Digital Commons Network^™

A Measurement Of The Q2, W And T Dependences Of Deeply Virtual Compton Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita Mattingly, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch, I. Brock, H. Hartmann

Faculty Publications

Deeply virtual Compton scattering, γ*p→γp has been measured in e+p collisions at HERA with the ZEUS detector using an integrated luminosity of 61.1 pb-1. Cross sections are presented as a function of the photon virtuality, Q2, and photon-proton centre-of-mass energy, W, for a wide region of the phase space, Q2 > 1.5GeV2 and 40 < W < 170GeV. A subsample of events in which the scattered proton is measured in the leading proton spectrometer, corresponding to an integrated luminosity of 31.3 pb-1, is used for the first direct measurement of the differential cross section as a function of t, where t is the square of the four-momentum transfer at the proton vertex. © SISSA 2009.

An Analysis Of The Impact Of Information Security Policies On Computer Security Breach Incidents In Law Firms, Faith M. Heikkila

CCAC Theses and Dissertations

Law firms maintain and store voluminous amounts of highly confidential and proprietary data, such as attorney-client privileged information, intellectual properties, financials, trade secrets, personal, and other sensitive information. There is an ethical obligation to protect law firm client data from unauthorized access. Security breaches jeopardize the reputation of the law firm and could have a substantial financial impact if these confidential data are compromised. Information security policies describe the security goals of a law firm and the acceptable actions and uses of law firm information resources.

In this dissertation investigation, the author examined the problem of whether information security policies …

Everyone Is A Curator: Human-Assisted Preservation For Ore Aggregations, Frank Mccown, Michael L. Nelson, Herbert Van De Sompel

Computer Science Faculty Publications

The Open Archives Initiative (OAI) has recently created the Object Reuse and Exchange (ORE) project that defines Resource Maps (ReMs) for describing aggregations of web resources. These aggregations are susceptible to many of the same preservation challenges that face other web resources. In this paper, we investigate how the aggregations of web resources can be preserved outside of the typical repository environment and instead rely on the thousands of interactive users in the web community and the Web Infrastructure (the collection of web archives, search engines, and personal archiving services) to facilitate preservation. Inspired by Web 2.0 services such as …

Correlation Of Music Charts And Search Engine Rankings, Martin Klein, Olena Hunsicker, Michael Nelson

Computer Science Faculty Publications

We investigate the question whether expert rankings of real-world entities correlate with search engine (SE) rankings of corresponding web resources. We compare Billboards "Hot 100 Airplay" music charts with SE rankings of associated web resources. Out of nine comparisons we found two strong, two moderate, two weak and one negative correlation. The remaining two comparisons were inconclusive.

Object Reuse And Exchange, Michael L. Nelson, Carl Lagoze, Herbert Van De Sompel, Pete Johnston, Robert Sanderson, Simeon Warner, Jürgen Sieck (Ed.), Michael A. Herzog (Ed.)

Computer Science Faculty Publications

The Open Archives Object Reuse and Exchange (OAI-ORE) project defines standards for the description and exchange of aggregations of Web resources. The OAI-ORE abstract data model is conformant with the Architecture of the World Wide Web and leverages concepts from the Semantic Web, including RDF descriptions and Linked Data. In this paper we provide a brief review of a motivating example and its serialization in Atom.

Multicast Encryption Infrastructure For Security In Sensor Networks, Richard R. Brooks, Brijesh Pillai, Matthew Pirretti, Michele C. Weigle

Computer Science Faculty Publications

Designing secure sensor networks is difficult. We propose an approach that uses multicast communications and requires fewer encryptions than pairwise communications. The network is partitioned into multicast regions; each region is managed by a sensor node chosen to act as a keyserver. The keyservers solicit nodes in their neighborhood to join the local multicast tree. The keyserver generates a binary tree of keys to maintain communication within the multicast region using a shared key. Our approach supports a distributed key agreement protocol that identifies the compromised keys and supports membership changes with minimum system overhead. We evaluate the overhead of …

Evaluating Multicore Algorithms On The Unified Memory Model, John E. Savage, Mohammad Zubair

Computer Science Faculty Publications

One of the challenges to achieving good performance on multicore architectures is the effective utilization of the underlying memory hierarchy. While this is an issue for single-core architectures, it is a critical problem for multicore chips. In this paper, we formulate the unified multicore model (UMM) to help understand the fundamental limits on cache performance on these architectures. The UMM seamlessly handles different types of multiple-core processors with varying degrees of cache sharing at different levels. We demonstrate that our model can be used to study a variety of multicore architectures on a variety of applications. In particular, we use …

Satellite Outreach Services Program To Under-Represented Students: "Being In Their Space, Not On Myspace", Kathleen Keating, Paulita Aguilar

University Libraries & Learning Sciences Faculty and Staff Publications

strategic goal of the University of New Mexico is student retention, especially for underrepresented students. To assist in reaching that goal, the University Libraries offered the Satellite Outreach Services Program, which included reference and instruction, and was provided in the university's multicultural student services centers. This article describes the program's planning, implementation, and statistics and includes a detailed description of outreach activities for one of the student centers, American Indian Student Services.

