Degree Department

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The Boerne Star (Boerne, Tex.), Vol. 104, No. 22, Ed. 1 Tuesday, March 16, 2010 (open access)

The Boerne Star (Boerne, Tex.), Vol. 104, No. 22, Ed. 1 Tuesday, March 16, 2010

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Cartwright, Brian & Velvin, Candace E.
Object Type: Newspaper
System: The Portal to Texas History
Perry Daily Journal (Perry, Okla.), Vol. 118, No. 51, Ed. 1 Tuesday, March 16, 2010 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 118, No. 51, Ed. 1 Tuesday, March 16, 2010

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 112, No. 71, Ed. 1 Tuesday, March 16, 2010 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 71, Ed. 1 Tuesday, March 16, 2010

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Oral History Interview with Merton Bobo, March 16, 2010 transcript

Oral History Interview with Merton Bobo, March 16, 2010

The National Museum of the Pacific War presents an oral interview with Merton Bobo. Bobo was born in Greenfield, Maine 10 February 1926. Graduating from high school in 1943 he enlisted in the Navy. Following a six week boot camp in Sampson, New York he was sent to Jacksonville, Florida to attend radio school. Once he graduated, he was sent to Yellow Water, Florida for gunnery training. Upon completing the gunnery training, he went to Fort Lauderdale, where he began operational training in a TBM with a pilot and gunner. The crew stayed together during their combat tour. Upon completion of the advanced training the crew went to San Diego where they joined VC-90. Going to Hawaii, they were trained in the use of rockets and torpedoes. The crew was assigned to the USS Steamer Bay (CVE-87) and began making patrols and practice landings. They joined a task unit and sailed to the Mindoro Straits where they were under attack by Japanese planes for five days. During this time Bobo witnessed a kamikaze crashing into the USS Ommaney Bay (CVE-79). He participated in combat missions at Lingayen Gulf, Iwo Jima and Okinawa. He recalls the night their ship was in …
Date: March 16, 2010
Creator: Bobo, Merton
Object Type: Sound
System: The Portal to Texas History
Oral History Interview with Merton Bobo, March 16, 2010 (open access)

Oral History Interview with Merton Bobo, March 16, 2010

The National Museum of the Pacific War presents an oral interview with Merton Bobo. Bobo was born in Greenfield, Maine 10 February 1926. Graduating from high school in 1943 he enlisted in the Navy. Following a six week boot camp in Sampson, New York he was sent to Jacksonville, Florida to attend radio school. Once he graduated, he was sent to Yellow Water, Florida for gunnery training. Upon completing the gunnery training, he went to Fort Lauderdale, where he began operational training in a TBM with a pilot and gunner. The crew stayed together during their combat tour. Upon completion of the advanced training the crew went to San Diego where they joined VC-90. Going to Hawaii, they were trained in the use of rockets and torpedoes. The crew was assigned to the USS Steamer Bay (CVE-87) and began making patrols and practice landings. They joined a task unit and sailed to the Mindoro Straits where they were under attack by Japanese planes for five days. During this time Bobo witnessed a kamikaze crashing into the USS Ommaney Bay (CVE-79). He participated in combat missions at Lingayen Gulf, Iwo Jima and Okinawa. He recalls the night their ship was in …
Date: March 16, 2010
Creator: Bobo, Merton
Object Type: Text
System: The Portal to Texas History
The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, March 16, 2010 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, March 16, 2010

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Wray, Kelly
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Swisher County News (Tulia, Tex.), Vol. 2, No. 9, Ed. 1 Tuesday, March 16, 2010 (open access)

The Swisher County News (Tulia, Tex.), Vol. 2, No. 9, Ed. 1 Tuesday, March 16, 2010

Weekly newspaper from Tulia, Texas that includes local, state, and national news along with extensive advertising.
Date: March 16, 2010
Creator: Hooten, Patsy
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 90, No. 53, Ed. 1 Tuesday, March 16, 2010 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 90, No. 53, Ed. 1 Tuesday, March 16, 2010

