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Large Synoptic Survey Telescope: From Science Drivers to Reference Design

Description: In the history of astronomy, major advances in our understanding of the Universe have come from dramatic improvements in our ability to accurately measure astronomical quantities. Aided by rapid progress in information technology, current sky surveys are changing the way we view and study the Universe. Next-generation surveys will maintain this revolutionary progress. We focus here on the most ambitious survey currently planned in the visible band, the Large Synoptic Survey Telescope (LSST). LS… more
Date: October 14, 2011
Creator: Ivezic, Z.; Axelrod, T.; Brandt, W. N.; Burke, D. L.; Claver, C. F.; Connolly, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems

Description: Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. The Baryon Oscillation Spectroscopic Survey (BOSS) will measure redshifts of 1.5 million massive galaxies and Ly{alpha} forest spectra of 150,000 quasars, using the baryon acoustic oscillation (BAO) feature… more
Date: January 1, 2011
Creator: Eisenstein, Daniel J.; Weinberg, David H.; Agol, Eric; Aihara, Hiroaki; Prieto, Carlos Allende; Anderson, Scott F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Lab-Based Measurement of Remediation Techniques for Radiation Portal Monitors (Initial Report)

Description: Radiation Portal Monitors (RPM) deployed by the Second Line of Defense (SLD) are known to be sensitive to the natural environmental radioactive background. There are several techniques used to mitigate the effects of background on the monitors, but since the installation environments can vary significantly from one another the need for a standardized, systematic, study of remediation techniques was proposed and carried out. This study is not meant to serve as the absolute last word on the subje… more
Date: February 1, 2012
Creator: Livesay, Jake; Guzzardo, Tyler & Lousteau, Angela L
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New Prospects in High Energy Astrophysics

Description: Recent discoveries using TeV, X-ray and radio telescopes as well as Ultra High Energy Cosmic Ray arrays are leading to new insights into longstanding puzzles in high energy astrophysics. Many of these insights come from combining observations throughout the electromagnetic and other spectra as well as evidence assembled from different types of source to propose general principles. Issues discussed in this general overview include methods of accelerating relativistic particles, and amplifying ma… more
Date: November 15, 2011
Creator: Blandford, Roger
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Physics validation studies for muon collider detector background simulations

Description: Within the broad discipline of physics, the study of the fundamental forces of nature and the most basic constituents of the universe belongs to the field of particle physics. While frequently referred to as 'high-energy physics,' or by the acronym 'HEP,' particle physics is not driven just by the quest for ever-greater energies in particle accelerators. Rather, particle physics is seen as having three distinct areas of focus: the cosmic, intensity, and energy frontiers. These three frontiers a… more
Date: July 1, 2011
Creator: Morris, Aaron Owen
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Connection between Galaxies and Dark Matter Structures in the Local Universe

Description: We provide new constraints on the connection between galaxies in the local Universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the {Lambda}CDM model using WMAP7 cosmological parameters. Predictions for the abundance and clustering properties of dark matter halos, and the relationship between dark matter hosts and substructures, are based on a high-resolution cosmological simulation, the Bolshoi simulation. We associate galaxi… more
Date: July 11, 2012
Creator: Reddick, Rachel M.; Wechsler, Risa H.; Tinker, Jeremy L. & Behroozi, Peter S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transient evolution of a photon gas in the nonlinear QED vacuum

Description: Thermally induced vacuum polarization stemming from QED radiative corrections to the electromagnetic field equations is studied. The physical behavior of thermal radiation, in the nonlinear QED vacuum first described by Heisenberg and Euler, is a problem of some theoretical importance in view of its relation to the cosmic microwave background (CMB), early universe evolution, and Hawking-Unruh radiation. The questions of evolution toward equilibrium, stability, and invariance of thermal radiatio… more
Date: October 4, 2011
Creator: Wu, S Q & Hartemann, F V
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The BigBoss Experiment

Description: BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra o… more
Date: June 7, 2012
Creator: Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complete Calculation of Evaluated Maxwellian-Averaged Cross Sections and Their Uncertainties for S-Process Nucleosynthesis

