Coupling of phonons to a helium atom adsorbed on graphite

We compute the self-energy for a ^4He atom adsorbed on graphite to second order in the phonon coupling. The phonon contributions amount to several degrees Kelvin. The imaginary part corresponds to a lifetime of some 10^(-11) s

Marshall University Music Department Presents a Senior Honors Recital, Nancy Cole Williams, Piano

https://mds.marshall.edu/music_perf/1160/thumbnail.jp

Senior Recital: Kevin Williams, violin

This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Music Education. Mr. Williams studies violin with Helen Kim.https://digitalcommons.kennesaw.edu/musicprograms/1799/thumbnail.jp

CATASTROPHIC FLANK COLLAPSE ON TA’U ISLAND AND SUBSEQUENT TSUNAMI: HAS THIS OCCURRED DURING THE LAST 170 YEARS?

Ta’u, the easternmost inhabited island in the Samoan Islands archipelago, exhibits a series of down-faulted benches on its southern flank, believed to be the remnant of ~30 km3 catastrophic collapse. A historical map of Ta’u charted in 1839 during the United States Exploring Expedition, which did not show the benches, suggests that the event occurred less than 170 years ago. A collapse event of this magnitude would have generated a locally devastating tsunami, with possible impacts experienced at the regional level. However, no written or oral records of such an event exist. A number of key questions thus emerge, and formed the basis for this study. Did this event actually happen within the last 170 years, and if so, how and why could it have gone unnoticed? Or, is the event much older than the impression obtained from the literature? The catastrophic flank collapse was modeled using 100 m contour-resolution bathymetry data of the Ta’u region, coupled with rational assumptions made on the geometry of the failed mass. This enabled numerical landslide- tsunami simulation in the Cornell Multigrid Coupled Tsunami Model (COMCOT). The results indicate that if an event of this magnitude occurred in the last 170 years, it could not have gone unnoticed by local inhabitants. It thus seems likely that the initial survey conducted during the Exploring Expedition was inaccurate. Nevertheless, the well-preserved nature of the benches indicates collapse relatively recently and raises the possibility of future collapse

Assessing Community Progress on the Blueprint to End Homelessness

In 2002, the Indianapolis Housing Task Force published the Blueprint to End Homelessness, an ambitious 10-year strategy to end homelessness in Indianapolis by 2012. The Blueprint called for regular reports and evaluation of progress toward the Blueprint’s goals. The Coalition for Homelessness Intervention and Prevention (CHIP), charged with moving the Blueprint forward, has completed its own annual Community Progress Reports for 2009, 2010, and 2011. This report does not seek to replicate or evaluate these or any of the many previous reports CHIP has facilitated. We take what is presented in the previous reports as accurate and eminently useful. The annual Community Progress Reports, in particular, already serve as good evaluations of progress toward the Blueprint goals. Instead, this report seeks to identify issues not yet covered, areas where data have not been collected, areas where data collection could be improved, or areas where existing data have not yet been analyzed for the purpose of assessing Blueprint goals. We have gathered and analyzed new qualitative and quantitative data from CHIP, stakeholders, the homeless, and other sources to provide additional measures of progress toward achieving the various goals stipulated in the Blueprint and to establish new measures for future assessment. Besides qualitative interviews with samples of stakeholders and homeless, we collected census data on affordable housing for Marion County, the U.S., and four other comparison counties. We conducted a Strengths, Weaknesses, Opportunities, and Threats (SWOT) Analysis of CHIP’s annual Community Progress Reports. CHIP also provided nine years’ worth of client data from the Homeless Management Information Systems (HMIS). Finally, we collected progress reports from other jurisdictions implementing ten-year/community plans and looked at those. The overarching goal of the Blueprint has not been achieved. Homelessness has not been eliminated and will not be eliminated by the 2012 date established in the Blueprint. Progress has been and continues to be made in many areas, though. It is hoped this report will help the community as it moves forward with creating a new strategic plan

Semi-analytical dark matter halos and the Jeans equation

Although N-body studies of dark matter halos show that the density profiles, rho(r), are not simple power-laws, the quantity rho/sigma^3, where sigma(r) is the velocity dispersion, is in fact a featureless power-law over ~3 decades in radius. In the first part of the paper we demonstrate, using the semi-analytic Extended Secondary Infall Model (ESIM), that the nearly scale-free nature of rho/sigma^3 is a robust feature of virialized halos in equilibrium. By examining the processes in common between numerical N-body and semi-analytic approaches, we argue that the scale-free nature of rho/sigma^3 cannot be the result of hierarchical merging, rather it must be an outcome of violent relaxation. The empirical results of the first part of the paper motivate the analytical work of the second part of the paper, where we use rho/sigma^3 proportional to r^{-alpha} as an additional constraint in the isotropic Jeans equation of hydrostatic equilibrium. Our analysis shows that the constrained Jeans equation has different types of solutions, and in particular, it admits a unique ``periodic'' solution with alpha=1.9444. We derive the analytic expression for this density profile, which asymptotes to inner and outer profiles of rho ~ r^{-0.78}, and rho ~ r^{-3.44}, respectively.Comment: 37 pg, 14 fig. Accepted to ApJ: added two figures and extended discussion. Note that an earlier related paper (conference proceedings) astro-ph/0412442 has a mistake in eq.(2.2); the correct version is eq.(5) of the present submissio