynamical Triangulations With A Boundary, Simon Catterall, Simeon Warner, Ray Renken

Physics - All Scholarship

We use Monte Carlo simulation to study the phase diagram of three-dimensional dynamical triangulations with a boundary. Three phases are indentified and characterized. One of these phases is a new, boundary dominated phase; a simple argument is presented to explain its existence. First-order transitions are shown to occur along the critical lines separating phases.

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Higher Twist Contributions To R-Hadron Phenomenology In The Light Gluino Scenario, Thomas D. Gutierrez, R. Vogt, J. F. Gunion Dec 2000

Higher Twist Contributions To R-Hadron Phenomenology In The Light Gluino Scenario, Thomas D. Gutierrez, R. Vogt, J. F. Gunion

Physics

The open light gluino window allows non-trivial higher-twist gluino contributions to the proton wave function. Using a two-component model originally developed for charm hadroproduction, higher-twist intrinsic gluino contributions to final-state R-hadron formation are shown to enhance leading-twist production in the forward xnF region. We calculate R-hadron production at Pnlab=800 GeV in pp, pBe, and pCu interactions with light gluino masses of 1.2, 1.5, 3.5, and 5.0 GeV.

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Electrons In Image States Near Roughened Metal Surfaces, Brian K. Clark, Brian W. Gregory, Jean M. Standard Dec 2000

Electrons In Image States Near Roughened Metal Surfaces, Brian K. Clark, Brian W. Gregory, Jean M. Standard

Faculty Publications – Chemistry

Electrons near roughened Ag and Au surfaces with chemisorbed dielectric overlayers of alkanethiol or alkaneselenol self-assembled monolayers are shown to move within the sulfur or selenium head-group layer on the metal terraces. The electrons exist in image states with respect to Ag or Au step edges. There is no substantial image force between the electrons and the terraces.

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A Two-Chain Path Integral Model Of Positronium, L. Larrimore, R. N. Mcfarland, P. A. Sterne, Amy Lisa Graves Dec 2000

A Two-Chain Path Integral Model Of Positronium, L. Larrimore, R. N. Mcfarland, P. A. Sterne, Amy Lisa Graves

Physics & Astronomy Faculty Works

We have used a path integral Monte Carlo technique to simulate positronium (Ps) in a cavity. The primitive propagator is used, with a pair of interacting chains representing the positron and electron. We calculate the energy and radial distribution function for Ps enclosed in a hard, spherical cavity, and the polarizability of the model Ps in the presence of an electrostatic field. We find that the positron distribution near the hard wall differs significantly from that for a single particle in a hard cavity. This leads to systematic deviations from predictions of free-volume models which treat Ps as an effective, …

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Thermoelectric Single-Photon Detectors For X-Ray/Uv Radiation, G. G. Fritz, K. S. Wood, D. Van Vechten, A. L. Gyulamiryan, A. S. Kuzanyan, N. J. Giordano, T. M. Jacobs, H.-D. Wu, J. S. Horwitz, Armen Gulian Dec 2000

Thermoelectric Single-Photon Detectors For X-Ray/Uv Radiation, G. G. Fritz, K. S. Wood, D. Van Vechten, A. L. Gyulamiryan, A. S. Kuzanyan, N. J. Giordano, T. M. Jacobs, H.-D. Wu, J. S. Horwitz, Armen Gulian

Mathematics, Physics, and Computer Science Faculty Articles and Research

A feasibility study of megapixel microcalorimeter arrays, based on thermoelectric energy to voltage conversion and digital superconducting readout, is presented. The design concept originated from the philosophy of employing the simplest principles at the single-pixel level to enable large arrays without sacrificing energy resolution, fast operation speed, and quantum efficiency. Initial experimental tests confirm the basic predictions of theory, and show no major obstacle in achieving the desired characteristics.

