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Discovery of Very High Energy Gamma Rays from PKS 1424+240 and Multiwavelength Constraints on its Redshift (open access)

Discovery of Very High Energy Gamma Rays from PKS 1424+240 and Multiwavelength Constraints on its Redshift

We report the first detection of very-high-energy (VHE) gamma-ray emission above 140GeV from PKS 1424+240, a BL Lac object with an unknown redshift. The photon spectrum above 140GeV measured by VERITAS is well described by a power law with a photon index of 3.8 {+-}0.5{sub stat} {+-} 0.3{sub syst} and a flux normalization at 200 GeV of (5.1 {+-} 0.9{sub stat} {+-} 0.5{sub syst}) x 10{sup -11} TeV{sup -1} cm{sup -2} s{sup -1}, where stat and syst denote the statistical and systematical uncertainty, respectively. The VHE flux is steady over the observation period between MJD 54881 and 55003 (2009 February 19 to June 21). Flux variability is also not observed in contemporaneous high energy observations with the Fermi Large Area Telescope (LAT). Contemporaneous X-ray and optical data were also obtained from the Swift XRT and MDM observatory, respectively. The broadband spectral energy distribution (SED) is well described by a one-zone synchrotron self-Compton (SSC) model favoring a redshift of less than 0.1. Using the photon index measured with Fermi in combination with recent extragalactic background light (EBL) absorption models it can be concluded from the VERITAS data that the redshift of PKS 1424+240 is less than 0.66.
Date: April 5, 2012
Creator: Acciari, V. A.; Aliu, E.; Arlen, T.; Aune, T.; Bautista, M.; Beilicke, M. et al.
Object Type: Report
System: The UNT Digital Library

Master's Recital: 2012-04-05 - Eric Andress, bass trombone

Access: Use of this item is restricted to the UNT Community
Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Master of Music (MM) degree.
Date: April 5, 2012
Creator: Andress, Eric Matthew
Object Type: Sound
System: The UNT Digital Library
The European Union: Questions and Answers (open access)

The European Union: Questions and Answers

This report provides a brief overview of the European Union (EU), an economic and political partnership between 27 sovereign member states. The report describes the formation of the EU, the three main institutions of the EU, and the EU's relationship with the United States.
Date: April 5, 2012
Creator: Archick, Kristin
Object Type: Report
System: The UNT Digital Library
Western Sahara (open access)

Western Sahara

This report discusses how Morocco and the independence-seeking Popular Front for the Liberation of Saqiat al Hamra and Rio de Oro (Polisario) have been vying for control of the Western Sahara, a former Spanish territory, since the 1970s. The report discusses recent settlement attempts, as well as how the Western Sahara issue has affected Algerian-Moroccan bilaterial relations, Moroccan relations with the African Union, and regional cooperation on economic and security issues. The report also discusses the United States' involvement in and stance on the issue.
Date: April 5, 2012
Creator: Arieff, Alexis
Object Type: Report
System: The UNT Digital Library
Oral History Interview with Gayle Reaves-King, April 4, 2012 (open access)

Oral History Interview with Gayle Reaves-King, April 4, 2012

Interview with Gayle Reaves-King,a journalist in Fort Worth, Texas. The interview includes biographical information about her life growing up, her educational background, family life, and her career with The Dallas Morning News and other newspapers.
Date: April 5, 2012
Creator: Ayers, Cesta & Reaves-King, Gayle
Object Type: Text
System: The UNT Digital Library

Doctoral Recital: 2012-04-05 - Tyrone Block, bass trombone

Recital presented at the UNT College of Music Voertman Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date: April 5, 2012
Creator: Block, Tyrone
Object Type: Sound
System: The UNT Digital Library
The Canadian Record (Canadian, Tex.), Vol. 122, No. 14, Ed. 1 Thursday, April 5, 2012 (open access)

The Canadian Record (Canadian, Tex.), Vol. 122, No. 14, Ed. 1 Thursday, April 5, 2012

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: April 5, 2012
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
The Repeal of "Don't Ask, Don't Tell": Issues for Congress (open access)

The Repeal of "Don't Ask, Don't Tell": Issues for Congress

On December 22, 2010, President Obama signed into law legislation calling for the repeal of the existing law barring open homosexuality in the military by prescribing a series of steps that must take place before repeal occurs. One step was fulfilled on July 22, 2011, when the President signed the certification of the process ending the Don't Ask, Don't Tell policy, which was repealed on September 20, 2011. This report considers issues that Congress may wish to consider as the repeal process proceeds.
Date: April 5, 2012
Creator: Burrelli, David F.
Object Type: Report
System: The UNT Digital Library
Women in Combat: Issues for Congress (open access)

Women in Combat: Issues for Congress

This report looks at the history of women in US military roles and combat since the 1990's. It also discusses critic's views of exclusionary policy as a civil rights issue.
Date: April 5, 2012
Creator: Burrelli, David F.
Object Type: Report
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 112, No. 257, Ed. 1 Thursday, April 5, 2012 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 257, Ed. 1 Thursday, April 5, 2012

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: April 5, 2012
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Army Corps of Engineers’ Nationwide Permits Program: Issues and Regulatory Developments (open access)

The Army Corps of Engineers’ Nationwide Permits Program: Issues and Regulatory Developments

This report contains the issues and regulatory developments in the army corps engineers' nationwide permits program.
Date: April 5, 2012
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Water Infrastructure Financing: History of EPA Appropriations (open access)

Water Infrastructure Financing: History of EPA Appropriations

None
Date: April 5, 2012
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Thursday, April 5, 2012 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Thursday, April 5, 2012

