Inverse-kinematics one-neutron pickup with fast rare-isotope beams

New measurements and reaction model calculations are reported for single neutron pickup reactions onto a fast \nuc{22}{Mg} secondary beam at 84 MeV per nucleon. Measurements were made on both carbon and beryllium targets, having very different structures, allowing a first investigation of the likely nature of the pickup reaction mechanism. The measurements involve thick reaction targets and $\gamma$-ray spectroscopy of the projectile-like reaction residue for final-state resolution, that permit experiments with low incident beam rates compared to traditional low-energy transfer reactions. From measured longitudinal momentum distributions we show that the \nuc{12}{C} (\nuc{22}{Mg},\nuc{23}{Mg}+\gamma)X reaction largely proceeds as a direct two-body reaction, the neutron transfer producing bound \nuc{11}{C} target residues. The corresponding reaction on the \nuc{9}{Be} target seems to largely leave the \nuc{8}{Be} residual nucleus unbound at excitation energies high in the continuum. We discuss the possible use of such fast-beam one-neutron pickup reactions to track single-particle strength in exotic nuclei, and also their expected sensitivity to neutron high-$\ell$ (intruder) states which are often direct indicators of shell evolution and the disappearance of magic numbers in the exotic regime.Comment: 8 pages, 5 figure

In-beam gamma-ray spectroscopy of 35Mg and 33Na

Excited states in the very neutron-rich nuclei 35Mg and 33Na were populated in the fragmentation of a 38Si projectile beam on a Be target at 83 MeV/u beam energy. We report on the first observation of gamma-ray transitions in 35Mg, the odd-N neighbor of 34Mg and 36Mg, which are known to be part of the "Island of Inversion" around N = 20. The results are discussed in the framework of large- scale shell-model calculations. For the A = 3Z nucleus 33Na, a new gamma-ray transition was observed that is suggested to complete the gamma-ray cascade 7/2+ --> 5/2+ --> 3/2+ gs connecting three neutron 2p-2h intruder states that are predicted to form a close-to-ideal K = 3/2 rotational band in the strong-coupling limit.Comment: Accepted for publication Phys. Rev. C. March 16, 2011: Replaced figures 3 and 5. We thank Alfredo Poves for pointing out a problem with the two figure

Panel. Community Engagement and Interpreting Slavery in North Mississippi

The “Behind the Big House” Project / Jodi Skipper, University of Mississippi and Suzanne DavidsonBehind the Big House is a slave dwelling interpretation program in Holly Springs, Mississippi. The program offers a counter-narrative to the Holly Springs Annual Pilgrimage Tour of Historic Homes and Churches, the city’s main tourist attraction which has historically neglected the contributions of enslaved persons. Behind the Big House was initiated by several private property owners who understood that interpreting the structures which housed enslaved persons could help to remedy such omissions. In addition to discussing how historical memory impacts the functions of these sites in the present, Skipper will discuss her role as a Behind the Big House tour guide, and how she incorporates the tour as an applied component in her courses. Slavery and Its Descendants / W. Ralph Eubanks, University of MississippiThe legacy of slavery and its impact across generations of African Americans is often ignored or overlooked, particularly by institutions that benefited from enslaved labor. The University of Mississippi is no exception. Payment records from the 1840s in the archives of the University of Mississippi indicate that Robert Sheegog—who once owned Faulkner’s home Rowan Oak—along with other local slave owners, loaned slaves to the University. This connection between the slaves of Rowan Oak and the building of the University of Mississippi holds the potential to redefine the idea of legacy connections to the University, since inevitably the descendants of several of those slaves are among the university’s alumni. This paper will discuss the on-going work of the University of Mississippi’s slavery research group and the possible outcomes of planned genealogical research to find the descendants of the slaves from Faulkner’s Rowan Oak who built the university.The University of Mississippi Slavery Research Group / Jeffrey Jackson and Charles K. Ross, University of MississippiIn this presentation, we present the story of the University of Mississippi Slavery Research Group focusing on its origins and the various factors that led to its formation. We highlight some of the groups’ most significant recent efforts to better understand how antebellum slavery shaped the formation of the University of Mississippi and life in North Mississippi generally and we discuss some of our initial projects and initiatives that seek to remember, memorialize and interpret the lives of enslaved people for our students, our local community, and our nation.Interpreting Slavery at Burns Belfry and Rowan Oak / George McDaniel, Burns-Belfry African American History MuseumCaroline Barr was a foundational figure in the life of William Faulkner. As he called her, “Mammy Callie,” she had worked for the Falkner family since he was a young boy. Her house and her story demand a further interpretation beyond the gates of Rowan Oak. Using her as a point of departure, this talk will explore African American history within the larger context of the town of Oxford. It will also look at the ways in which that history is being interpreted today and how that interpretation can be improved through building connections between different historical sites. This connectivity allows for a deeper understanding of African American history in Oxford and the world in which Faulkner lived and wrote

