Matter Wave Scattering from Ultracold Atoms in an Optical Lattice

We study matter wave scattering from an ultracold, many body atomic system trapped in an optical lattice. We determine the angular cross section that a matter wave probe sees and show that it is strongly affected by the many body phase, superfluid or Mott insulator, of the target lattice. We determine these cross sections analytically in the first Born approximation, and we examine the variation at intermediate points in the phase transition by numerically diagonalizing the Bose Hubbard Hamiltonian for a small lattice. We show that matter wave scattering offers a convenient method for non-destructively probing the quantum many body phase transition of atoms in an optical lattice.Comment: 4 pages, 2 figure

Gradeless Learning: The Effect of Eliminating Traditional Grading Practices on Student Engagement and Learning

In order for students to learn at high levels, there must be high expectations and strong feedback. Although traditional grading seems to be an inherent part of the educational system, there are multiple purposes for grades which often causes frustrations for both teachers and students. There is a need to expand the research on grading and its effect on both student learning and motivation. This action research study centered on three research questions: 1) What effect does the elimination of traditional grading practices have on student engagement in learning? 2) What impact does the removal of traditional grading practices and implementation of a reflective process have on students’ perception of their learning? 3) What effect does student self-evaluations to determine final grades have on potential grade inflation? To determine these answers traditional grading practices were eliminated, including giving points for homework, averaging grades, and giving zeroes. These were replaced by a quarterly self-reflection completed by students and presented to the teacher. Engagement data was collected as well as gradebook data in which student work was evaluated by the teacher. Data was also collected through student surveys in order to determine student perceptions of learning and engagement. The qualitative results revealed that students have a desire to learn through accurate feedback and that traditional grading practices often interfere with learning and motivation

INSTINCT

There is a convergence point of my interests that I explore in this body of work. As a service member and wildlife enthusiast, I pursue not only an outlet for my own creative expression and illustrative ambitions, but a platform to support creative advocacy for military service members and their families. With the principles of relational aesthetics and art as social practice supporting illustrative and design-centric work, I have found that convergence. This dream continues to manifest in Noble Instinct Artworks, a creative-based company I founded that incorporates the fine art methodology, business practices, and artistic collaboration with outreach potential moving forward

The Human Frontier: Building an Inclusive Organizational Culture

Is space really the final frontier, as Star Trek asserts? It seems the final frontier we have been exploring since the dawn of time is understanding ourselves and our relationships with each other. Miller and Katz (2002) say: “The creation of cultures that are truly inclusive provide the possibility of a new vision—a new human frontier.” This article uses material from U.S. pop culture from Star Trek to Woodstock and more to explore how ordinary earthlings in the present time can define, measure and build an inclusive organizational culture

Implementing a Career Development Program for Student-Athletes

When synthesized with a fundamental academic support program, a career development program can prove to be a valuable source of information and education. Guidance about careers and academic disciplines, plus the experiential opportunities that link classroom knowledge and practical experience, have been shown to be helpful in focusing the interests and energies of young adults. This article described the Wildcat Career Development Program, which was initiated at the University of Kentucky in the fall of 1991

The Dutch LESLLA Corpus

Abstract This paper describes the Dutch LESLLA data and its curation. LESLLA stands for Low-Educated Second Language and Literacy Acquisition. The data was collected for research in this field and would have been disappeared if it were not saved. Within the CLARIN project Data Curation Service the data was made into a spoken language resource and made available to other researchers

Excitonic effects on coherent phonon dynamics in single wall carbon nanotubes

We discuss how excitons can affect the generation of coherent radial breathing modes in ultrafast spectroscopy of single wall carbon nanotubes. Photoexcited excitons can be localized spatially and give rise to a spatially distributed driving force in real space which involves many phonon wavevectors of the exciton-phonon interaction. The equation of motion for the coherent phonons is modeled phenomenologically by the Klein-Gordon equation, which we solve for the oscillation amplitudes as a function of space and time. By averaging the calculated amplitudes per nanotube length, we obtain time-dependent coherent phonon amplitudes that resemble the homogeneous oscillations that are observed in some pump-probe experiments. We interpret this result to mean that the experiments are only able to see a spatial average of coherent phonon oscillations over the wavelength of light in carbon nanotubes and the microscopic details are averaged out. Our interpretation is justified by calculating the time-dependent absorption spectra resulting from the macroscopic atomic displacements induced by the coherent phonon oscillations. The calculated coherent phonon spectra including excitonic effects show the experimentally observed symmetric peaks at the nanotube transition energies in contrast to the asymmetric peaks that would be obtained if excitonic effects were not included.Comment: submitted to Phys. Rev. B on 7 May 2013, revised on 17 July and 13 August 2013, published 30 August 201

S986 in M67: A Totally-Eclipsing Binary at the Cluster Turnoff

We have discovered that the star S986 in the old open cluster M67 has detectable total eclipses of depth 0.08 mag for the primary eclipse and 0.011 mag for the secondary eclipse (in I only). We confirm the detection of a third star in spectra contributing 11.5% +/- 1.5% of the total light in V band. The radial velocity of the third star indicates that it is a cluster member, but it is unclear whether it is physically associated with the eclipsing binary. Using spectroscopic and photometric data, we deconvolve the photometry of the three stars, and find that the primary star in the eclipsing binary is significantly hotter than the turnoff. The two most likely explanations are that the primary star is in a rapid phase of evolution near core hydrogen exhaustion (associated with the turnoff gap in M67's color-magnitude diagram), or that it is a blue straggler created during a stellar collision earlier in the cluster's history. Our detection of Li in the primary star tightly constrains possible formation mechanisms in the blue straggler explanation. Because S986 is often used to constrain tidal dissipation models, this may imply that the strength of tidal effects is underestimated.Comment: 27 pages, 8 figures, accepted for A