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Halter, Janie
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 128, Ed. 1 Tuesday, March 16, 2010 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 128, Ed. 1 Tuesday, March 16, 2010

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Shance, Brenda
Object Type: Newspaper
System: The Gateway to Oklahoma History
Rains County Leader (Emory, Tex.), Vol. 123, No. 39, Ed. 1 Tuesday, March 16, 2010 (open access)

Rains County Leader (Emory, Tex.), Vol. 123, No. 39, Ed. 1 Tuesday, March 16, 2010

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: March 16, 2010
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
[Clipping: Local Eleanor Brown awarded DAR "Women in American History Award"] (open access)

[Clipping: Local Eleanor Brown awarded DAR "Women in American History Award"]

Newspaper clipping of an article about Eleanor "Mickey" Brown receiving the "Women in American History Award" from the Daughters of the American Revolution (DAR). The article includes a photo of Brown holding the award with DAR Regent Sandra Skach. There is an article about passing on heritage to the next generation on the back of the clipping.
Date: March 16, 2010
Creator: unknown
Object Type: Clipping
System: The Portal to Texas History
[Letter from Janey Lack to Eleanor Brown, March 16, 2010] (open access)

[Letter from Janey Lack to Eleanor Brown, March 16, 2010]

Letter from Janey Lack to Mickey McLernan saying that she enjoyed the article and hopes she enjoyed her trip to D. C..
Date: March 16, 2010
Creator: Lack, Janey
Object Type: Letter
System: The Portal to Texas History
Untangling the Chemical Evolution of Titan's Atmosphere and Surface -- From Homogeneous to Heterogeneous Chemistry (open access)

Untangling the Chemical Evolution of Titan's Atmosphere and Surface -- From Homogeneous to Heterogeneous Chemistry

The arrival of the Cassini-Huygens probe at Saturn's moon Titan - the only Solar System body besides Earth and Venus with a solid surface and a thick atmosphere with a pressure of 1.4 atm at surface level - in 2004 opened up a new chapter in the history of Solar System exploration. The mission revealed Titan as a world with striking Earth-like landscapes involving hydrocarbon lakes and seas as well as sand dunes and lava-like features interspersed with craters and icy mountains of hitherto unknown chemical composition. The discovery of a dynamic atmosphere and active weather system illustrates further the similarities between Titan and Earth. The aerosol-based haze layers, which give Titan its orange-brownish color, are not only Titan's most prominent optically visible features, but also play a crucial role in determining Titan's thermal structure and chemistry. These smog-like haze layers are thought to be very similar to those that were present in Earth's atmosphere before life developed more than 3.8 billion years ago, absorbing the destructive ultraviolet radiation from the Sun, thus acting as 'prebiotic ozone' to preserve astrobiologically important molecules on Titan. Compared to Earth, Titan's low surface temperature of 94 K and the absence of liquid water …
Date: March 16, 2010
Creator: Kaiser, Ralf I.; Maksyutenko, Pavlo; Ennis, Courtney; Zhang, Fangtong; Gu, Xibin; Krishtal, Sergey P. et al.
Object Type: Article
System: The UNT Digital Library
New Isotope 263Hs (open access)

New Isotope 263Hs

A new isotope of Hs was produced in the reaction 208Pb(56Fe, n)263Hs at the 88-Inch Cyclotron of the Lawrence Berkeley National Laboratory. Six genetically correlated nuclear decay chains have been observed and assigned to the new isotope 263Hs. The measured cross section was 21+13-8.4 pb at 276.4 MeV lab-frame center-of-target beam energy. 263Hs decays with a half-life of 0.74 ms by alpha-decay and the measured alpha-particle energies are 10.57 +- 0.06, 10.72 +- 0.06, and 10.89 +- 0.06 MeV. The experimental cross section is compared to a theoretical prediction based on the Fusion by Diffusion model [W. J. Swiatecki et al., Phys. Rev. C 71, 014602 (2005)].
Date: March 16, 2010
Creator: Dragojevic, I.; Gregorich, K. E.; Dullmann, Ch. E.; Dvorak, J.; Ellison, P. A.; Gates, J. M. et al.
Object Type: Article
System: The UNT Digital Library
Direct detection of pyridine formation by the reaction of CH (CD) with pyrrole: a ring expansion reaction (open access)