Measurement Of Trilinear Gauge Boson Couplings From Ww + Wz → Lvjj Events In Pp Collisions At √S= 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Kenneth Bloom Publications

We present a direct measurement of trilinear gauge boson couplings at γWW and ZWW vertices in WW and WZ events produced in pp collisions at √s= 1.96 TeV. We consider events with one electron or muon, missing transverse energy, and at least two jets. The data were collected using the D0 detector and correspond to 1.1 fb^-1 of integrated luminosity. Considering two different relations between the couplings at the γWW and ZWW vertices, we measure these couplings at 68% C.L. to be κ_γ = 1.07^+0.26_-0.29, λ = 0.00_-0.06^+0.06, …

Measurement Of The Top Quark Mass In Final States With Two Leptons, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Kenneth Bloom Publications

We present measurements of the top quark mass (m_t) in tt candidate events with two final state leptons using 1 fb^-1 of data collected by the D0 experiment. Our data sample is selected by requiring two fully identified leptons or by relaxing one lepton requirement to an isolated track if at least one jet is tagged as a b jet. The top quark mass is extracted after reconstructing the event kinematics under the tt hypothesis using two methods. In the first method, we integrate over expected neutrino rapidity distributions, and in the second we calculate a …

Search For Charged Higgs Bosons Decaying Into Top And Bottom Quarks In Pp Collisions, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We describe a search for production of a charged Higgs boson, qq’ → H⁺, reconstructed in the tb final state in the mass range 180 ≤ M_H⁺ ≤ 300 GeV. The search was undertaken at the Fermilab Tevatron collider with a center-of-mass energy √s =1.96 TeV and uses 0.9 fb^-1 of data collected with the D0 detector. We find no evidence for charged Higgs boson production and set upper limits on the production cross section in the types I, II, and III two-Higgs-doublet models (2HDMs). An excluded region in the (M_{H^{+ …}}

Measurement Of Γ + B + X And Γ + C +X Production Cross Sections In Pp Collisions At √S = 1.96tev, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

First measurements of the differential cross sections d³σ/(d p_T^γ dy^γ dy^jet) for the inclusive production of a photon in association with a heavy quark (b, c) jet are presented, covering photon transverse momenta 30 < p_T^γ < 150 GeV, photon rapidities |y^γ| < 1.0, jet rapidities |y^jet| < 0.8, and jet transverse momenta p_T^jet > 15 GeV. The results are based on an integrated luminosity of 1 fb^-1 in pp collisions at √s = 1.96 TeV recorded with the D0 detector at the Fermilab Tevatron Collider. The results are compared with next-to-leading order perturbative QCD predictions.

Evidence Of Ww And Wz Production With Lepton + Jets Final States In Pp Collisions At √S = 1.96 Tev, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Kenneth Bloom Publications

We present first evidence for WW + WZ production in lepton + jets final states at a hadron collider. The data correspond to 1.07 fb^-1 of integrated luminosity collected with the D0 detector at the Fermilab Tevatron in pp collisions at √s = 1.96 TeV. The observed cross section for WW + WZ production is 20.2 ± 4.5 pb, consistent with the standard model and more precise than previous measurements in fully leptonic final states. The probability that background fluctuations alone produce this excess is 10^-6, which corresponds to a significance of 4.4 standard deviations.

Direct Measurement Of The W Boson Width, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W → ev candidate events. Data from approximately 1 fb^-1 of integrated luminosity recorded at √s = 1.96 TeV by the D0 detector at the Fermilab Tevatron pp collider are analyzed. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 ± 0.072 GeV, is in …

Search For Resonant Diphoton Production With The D0 Detector, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We present a search for a narrow resonance in the inclusive diphoton final state using ~2.7 fb^-1 of data collected with the D0 detector at the Fermilab Tevatron pp Collider.We observe good agreement between the data and the background prediction, and set the first 95% C.L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.

Search For Dark Photons From Supersymmetric Hidden Valleys, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We search for a new light gauge boson, a dark photon, with the D0 experiment. In the model we consider, supersymmetric partners are pair produced and cascade to the lightest neutralinos that can decay into the hidden sector state plus either a photon or a dark photon. The dark photon decays through its mixing with a photon into fermion pairs. We therefore investigate a previously unexplored final state that contains a photon, two spatially close leptons, and large missing transverse energy.We do not observe any evidence for dark photons and set a limit on their production.