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Master Equation For Hydrogen Recombination On Grain Surfaces, Gianfranco Vidali, Ofer Biham, Itay Furman, Valerio Pirronello Dec 2000

Master Equation For Hydrogen Recombination On Grain Surfaces, Gianfranco Vidali, Ofer Biham, Itay Furman, Valerio Pirronello

Physics - All Scholarship

Recent experimental results on the formation of molecular hydrogen on astrophysically relevant surfaces under conditions similar to those encountered in the interstellar medium provided useful quantitative information about these processes. Rate equation analysis of experiments on olivine and amorphous carbon surfaces provided the activation energy barriers for the diffusion and desorption processes relevant to hydrogen recombination on these surfaces. However, the suitability of rate equations for the simulation of hydrogen recombination on interstellar grains, where there might be very few atoms on a grain at any given time, has been questioned. To resolve this problem, we introduce a master equation …

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Cross Section For B-Jet Production In P̅P Collisions At √S = 1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration Dec 2000

Cross Section For B-Jet Production In P̅P Collisions At √S = 1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

Bottom-quark production in p̅p collisions at √s = 1.8 TeV is studied with 5 pb-1 of data collected in 1995 by the D0 detector at the Fermilab Tevatron Collider. The differential production cross section for b jets in the central rapidity region (∣yb∣< 1) as a function of jet transverse energy is extracted from a muon-tagged jet sample. Within experimental and theoretical uncertainties, D0 results are found to be higher than, but compatible with, next-to-leading-order QCD predictions.

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Measurement Of The W Boson Mass Using Large Rapidity Electrons, B. Abbott, Gregory R. Snow, D0 Collaboration Dec 2000

Measurement Of The W Boson Mass Using Large Rapidity Electrons, B. Abbott, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We present a measurement of the W boson mass using data collected by the DØ. experiment at the Fermilab Tevatron during 1994–1995. We identify W bosons by their decays to en final states where the electron is detected in a forward calorimeter. We extract the W boson mass MW by fitting the transverse mass and transverse electron and neutrino momentum spectra from a sample of 11 089 W→eν decay candidates. We use a sample of 1687 dielectron events, mostly due toZ→ee decays, to constrain our model of the detector response. Using the forward …

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Low-Frequency Crossover Of The Fractional Power-Law Conductivity In Srruo3, J. S. Dodge, Christopher P. Weber, J. Corson, J. Orenstein, Z. Schlesinger, J. W. Reiner, M. R. Beasley Dec 2000

Low-Frequency Crossover Of The Fractional Power-Law Conductivity In Srruo3, J. S. Dodge, Christopher P. Weber, J. Corson, J. Orenstein, Z. Schlesinger, J. W. Reiner, M. R. Beasley

Physics

We combine the results of terahertz time-domain spectroscopy with far-infrared transmission and reflectivity to obtain the conductivity of SrRuO 3 over an unprecedented continuous range in frequency, allowing us to characterize the approach to zero frequency as a function of temperature. We show that the conductivity follows a simple phenomenological form, with an analytic structure fundamentally different from that predicted by the standard theory of metals.

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Ga-Doped Zno Films Grown On Gan Templates By Plasma-Assisted Molecular-Beam Epitaxy, H. J. Ko, Yanfang Chen, S. K. Hong, H. Wenisch, T. Yao, David C. Look Dec 2000

Ga-Doped Zno Films Grown On Gan Templates By Plasma-Assisted Molecular-Beam Epitaxy, H. J. Ko, Yanfang Chen, S. K. Hong, H. Wenisch, T. Yao, David C. Look

Physics Faculty Publications

We have investigated the structural and optical properties of Ga-doped ZnO films grown on GaN templates by plasma-assisted molecular-beam epitaxy. The carrier concentration in Ga-doped ZnO films can be controlled from 1.33×1018/cm3 to 1.13×1020/cm3. Despite high Ga incorporation, the linewidth of (0002) ω-rocking curves of Ga-doped ZnO films still lies in the range from 5 to 15 arc min. Photoluminescence (PL) spectra of Ga-doped ZnO films show dominant near-bandedge emission with negligibly weak deep-level emission, independent of carrier concentration. The PL spectrum exhibits a new emission line at 3.358 eV, which corresponds to …