Direct detection of pyridine formation by the reaction of CH (CD) with pyrrole: a ring expansion reaction

The reaction of the ground state methylidyne radical CH (X2Pi) with pyrrole (C4H5N) has been studied in a slow flow tube reactor using Multiplexed Photoionization Mass Spectrometry coupled to quasi-continuous tunable VUV synchrotron radiation at room temperature (295 K) and 90 oC (363 K), at 4 Torr (533 Pa). Laser photolysis of bromoform (CHBr3) at 248 nm (KrF excimer laser) is used to produce CH radicals that are free to react with pyrrole molecules in the gaseous mixture. A signal at m/z = 79 (C5H5N) is identified as the product of the reaction and resolved from 79Br atoms, and the result is consistent with CH addition to pyrrole followed by Helimination. The Photoionization Efficiency curve unambiguously identifies m/z = 79 as pyridine. With deuterated methylidyne radicals (CD), the product mass peak is shifted by +1 mass unit, consistent with the formation of C5H4DN and identified as deuterated pyridine (dpyridine). Within detection limits, there is no evidence that the addition intermediate complex undergoes hydrogen scrambling. The results are consistent with a reaction mechanism that proceeds via the direct CH (CD) cycloaddition or insertion into the five-member pyrrole ring, giving rise to ring expansion, followed by H atom elimination from the nitrogen …
Date: March 16, 2010
Creator: Soorkia, Satchin; Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Trevitt, Adam J.; Wilson, Kevin R. et al.
Object Type: Article
System: The UNT Digital Library
Precision Measurements of Tau Lepton Decays (open access)

Precision Measurements of Tau Lepton Decays

Using data collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, the branching fractions {Beta}({tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (8.83 {+-} 0.01 {+-} 0.13)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (0.273 {+-} 0.002 {+-} 0.009)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}}) = (0.1346 {+-} 0.0010 {+-} 0.0036)%, and {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}) = (1.58 {+-} 0.13 {+-} 0.12) x 10{sup -5} are measured where the uncertainties are statistical and systematic, respectively. The invariant mass distribution for the {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}, {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} decays are unfolded to correct for detector effects. A measurement of {Beta}({tau}{sup -} {yields} {phi}{pi}{sup -}{nu}{sub {tau}}) = (3.42 {+-} 0.55 {+-} 0.25) x 10{sup -5}, a measurement of {Beta}({tau}{sup -} {yields} {phi}K{sup -}{nu}{sub {tau}}) = (3.39 {+-} 0.20 {+-} 0.28) x 10{sup -5} and an upper limit on {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}[ex.{phi}]) {le} 2.5 x 10{sup -6} {at} 905 CL are determined from …
Date: March 16, 2010
Creator: Nugent, Ian M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Spin Hall effects for cold atoms in a light induced gauge potential (open access)

Spin Hall effects for cold atoms in a light induced gauge potential

We propose an experimental scheme to observe spin Hall effects with cold atoms in a light induced gauge potential. Under an appropriate configuration, the cold atoms moving in a spatially varying laser field experience an effective spin-dependent gauge potential. Through numerical simulation, we demonstrate that such a gauge field leads to observable spin Hall currents under realistic conditions. We also discuss the quantum spin Hall state in an optical lattice.
Date: March 16, 2010
Creator: Zhu, Shi-Liang; /Michigan U., MCTP /South China Normal U.; Fu, Hao; /Michigan U., MCTP; Wu, C.-J.; /Santa Barbara, KITP et al.
Object Type: Article
System: The UNT Digital Library
Band Collapse and the Quantum Hall Effect in Graphene (open access)

