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Interpretation of f({epsilon}) measurements by T. Kimura, K. Akatsuka and K. Ohe

Description: This note describes my analysis of the measurement of the electron energy distribution function in a DC glow discharge reported by T. Kimura, K. Akatsuka, and K. Ohe, in `Experimental and theoretical investigations of DC glow discharges in argon-nitrogen mixtures,`J. Phys. D: Appl. Phys. 27 (1994) 1664-1671. T. Kimura of the Department of Systems Engineering at the Nagoya Institute of Technology sent me this paper in 1994, as well as `Electron Energy Distribution Function in Neon-Nitrogen Mixtu… more
Date: November 26, 1996
Creator: Garcia, M.
Partner: UNT Libraries Government Documents Department
open access

Differential spectral synthesis with a library of elliptical galaxies

Description: Spectrophotometry of elliptical galaxies spanning a large rang in luminosity is analyzed for cosmic variations in color and line strength. The results are used to construct a base sequence spectral energy distribution as a function line strength, color, and velocity dispersion, representing old, red, uniform elliptical galaxy stellar populations. The sequence can be used as the starting point for investigating and modeling the stellar populations of other systems such as dwarf ellipticals, merg… more
Date: December 7, 1995
Creator: Gregg, M.
Partner: UNT Libraries Government Documents Department
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Radio-loud high-redshift protogalaxy canidates in Bootes

Description: We used the Near Infrared Camera (NIRC) on Keck I to obtain K{sub s}-band images of four candidate high-redshift radio galaxies selected using optical and radio data in the NOAO Deep Wide-Field Survey in Bootes. Our targets have 1.4 GHz radio flux densities greater than 1 mJy, but are undetected in the optical. Spectral energy distribution fitting suggests that three of these objects are at z > 3, with radio luminosities near the FR-I/FR-II break. The other has photometric redshift z{sub pho… more
Date: July 20, 2007
Creator: Croft, S.; van Breugel, W.; Brown, M. J.; de Vries, W.; Dey, A.; Eisenhardt, P. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of a Multi-Layer Guided Wave Inspection Technique

Description: This study investigates the inspection of a particular layer of a multi-layer structure using ultrasonic guided waves. Techniques based on Lamb waves have been developed for the inspection of plate structures and are well understood. Guided waves also exist in multi-layered plates as well. Energy distributions vary across the thickness of a multi-layer structure depending on the mode and frequency. Hence, a potential way to inspect the bottom layer of a structure is to find modes with sufficien… more
Date: March 12, 2001
Creator: Quarry, M; Chinn, D & Hay, T
Partner: UNT Libraries Government Documents Department
open access

BEVATRON RESEARCH MEETING V - HIGH ENERGY NUCLEAR INTERACTION

Description: There are two different types of investigation of interest in high energy nuclear phenomena. One can observe gross effects such as the production of large numbers of heavy particles of different types, or one can study the elementary particles themselves which result from these collisions, for example, the kappa mesons, to determine modes of decay and the energy spectra of the resulting particles. This discussion will deal with the gross aspects of high energy interactions and will review the w… more
Date: November 3, 1953
Creator: Lepore, Joseph
Partner: UNT Libraries Government Documents Department
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Two-electron time-delay interference in atomic double ionization by attosecond pulses

Description: A two-color two-photon atomic double ionization experiment using subfemtosecond UV pulses can be designed such that the sequential two-color process dominates and one electron is ejected by each pulse. Nonetheless, ab initio calculations show that, for sufficiently short pulses, a prominent interference pattern in the joint energy distribution of the sequentially ejected electrons can be observed that is due to their indistinguishability and the exchange symmetry of the wave function.
Date: October 4, 2009
Creator: Rescigno, Thomas N
Partner: UNT Libraries Government Documents Department
open access

