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The Boerne Star (Boerne, Tex.), Vol. 104, No. 47, Ed. 1 Friday, June 11, 2010 (open access)

The Boerne Star (Boerne, Tex.), Vol. 104, No. 47, Ed. 1 Friday, June 11, 2010

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Cartwright, Brian & Velvin, Candace E.
Object Type: Newspaper
System: The Portal to Texas History
Perry Daily Journal (Perry, Okla.), Vol. 118, No. 113, Ed. 1 Friday, June 11, 2010 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 118, No. 113, Ed. 1 Friday, June 11, 2010

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 112, No. 134, Ed. 1 Friday, June 11, 2010 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 134, Ed. 1 Friday, June 11, 2010

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The GV Tribune (Grandview, Tex.), Vol. 115, No. 24, Ed. 1 Friday, June 11, 2010 (open access)

The GV Tribune (Grandview, Tex.), Vol. 115, No. 24, Ed. 1 Friday, June 11, 2010

Weekly newspaper from Grandview, Texas that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Buck, Erin
Object Type: Newspaper
System: The Portal to Texas History
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, June 11, 2010 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, June 11, 2010

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Wray, Kelly
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Oklahoma Eagle (Tulsa, Okla.), Vol. 90, No. 24, Ed. 1 Friday, June 11, 2010 (open access)

The Oklahoma Eagle (Tulsa, Okla.), Vol. 90, No. 24, Ed. 1 Friday, June 11, 2010

Weekly newspaper from Tulsa, Oklahoma that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 90, No. 116, Ed. 1 Friday, June 11, 2010 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 90, No. 116, Ed. 1 Friday, June 11, 2010

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Halter, Janie
Object Type: Newspaper
System: The Portal to Texas History
Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 54, No. 30, Ed. 1 Friday, June 11, 2010 (open access)

Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 54, No. 30, Ed. 1 Friday, June 11, 2010

Weekly newspaper from Dell City, Texas that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Stuart, Andrew
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 192, Ed. 1 Friday, June 11, 2010 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 192, Ed. 1 Friday, June 11, 2010

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: June 11, 2010
Creator: Shance, Brenda
Object Type: Newspaper
System: The Gateway to Oklahoma History
Flavour-Violating Gluino and Squark Decays (open access)

Flavour-Violating Gluino and Squark Decays

We consider scenarios with large flavour violating entries in the squark mass matrices focusing on the mixing between second and third generation squarks. These entries govern both, flavour violating low energy observables on the one hand and squark and gluino decays on the other hand. We first discuss the constraints on the parameter space due to the recent data on B mesons from the B factories and Tevatron. We then consider flavour violating squark and gluino decays and show that they can still be typically of order 10% despite the stringent constraints from low energy data. Finally we briefly comment on the impact for searches and parameter determinations at future collider experiments such as the upcoming LHC or a future International Linear Collider.
Date: June 11, 2010
Creator: Hurth, Tobias & Porod, Werner
Object Type: Article
System: The UNT Digital Library
Dual Selectivity Expressed in [2+2+1] Dynamic Clipping of Unsymmetrical [2]Catenanes (open access)

Dual Selectivity Expressed in [2+2+1] Dynamic Clipping of Unsymmetrical [2]Catenanes

A {pi}-templated dynamic [2+2+1] clipping protocol is established for the synthesis of [2]catenanes from two parts dialdehyde, two parts diamine and one part tetracationic cyclophane. It is further diversified for the selective formation of an unsymmetrical [2]catenane showing great translational selectivity by employing two different dialdehydes in a one-pot reaction. The dual selectivity and the dynamic nature are verified by {sup 1}H NMR spectroscopy, X-ray single crystal structural studies and exchange experiments.
Date: June 11, 2010
Creator: Liu, Yi
Object Type: Article
System: The UNT Digital Library
Commissioning of the LCLS LINAC (open access)

