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Search for B-meson decays to b1rho and b1K___ (open access)

Search for B-meson decays to b1rho and b1K___

We present a search for decays of B mesons to final states with a b{sub 1} meson and a {rho} or K*(892) meson. The search is based on a data sample consisting of 465 million B{bar B} pairs collected by the BABAR detector at the SLAC National Accelerator Laboratory. We do not observe any statistically significant signal. The upper limits we set on the branching fractions range from 1.4 to 8.0 x 10{sup -6} at the 90% confidence level (C.L.), including systematic uncertainties.
Date: June 11, 2010
Creator: Aubert, Bernard; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
Searches for Lepton Flavor Violation in the Decays tau+- ---> e+- gamma and tau+- ---> mu+- gamma (open access)

Searches for Lepton Flavor Violation in the Decays tau+- ---> e+- gamma and tau+- ---> mu+- gamma

Searches for lepton-flavor-violating decays of a {tau} lepton to a lighter mass lepton and a photon have been performed with the entire dataset of (963 {+-} 7) x 10{sup 6} {tau} decays collected by the BABAR detector near the {Upsilon}(4S), {Upsilon}(3S) and {Upsilon}(2S) resonances. The searches yield no evidence of signals and they set upper limits on the branching fractions of {Beta}({tau}{sup {+-}} {yields} e{sup {+-}}{gamma}) < 3.3 x 10{sup -8} and {Beta}({tau}{sup {+-}} {yields} {mu}{sup {+-}}{gamma}) < 4.4 x 10{sup -8} at 90% confidence level.
Date: June 11, 2010
Creator: Aubert, Bernard; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
FY2010 Supplemental for Wars, Disaster Assistance, Haiti Relief, and Other Programs (open access)

FY2010 Supplemental for Wars, Disaster Assistance, Haiti Relief, and Other Programs

This report discusses the $64 billion in requested supplemental appropriations for FY2010, which includes $2.8 billion for Haiti earthquake-related reconstruction and foreign aid and $243 million for activities related to the Deepwater Horizon oil spill and more.
Date: June 11, 2010
Creator: Belasco, Amy; Else, Daniel H.; Lindsay, Bruce R.; Margesson, Rhoda; Nakamura, Kennon H. & Taft-Morales, Maureen
Object Type: Report
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
Verification of an IGBT Fusing Switch for Over-current Protection of the SNS HVCM (open access)

Verification of an IGBT Fusing Switch for Over-current Protection of the SNS HVCM

An IGBT based over-current protection system has been developed to detect faults and limit the damage caused by faults in high voltage converter modulators. During normal operation, an IGBT enables energy to be transferred from storage capacitors to a H-bridge. When a fault occurs, the over-current protection system detects the fault, limits the fault current and opens the IGBT to isolate the remaining stored energy from the fault. This paper presents an experimental verification of the over-current protection system under applicable conditions.
Date: June 11, 2010
Creator: Benwell, Andrew; Kemp, Mark; Burkhart, Craig & Nguyen, Minh
Object Type: Article
System: The UNT Digital Library
Intelligence Issues for Congress (open access)

Intelligence Issues for Congress

This report discusses the efforts currently underway to improve coordination and encourage better analysis amongst the various agencies within the U.S. Intelligence Community, especially with regard to the ongoing and prominent issue of international terrorism. In particular, this report addresses the false intelligence regarding Iraqi weapons of mass destruction and the current efforts in Iraq and Iran in general.
Date: June 11, 2010
Creator: Best, Richard A., Jr.
Object Type: Report
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
Single Particle Difraction at FLASH (open access)

Single Particle Difraction at FLASH

Single-pulse coherent diffraction patterns have been collected from randomly injected single particles with a soft X-ray free-electron laser (FEL). The intense focused FEL pulse gives a high-resolution low-noise coherent diffraction pattern of the object before that object turns into a plasma and explodes. A diffraction pattern of a single particle will only be recorded when the particle arrival into the FEL interaction region coincides with FEL pulse arrival and detector integration. The properties of the experimental apparatus coinciding with these three events set the data acquisition rate. For our single particle FLASH diffraction imaging experiments: (1) an aerodynamic lens stack prepared a particle beam that consisted of particles moving at 150-200 m/s positioned randomly in space and time, (2) the 10 fs long FEL pulses were delivered at a fixed rate, and (3) the detector was set to integrate and readout once every two seconds. The effect of these experimental parameters on the rate of data acquisition using randomly injected particles will be discussed. Overall, the ultrashort FEL pulses do not set the limit of the data acquisition, more important is the effective interaction time of the particle crossing the FEL focus, the pulse sequence structure and the detector readout …
Date: June 11, 2010
Creator: Bogan, M.; Boutet, S.; Starodub, Dmitri; Decorwin-Martin, Philippe; /SLAC; Chapman, H. et al.
Object Type: Article
System: The UNT Digital Library
The Role of INSPIRE in HEP Data Preservation Efforts (open access)

