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Heavy Residue Spectra in the Interaction of 85 A MeV 12C with197Au

Description: We have measured the heavy residue differential range distributions in the interaction of 85 MeV/nucleon {sup 12}C with {sup 197}Au. The range distributions were converted to energy spectra using known range-energy relationships. The mean residue energies range from 15 keV/nucleon (A = 189) to 314 keV/nucleon (A = 131). Longitudinal momenta of the heavy residues have been deduced (<p{sub {parallel}} > /p{sub cn} = 0.27). The mean spectral energies and the shapes of the residue spectra are… more
Date: December 1, 1988
Creator: Aleklett, K.; Johansson, M.; Lihver, L.; Loveland, W.; Groening, H.; McGaughey, P. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laboratory laser acceleration and high energy astrophysics: {gamma}-ray bursts and cosmic rays

Description: Recent experimental progress in laser acceleration of charged particles (electrons) and its associated processes has shown that intense electromagnetic pulses can promptly accelerate charged particles to high energies and that their energy spectrum is quite hard. On the other hand some of the high energy astrophysical phenomena such as extremely high energy cosmic rays and energetic components of {gamma}-ray bursts cry for new physical mechanisms for promptly accelerating particles to high ener… more
Date: August 20, 1998
Creator: Tajima, T. & Takahashi, Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Non-thermal photodesorption of N{sub 2} from Ag(111)

Description: The authors have measured translational and rotational energy distributions of N{sub 2} molecules following desorption from a Ag(111) surface by infrared (1,064 nm) radiation. The observed desorption yields were large even at laser fluences far below that required for laser induced thermal desorption. State resolved laser techniques using coherent VUV radiation showed that the rotational and translational energy distributions of the desorbing N{sub 2} molecules are not consistent with the predi… more
Date: February 1998
Creator: Rao, R. M.; Beuhler, R. J. & White, M. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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First principles calculations for litiated manganese oxides

Description: First principles calculations using the local-spin-density-functional theory are presented of densities of electronic states for MnO, LiMnO{sub 2} in the monoclinic and orthorhombic structures, cubic LiMn{sub 2}O{sub 4} spinel, and {lambda}-MnO{sub 2} (delithiated spinel), all in antiferromagnetic spin configurations. The changes in energy spectra as the Mn oxidation state varies between 2+ and 4+ are illustrated. Preliminary calculations for Co-doped LiMnO{sub 2} are presented, and the destabi… more
Date: December 22, 1998
Creator: Benedek, R.; Prasad, R.; Thackeray, M. M.; Wills, J. M. & Yang, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Particle Simulations of a Linear Dielectric Wall Proton Accelerator

Description: The dielectric wall accelerator (DWA) is a compact induction accelerator structure that incorporates the accelerating mechanism, pulse forming structure, and switch structure into an integrated module. The DWA consists of stacked stripline Blumlein assemblies, which can provide accelerating gradients in excess of 100 MeV/meter. Blumleins are switched sequentially according to a prescribed acceleration schedule to maintain synchronism with the proton bunch as it accelerates. A finite difference … more
Date: June 12, 2007
Creator: Poole, B R; Blackfield, D T & Nelson, S D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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THREE AND FOUR CENTER ELIMINATION OF HC1 IN THE MULTIPHOTON DISSOCIATION OF HALOGENATED HYDROCARBONS

Description: Three and four center unimolecular elimination reactions of HCl have been investigated for CHF{sub 2}Cl, CHFCL{sub 2}, CH{sub 3}CCl{sub 3}, CH{sub 3}CF{sub 2}Cl and in a molecular beam experiment using infrared multiphoton absorption to energize the molecule. The translational energy distributions obtained in this work show that the average translational energy released to the fragments is around 8-12 kcal/mole, except for the three center elimination reaction from CHClCF{sub 2}, which gives a … more
Date: April 1, 1978
Creator: Sudbo, Aa. S.; Schulz, P.A.; Shen, Y.R. & Lee, Y.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multiwavelength Observations of Mrk 501 in 2008

Description: The well-studied VHE (E > 100 GeV) blazar Mrk 501 was observed between March and May 2008 as part of an extensive multiwavelength observation campaign including radio, optical, X-ray and VHE gamma-ray instruments. Mrk 501 was in a low state of activity during the campaign, with a low VHE flux of about 20% the Crab Nebula flux. Nevertheless, significant flux variations could be observed in X-rays as well as {gamma}-rays. Overall Mrk 501 showed increased variability when going from radio to {g… more
Date: August 25, 2010
Creator: Kranich, D.; /Zurich, ETH; Paneque, D.; /SLAC; Cesarini, A.; /Natl. U. of Ireland, Galway et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Polarimetry on RGB BL lacs

