The status of open heavy flavor production at RHIC (open access)

The status of open heavy flavor production at RHIC

We discuss the calculation of open heavy flavor cross sections at RHIC and describe how the semileptonic decays of charm and bottom quarks can be separated.
Date: December 21, 2010
Creator: Vogt, R
System: The UNT Digital Library
Gravitationally Consistent HALO Catalogs and Merger Trees for Precision Cosmology (open access)

Gravitationally Consistent HALO Catalogs and Merger Trees for Precision Cosmology

Presents a new algorithm for generating merger trees and halo catologs.
Date: December 21, 2012
Creator: Behroozi, Peter S.; Wechsler, Risa H.; Wu, Hao-Yi; Busha, Michael T.; Klypin, Anatoly A. & Primack, Joel R.
System: The UNT Digital Library
Direct observation of imprinted antiferromagnetic vortex state in CoO/Fe/Ag(001) disks (open access)

Direct observation of imprinted antiferromagnetic vortex state in CoO/Fe/Ag(001) disks

In magnetic thin films, a magnetic vortex is a state in which the magnetization vector curls around the center of a confined structure. A vortex state in a thin film disk, for example, is a topological object characterized by the vortex polarity and the winding number. In ferromagnetic (FM) disks, these parameters govern many fundamental properties of the vortex such as its gyroscopic rotation, polarity reversal, core motion, and vortex pair excitation. However, in antiferromagnetic (AFM) disks, though there has been indirect evidence of the vortex state through observations of the induced FM-ordered spins in the AFM disk, they have never been observed directly in experiment. By fabricating single crystalline NiO/Fe/Ag(001) and CoO/Fe/Ag(001) disks and using X-ray Magnetic Linear Dichroism (XMLD), we show direct observation of the vortex state in an AFM disk of AFM/FM bilayer system. We observe that there are two types of AFM vortices, one of which has no analog in FM structures. Finally, we show that a frozen AFM vortex can bias a FM vortex at low temperature.
Date: December 21, 2010
Creator: Wu, J.; Carlton, D.; Park, J. S.; Meng, Y.; Arenholz, E.; Doran, A. et al.
System: The UNT Digital Library
Advantages of a soft protective layer for good signal-to-noise ratio proton radiographs in high debris environments (open access)

Advantages of a soft protective layer for good signal-to-noise ratio proton radiographs in high debris environments

None
Date: December 21, 2010
Creator: Le Galloudec, N. R.; Cobble, J.; Nelson, S. L.; Merwin, A.; Paudel, Y.; Shrestha, I. et al.
System: The UNT Digital Library
Quarkonia as a multi-purpose tool (open access)

Quarkonia as a multi-purpose tool

Quarkonia can be a very useful tool for understanding the medium in which they are produced and pass through. However, their usefulness as a tool depends on how well certain aspects of their behavior in cold matter are understood.
Date: December 21, 2010
Creator: Vogt, R
System: The UNT Digital Library
Developing extensible lattice-Boltzmann simulators for general-purpose graphics-processing units (open access)

Developing extensible lattice-Boltzmann simulators for general-purpose graphics-processing units

Lattice-Boltzmann methods are versatile numerical modeling techniques capable of reproducing a wide variety of fluid-mechanical behavior. These methods are well suited to parallel implementation, particularly on the single-instruction multiple data (SIMD) parallel processing environments found in computer graphics processing units (GPUs). Although more recent programming tools dramatically improve the ease with which GPU programs can be written, the programming environment still lacks the flexibility available to more traditional CPU programs. In particular, it may be difficult to develop modular and extensible programs that require variable on-device functionality with current GPU architectures. This paper describes a process of automatic code generation that overcomes these difficulties for lattice-Boltzmann simulations. It details the development of GPU-based modules for an extensible lattice-Boltzmann simulation package - LBHydra. The performance of the automatically generated code is compared to equivalent purpose written codes for both single-phase, multiple-phase, and multiple-component flows. The flexibility of the new method is demonstrated by simulating a rising, dissolving droplet in a porous medium with user generated lattice-Boltzmann models and subroutines.
Date: December 21, 2011
Creator: Walsh, S C & Saar, M O
System: The UNT Digital Library
The Rockstar Phase-Space Temporal HALO Finder and the Velocity Offsets of Cluster Cores (open access)

The Rockstar Phase-Space Temporal HALO Finder and the Velocity Offsets of Cluster Cores

Presents a new algorithm for identifying dark matter halos, substructure, and tidal features.
Date: December 21, 2012
Creator: Behroozi, Peter S.; Wechsler, Risa H. & Wu, Hao-Yi
System: The UNT Digital Library
CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS (open access)

CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS

High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 134,137}Cs, {sup 90}Sr, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. An inorganic sorbent, monosodium titanate (MST), is currently used to remove {sup 90}Sr and alpha-emitting radionuclides, while a caustic-side solvent extraction process is used for removing {sup 134,137}Cs. A new peroxotitanate material, modified MST, or mMST, has recently been developed and has shown increased removal kinetics and capacity for {sup 90}Sr and alpha-emitting radionuclides compared to the current baseline material, MST. This paper describes recent results focused on further characterization of this material.
Date: December 21, 2010
Creator: Hobbs, D.; Taylor-Pashow, K. & Missimer, D.
System: The UNT Digital Library
Sheet Beam Klystron for the Navy FEL (open access)

Sheet Beam Klystron for the Navy FEL

None
Date: December 21, 2012
Creator: Jensen, Aaron; Fazio, Michael; Haase, Andy; Jongewaard, Erik; Martin, David; Neilson, Jeff et al.
System: The UNT Digital Library
Averages of B-Hadron, C-Hadron, and Tau-Lepton Properties as of Early 2012 (open access)

Averages of B-Hadron, C-Hadron, and Tau-Lepton Properties as of Early 2012

This report talks about Averages of B-Hadron, C-Hadron, and Tau-Lepton Properties as of Early 2012
Date: December 21, 2012
Creator: Amhis, Y.; /LPHE, Lausanne; Banerjee, Sw.; U., /Victoria; Bernhard, R.; U., /Freiburg et al.
System: The UNT Digital Library