Supersymmetry, Naturalness, and Signatures at the LHC

Description: Weak scale supersymmetry is often said to be fine-tuned, especially if the matter content is minimal. This is not true if there is a large A term for the top squarks. We present a systematic study on fine-tuning in minimal supersymmetric theories and identify low energy spectra that do not lead to severe fine-tuning. Characteristic features of these spectra are: a large A term for the top squarks, small top squark masses, moderately large tan {beta}, and a small {mu} parameter. There are classe… more
Date: February 10, 2006
Creator: Kitano, Ryuichiro & Nomura, Yasunori
Partner: UNT Libraries Government Documents Department
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Extra dimensions vs. supersymmetric interpretation of missing energy events at a linear collider

Description: The photon plus missing energy signature is a primary handle on two important classes of theories. Theories with large extra dimensions predict the production of photons in association with Kaluza-Klein excitations of the graviton. In supersymmetric theories with superlight gravitinos, photons can be produced in association with gravitino pairs. The signatures for these two theories are compared, and it is found that they can be distinguished by studying the photon energy distributions and scal… more
Date: October 25, 2001
Creator: Gopalakrishna, Shrihari; Perelstein, Maxim & Wells, James D.
Partner: UNT Libraries Government Documents Department
open access

Nitrogen Atom Energy Distributions in a Hollow-cathode Planar Sputtering Magnetron

Description: Energy distributions of N atoms in a hollow-cathode planar sputtering magnetron were obtained by use of optical emission spectroscopy. A characteristic line, N I 8216.3 Å, well-separated from molecular nitrogen emission bands, was identified. Jansson's nonlinear spectral deconvolution method, refined by minimization of {chi}<sub>w</sub> &sup2; , was used to obtain the optimal deconvolved spectra. These showed nitrogen atom energies from 1 eV to beyond 500 eV. Based on comparisons with VFTRIM re… more
Date: June 1, 1999
Creator: Ruzic, D. N.; Goeckner, M. J.; Cohen, Samuel A. & Wang, Zhehui
Partner: UNT Libraries Government Documents Department
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Delayed Gamma Rays From Fission. Technical Report, August 1, 1965-July 31, 1966.

Description: Measurements of the energy spectrum of delayed gamma rays from the neutron fission of Pu$sup 239$ and U$sup 235$ were performed with a NaI detector at a number of time intervals between 2 μsec and 80 μsec. The data showed three new prominent gamma rays with energies of 205, 390, and 1330 keV; two unresolved gamma rays having energies of approximately 110 keV; and the six gamma rays with energies of 260, 460, 720, 850, 910, and 1250 keV which were observed in previous studies for t > 50 μsec aft… more
Date: January 1, 1966
Creator: Walton, R.B. & Sund, R.E.
Partner: UNT Libraries Government Documents Department
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Alignment of the MINOS FD

Description: The results and procedure of the alignment of the MINOS Far Detector are presented. The far detector has independent alignments of SM1 and SM2. The misalignments have an estimated uncertainty of {approx}850 {micro}m for SM1 and {approx}750 {micro}m for SM2. The alignment has as inputs the average rotations of U and V as determined by optical survey and strip positions within modules measured from the module mapper. The output of this is a module-module correction for transverse mis-alignments. … more
Date: November 1, 2004
Creator: Becker, B. & Boehnlein, D.
Partner: UNT Libraries Government Documents Department
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Estimate of the energy spread in a booster cycle via the bunch length measurement

Description: It is important for us to obtain the information of energy spread vs. time in a Booster cycle via the same beam event, for the purpose of minimizing the error caused by the cycle-to-cycle fluctuation. The bunch length (BL) can be extracted from the resistive wall signal (RWS) at different times of a Booster cycle, and from which the energy spread can be estimated.
Date: November 1, 2004
Creator: Yang, Xi
Partner: UNT Libraries Government Documents Department
open access

POPULATION KINETICS MODELING FOR NON-LTE AND NON-MAXWELLIAN PLASMAS GENERATED IN FINITE TEMPERATURE DENSE MATTER EXPERIMENTS ARISING FROM SHORT PULSE X-RAY SOURCE