Electron Attachment To Trans-Azobenzene, Alberto Modelli, Paul Burrow

Paul Burrow Publications

The temporary anion states of gas-phase trans-azobenzene are characterized by means of electron transmission spectroscopy (ETS) in the 0–6 eV range. The measured energies of vertical electron attachment are compared with the energies of the π* virtual orbitals of the neutral molecule supplied by HF (at MP2 optimized geometries) and B3LYP calculations. The calculated energies, scaled with empirical equations, reproduce quantitatively the energies of the corresponding spectral features and predict a positive vertical electron affinity of 0.83 eV.

The total anion current at the walls of the collision chamber and the mass-selected molecular anion current are also reported as …

Feynman’S Relativistic Electrodynamics Paradox And The Aharonov-Bohm Effect, Adam Caprez, Herman Batelaan

Department of Physics and Astronomy: Faculty Publications

An analysis is done of a relativistic paradox posed in the Feynman Lectures of Physics involving two interacting charges. The physical system presented is compared with similar systems that also lead to relativistic paradoxes. The momentum conservation problem for these systems is presented. The relation between the presented analysis and the ongoing debates on momentum conservation in the Aharonov-Bohm problem is discussed.

Magnetic Correlations In Nanocomposite Fept:Au And Fept:C Films, Thomas A. George, Ralph Skomski, David J. Sellmyer

Ralph Skomski Publications

The nanostructure and magnetism of L1₀-ordered FePt crystallites in matrices of Au and C are investigated as a function of the Au and C contents. Emphasis is on the relation between hysteresis-loop shape, magnetic correlation length, and structural disorder, as relevant to magnetic recording media. The highly (001) textured thin films are produced by annealing [Fe&#;&#;Pt&#;X]_n multilayers. The coercivity and the hysteresis-loop slope at coercivity increase and decrease, respectively, with increasing volume fraction of the matrix. The magnetic force microscopy images show that the slope decrease is accompanied by a reduction in the magnetic correlation length. These …

Ncuwm Talk Abstracts 2009

Nebraska Conference for Undergraduate Women in Mathematics

No abstract provided.

Ncuwm Poster Abstracts 2009

Nebraska Conference for Undergraduate Women in Mathematics

No abstract provided.

The Auslander-Bridger Formula And The Gorenstein Property For Coherent Rings, Livia Hummel, Thomas Marley

Department of Mathematics: Faculty Publications

The concept of Gorenstein dimension, defined by Auslander and Bridger for finitely generated modules over a Noetherian ring, is studied in the context of finitely presented modules over a coherent ring. A generalization of the Auslander-Bridger formula is established and is used as a cornerstone in the development of a theory of coherent Gorenstein rings.

Nebraska Cooperative Fish And Wildlife Research Unit—Usgs: Report Of Activities October 2008 – October 2009

Nebraska Cooperative Fish and Wildlife Research Unit: Annual Reports

CONTENTS
INTRODUCTION .. 1
PERSONNEL AND COOPERATORS . 2
Unit Personnel .. 2
Coordinating Committee Members . 4
Cooperators .. 5
MILESTONES .. 7
AWARDS AND RECOGNITIONS .. 8
THESES AND DISERTATIONS .. 8
PROJECTS IN FISHERY SCIENCE . 9
Angler Behavior in Response to Management Actions on Nebraska Reservoirs . 10
Geographic Trends in Contamination of Nebraska’s Surface Waters as Indexed by Sex Steroids of Common Carp .. 11
Impact of White Perch on Walleye at Branched Oak and Pawnee Reservoirs . 12
Latitudinal Influence on Age Estimation of Bluegill . 13
Predators of White Perch at Branched Oak …

The Communicator, Volume 5, Issue 1, January 2009

The Communicator: News from the Nebraska Cooperative Fish and Wildlife Research Unit

Faces – New and Old (Cassie Manhart; Peter Spirk; Nate Gosch; Beth Forbus) Changes (Dustin Martin; Chris Lewis; Thad Miller; Justin Williams) New Federal Staff (Dr. Joseph (TJ) Fontaine) Publications New Research Angler Behavior in Response to Management Actions on Nebraska Reservoirs Missouri River Mitigation: Implementation of Amphibian Monitoring and Adaptive Management for Wetland Restoration Evaluation Current Research Assessing the Relationship between Stable Isotopes and Grassland Bird Productivity on Great Plains National Park Service Properties Cross-Scale Structure in Ecosystems Diversity and Ecological Functions Conferences/Meetings/Workshops Teaching Awards & Recognitions UCARE Project Graduate Student News (Aaron Alai; Aaron Lotz; Ryan Lueckenhoff; Annabel …