The Role of INSPIRE in HEP Data Preservation Efforts

INSPIRE is a new community resource for HEP literature and associated information. It is based on the combination of SPIRES content and features and the powerful Invenio software developed at CERN. The INSPIRE service will come online in fall of 2009, and be run by CERN, DESY, Fermilab and SLAC. Data preservation, to be successful, must not only preserve the data, but must also organize it and allow it to be found by those who would make use of it, and resources such as INSPIRE are ideally positioned and ready to provide this organization and context. In addition, INSPIRE will soon be ready to provide storage of smaller datasets, such as high-level analysis objects, as stand-alone objects placed in the repository or as objects associated with an analysis paper. This small project could pave the way towards the context and organization which is one piece of the infrastructure needed for all levels of data preservation.
Date: June 11, 2010
Creator: Brooks, Travis C.
Object Type: Article
System: The UNT Digital Library
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 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 Endangered Species Act (ESA) in the 111th Congress: Conflicting Values and Difficult Choices (open access)

The Endangered Species Act (ESA) in the 111th Congress: Conflicting Values and Difficult Choices

None
Date: June 11, 2010
Creator: Buck, Eugene H.; Corn, M. Lynne; Sheikh, Pervaze A.; Meltz, Robert & Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
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
Finding the Higgs boson of the standard model in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ with the D0 detector at the Tevatron; Recherche du boson de Higgs du nideke standard dans le canal ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ Avec le Detecteur DØ Aupres du Tevatron (open access)

Finding the Higgs boson of the standard model in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ with the D0 detector at the Tevatron; Recherche du boson de Higgs du nideke standard dans le canal ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ Avec le Detecteur DØ Aupres du Tevatron

The organization of this thesis consists of three main ideas: the first presents the theoretical framework and experimental, as well as objects used in the analysis and the second relates to the various work tasks of service that I performed on the calorimeter, and the third is the search for the Higgs boson in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$. Thus, this thesis has the following structure: Chapter 1 is an introduction to the standard model of particle physics and the Higgs mechanism; Chapter 2 is an overview of the complex and the acceleration of the Tevatron at Fermilab DØ detector; Chapter 3 is an introduction to physical objects used in this thesis; Chapter 4 presents the study made on correcting the energy measured in the calorimeter; Chapter 5 describes the study of certification of electrons in the calorimeter; Chapter 6 describes the study of certification of electrons in the intercryostat region of calorimeter; Chapter 7 Detailed analysis on the search for Higgs production in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$; and Chapter 8 presents the final results of the calculations of upper limits to the production cross section of the Higgs boson on a range of low masses.
Date: June 11, 2010
Creator: Calpas, Betty Constante
Object Type: Thesis or Dissertation
System: The UNT Digital Library
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
Japan-U.S. Relations: Issues for Congress (open access)

Japan-U.S. Relations: Issues for Congress

This report discusses the relationship between the United States and Japan, including Japanese efforts to support the U.S. in the wake of the September 11th, 2001 terrorist attacks and the two countries' economic ties, especially with regards to the recent economic downturn. This report also discusses the general political atmosphere of Japan, including the recent and ongoing political turmoil in Tokyo.
Date: June 11, 2010
Creator: Chanlett-Avery, Emma; Cooper, William H. & Manyin, Mark E.
Object Type: Report
System: The UNT Digital Library
Leptonic Decays of the Charged B Meson (open access)