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On The Persistence Of Small Regions Of Vorticity In The Protoplanetary Nebula, S. S. Davis, D. P. Sheehan, J. N. Cuzzi Dec 2000

On The Persistence Of Small Regions Of Vorticity In The Protoplanetary Nebula, S. S. Davis, D. P. Sheehan, J. N. Cuzzi

Physics and Biophysics: Faculty Scholarship

The fate of small regions of vorticity in a barotropic model of the protoplanetary nebula is investigated over thousands of years using a finite difference model. It is found that the coherence time for a small island of vorticity depends on its size, strength, orientation, and radial location in the nebula. Anticyclonic vorticity retains its coherence for longer times than cyclonic vorticity due to favorable interactions with the Keplerian shear flow. Rossby waves are generated as a result of mean vorticity gradients across the disk. The two-dimensional nebula evolves from discrete vortices into an axisymmetric flow consisting of small-amplitude vortex …

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Stabilization Of Bound State Decay In An Intense Monochromatic High-Frequency Field, N. L. Manakov, M. V. Frolov, Bogdan Borca, Anthony F. Starace Dec 2000

Stabilization Of Bound State Decay In An Intense Monochromatic High-Frequency Field, N. L. Manakov, M. V. Frolov, Bogdan Borca, Anthony F. Starace

Anthony F. Starace Publications

The formalism of complex quasienergies is used for exact calculation of the field-dependent decay rate for a weakly bound particle (in the model of a three-dimensional zero-range potential) in a strong monochromatic laser field. It is shown that the adiabatic (quasistationary) stabilization regime in this model occurs at frequencies ω exceeding the binding energy and only in a limited intensity range. A simple estimate is obtained for the critical field of stabilization breakdown. The effect may be observed for the decay of H– ions in the field of a neodymium laser of femtosecond duration.

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Surface Segregation And Restructuring Of Colossal-Magnetoresistant Manganese Perovskites La0.65Sr0.35Mno3, Hani Dulli, Peter A. Dowben, Sy-Hwang Liou, E. Ward Plummer Dec 2000

Surface Segregation And Restructuring Of Colossal-Magnetoresistant Manganese Perovskites La0.65Sr0.35Mno3, Hani Dulli, Peter A. Dowben, Sy-Hwang Liou, E. Ward Plummer

Department of Physics and Astronomy: Faculty Publications

We have investigated the surface chemical composition of crystalline films of La0.65Sr0.35MnO3 by angle-resolved x-ray photoelectron spectroscopy. The surface composition was found to be significantly different from that of the bulk because of an appreciable Sr segregation. Furthermore, our study suggests that this Sr segregation has caused a major restructuring of the surface region characterized by the formation of a Ruddlesden-Popper phase (La,Sr)n+1MnnO3n+1 with n = 1. Segregation and restructuring in the surface region should be common in these doped perovskites and will have a profound impact on the electronic …

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Measurement Of The Decay Amplitudes Of B0 → J/ΨK*0 And BS0 → J/Ψφ Decays, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Nov 2000

Measurement Of The Decay Amplitudes Of B0 → J/ΨK*0 And BS0 → J/Ψφ Decays, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

An angular analysis of B0 → J/ψK*0and Bs0 → J/ψφ has been used to determine the decay amplitudes with parity-even longitudinal (A0) and transverse (A║) polarization and parity-odd transverse (A┴) polarization. The measurements are based on 190 B0 and 40Bs0candidates obtained from 89 pb-1 of p̅p collisions at the Fermilab Tevatron. The longitudinal decay amplitude dominates with |A0|2= 0.59 ± 0.06 ± 0.01 for B0 and |A0|2 …

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The Dissociative Recombination Of The Helium Molecular Ion The Observed Final Products, Luminita Coman Nov 2000

The Dissociative Recombination Of The Helium Molecular Ion The Observed Final Products, Luminita Coman