The Communicator, Volume 5, Issue 2, August 2009

The Communicator: News from the Nebraska Cooperative Fish and Wildlife Research Unit

Faces – New and Old (Tony Barada; Jason DeBoer; Caryl Cashmere; Karie Decker; Lucas Kowaleski; Kody Unstad; Michelle Hellman; Carla Knight; Lexi Maple; Thad Miller) Awards & Recognitions (Jason DeBoer; Andrew Furman; Dustin Martin; Kristine Nemec; Sarah Rehme; Amy Williams) Service (Kevin Pope; Valerie Egger) Current Research Angler Behavior in Response to Management Actions on Nebraska Reservoirs Assessing the Relationship between Stable Isotopes and Grassland Bird Productivity on Great Plains National Park Service Properties Diversity and Ecological Functions The Effect of Common Reed (Phragmites australis) on River Otter (Lontra canadensis) Habitat Use Identifying Socio-Ecological Factors Determining Invasions and Extinctions Conferences/Meetings/Workshops …

Variability In Population Abundance Is Associated With Thresholds Between Scaling Regimes, Donald Wardwell, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Discontinuous structure in landscapes may result in discontinuous, aggregated species bodymass patterns, reflecting the scales of structure available to animal communities within a landscape. The edges of these body-mass aggregations reflect transitions between available scales of landscape structure. Such transitions, or scale breaks, are theoretically associated with increased biological variability. We hypothesized that variability in population abundance is greater in animal species near the edge of bodymass aggregations than it is in species that are situated in the interior of body-mass aggregations. We tested this hypothesis by examining both temporal and spatial variability in the abundance of species in the …

A Neotropical Migrant Bird’S Dilemma— Where To Stop For A Good Meal, Joseph J. Fontaine, Charles Van Riper Iii

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

To learn how migrating birds determine where to stop and find food, scientists from the U.S. Geological Survey, Northern Arizona University, and The University of Arizona studied the behavior of 28 species of neotropical migrant songbirds—warblers, flycatchers, tanagers, and vireos—along the lower Colorado River from 2001 to 2004. They found that, like interstate travelers greeted by restaurant billboards, songbirds flying over Cibola National Wildlife Refuge, Arizona, relied on the flowering of honey mesquite (Prosopis glandulosa) to detect the availability of insects that they prey on. Understanding where and why migrant birds stop will help land managers better protect …

Spatial And Temporal Variation In Climate Change: A Bird’S Eye View, Joseph J. Fontaine, K. L. Decker, S. K. Skagen, C. Van Riper Iii

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recent changes in global climate have dramatically altered worldwide temperatures and the corresponding timing of seasonal climate conditions. Recognizing the degree to which species respond to changing climates is therefore an area of increasing conservation concern as species that are unable to respond face increased risk of extinction. Here we examine spatial and temporal heterogeneity in the rate of climate change across western North America and discuss the potential for conditions to arise that may limit the ability of western migratory birds to adapt to changing climates. Based on 52 years of climate data, we show that changes in temperature …

Stomach Capacities Of Six Freshwater Fishes, Nathan J.C. Gosch, Kevin L. Pope, Paul H. Michaletz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We investigated the relationship between stomach capacity and total body length in bluegill (Lepomis macrocirirus), spotted bass (Microplerus punctulatus), white crappie (Pomoxis annularis), black crappie (Pomoxis nigromoculatus), channel catfish (Ictalurus punctatus) , and white bass (Morone chrysops). The rate of change in stomach capacity for a given change in fish length was greatest for spoiled bass and channel catfish, which may indicate greater ontogenetic shifts in feeding strategies. Fish with larger stomach capacities should have more plastic diets because they are capable of consuming a wider range of …

Asian Carp In The Missouri River: Analysis From Multiple Missouri River Habitat And Fisheries Programs, Greg A. Wanner, Robert A. Klumb

National Invasive Species Council

Bighead carp Hypophthalmichthys nobilis, silver carp H. molitrix, black carp Mylopharyngodon piceus, and grass carp Ctenopharyngodon idella, collectively referred to as Asian carps, are invasive species that were either accidentally or intentionally introduced into the Mississippi River basin. The expansion of Asian carp into the Missouri River is not well understood and knowledge of population characteristics within this river were lacking. The objectives of this study were to describe the relative abundance, size structure, and spatial and temporal trends of Asian carp using multiple gears from three long-term fish community monitoring programs in the Missouri River …