Leptonic Decays of the Charged B Meson

The authors present a search for the decay B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} ({ell} = {tau}, {mu}, or e) in (458.9 {+-} 5.1) x 10{sup 6} {Upsilon}(4S) decays recorded with the BABAR detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed exclusive semi-leptonic B decay (B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}X) is selected, and in the recoil a search for B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} signal is performed. The {tau} is identified in the following channels: {tau}{sup +} {yields} e{sup +}{nu}{sub e}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {mu}{sup +}{nu}{sub {mu}}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {pi}{sup +}{bar {nu}}{sub {tau}}, and {tau}{sup +} {yields} {pi}{sup +}{pi}{sup 0}{bar {nu}}{sub {tau}}. The analysis strategy and the statistical procedure is set up for branching fraction extraction or upper limit determination. They determine from the dataset a preliminary measurement of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = (1.8 {+-} 0.8 {+-} 0.1) x 10{sup -4}, which excludes zero at 2.4{sigma}, and f{sub B} = 255 {+-} 58 MeV. Combination with the hadronically tagged measurement yields {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = (1.8 {+-} 0.6) x 10{sup -4}. They also set preliminary limits on the branching fractions at …
Date: June 11, 2010
Creator: Corwin, Luke A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
ENDF Cross Sections are not Uniquely Defined (open access)

ENDF Cross Sections are not Uniquely Defined

None
Date: June 11, 2010
Creator: Cullen, D E
Object Type: Report
System: The UNT Digital Library
From the LHC to Future Colliders (open access)

From the LHC to Future Colliders

Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300 fb{sup -1} of integrated luminosity, of the proposed sLHC luminosity upgrade, of the ILC, of CLIC, of the LHeC and of a muon collider. The four Working Groups considered possible scenarios for the first 10 fb{sup -1} of data at the LHC in which (i) a state with properties that are compatible with a Higgs boson is discovered, (ii) no such state is discovered either because the Higgs properties are such that it is difficult to detect or because no Higgs boson exists, (iii) a missing-energy signal beyond the Standard Model is discovered as in some supersymmetric models, and (iv) some other exotic signature of new physics is discovered. In the contexts of these scenarios, theWorking Groups reviewed the capabilities of the future colliders to study in more detail whatever new physics may be discovered by the LHC. Their reports provide the particle physics community with some tools for reviewing the scientific priorities for future colliders after the LHC produces …
Date: June 11, 2010
Creator: De Roeck, A.; Ellis, J.; Grojean, C.; Heinemeyer, S.; Jakobs, K.; Weiglein, G. et al.
Object Type: Article
System: The UNT Digital Library

Effect of System and Air Contaminants on PEMFC Performance and Durability

This presentation summarizes Effect of System and Air Contaminants on PEMFC Performance and Durability.
Date: June 11, 2010
Creator: Dinh, H.
Object Type: Presentation
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
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}&gt; 6 x 10{sup -8} {alpha} to electrons ({alpha} = e{sup 2}/4{pi}) in the mass range 65 MeV &lt; m{sub A'} &lt; 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
Iraq Casualties: U.S. Military Forces and Iraqi Civilians, Police, and Security Forces (open access)

Iraq Casualties: U.S. Military Forces and Iraqi Civilians, Police, and Security Forces

This report presents U.S. military casualties as well as governmental and nongovernmental estimates of Iraqi civilian, police, and security forces casualties.
Date: June 11, 2010
Creator: Fischer, Hannah
Object Type: Report
System: The UNT Digital Library
2010 MULTIPHOTON PROCESSES GORDON RESEARCH CONFERENCE, JUNE 6-11, 2010, TILTON, NH (open access)

2010 MULTIPHOTON PROCESSES GORDON RESEARCH CONFERENCE, JUNE 6-11, 2010, TILTON, NH

The Gordon Research Conference on Multiphoton Processes will be held for the 15th time in 2010. The meeting continues to evolve as it embraces both the rapid technological and intellectual growth in the field as well as the multi-disciplinary expertise of the participants. This time the sessions will focus on: (1) Ultrafast coherent control; (2) Free-electron laser experiments and theory; (3) Generation of harmonics and attosecond pulses; (4) Ultrafast imaging; (5) Applications of very high intensity laser fields; (6) Strong-field processes in molecules and solids; (7) Attosecond science; and (8) Controlling light. The scientific program will blur traditional disciplinary boundaries as the presenters and discussion leaders involve chemists, physicists, and optical engineers, representing both experiment and theory. The broad range of expertise and different perspectives of attendees should provide a stimulating and unique environment for solving problems and developing new ideas in this rapidly evolving field.
Date: June 11, 2010
Creator: Gaarde, Mette
Object Type: Article
System: The UNT Digital Library