From Uranium Enrichment To Renewable Energy

The goal of this Science/Engineering visualization is to show how gigawatt quantities of renewable energy can be generated at former nuclear processing sites as they are repurposed into industrial scale electrical power generation stations. The breakthrough product of this research is the design of an integrated terrestrial solar/space energy receiving station that will produce “baseload” electricity 24 hours a day. This research focuses attention on a Cold War-era uranium enrichment facility located on 3,700 acres of land in a rural area of SE Ohio. This site is judged to be suitable for research leading to the first-ever combination ground-based and space-based solar energy production facility. Were this research to be successful in designing, constructing and testing a space solar power receiving antenna (rectenna) mated to the operational structures of a terrestrial photovoltaic farm, this facility (and others like it) could be transformed from an environmental hazard to a societal benefit. In the case of the former Portsmouth Gaseous Diffusion Plant (PORTS), it is projected that the site has the capability to produce as much renewable energy as it once consumed in the form of coal-produced electricity, when two plants were installed on the Ohio River to sustain its operation. Faculty Mentors Don Flournoy and Kyle Perkin

Research article - Comet 81P/Wild 2 under a microscope

The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales

Search for intermediate-mass black hole binaries in the third observing run of Advanced LIGO and Advanced Virgo

International audienceIntermediate-mass black holes (IMBHs) span the approximate mass range 100−105 M⊙, between black holes (BHs) that formed by stellar collapse and the supermassive BHs at the centers of galaxies. Mergers of IMBH binaries are the most energetic gravitational-wave sources accessible by the terrestrial detector network. Searches of the first two observing runs of Advanced LIGO and Advanced Virgo did not yield any significant IMBH binary signals. In the third observing run (O3), the increased network sensitivity enabled the detection of GW190521, a signal consistent with a binary merger of mass ∼150 M⊙ providing direct evidence of IMBH formation. Here, we report on a dedicated search of O3 data for further IMBH binary mergers, combining both modeled (matched filter) and model-independent search methods. We find some marginal candidates, but none are sufficiently significant to indicate detection of further IMBH mergers. We quantify the sensitivity of the individual search methods and of the combined search using a suite of IMBH binary signals obtained via numerical relativity, including the effects of spins misaligned with the binary orbital axis, and present the resulting upper limits on astrophysical merger rates. Our most stringent limit is for equal mass and aligned spin BH binary of total mass 200 M⊙ and effective aligned spin 0.8 at 0.056 Gpc−3 yr−1 (90% confidence), a factor of 3.5 more constraining than previous LIGO-Virgo limits. We also update the estimated rate of mergers similar to GW190521 to 0.08 Gpc−3 yr−1.Key words: gravitational waves / stars: black holes / black hole physicsCorresponding author: W. Del Pozzo, e-mail: [email protected]† Deceased, August 2020