13,076 research outputs found
Meson-Exchange Currents and the Strangeness Radius of 4he
Meson-exchange current contributions to the strangeness radius of 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-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
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
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
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
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