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: April 5, 2012
Creator: DeSilver, Debi
Object Type: Newspaper
System: The Gateway to Oklahoma History
Unitarity Bounds and RG Flows in Time Dependent Quantum Field Theory (open access)

Unitarity Bounds and RG Flows in Time Dependent Quantum Field Theory

We generalize unitarity bounds on operator dimensions in conformal field theory to field theories with spacetime dependent couplings. Below the energy scale of spacetime variation of the couplings, their evolution can strongly affect the physics, effectively shifting the infrared operator scaling and unitarity bounds determined from correlation functions in the theory. We analyze this explicitly for large-N double-trace flows, and connect these to UV complete field theories. One motivating class of examples comes from our previous work on FRW holography, where this effect explains the range of flavors allowed in the dual, time dependent, field theory.
Date: April 5, 2012
Creator: Dong, Xi; Horn, Bart; Silverstein, Eva; Torroba, Gonzalo & /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC
Object Type: Report
System: The UNT Digital Library
Canada-U.S. Relations (open access)

Canada-U.S. Relations

This report begins with a short overview of Canada's political scene, economic conditions, security, foreign policy, and discusses Canada - U.S relations.
Date: April 5, 2012
Creator: Ek, Carl & Fergusson, Ian F.
Object Type: Report
System: The UNT Digital Library
Muon Muon Collider: Feasibility Study (open access)

Muon Muon Collider: Feasibility Study

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be …
Date: April 5, 2012
Creator: Gallardo, J. C.; Palmer, R. B.; Tollestrup, A. V.; Sessler, A. M.; Skrinsky, A. N.; Geer, S. et al.
Object Type: Article
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 97, No. 144, Ed. 1 Thursday, April 5, 2012 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 97, No. 144, Ed. 1 Thursday, April 5, 2012

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: April 5, 2012
Creator: Gibbs, Angenene
Object Type: Newspaper
System: The Gateway to Oklahoma History
Dynamic structure factor in warm dense beryllium (open access)

Dynamic structure factor in warm dense beryllium

None
Date: April 5, 2012
Creator: Glenzer, S H; Fortmann, C; Doeppner, T; Plagemann, K U; Sperling, P; Thiele, R et al.
Object Type: Article
System: The UNT Digital Library
Keene Star (Keene, Tex.), Vol. 19, No. 36, Ed. 1 Thursday, April 5, 2012 (open access)

Keene Star (Keene, Tex.), Vol. 19, No. 36, Ed. 1 Thursday, April 5, 2012

Weekly newspaper from Keene, Texas that includes local, state, and national news along with advertising.
Date: April 5, 2012
Creator: Gnadt, Paul
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 99, No. 43, Ed. 1 Thursday, April 5, 2012 (open access)

North Texas Daily (Denton, Tex.), Vol. 99, No. 43, Ed. 1 Thursday, April 5, 2012

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state, and campus news along with advertising.
Date: April 5, 2012
Creator: Gorman, Sean
Object Type: Newspaper
System: The Portal to Texas History
Dispute Settlement in the World Trade Organization (WTO): An Overview (open access)

Dispute Settlement in the World Trade Organization (WTO): An Overview

None
Date: April 5, 2012
Creator: Grimmett, Jeanne J.
Object Type: Report
System: The UNT Digital Library
Conceptual Design - Polar Drive Ignition Campaign (open access)

Conceptual Design - Polar Drive Ignition Campaign

The Laboratory for Laser Energetics (LLE) at the University of Rochester is proposing a collaborative effort with Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratories (LANL), the Naval Research Laboratory (NRL), and General Atomics (GA) with the goal of developing a cryogenic polar drive (PD) ignition platform on the National Ignition Facility (NIF). The scope of this proposed project requires close discourse among theorists, experimentalists, and laser and system engineers. This document describes how this proposed project can be broken into a series of parallel independent activities that, if implemented, could deliver this goal in the 2017 timeframe. This Conceptual Design document is arranged into two sections: mission need and design requirements. Design requirements are divided into four subsystems: (1) A point design that details the necessary target specifications and laser pulse requirements; (2) The beam smoothing subsystem that describes the MultiFM 1D smoothing by spectral dispersion (SSD); (3) New optical elements that include continuous phase plates (CPP's) and distributed polarization rotators (DPR's); and (4) The cryogenic target handling and insertion subsystem, which includes the design, fabrication, testing, and deployment of a dedicated PD ignition target insertion cryostat (PD-ITIC). This document includes appendices covering: the primary criteria and functional …
Date: April 5, 2012
Creator: Hansen, R
Object Type: Report
System: The UNT Digital Library
Oral History Interview with Rena Pederson, April 5, 2012 (open access)

Oral History Interview with Rena Pederson, April 5, 2012

Interview with Rena Pederson, a former journalist in Dallas, Texas. The interview includes biographical information about her life growing up, her educational background, her career with The Dallas Morning News and other newspapers, the books she has written, and her work in communications and public affairs.
Date: April 5, 2012
Creator: Harding, Anne; Dann, Lori & Pederson, Rena
Object Type: Text
System: The UNT Digital Library
Crowley Star (Crowley, Tex.), Vol. 25, No. 48, Ed. 1 Thursday, April 5, 2012 (open access)

Crowley Star (Crowley, Tex.), Vol. 25, No. 48, Ed. 1 Thursday, April 5, 2012

Weekly newspaper from Crowley, Texas that includes local, state, and national news along with advertising.
Date: April 5, 2012
Creator: Hinton, Jay
Object Type: Newspaper
System: The Portal to Texas History