Electroweak Measurements of Neutron Densities in CREX and PREX at JLab, USA

Measurement of the parity-violating electron scattering asymmetry is an established technique at Jefferson Lab and provides a new opportunity to measure the weak charge distribution and hence pin down the neutron radius in nuclei in a relatively clean and model-independent way. This is because the Z boson of the weak interaction couples primarily to neutrons. We will describe the PREX and CREX experiments on ${}^{208}$Pb and ${}^{48}$Ca respectively; these are both doubly-magic nuclei whose first excited state can be discriminated by the high resolution spectrometers at JLab. The heavier lead nucleus, with a neutron excess, provides an interpretation of the neutron skin thickness in terms of properties of bulk neutron matter. For the lighter ${}^{48}$Ca nucleus, which is also rich in neutrons, microscopic nuclear theory calculations are feasible and are sensitive to poorly constrained 3-neutron forces.Comment: A contribution to the upcoming EPJA Special Volume on Nuclear Symmetry Energ

Private International Law as an Ethic of Responsivity

This would allow it to better able to engage with the reality of the integration that it is there to promote. Based on comparative methodology, the volume examines legal practice, as revealed by national and regional case law

PREX recent results and future prospects

The PREX experiment at Jefferson Lab has measured the parityviolating electroweak asymmetry in the elastic scattering of polarized electrons from 208Pb at an energy of 1.06 GeV and a scattering angle of 5◦. Since the Z0 boson couples mainly to neutrons, this asymmetry provides a clean measurement of the neutron RMS radius Rn of the lead nucleus. In addition to being a fundamental test of nuclear models, a precise measurement of Rn pins down the density dependence of the symmetry energy of neutron rich nuclear matter, which has impacts on neutron star structure, heavy ion collisions, and atomic parity violation experiments. The asymmetry from the first measurements performed in 2010 is Apv = 657±60(stat)± 13(syst) ppb at Q2 = 0.00906 GeV/c. Prospects for follow-up experiments with 208Pb and 48Ca are discussed

Interview about Sarah Piatt with Dr. Larry R. Michaels by Dr. Elizabeth Renker

Interview conducted at the Rutherford B. Hayes Presidential Library, Fremont, Ohio.Interview with Dr. Larry R. Michaels, the scholar who produced the first modern edition of Sarah Piatt’s poetry (titled That New World: Selected Poems of Sarah Piatt 1861-1911, published in 1999) about how he came to find Sarah Piatt, leading to the publication of his groundbreaking edition. Interview conducted in Fremont, Ohio at the Rutherford B. Hayes Presidential Library by Professor Elizabeth Renker from the Department of English at The Ohio State University

Regenerative fuel cell energy storage system for a low earth orbit space station

A study was conducted to define characteristics of a Regenerative Fuel Cell System (RFCS) for low earth orbit Space Station missions. The RFCS's were defined and characterized based on both an alkaline electrolyte fuel cell integrated with an alkaline electrolyte water electrolyzer and an alkaline electrolyte fuel cell integrated with an acid solid polymer electrolyte (SPE) water electrolyzer. The study defined the operating characteristics of the systems including system weight, volume, and efficiency. A maintenance philosophy was defined and the implications of system reliability requirements and modularization were determined. Finally, an Engineering Model System was defined and a program to develop and demonstrate the EMS and pacing technology items that should be developed in parallel with the EMS were identified. The specific weight of an optimized RFCS operating at 140 F was defined as a function of system efficiency for a range of module sizes. An EMS operating at a nominal temperature of 180 F and capable of delivery of 10 kW at an overall efficiency of 55.4 percent is described. A program to develop the EMS is described including a technology development effort for pacing technology items