Commissioning of the LCLS LINAC

The Linac Coherent Light Source (LCLS) X-ray free electron laser project is currently under construction at the Stanford Linear Accelerator Center (SLAC). A new injector and upgrades to the existing accelerator were installed in two phases in 2006 and 2007. We report on the commissioning of the injector, the two new bunch compressors at 250MeV and 4.3 GeV, and transverse and longitudinal beam diagnostics up to the end of the existing linac at 13.6 GeV. The commissioning of the new transfer line from the end of the linac to the undulator is scheduled to start in November 2008 and for the undulator in March 2009 with first light to be expected in July 2009.
Date: June 11, 2010
Creator: Loos, H.; Akre, R.; Brachmann, A.; Decker, F. J.; Ding, Y.; Dowell, D. et al.
Object Type: Article
System: The UNT Digital Library
Cosmic Ray Spectra in Nambu-Goldstone Dark Matter Models (open access)

Cosmic Ray Spectra in Nambu-Goldstone Dark Matter Models

We discuss the cosmic ray spectra in annihilating/decaying Nambu-Goldstone dark matter models. The recent observed positron/electron excesses at PAMELA and Fermi experiments are well fitted by the dark matter with a mass of 3TeV for the annihilating model, while with a mass of 6TeV for the decaying model. We also show that the Nambu-Goldstone dark matter models predict a distinctive gamma-ray spectrum in a certain parameter space.
Date: June 11, 2010
Creator: Ibe, Masahiro; Murayama, Hitoshi; Shirai, Satoshi & Yanagida, Tsutomu T.
Object Type: Article
System: The UNT Digital Library
SLAC Next-Generation High Availability Power Supply (open access)

SLAC Next-Generation High Availability Power Supply

SLAC recently commissioned forty high availability (HA) magnet power supplies for Japan's ATF2 project. SLAC is now developing a next-generation N+1 modular power supply with even better availability and versatility. The goal is to have unipolar and bipolar output capability. It has novel topology and components to achieve very low output voltage to drive superconducting magnets. A redundant, embedded, digital controller in each module provides increased bandwidth for use in beam-based alignment, and orbit correction systems. The controllers have independent inputs for connection to two external control nodes. Under fault conditions, they sense failures and isolate the modules. Power supply speed mitigates the effects of fault transients and obviates subsequent magnet standardization. Hot swap capability promises higher availability and other exciting benefits for future, more complex, accelerators, and eventually the International Linear Collider project.
Date: June 11, 2010
Creator: Bellomo, P. & MacNair, D.
Object Type: Article
System: The UNT Digital Library
Compliance and Verification of Standards and Labelling Programs in China: Lessons Learned (open access)

Compliance and Verification of Standards and Labelling Programs in China: Lessons Learned

After implementing several energy efficiency standards and labels (30 products covered by MEPS, 50 products covered by voluntary labels and 19 products by mandatory labels), the China National Institute of Standardization (CNIS) is now implementing verification and compliance mechanism to ensure that the energy information of labeled products comply with the requirements of their labels. CNIS is doing so by organizing check testing on a random basis for room air-conditioners, refrigerators, motors, heaters, computer displays, ovens, and self -ballasted lamps. The purpose of the check testing is to understand the implementation of the Chinese labeling scheme and help local authorities establishing effective compliance mechanisms. In addition, to ensure robustness and consistency of testing results, CNIS has coordinated a round robin testing for room air conditioners. Eight laboratories (Chinese (6), Australian (1) and Japanese (1)) have been involved in the round robin testing and tests were performed on four sets of samples selected from manufacturer?s production line. This paper describes the methodology used in undertaking both check and round robin testing, provides analysis of testing results and reports on the findings. The analysis of both check and round robin testing demonstrated the benefits of a regularized verification and monitoring system for …
Date: June 11, 2010
Creator: Saheb, Yamina; Zhou, Nan; Fridley, David & Pierrot, André
Object Type: Article
System: The UNT Digital Library
Physics considerations for laser-plasma linear colliders (open access)