Description: Present contribution represents a significant improvement of our previous calculation of Maxwellian-averaged cross sections and astrophysical reaction rates. Addition of newly-evaluated neutron reaction libraries, such as ROSFOND and Low-Fidelity Covariance Project, and improvements in data processing techniques allowed us to extend it for entire range of sprocess nuclei, calculate Maxwellian-averaged cross section uncertainties for the first time, and provide additional insights on all current… more
Date: July 19, 2010
Creator: Pritychenko, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scattering Amplitudes: The Most Perfect Microscopic Structures in the Universe

Description: This article gives an overview of many of the recent developments in understanding the structure of relativistic scattering amplitudes in gauge theories ranging from QCD to N = 4 super-Yang-Mills theory, as well as (super)gravity. I also provide a pedagogical introduction to some of the basic tools used to organize and illuminate the color and kinematic structure of amplitudes. This article is an invited review introducing a special issue of Journal of Physics A devoted to 'Scattering Amplitude… more
Date: November 4, 2011
Creator: Dixon, Lance J. & /SLAC, /CERN
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Searches for Fourth Generation Fermions

Description: We present the results from searches for fourth generation fermions performed using data samples collected by the CDF II and D0 Detectors at the Fermilab Tevatron p{bar p} collider. Many of these results represent the most stringent 95% C. L. limits on masses of new fermions to-date. A fourth chiral generation of massive fermions with the same quantum numbers as the known fermions is one of the simplest extensions of the SM with three generations. The fourth generation is predicted in a number … more
Date: September 1, 2011
Creator: Ivanov, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Potentially Missing Physics of the Early Universe: Nonlinear Vacuum Polarization in Intense Blackbody Radiation

Description: The standard Big Bang universe model is mainly based on linear interactions, except during exotic periods such as inflation. The purpose of the present proposal is to explore the effects, if any, of vacuum polarization in the very high energy density environment of the early universe. These conditions can be found today in astrophysical settings and may also be emulated in the laboratory using high intensity advanced lasers. Shortly after the Big Bang, there once existed a time when the energy … more
Date: April 13, 2010
Creator: Wu, S Q & Hartemann, F V
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutrino Oscillation Physics

Description: To complement the neutrino-physics lectures given at the 2011 International School on Astro Particle Physics devoted to Neutrino Physics and Astrophysics (ISAPP 2011; Varenna, Italy), at the 2011 European School of High Energy Physics (ESHEP 2011; Cheila Gradistei, Romania), and, in modified form, at other summer schools, we present here a written description of the physics of neutrino oscillation. This description is centered on a new way of deriving the oscillation probability. We also provid… more
Date: June 1, 2012
Creator: Kayser, Boris
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A New Neutrino Oscillation

Description: Starting in the late 1960s, neutrino detectors began to see signs that neutrinos, now known to come in the flavors electron ({nu}{sub e}), muon ({nu}{sub {mu}}), and tau ({nu}{sub {tau}}), could transform from one flavor to another. The findings implied that neutrinos must have mass, since massless particles travel at the speed of light and their clocks, so to speak, don't tick, thus they cannot change. What has since been discovered is that neutrinos oscillate at two distinct scales, 500 km/Ge… more
Date: July 1, 2011
Creator: Parke, Stephen J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Siting the International Linear Collider at Hanford

Description: Review of the proposed International Linear Collider, applications in high energy physics, and evaluation of the Hanford Site as a possible location for siting the facilityl.
Date: March 15, 2012
Creator: Kouzes, Richard T.; Asner, David M.; Brodzinski, Ronald L.; Fast, James E. & Miley, Harry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MiniBooNE "Windows on the Universe"

Description: Progress in the last few decades has left neutrino physics with several vexing issues. Among them are the following questions: (1) Why are lepton mixing angles so different from those in the quark sector? (2) What is the most probable range of the reactor mixing angle? (3) Is the atmospheric mixing angle maximal? (4) What is the number of fermion generations? These are some of the issues that neutrino science hopes to study; this article will explore these questions as part of a more general sc… more
Date: December 9, 2010
Creator: Stefanski, Ray
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Mass Distribution and Assembly of the Milky Way from the Properties of the Magellanic Clouds