Observation of isotonic symmetry for enhanced quadrupole collectivity in neutron-rich 62,64,66Fe isotopes at N=40

The transition rates for the 2_{1}^{+} states in 62,64,66Fe were studied using the Recoil Distance Doppler-Shift technique applied to projectile Coulomb excitation reactions. The deduced E2 strengths illustrate the enhanced collectivity of the neutron-rich Fe isotopes up to N=40. The results are interpreted by the generalized concept of valence proton symmetry which describes the evolution of nuclear structure around N=40 as governed by the number of valence protons with respect to Z~30. The deformation suggested by the experimental data is reproduced by state-of-the-art shell calculations with a new effective interaction developed for the fpgd valence space.Comment: 4 pages, 2 figure

Multi-Layer Cyber-Physical Security and Resilience for Smart Grid

The smart grid is a large-scale complex system that integrates communication technologies with the physical layer operation of the energy systems. Security and resilience mechanisms by design are important to provide guarantee operations for the system. This chapter provides a layered perspective of the smart grid security and discusses game and decision theory as a tool to model the interactions among system components and the interaction between attackers and the system. We discuss game-theoretic applications and challenges in the design of cross-layer robust and resilient controller, secure network routing protocol at the data communication and networking layers, and the challenges of the information security at the management layer of the grid. The chapter will discuss the future directions of using game-theoretic tools in addressing multi-layer security issues in the smart grid.Comment: 16 page

Mirror Energy Differences at Large Isospin Studied through Direct Two-Nucleon Knockout

The first spectroscopy of excited states in 52Ni (Tz=2) and 51Co (Tz=-3/2) has been obtained using the highly selective two-neutron knockout reaction. Mirror energy differences between isobaric analogue states in these nuclei and their mirror partners are interpreted in terms of isospin nonconserving effects. A comparison between large scale shell-model calculations and data provides the most compelling evidence to date that both electromagnetic and an additional isospin nonconserving interactions for J=2 couplings, of unknown origin, are required to obtain good agreement.Comment: Accepted for publication in Physical Review Letter

Factors associated with the decision to investigate child protective services referrals: a systematic review

Background: Limited resources for child protection create challenging decision situations for child protective services (CPS) workers at the point of intake. A body of research has examined the factors associated with worker decisions and processes using a variety of methodological approaches to gain knowledge on decision-making. However, few attempts have been made to systematically review this literature. Objective: As part of a larger project on decision-making at intake, this systematic review addressed the question of the factors associated with worker decisions to investigate alleged maltreatment referrals. Methods: Quantitative studies that examined factors associated with screening decisions in CPS practice settings were included in the review. Database and other search methods were used to identify research published in English over a 35-year period (1980-2015). Findings: Of 1,147 identified sources, 18 studies were selected for full data extraction. The studies were conducted in the U.S., Canada, and Sweden and varied in methodological quality. Most studies examined case factors with few studies examining other domains. Conclusions: To inform CPS policy and practice, additional research is needed to examine the relationships between decision-making factors and case outcomes. Greater attention needs to be given to the organizational and external factors that influence decision-making