Band Collapse and the Quantum Hall Effect in Graphene

The recent Quantum Hall experiments in graphene have confirmed the theoretically well-understood picture of the quantum Hall (QH) conductance in fermion systems with continuum Dirac spectrum. In this paper we take into account the lattice, and perform an exact diagonalization of the Landau problem on the hexagonal lattice. At very large magnetic fields the Dirac argument fails completely and the Hall conductance, given by the number of edge states present in the gaps of the spectrum, is dominated by lattice effects. As the field is lowered, the experimentally observed situation is recovered through a phenomenon which we call band collapse. As a corollary, for low magnetic field, graphene will exhibit two qualitatively different QHE's: at low filling, the QHE will be dominated by the 'relativistic' Dirac spectrum and the Hall conductance will be odd-integer; above a certain filling, the QHE will be dominated by a non-relativistic spectrum, and the Hall conductance will span all integers, even and odd.
Date: March 16, 2010
Creator: Bernevig, B.Andrei; Hughes, Taylor L.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.; Chen, Han-Dong; /Illinois U., Urbana et al.
Object Type: Article
System: The UNT Digital Library
Fermi Liquid Instabilities in the Spin Channel (open access)

Fermi Liquid Instabilities in the Spin Channel

We study the Fermi surface instabilities of the Pomeranchuk type in the spin triplet channel with high orbital partial waves (F{sub l}{sup a} (l > 0)). The ordered phases are classified into two classes, dubbed the {alpha} and {beta}-phases by analogy to the superfluid {sup 3}He-A and B-phases. The Fermi surfaces in the {alpha}-phases exhibit spontaneous anisotropic distortions, while those in the {beta}-phases remain circular or spherical with topologically non-trivial spin configurations in momentum space. In the {alpha}-phase, the Goldstone modes in the density channel exhibit anisotropic overdamping. The Goldstone modes in the spin channel have nearly isotropic underdamped dispersion relation at small propagating wavevectors. Due to the coupling to the Goldstone modes, the spin wave spectrum develops resonance peaks in both the {alpha} and {beta}-phases, which can be detected in inelastic neutron scattering experiments. In the p-wave channel {beta}-phase, a chiral ground state inhomogeneity is spontaneously generated due to a Lifshitz-like instability in the originally nonchiral systems. Possible experiments to detect these phases are discussed.
Date: March 16, 2010
Creator: Wu, Congjun; /Santa Barbara, KITP; Sun, Kai; Fradkin, Eduardo; /Illinois U., Urbana; Zhang, Shou-Cheng et al.
Object Type: Article
System: The UNT Digital Library
Random Number Generation for Petascale Quantum Monte Carlo (open access)

Random Number Generation for Petascale Quantum Monte Carlo

The quality of random number generators can affect the results of Monte Carlo computations, especially when a large number of random numbers are consumed. Furthermore, correlations present between different random number streams in a parallel computation can further affect the results. The SPRNG software, which the author had developed earlier, has pseudo-random number generators (PRNGs) capable of producing large numbers of streams with large periods. However, they had been empirically tested on only thousand streams earlier. In the work summarized here, we tested the SPRNG generators with over a hundred thousand streams, involving over 10^14 random numbers per test, on some tests. We also tested the popular Mersenne Twister. We believe that these are the largest tests of PRNGs, both in terms of the numbers of streams tested and the number of random numbers tested. We observed defects in some of these generators, including the Mersenne Twister, while a few generators appeared to perform well. We also corrected an error in the implementation of one of the SPRNG generators.
Date: March 16, 2010
Creator: Srinivasan, Ashok
Object Type: Report
System: The UNT Digital Library
Measurement/Evaluation Techniques and Nuclear Data Associated with Fission of 239Pu by Fission Spectrum Neutrons (open access)