Description: We present a new measurement of the mass of the Milky Way (MW) based on observed properties of its largest satellite galaxies, the Magellanic Clouds (MCs), and an assumed prior of a {Lambda}CDM universe. The large, high-resolution Bolshoi cosmological simulation of this universe provides a means to statistically sample the dynamical properties of bright satellite galaxies in a large population of dark matter halos. The observed properties of the MCs, including their circular velocity, distance … more
Date: February 29, 2012
Creator: Busha, Michael T.; Marshall, Philip J.; Wechsler, Risa H.; Klypin, Anatoly & Primack, Joel
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Brief 67 Health Physics Enrollments and Degrees Survey, 2009 Data

Description: This survey includes degrees granted between September 1, 2008 and August 31, 2009. Enrollment information refers to the fall term 2009. Twenty-four academic programs were included in the survey universe, and all twenty-four responded. The report includes data by degree level including citizenship, gender, and race/ethnicity, plus enrollments of junior and senior undergraduate students and graduate students.
Date: March 1, 2010
Creator: Blair, Larry M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Report on INL Activities for Uncertainty Reduction Analysis of FY11

Description: This report presents the status of activities performed at INL under the ARC Work Package on 'Uncertainty Reduction Analyses' that has a main goal the reduction of uncertainties associated with nuclear data on neutronic integral parameters of interest for the design of advanced fast reactors under consideration by the ARC program. First, an analysis of experiments was carried out. For both JOYO (the first Japanese fast reactor) and ZPPR-9 (a large size zero power plutonium fueled experiment per… more
Date: September 1, 2011
Creator: Plamiotti, G.; Hiruta, H. & Salvatores, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quantum Vacuum Structure and Cosmology

Description: Contemporary physics faces three great riddles that lie at the intersection of quantum theory, particle physics and cosmology. They are: (1) The expansion of the universe is accelerating - an extra factor of two appears in the size; (2) Zero-point fluctuations do not gravitate - a matter of 120 orders of magnitude; and (3) The 'True' quantum vacuum state does not gravitate. The latter two are explicitly problems related to the interpretation and the physical role and relation of the quantum vac… more
Date: December 5, 2011
Creator: Rafelski, Johann; Labun, Lance; Hadad, Yaron; U., /Arizona U. /Munich; Chen, Pisin & /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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LIPSS Free-Electron Laser Searches for Dark Matter

Description: A variety of Dark Matter particle candidates have been hypothesized by physics Beyond the Standard Model (BSM) in the very light (10{sup -6} - 10{sup -3} eV) range. In the past decade several international groups have conducted laboratory experiments designed to either produce such particles or extend the boundaries in parameter space. The LIght Pseudo-scalar and Scalar Search (LIPSS) Collaboration, using the 'Light Shining through a Wall' (LSW) technique, passes the high average powe… more
Date: September 1, 2011
Creator: Afanaciev, Andrei; Beard, Kevin; Biallas, George; Boyce, James R; Minarni, M; Ramdon, R et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fast Generation of Ensembles of Cosmological N-Body Simulations via Mode-Resampling

Description: We present an algorithm for quickly generating multiple realizations of N-body simulations to be used, for example, for cosmological parameter estimation from surveys of large-scale structure. Our algorithm uses a new method to resample the large-scale (Gaussian-distributed) Fourier modes in a periodic N-body simulation box in a manner that properly accounts for the nonlinear mode-coupling between large and small scales. We find that our method for adding new large-scale mode realizations recov… more
Date: February 14, 2011
Creator: Schneider, M D; Cole, S; Frenk, C S & Szapudi, I
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The fate of high redshift massive compact galaxies in dense environments

Description: Massive compact galaxies seem to be more common at high redshift than in the local universe, especially in denser environments. To investigate the fate of such massive galaxies identified at z {approx} 2 we analyse the evolution of their properties in three cosmological hydrodynamical simulations that form virialized galaxy groups of mass {approx} 10{sup 13} M{sub {circle_dot}} hosting a central massive elliptical/S0 galaxy by redshift zero. We find that at redshift {approx} 2 the population of… more
Date: January 1, 2012
Creator: Kaufmann, Tobias; Mayer, Lucio; Carollo, Marcella & Feldmann, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory

Description: Observations of cosmic ray arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic r… more
Date: January 1, 2012
Creator: Abreu, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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