Microscopic origin of pairing

A brief review of recent progress in the ab intio theory of nuclear pairing is given. Nowdays several successful solutions of the ab intio BCS theory gap equation were published which show that it is a promising first step in the problem. However, the role of many-body correlations that go beyond the BCS scheme remains uncertain and requires further investigations. As an alternative, the semi-microscopic model is discussed in which the effective pairing interaction calculated from the first principles is supplemented with a small phenomenological addendum containing one phenomenological parameter universal for all medium and heavy atomic nuclei.Comment: Contribution to the Volume 50 years of Nuclear BCS edited by World Scientifi

Self-consistent Theory of Finite Fermi Systems vs Skyrme-Hartree-Fock method. Spherical nuclei

Recent results of the Fayans energy density functional (EDF) for spherical nuclei are reviewed. A comparison is made with predictions of several Skyrme EDFs. The charge radii and characteristics of the first 2^+ excitations in semi-magic nuclei are briefly discussed. The single-particle spectra of doubly magic nuclei are considered in more detail. The phonon-particle coupling effects are analyzed including the so-called tadpole term.Comment: 6 pages, 7 figures, to appear in the proceedings of the International Conference "Nuclear Structure and Relaited Topics", July 14 - July 18, 2015, Dubna, Russia. arXiv admin note: text overlap with arXiv:1401.131

An ab initio theory of double odd-even mass differences in nuclei

Two aspects of the problem of evaluating double odd-even mass differences D_2 in semi-magic nuclei are studied related to existence of two components with different properties, a superfluid nuclear subsystem and a non-superfluid one. For the superfluid subsystem, the difference D_2 is approximately equal to 2\Delta, the gap \Delta being the solution of the gap equation. For the non-superfluid subsystem, D_2 is found by solving the equation for two-particle Green function for normal systems. Both equations under consideration contain the same effective pairing interaction. For the latter, the semi-microscopic model is used in which the main term calculated from the first principles is supplemented with a small phenomenological addendum containing one phenomenological parameter supposed to be universal for all medium and heavy atomic nuclei.Comment: 7 pages, 10 figures, Report at Nuclear Structure and Related Topics, Dubna, Russia, July 2 - July 7, 201

Device prepares aluminum surfaces for welding

Dry machining technique removes original surfaces to obtain contamination free welding surface. Device straddles edge being prepared and aligns with existing edges and adjacent surfaces of workpiece while sensing device regulates cut depth. Description of prototype is given

Particle-phonon coupling effects within theory of finite Fermi systems

Recent results of the study of the particle-phonon coupling (PC) effects in odd magic and semi-magic nuclei within the self-consistent theory of finite Fermi systems are reviewed. In addition to the usual pole diagrams, the non-pole ones are considered. Their contributions are often of a crucial importance. PC corrections to the single-particle energies for $^{40}$Ca and $^{208}$Pb are presented. The quadrupole moments of odd In and Sb isotopes, the odd-proton neighbors of even Sn isotopes, are presented also with accounting for the PC corrections. At last, recently announced problem of extremely high values charge radii of heavy Ca isotopes is solved in terms of a consistent consideration of the PC effects. In all the cases, rather good description of the data is obtained.Comment: 10 pages, 6 figures, to appear in the proceedings of the Fifth Conference on NUCLEI and MESOSCOPIC Physics (NMP17), March 6-10, 2017; East Lansing, Michigan, US

In God We Trust: Reconciling Religiosity in a Secular Nation

Since its founding, the United States has been composed of a diversity of religions, making religious tolerance and the separation of church and state necessary for the maintenance of a peaceful coexistence. It is inscribed in the First Amendment of the Constitution that “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof.” Nonetheless, despite a clear institutional differentiation between religious and nonreligious spheres of society, the United States has remained, on the whole, a devout nation. In 2016, 89 percent of Americans reported that they believe in God and 72 percent said they believe in angels (“Most Americans Still Believe in God,” 2016). These facts create an apparent paradox: Americans, as a whole, fundamentally believe in a separation of church and state, yet religious imagery often pervades political discourse. Furthermore, the emergence of the Religious Right as a powerful political force would appear to contradict the premise that politics and religion occupy separate spheres in American society. However, the group’s evolution over the past 30 years and integration into mainstream society ultimately underscores the value that most Americans place on the separation of church and state and the fact that religion is able to influence American politics only insofar as it reflects the expression of individual political opinions as motivated by religious belief. Author information: Tess Saperstein is a senior government concentrator at Harvard University. Her interests include the politics of religion and the media

The Monkey\u27s Paw: Regulating the Deliberate Environmental Release of Genetically Engineered Organisms

The deliberate release of genetically engineered organisms poses uncertain but potentially grave risks to the environment. The governing federal and state environmental regulations are inefficient and do not protect environmental integrity. This Comment examines the deliberate release of genetically engineered organisms in the context of federal and state environmental laws. It concludes that the current regulatory schemes are inadequate and proposes changes to meet the goals of effective environmental regulation

Jewish Preaching in Response to Nazi Persecution and Mass Murder 1933–1945

This opening address is based on the Introduction to my forthcoming book, due out in January 2018, entitled “Agony in the Pulpit: Jewish Preaching in Response to Nazi Persecution and Mass Murder, 1933–1945.” It contains selected passages from sermons presented in chronological order, delivered by 135 rabbis in 15 countries, responding from the pulpit to what they knew, week by week, about the fate of their fellow Jews in Europe. My address does not deal directly with the content of the sermons, but rather with the challenges in using the sermons as historical sources. Here the conference theme of “The Sermon: Text and Performance” is critical. For the sermon texts that have been preserved—even texts written by the preacher and safeguarded in archival collections, or in some cases stenographically transcribed while being spoken—are obviously not the sermon itself. Such texts lack the element of performance or delivery: the sound of the preacher’s voice, the pace of speaking, the emphasis on certain words and phrases, the gestures and facial expressions, and—no less important—the reaction and response of the listeners. It is therefore the combination of text and performance that enables us to understand and appreciate the sermon as a historical source for the reaction to increasingly catastrophic events. The presentation on the website of both a video tape of my paper as delivered, and the printed text that was written for the delivery, is a fine example of these two components of the sermon