Description: The short pulse x-ray sources will provide a major advance in dense matter studies important to understand implosion physics for ICF as a generator of warm dense matter or a probe of finite temperature dense matter. The interaction of such a high-energy photon pulse with the initially solid matter creates highly transient states of plasmas initially whose relaxation processes are of interest to the equation of states or spectral properties of these matter. For these plasmas, assumptions such as… more
Date: December 23, 2003
Creator: Chung, H; Lee, R W & Morgan, W L
Partner: UNT Libraries Government Documents Department
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CRADA Final Report CRADA No. LB05-001820&quot;Ion Beam Drift Compression Technology for NDCX&quot;

Description: Summary of the specific research and project accomplishments: Through this collaboration, LBNL and FPSI determined the specific energy manipulations that apply to the Neutralized Drift Compression Experiment (NDCX) ion beam and developed the preliminary design of a Fast Induction Energy Corrector (FIEC). This effort was successfully completed, firmly establishing the technical feasibility of the proposed approach for regulating the longitudinal energy distribution of the NDCX ion beam. This is … more
Date: October 5, 2009
Creator: First point Scientific, Inc.; Laboratory, E.O. Lawrence Berkeley National & Waldron, William L.
Partner: UNT Libraries Government Documents Department
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Intensity distributions of gamma-ray bursts

Description: Observations of individual bursts chosen by the vagaries of telescope availability demonstrated that bursts are not standard candles and that their apparent energy can be as great as 10{sup 54} erg. However, determining the distribution of their apparent energy (and of other burst properties) requires the statistical analysis of a well-defined burst sample; the sample definition includes the threshold for including a burst in the sample. Thus optical groups need to the criteria behind the decis… more
Date: January 1, 2001
Creator: Band, D. L. (David L.)
Partner: UNT Libraries Government Documents Department
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Two-photon double ionization of the helium atom by ultrashort pulses

Description: Two-photon double ionization of the helium atom was the subject of early experiments at FLASH and will be the subject of future benchmark measurements of the associated electron angular and energy distributions. As the photon energy of a single femtosecond pulse is raised from the threshold for two-photon double ionization at 39.5 eV to beyond the sequential ionization threshold at 54.4 eV, the electron ejection dynamics change from the highly correlated motion associated with nonsequential abs… more
Date: May 14, 2010
Creator: Palacios, Alicia; Horner, Daniel A.; Rescigno, Thomas N. & McCurdy, C. William
Partner: UNT Libraries Government Documents Department
open access

Absolute Measurement of Electron Cloud Density in a Positively-Charged Particle Beam

Description: Clouds of stray electrons are ubiquitous in particle accelerators and frequently limit the performance of storage rings. Earlier measurements of electron energy distribution and flux to the walls provided only a relative electron cloud density. We have measured electron accumulation using ions expelled by the beam. The ion energy distribution maps the depressed beam potential and gives the dynamic cloud density. Clearing electrode current reveals the static background cloud density, allowing th… more
Date: April 27, 2006
Creator: Kireeff Covo, Michel; Molvik, Arthur W.; Friedman, Alex; Vay, Jean-Luc; Seidl, Peter A.; Logan, Grant et al.
Partner: UNT Libraries Government Documents Department
open access

Characterization of SF6/Argon Plasmas for Microelectronics Applications

Description: This report documents measurements in inductively driven plasmas containing SF{sub 6}/Argon gas mixtures. The data in this report is presented in a series of appendices with a minimum of interpretation. During the course of this work we investigated: the electron and negative ion density using microwave interferometry and laser photodetachment; the optical emission; plasma species using mass spectrometry, and the ion energy distributions at the surface of the rf biased electrode in several conf… more
Date: March 1, 2002
Creator: HEBNER, GREGORY A.; ABRAHAM, ION C. & WOODWORTH, JOSEPH R.
Partner: UNT Libraries Government Documents Department
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