Measurement/Evaluation Techniques and Nuclear Data Associated with Fission of 239Pu by Fission Spectrum Neutrons

This Panel was chartered to review and assess new evaluations of work on fission product data, as well as the evaluation process used by the two U.S. nuclear weapons physics laboratories. The work focuses on fission product yields resulting from fission spectrum neutrons incident on plutonium, and includes data from measurements that had not been previously published as well as new or revised fission product cumulative yield data, and related quantities such as Q values and R values. This report documents the Panel's assessment of the work presented by Los Alamos National Laboratory (LANL) and Lawrence Livermore National Laboratory (LLNL). Based on the work presented we have seven key observations: (1) Experiments conducted in the 1970s at LANL, some of which were performed in association with a larger, NIST-led, program, have recently been documented. A preliminary assessment of this work, which will be referred to in this document as ILRR-LANL, shows it to be technically sound. (2) LLNL has done a thorough, unbiased review and evaluation of the available literature and is in the process of incorporating the previously unavailable LANL data into its evaluation of key fission product yields. The results of the LLNL effort, which includes a preliminary …
Date: March 16, 2010
Creator: Baisden, Patricia; Bauge, Eric; Ferguson, James; Gilliam, David; Granier, Thierry; Jeanloz, Raymond et al.
Object Type: Report
System: The UNT Digital Library
Low Strain Rate Measurements on Explosives Using DIC (open access)

Low Strain Rate Measurements on Explosives Using DIC

None
Date: March 16, 2010
Creator: Cunningham, B J; Gagliardi, F J & Ferranti, L
Object Type: Article
System: The UNT Digital Library
Direction-Preserving and Schur-Monotonic Semi-Separable Approximations of Symmetric Positive Definite Matrices} (open access)

Direction-Preserving and Schur-Monotonic Semi-Separable Approximations of Symmetric Positive Definite Matrices}

For a given symmetric positive definite matrix A {element_of} R{sup N x N}, we develop a fast and backward stable algorithm to approximate A by a symmetric positive-definite semi-separable matrix, accurate to a constant multiple of any prescribed tolerance. In addition, this algorithm preserves the product, AZ, for a given matrix Z {element_of} R{sup N x d}, where d << N. Our algorithm guarantees the positive-definiteness of the semi-separable matrix by embedding an approximation strategy inside a Cholesky factorization procedure to ensure that the Schur complements during the Cholesky factorization all remain positive definite after approximation. It uses a robust direction-preserving approximation scheme to ensure the preservation of AZ. We present numerical experiments and discuss potential implications of our work.
Date: March 16, 2010
Creator: Gu, M.; Li, X. S. & Vassilevski, P. S.
Object Type: Article
System: The UNT Digital Library
Surface current reduction of (211) oriented Cd0.46Zn0.04Te0.50 crystals by Ar bombardment (open access)

Surface current reduction of (211) oriented Cd0.46Zn0.04Te0.50 crystals by Ar bombardment

Cd{sub 0.46}Zn{sub 0.04}Te{sub .50} crystals have been exposed to high density Ar plasmas in order to modify the surface chemistry and control the surface conductivity. X-ray photoelectron spectroscopy (XPS) reveals that this bombardment results in a modified surface atomic ratio, with Cd being preferentially removed compared to Te. In addition, the native oxide is removed and suppressed for an extended period of time. Current-voltage data is analyzed in order to determine the effect on surface leakage current after exposure. It is found that surface leakage current can be decreased by approximately 2.5 orders of magnitude following Ar{sup +} bombardment.
Date: March 16, 2010
Creator: Voss, L F; Beck, P R; Conway, A M; Graff, R T; Nikolic, R J; Nelson, A J et al.
Object Type: Article
System: The UNT Digital Library