Description: We present results on polarimetry on RGB BL Lacs. This sample has its roots in ROSAT and Green Bank catalogues. The broad band spectral energy distribution of RGB BL Lacs differs from the ''traditional'' BL Lacs, filling the gap between two extremes, HBLs and LBLs. We found that the polarization properties of the sample are also intermediate to HBLs and LBLs. The highest measured polarization was {minus}19% and {minus}60% of the objects had high polarization. Our results suggests that there is … more
Date: June 1, 1998
Creator: Heinamaki, P.; Katajainen, S.; Laurent-Muehleisen, S. A.; Nilsson, K.; Pursimo, T.; Schmidt, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetorheological Finishing for Imprinting Continuous Phase Plate Structure onto Optical Surfaces

Description: Magnetorheological finishing (MRF) techniques have been developed to manufacture continuous phase plates (CPP's) and custom phase corrective structures on polished fused silica surfaces. These phase structures are important for laser applications requiring precise manipulation and control of beam-shape, energy distribution, and wavefront profile. The MRF's unique deterministic-sub-aperture polishing characteristics make it possible to imprint complex topographical information onto optical surfa… more
Date: January 5, 2004
Creator: Menapace, J A; Dixit, S N; Genin, F Y & Brocious, W F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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AEGIS: The Diversity of Bright Near-IR Selected Distant RedGalaxies

Description: We use deep and wide near infrared (NIR) imaging from the Palomar telescope combined with DEEP2 spectroscopy and Hubble Space Telescope (HST) and Chandra Space Telescope imaging to investigate the nature of galaxies that are red in NIR colors. We locate these 'distant red galaxies' (DRGs) through the color cut (J - K){sub vega} > 2.3 over 0.7 deg{sup 2}, where we find 1010 DRG candidates down to K{sub s} = 20.5. We combine 95 high quality spectroscopic redshifts with photometric redshifts fr… more
Date: October 13, 2006
Creator: Conselice, C. J.; Newman, J. A.; Georgakakis, A.; Almaini, O.; Coil, A. L.; Cooper, M. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photodissociation of NO{sub 2} near 225 nm by Velocity Map Imaging

Description: In this paper we present a study of the photodissociation dynamics for NO{sub 2} in the region of 221-226 nm using velocity map imaging (VELMI) in conjunction with resonance enhanced multiphoton ionization (REMPI). We chose this region because it allowed us to use a single laser to photodissociate and probe the NO and O({sup 3}P) products using REMPI. Probing the angular and energy distributions of both fragments under state resolved conditions allows for detailed investigations of the product … more
Date: October 1, 1998
Creator: Ahmed, Musahid; Peterka, D. S. & Suits, A. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of the longitudinal wakefield and the bunch shape in the SLAC linac

Description: The authors report on measurements of the bunch energy spectrum at the end of the SLAC linac. Using the spectra obtained for two different linac rf phases they obtain both the bunch induced voltage and the longitudinal distribution of the bunch. The measurement results are compared with theoretical predictions. In particular, the induced voltage is in good agreement with that obtained using the calculated wake function for the SLAC linac. This measurement technique may be useful for monitoring … more
Date: May 1, 1997
Creator: Bane, K. L. F.; Decker, F. J.; Seeman, J. T. & Zimmermann, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of selected modern filter media for use in radon/thoron progeny measurements

Description: We tested a number of air sampling filters to determine their suitability for use in radon/thoron progeny measurements. The main test consisted of sampling a radon progeny atmosphere, then measuring the energy spectrum of the alpha particles emerging from the face of the filter. It was found that Millipore AA, long a favorite for this application, is still a good choice. However, this filter is prone to developing electrostatic charge, which can cause the additional collection of {sup 218}Po du… more
Date: April 1, 1996
Creator: Knutson, E.O. & Seo, Kyung-Won
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ANALYSIS OF THE INTERACTION OF 300-Mev NEUTRONS WITH XENON

Description: An investigation of the interactions between 300-Mev neutrons and xenon was made by means of a cloud chamber in a pulsed magnetic field of 21,700 gauss placed in the neutron beam of the 184-inch Berkeley cyclotron. Eighty-seven negative pion events and 257 other stars were analyzed. In addition an experimental check was made on the energy of the incoming neutrons. Classification, identification, and angular and energy distributions of prongs associated with all events are presented. Interpretat… more
Date: October 17, 1956
Creator: Morris, Richard Herbert.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Applications of Laser and Synchrotron Based ARPES to Photocathode Research