FIU Electronic Theses and Dissertations

Dissociative recombination reaction has been studied theoretically and experimentally for about four decades. Because of the complexity of this process there is not yet a definite agreement between theory and experiment. In this work, dissociative recombination (DR) of helium molecular ion in thermal plasma was studied using Time of Flight (TOF) spectroscopy. This method allowed the identification of the final atom states products of DR. We found the following final products of the DR of the molecular ion: He(3S; 1s3s), He(1S; 1s3s), He(3P; 1s3p), He(3D; 1s3d), He(1D; 1s3d), He(1 …

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The Hall A Aerogel Čerenkov Detector, Marius Coman Nov 2000

The Hall A Aerogel Čerenkov Detector, Marius Coman

FIU Electronic Theses and Dissertations

The efficiency of the Aerogel Čerenkov detector for detecting particles having velocities greater than the speed of light in the aerogel media and the yield for rejecting particles having subthreshold velocities - smaller than the speed of light in the interaction media - was studied and is presented. The efficiency/inefficiency determination of the Aerogel Čerenkov detector consists of calculating the probabilities that a particle having a velocity above/below threshold generates a photoelectron in the aerogel block. The efficiency is determined using the normalised pulse height distribution of the photoelectrons. The Aerogel Čerenkov detector will play a key role in particle …

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A Discotic Disguised As A Smectic: A Hybrid Columnar Bragg Glass, Karl Saunders, Leo Radzihovsky, John Toner Nov 2000

A Discotic Disguised As A Smectic: A Hybrid Columnar Bragg Glass, Karl Saunders, Leo Radzihovsky, John Toner

Physics

We show that discotics, lying deep in the columnar phase, can exhibit an x-ray scattering pattern which mimics that of a somewhat unusual smectic liquid crystal. This exotic, new glassy phase of columnar liquid crystals, which we call a “hybrid columnar Bragg glass,” can be achieved by confining a columnar liquid crystal in an anisotropic random environment of, e.g., strained aerogel. Long-ranged orientational order in this phase makes single-domain x-ray scattering possible, from which a wealth of information could be extracted. We give detailed quantitative predictions for the scattering pattern in addition to exponents characterizing anomalous elasticity of the system.

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Photonuclear Physics: Laser Splits Atom, Donald Umstadter Nov 2000

Photonuclear Physics: Laser Splits Atom, Donald Umstadter

Donald Umstadter Publications

Lasers have become ubiquitous, being used in everything from a bar-code reader to a compact disk player. Who would have thought that they might be used to split the atom? A few scientists proposed to do just that more that a decade ago. But accomplishing it in the laboratory had to await the maturity of new technology, which enabled the construction of the world's most powerful lasers at the Lawrence Livermore National Laboratory in the United States and at the Rutherford Appleton Laboratory in the United Kingdom. Now two independent research teams have used these lasers to split the uranium …

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Dijet Production By Double Pomeron Exchange At The Fermilab Tevatron, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Nov 2000

Dijet Production By Double Pomeron Exchange At The Fermilab Tevatron, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We report the first observation of dijet events with a double Pomeron exchange topology produced in p̅p collisions at √s= 1800 GeV. The events are characterized by a leading antiproton, two jets in the central pseudorapidity region, and a large rapidity gap on the outgoing proton side. We present results on jet kinematics and production rates, compare them with corresponding results from single diffractive and inclusive dijet production, and test factorization.

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Continuum Pumping Of [Fe Ii] In The Orion Nebula, E. M. Verner, D. A. Verner, J. A. Baldwin, Gary J. Ferland, P. G. Martin Nov 2000

Continuum Pumping Of [Fe Ii] In The Orion Nebula, E. M. Verner, D. A. Verner, J. A. Baldwin, Gary J. Ferland, P. G. Martin

Physics and Astronomy Faculty Publications

This paper presents detailed comparisons between numerical simulations of Fe II emission spectra and recent high-resolution and signal-to-noise spectra of the Orion Nebula. We have identified 40 [Fe II] lines in the spectrum, allowing extensive comparisons between theory and observations. The identifications are based on predictions of a realistic model of the Fe II atom, which includes the lowest 371 levels (all levels up to 11.6 eV). We investigate the dependence of the spectrum on electron density and on pumping by the stellar continuum. Orion is important because it provides a relatively simple environment in which to test complex simulations. …