Physics considerations for laser-plasma linear colliders

Physics considerations for a next-generation linear collider based on laser-plasma accelerators are discussed. The ultra-high accelerating gradient of a laser-plasma accelerator and short laser coupling distance between accelerator stages allows for a compact linac. Two regimes of laser-plasma acceleration are discussed. The highly nonlinear regime has the advantages of higher accelerating fields and uniform focusing forces, whereas the quasi-linear regime has the advantage of symmetric accelerating properties for electrons and positrons. Scaling of various accelerator and collider parameters with respect to plasma density and laser wavelength are derived. Reduction of beamstrahlung effects implies the use of ultra-short bunches of moderate charge. The total linac length scales inversely with the square root of the plasma density, whereas the total power scales proportional to the square root of the density. A 1 TeV center-of-mass collider based on stages using a plasma density of 10{sup 17} cm{sup -3} requires tens of J of laser energy per stage (using 1 {micro}m wavelength lasers) with tens of kHz repetition rate. Coulomb scattering and synchrotron radiation are examined and found not to significantly degrade beam quality. A photon collider based on laser-plasma accelerated beams is also considered. The requirements for the scattering laser energy are comparable …
Date: June 11, 2010
Creator: Schroeder, Carl; Esarey, Eric; Geddes, Cameron; Benedetti, Carlo & Leemans, Wim
Object Type: Article
System: The UNT Digital Library
Signals of New Physics in the Underlying Event (open access)

Signals of New Physics in the Underlying Event

LHC searches for new physics focus on combinations of hard physics objects. In this work we propose a qualitatively different soft signal for new physics at the LHC - the 'anomalous underlying event'. Every hard LHC event will be accompanied by a soft underlying event due to QCD and pile-up effects. Though it is often used for QCD and monte carlo studies, here we propose the incorporation of an underlying event analysis in some searches for new physics. An excess of anomalous underlying events may be a smoking-gun signal for particular new physics scenarios such as 'quirks' or 'hidden valleys' in which large amounts of energy may be emitted by a large multiplicity of soft particles. We discuss possible search strategies for such soft diffuse signals in the tracking system and calorimetry of the LHC experiments. We present a detailed study of the calorimetric signal in a concrete example, a simple quirk model motivated by folded supersymmetry. In these models the production and radiative decay of highly excited quirk bound states leads to an 'antenna pattern' of soft unclustered energy. Using a dedicated simulation of a toy detector and a 'CMB-like' multipole analysis we compare the signal to the expected …
Date: June 11, 2010
Creator: Harnik, Roni & Wizansky, Tommer
Object Type: Article
System: The UNT Digital Library
An Electron Fixed Target Experiment to Search for a New Vector Boson A' Decaying to e+e- (open access)

An Electron Fixed Target Experiment to Search for a New Vector Boson A' Decaying to e+e-

We describe an experiment to search for a new vector boson A' with weak coupling {alpha}' {approx}> 6 x 10{sup -8} {alpha} to electrons ({alpha} = e{sup 2}/4{pi}) in the mass range 65 MeV < m{sub A'} < 550 MeV. New vector bosons with such small couplings arise naturally from a small kinetic mixing of the 'dark photon' A' with the photon - one of the very few ways in which new forces can couple to the Standard Model - and have received considerable attention as an explanation of various dark matter related anomalies. A' bosons are produced by radiation off an electron beam, and could appear as narrow resonances with small production cross-section in the trident e{sup +}e{sup -} spectrum. We summarize the experimental approach described in a proposal submitted to Jefferson Laboratory's PAC35, PR-10-009. This experiment, the A' Experiment (APEX), uses the electron beam of the Continuous Electron Beam Accelerator Facility at Jefferson Laboratory (CEBAF) at energies of {approx} 1-4 GeV incident on 0.5-10% radiation length Tungsten wire mesh targets, and measures the resulting e{sup +}e{sup -} pairs to search for the A' using the High Resolution Spectrometer and the septum magnet in Hall A. With a {approx} …
Date: June 11, 2010
Creator: Essig, Rouven; Schuster, Philip; Toro, Natalia & Wojtsekhowski, Bogdan
Object Type: Article
System: The UNT Digital Library
Small Steps Towards a Grand Unification and the Electron/Positron Excesses in Cosmic-Ray Experiments (open access)

Small Steps Towards a Grand Unification and the Electron/Positron Excesses in Cosmic-Ray Experiments

We consider a small extension of the standard model by adding two Majorana fermions; those are adjoint representations of the SU(2){sub L} and SU(3){sub c} gauge groups of the standard model. In this extension, the gauge coupling unification at an energy scale higher than 10{sup 15} GeV is realized when the masses of the triplet and the octet fermions are smaller than 10{sup 4} GeV and 10{sup 12} GeV, respectively. We also show that an appropriate symmetry ensures a long lifetime of the neutral component of the triplet fermion whose thermal relic density naturally explains the observed dark matter density. The electron/positron excesses observed in recent cosmic-ray experiments can be also explained by the decay of the triplet fermion.
Date: June 11, 2010
Creator: Ibe, Masahiro
Object Type: Article
System: The UNT Digital Library
Single Ion Implantation and Deterministic Doping (open access)