Description: Laser angle resolved photoelectron spectroscopy (ARPES) provides unique information about angle and energy distribution of photoelectrons. Laser ARPES gives unique insight into how NEA materials work. ARPES combined with some ancillary measurements gives a very complete picture of system electronic physics. For H:C[100] there is now a clear program for engineering as well as development analogous systems. ARPES well suited for identifying 'ideal' photocathodes with intrinsically low emittance a… more
Date: October 12, 2010
Creator: Rameau, J.; Smedley. J.; Muller, E.; Kidd, T.; Johnson, P.; Allen, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Extended X-ray Nebula of PSR J1420-6048

Description: The vicinity of the unidentified EGRET source 3EG J1420-6038 has undergone extensive study in the search for counterparts, revealing the energetic young pulsar PSR J1420-6048 and its surrounding wind nebula as a likely candidate for at least part of the emission from this bright and extended gamma-ray source. We report on new Suzaku observations of PSR J1420-6048, along with analysis of archival XMM Newton data. The low background of Suzaku permits mapping of the extended X-ray nebula, indicati… more
Date: August 19, 2011
Creator: Van Etten, Adam; Romani, Roger W. & /Stanford U., Phys. Dept.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simultaneous Observations of PKS 2155--304 with H.E.S.S., Fermi, RXTE and ATOM: Spectral Energy Distributions and Variability in a Low State

Description: We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155-304. The gamma-ray bands were observed for 11 days, between 2008 August 25 and 2008 September 6 (MJD 54704-54715), jointly with the Fermi Gamma-ray Space Telescope and the HESS atmospheric Cherenkov array, providing the first simultaneous MeV-TeV spectral energy distribution (SED) with the new generation of {gamma}-ray telescopes. The ATOM telescope and t… more
Date: May 7, 2009
Creator: Aharonian, F.; Akhperjanian, A. G.; Anton, G.; Barres de Almeida, U.; Bazer-Bachi, A. R.; Becherini, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observations of cold magnetospheric ions at geosynchronous orbit during times of high activity

Description: Flowing, cold magnetospheric ions have been observed in conjunction with geosynchronous orbit magnetopause crossings since the earliest ATS and OGO missions. The authors have reported on the occurrence and convection of low-energy (10-100 eV) ions seen by multiple satellites in association with geosynchronous orbit magnetopause and low-latitude boundary layer (LLBL) encounters. More generally, Los Alamos 3-D plasma instruments observe these ions following storm sudden commencements (SSCs), when… more
Date: October 1, 1994
Creator: Elphic, R. C.; Weiss, L. A.; Thomsen, M. F.; McComas, D. J. & Bame, S. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ANALYSIS OF SPACE CHARGE DRIVEN MODULATION IN ELECTRON BUNCH ENERGY SPECTRA.

Description: As was discussed earlier [1,2] longitudinal space charge force in initially nonuniform bunch transforms density fluctuations into energy modulation along the bunch. For characterization of the resulted energy modulation one can chirp the bunch using accelerator section, located upstream of beam spectrometer, and record energy spectrum of such chirped bunch. Measured spectrum shows structure with parameters, depending on the bunch properties. In this paper we present analysis of the structure in… more
Date: August 22, 2003
Creator: SHAFTAN,T. YU,L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A scaling theory for the assignment of spectra in the irregular region. Continuation progress report

Description: The ultimate object of our program is to learn how to extract information about molecular rovibrational motions from experimental spectra or calculated energy levels. This goal of spectroscopy and theoretical chemistry has historically only been possible in the regular spectral region. Our project is one of several which are aimed at spectral interpretation in the chaotic or mixed chaotic plus regular regions. Our particular tools involve a scaling theory developed under our previous DOE suppor… more
Date: June 1, 1998
Creator: Taylor, H.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron emission following the interaction of slow highly charged ions with solids

Description: The interaction of highly-charged ions with surfaces involves many excitation processes of the surface atoms and the bulk material. One such process, the emission of electrons from surfaces due to the potential energy of the incident ions has been studied. The experimental results presented here confirm that the majority of electrons emitted as a result of highly-charged ions interacting with a solid surface have energies of about 20 eV. Auger processes contribute a smaller fraction of the tota… more
Date: January 1, 1998
Creator: McDonald, J.W., LLNL
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Determination of the Atmospheric Neutrino Flux and Searches for New Physics with AMANDA-II

Description: The AMANDA-II detector, operating since 2000 in the deep ice at the geographic South Pole, has accumulated a large sample of atmospheric muon neutrinos in the 100 GeV to 10 TeV energy range. The zenith angle and energy distribution of these events can be used to search for various phenomenological signatures of quantum gravity in the neutrino sector, such as violation of Lorentz invariance (VLI) or quantum decoherence (QD). Analyzing a set of 5511 candidate neutrino events collected during 1387… more
Date: June 2, 2009
Creator: Collaboration, IceCube; Klein, Spencer & Collaboration, IceCube
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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