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Control Of Intense Laser- Atom Processes With Strong Static Fields, Dejan B. Milosevic, Anthony F. Starace Nov 2000

Control Of Intense Laser- Atom Processes With Strong Static Fields, Dejan B. Milosevic, Anthony F. Starace

Anthony F. Starace Publications

Atomic processes in the presence of intense fields continue to attract a great deal of attention [1-3]. Key goals of research in this area are to increase the intensities and frequencies of coherent light produced in these processes. In two recent works [4,5] we have demonstrated theoretically the possibility of controlling intense laser-atom interaction processes by employing strong, but experimentally feasible, static electric or magnetic fields. Thus, in Ref. [4] we demonstrated how a strong static electric field may induce a high-energy plateau for scattered x-ray photons in laser-assisted, x-ray-atom scattering in which the incident x-rays were assumed to have …

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Angular Momentum Partitioning And Hexacontatetrapole Moments In Impulsively Excited Argon Ions, H. M. Al-Khateeb, B. G. Birdsey, Timothy J. Gay Nov 2000

Angular Momentum Partitioning And Hexacontatetrapole Moments In Impulsively Excited Argon Ions, H. M. Al-Khateeb, B. G. Birdsey, Timothy J. Gay

Timothy J. Gay Publications

We have studied polarized electron collisions with Ar in which the target is simultaneously ionized and excited to form Ar+(3p4(1D)4p) states. We measured the integrated Stokes parameters of the subsequent fluorescence emitted by the 2F7/2, 2F5/2, 2D5/2, and 2P3/2 states along the direction of electron polarization. The Rubin-Bederson hypothesis is shown to hold for the L and S multipoles of these states. The electric quadrupole and hexadecapole of the 1D core are derived. By recoupling these moments with …

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Universal Quantum Limits On Single-Channel Information, Entropy, And Heat Flow, Miles Blencowe, Vincenzo Vitelli Nov 2000

Universal Quantum Limits On Single-Channel Information, Entropy, And Heat Flow, Miles Blencowe, Vincenzo Vitelli

Dartmouth Scholarship

We show that the recently discovered universal upper bound on the thermal conductance of a single channel comprising particles obeying arbitrary fractional statistics is in fact a consequence of a more general universal upper bound, involving the averaged entropy and energy currents of a single channel connecting heat reservoirs with arbitrary temperatures and chemical potentials. The latter upper bound in turn leads, via Holevo's theorem, to a universal (i.e., statistics independent) upper bound on the optimum capacity for classical information transmission down a single, wideband quantum channel.

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Comparative Studies Of Dissociative Electron Attachment To Methyl Halides, R. S. Wilde, Gordon A. Gallup, Ilya I. Fabrikant Nov 2000

Comparative Studies Of Dissociative Electron Attachment To Methyl Halides, R. S. Wilde, Gordon A. Gallup, Ilya I. Fabrikant

Gordon Gallup Publications

The dissociative electron attachment cross sections for the methyl halides vary in an enormous range from the virtually unmeasurable 10−23 cm2 for CH3Cl at room temperature to 10−14 cm2 for CH3I. In this paper we supplement our previous studies by calculations of dissociative electron attachment to CH3Br and compare results for all methyl halides studied so far. The rate as a function of temperature for CH3Cl and CH3Br exhibits an exponential dependence on 1/T (Arrhenius law) with the activation energy lower for CH3Br. …

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Two-Dimensional Pendulum Experiments Using A Spark Generator, Rand S. Worland, Matthew J. Moelter Nov 2000

Two-Dimensional Pendulum Experiments Using A Spark Generator, Rand S. Worland, Matthew J. Moelter

Physics

Student understanding of the superposition of perpendicular harmonic oscillators can be enhanced using a spark generator to record position-versus-time data for smallamplitude pendulum motion in two dimensions. Our students have used this arrangement to analyze the motion of a spherical pendulum and a “Y-suspended” (Blackburn) pendulum that has two effective lengths.