Single Ion Implantation and Deterministic Doping

The presence of single atoms, e.g. dopant atoms, in sub-100 nm scale electronic devices can affect the device characteristics, such as the threshold voltage of transistors, or the sub-threshold currents. Fluctuations of the number of dopant atoms thus poses a complication for transistor scaling. In a complementary view, new opportunities emerge when novel functionality can be implemented in devices deterministically doped with single atoms. The grand price of the latter might be a large scale quantum computer, where quantum bits (qubits) are encoded e.g. in the spin states of electrons and nuclei of single dopant atoms in silicon, or in color centers in diamond. Both the possible detrimental effects of dopant fluctuations and single atom device ideas motivate the development of reliable single atom doping techniques which are the subject of this chapter. Single atom doping can be approached with top down and bottom up techniques. Top down refers to the placement of dopant atoms into a more or less structured matrix environment, like a transistor in silicon. Bottom up refers to approaches to introduce single dopant atoms during the growth of the host matrix e.g. by directed self-assembly and scanning probe assisted lithography. Bottom up approaches are discussed in …
Date: June 11, 2010
Creator: Schenkel, Thomas
Object Type: Book
System: The UNT Digital Library
PROBING STRESS EFFECTS IN SINGLE CRYSTAL ORGANIC TRANSISTORS BY SCANNING KELVIN PROBE MICROSCOPY (open access)

PROBING STRESS EFFECTS IN SINGLE CRYSTAL ORGANIC TRANSISTORS BY SCANNING KELVIN PROBE MICROSCOPY

We report scanning Kelvin probe microscopy (SKPM) of single crystal difluoro bis(triethylsilylethynyl) anthradithiophene (diF-TESADT) organic transistors. SKPM provides a direct measurement of the intrinsic charge transport in the crystals independent of contact effects and reveals that degradation of device performance occurs over a time period of minutes as the diF-TESADT crystal becomes charged.
Date: June 11, 2010
Creator: Teague, L.
Object Type: Article
System: The UNT Digital Library
New Fixed-Target Experiments to Search for Dark Gauge Forces (open access)

New Fixed-Target Experiments to Search for Dark Gauge Forces

Fixed-target experiments are ideally suited for discovering new MeV-GeV mass U(1) gauge bosons through their kinetic mixing with the photon. In this paper, we identify the production and decay properties of new light gauge bosons that dictate fixed-target search strategies. We summarize existing limits and suggest five new experimental approaches that we anticipate can cover most of the natural parameter space, using currently operating GeV-energy beams and well-established detection methods. Such experiments are particularly timely in light of recent terrestrial and astrophysical anomalies (PAMELA, FERMI, DAMA/LIBRA, etc.) consistent with dark matter charged under a new gauge force.
Date: June 11, 2010
Creator: Bjorken, James D.; Essig, Rouven; Schuster, Philip & Toro, Natalia
Object Type: Article
System: The UNT Digital Library
Studying Gaugino mass in Semi-Direct Gauge Mediation (open access)

Studying Gaugino mass in Semi-Direct Gauge Mediation

We study gaugino mass generation in the context of semi-direct gauge mediation models, where the messengers are charged under both the hidden sector and the standard model gauge groups while they do not play important roles in dynamical supersymmetry breaking. We clarify the cancellation of the leading contributions of the supersymmetry breaking effects to the gaugino mass in this class of models in terms of the macroscopic effective theory of the hidden sector dynamics. We also consider how to retrofit the model so that we obtain the non-vanishing leading contribution to the gaugino mass.
Date: June 11, 2010
Creator: Ibe, M.; Izawa, K. -I. & Nakai, Y.
Object Type: Report
System: The UNT Digital Library

Novel Approach to Advanced Direct Methanol Fuel Cell Anode Catalysts

This presentation is a summary of a Novel Approach to Advanced Direct Methanol Fuel Cell Anode Catalysts.
Date: June 11, 2010
Creator: Dinh, H. & Gennett, T.
Object Type: Presentation
System: The UNT Digital Library