Meson-Exchange Currents and the Strangeness Radius of 4he

Meson-exchange current contributions to the strangeness radius of $^4$He are computed in the one-boson exchange approximation. It is found that these contributions introduce a \lapp10\% correction to the one-body contribution. They should not, therefore, hamper the extraction of the nucleon strangeness radius from the parity-violating electron-$^4$He asymmetry.Comment: 9 tex pages and 2 figures (not included, available from authors on request), CEBAF Preprint #TH-93-16 and MIT Preprint CTP#223

DMP online: the Digital Curation Centre’s web-based tool for creating, maintaining and exporting data management plans

Funding bodies increasingly require researchers to produce Data Management Plans (DMPs). The Digital Curation Centre (DCC) has created DMP Online, a web-based tool which draws upon an analysis of funders’ requirements to enable researchers to create and export customisable DMPs, both at the grant application stage and during the project’s lifetime

Dipolar condensates confined in a toroidal trap: ground state and vortices

We study a Bose-Einstein condensate of 52Cr atoms confined in a toroidal trap with a variable strength of s-wave contact interactions. We analyze the effects of the anisotropic nature of the dipolar interaction by considering the magnetization axis to be perpendicular to the trap symmetry axis. In the absence of a central repulsive barrier, when the trap is purely harmonic, the effect of reducing the scattering length is a tuning of the geometry of the system: from a pancake-shaped condensate when it is large, to a cigar-shaped condensate for small scattering lengths. For a condensate in a toroidal trap, the interaction in combination with the central repulsive Gaussian barrier produces an azimuthal dependence of the particle density for a fixed radial distance. We find that along the magnetization direction the density decreases as the scattering length is reduced but presents two symmetric density peaks in the perpendicular axis. For even lower values of the scattering length we observe that the system undergoes a dipolar-induced symmetry breaking phenomenon. The whole density becomes concentrated in one of the peaks, resembling an origin-displaced cigar-shaped condensate. In this context we also analyze stationary vortex states and their associated velocity field, finding that this latter also shows a strong azimuthal dependence for small scattering lengths. The expectation value of the angular momentum along the z direction provides a qualitative measure of the difference between the velocity in the different density peaks.Comment: 9 pages, 12 figure

Coherence vortices in one spatial dimension

Coherence vortices are screw-type topological defects in the phase of Glauber's two-point degree of quantum coherence, associated with pairs of spatial points at which an ensemble-averaged stochastic quantum field is uncorrelated. Coherence vortices may be present in systems whose dimensionality is too low to support spatial vortices. We exhibit lattices of such quantum-coherence phase defects for a one-dimensional model quantum system. We discuss the physical meaning of coherence vortices and propose how they may be realized experimentally.Comment: 5 pages, 3 figure

Final-State Interactions in the Superscaling Analysis of Neutral-Current Quasielastic Neutrino Scattering

Effects of strong final-state interactions in the superscaling properties of neutral-current quasielastic neutrino cross sections are investigated using the Relativistic Impulse Approximation as guidance. First- and second-kind scaling are analyzed for neutrino beam energies ranging from 1 to 2 GeV for the cases of 12C, 16O and 40Ca. Different detection angles of the outgoing nucleon are considered in order to sample various nucleon energy regimes. Scaling of the second kind is shown to be very robust. Validity of first-kind scaling is found to be linked to the kinematics of the process. Superscaling still prevails even in the presence of very strong final-state interactions, provided that some kinematical restrains are kept, and the conditions under which superscaling can be applied to predict neutral-current quasielastic neutrino scattering are determined.Comment: 39 pages, 16 figures, accepted for publication in Phys. Rev.

Avoided intersections of nodal lines

We consider real eigen-functions of the Schr\"odinger operator in 2-d. The nodal lines of separable systems form a regular grid, and the number of nodal crossings equals the number of nodal domains. In contrast, for wave functions of non integrable systems nodal intersections are rare, and for random waves, the expected number of intersections in any finite area vanishes. However, nodal lines display characteristic avoided crossings which we study in the present work. We define a measure for the avoidance range and compute its distribution for the random waves ensemble. We show that the avoidance range distribution of wave functions of chaotic systems follow the expected random wave distributions, whereas for wave functions of classically integrable but quantum non-separable wave functions, the distribution is quite different. Thus, the study of the avoidance distribution provides more support to the conjecture that nodal structures of chaotic systems are reproduced by the predictions of the random waves ensemble.Comment: 12 pages, 4 figure

A simple model for NN correlations in quasielastic lepton-nucleus scattering

We present a covariant extension of the relativistic Fermi gas model which incorporates correlation effects in nuclei. Within this model, inspired by the BCS descriptions of systems of fermions, we obtain the nuclear spectral function and from it the superscaling function for use in treating high-energy quasielastic electroweak processes. Interestingly, this model has the capability to yield the asymmetric tail seen in the experimental scaling function.Comment: 11 pages, 6 figures, Proceedings of the Twenty Seventh International Workshop on Nuclear Theory, June 23 - 28, 2008, Rila mountains, Bulgari

Solving the Problem with Problem Solving: Increasing Leadership Selfefficacy in Female Professionals through Problem Solving

poster abstractIn today’s world women are earning more degrees and asserting themselves in the professional world more than ever before. Despite their advancements, a disparity still exists between the number of men in leadership positions and the number of women in leadership positions in the United States workforce. Women have proven themselves to be qualified for high power positions, but there is still a barrier which prevents women from attaining equality in the positions of greatest power in a variety of organizations and fields. One such barrier is gender stereotypes, which lead to gender bias and low self-efficacy. Women are perceived to be better at stereotypically “feminine” behaviors such as caretaking, and are not seen as effective problem solvers. This perception leads to problems for aspiring female professionals, as problem solving is a gauge for assessing leadership acumen and ability. If women are perceived as lacking in the area that establishes leadership ability, this may be a contributing factor to explain gender inequality in leadership positions. This study seeks to explore how female leaders can utilize a problem solving process that integrates co-design in order to increase leadership self-efficacy and be more collaborative and visible problem solvers. To do this, the areas of problem solving, codesign and self-efficacy will be explored through a variety of collaborative and generative research methods such as contextual analysis of secondary research, interviews, surveys, focus groups and interactive research sessions. Problem solving will be explored to gain a better understanding of why it is an indicator of leadership ability and how problem-solving skills can be made more visible. Co-design is a creative approach to problem solving that utilizes collaboration, creativity, visual elements, generative tools and is appropriate for a variety of contexts. By including this element into the problem solving process, women may become more confident and visible problem solvers with a variety of tools to utilize in their everyday practice. An examination of self-efficacy will determine if having a process with specific tools and methods to utilize will empower women and increase their confidence. Providing female leaders with a set of tools in the form of a problem solving process workbook to help them become more comfortable and confident with problem solving may lead them to take on more responsibility and roles that showcase their problem solving skills. By positioning themselves to demonstrate their skills, exposure to effective female problem solvers may help to evolve this gender stereotype