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Report Of The Qcd Tools Working Group, R. K. Ellis, R. Field, S. Mrenna, Gregory R. Snow, C. Balazs, E. Boos, J. Campbell, R. Demina, J. Huston, C-Y. P. Ngan, A. Petrelli, I. Puljak, T. Sjostrand, J. Smith, D. Stuart, K. Sumorok Nov 2000

Report Of The Qcd Tools Working Group, R. K. Ellis, R. Field, S. Mrenna, Gregory R. Snow, C. Balazs, E. Boos, J. Campbell, R. Demina, J. Huston, C-Y. P. Ngan, A. Petrelli, I. Puljak, T. Sjostrand, J. Smith, D. Stuart, K. Sumorok

Gregory Snow Publications

We report on the activities of the “QCD Tools for heavy flavors and new physics searches” working group of the Run II Workshop on QCD and Weak Bosons. The contributions cover the topics of improved parton showering and comparisons of Monte Carlo programs and resummation calculations, recent developments in Pythia, the methodology of measuring backgrounds to new physics searches, variable flavor number schemes for heavy quark electro-production, the underlying event in hard scattering processes, and the Monte Carlo MCFM for NLO processes.

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Tabletop Accelerators Are Brighter And Faster, Phil Schewe, Ben Stein, Donald P. Umstadter Nov 2000

Tabletop Accelerators Are Brighter And Faster, Phil Schewe, Ben Stein, Donald P. Umstadter

Donald Umstadter Publications

At last week's APS plasma physics meeting, Donald Umstadter of the University of Michigan's Center for Ultrafast Optical Science (734-764-2284, dpu@umich.edu) reported on advances at his lab and elsewhere in tabletop laser accelerators, devices that use light to accelerate beams of electrons and protons to energies of a million volts in distances of only microns. This acceleration rate or "gradient" is up to a thousand times larger than in conventional accelerators because the tabletop laser light can now exert pressures of gigabars, the highest ever achieved, and approaching the pressure of light near the Sun. Not only that, but Umstadter's …

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Binary Condensation In A Supersonic Nozzle, Barbara Ellen Wyslouzil, Christopher H. Heath, Janice L. Cheung, Gerald Wilemski Nov 2000

Binary Condensation In A Supersonic Nozzle, Barbara Ellen Wyslouzil, Christopher H. Heath, Janice L. Cheung, Gerald Wilemski

Physics Faculty Research & Creative Works

We present data from the first systematic studies of binary condensation in supersonic nozzles. The apparatus used to conduct the experiments is described in detail, and the important issues of stability and reproducibility of the experiments are discussed. Experiments were conducted with water, ethanol, propanol, and binary mixtures of these compounds. Onset was determined in the temperature range of 190-215 K, and for each mixture composition the pressures of the condensible species at an onset temperature of 207 K were determined. For the ideal ethanol-propanol mixtures, the onset pressures at constant temperature vary almost linearly between those of the pure …

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Combined Effects Of Screening And Band Gap Renormalization On The Energy Of Optical Transitions In Zno And Gan, D. C. Reynolds, David C. Look, B. Jogai Nov 2000

Combined Effects Of Screening And Band Gap Renormalization On The Energy Of Optical Transitions In Zno And Gan, D. C. Reynolds, David C. Look, B. Jogai

Physics Faculty Publications

The energy positions of the optical transitions in both GaN and ZnO were investigated when the samples were excited simultaneously with a HeCd laser and an Ar+ ion laser. The increased number of free electrons excited by the Ar+ ion laser will effectively screen both the free exciton and bound exciton transitions, resulting in a blueshift. The increased number of free electrons also produces many-body effects, which lead to a reduction of the band gap energy and thus a redshift. The resultant of screening and renormalization results in a redshift of the optical transitions in ZnO but a …

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