Spring Comes With The Years

Last period in Mrs. Lubell\u27s sixth-grade social studies class was always hard to sit through, especially on the warm spring days when subtle lilac fragrances and sparrow soliloquies were lifted through the flung-open windows of the second-floor classroom..

Neutrino-nucleus coherent scattering as a probe of neutron density distributions

Neutrino-nucleus coherent elastic scattering provides a theoretically appealing way to measure the neutron part of nuclear form factors. Using an expansion of form factors into moments, we show that neutrinos from stopped pions can probe not only the second moment of the form factor (the neutron radius) but also the fourth moment. Using simple Monte Carlo techniques for argon, germanium, and xenon detectors of 3.5 tonnes, 1.5 tonnes, and 300 kg, respectively, we show that the neutron radii can be found with an uncertainty of a few percent when near a neutrino flux of $3\times10^{7}$ neutrinos/cm$^{2}$/s. If the normalization of the neutrino flux is known independently, one can determine the moments accurately enough to discriminate among the predictions of various nuclear energy functionals.Comment: 10 pages, 5 figure

The Hunt for No Neutrinos

Four experiments have demonstrated new levels of sensitivity to neutrinoless double-beta decay, a process whose existence would prove that neutrinos are their own antiparticles

Adaptation and the Courtroom: Judging Climate Science

Climate science is increasingly showing up in courtroom disputes over the duty to adapt to climate change. While judges play a critical role in evaluating scientific evidence, they are not apt to be familiar with the basic methods of climate science nor with the role played by peer review, publication, and training of climate scientists. This Article is an attempt to educate the bench and the bar on the basics of the discipline of climate science, which we contend is a distinct scientific discipline. We propose a series of principles to guide a judge’s evaluation of the reliability and weight to be accorded a given climate scientists’ claim or opinion. The principles are designed to aid a judge in evaluating whether the expert’s testimony complies with the Daubert test for the admissibility of scientific evidence but are broadly applicable to a judge’s evaluation of agency science-based decisions

Adaptation and the Courtroom: Judging Climate Science

Climate science is increasingly showing up in courtroom disputes over the duty to adapt to climate change. While judges play a critical role in evaluating scientific evidence, they are not apt to be familiar with the basic methods of climate science nor with the role played by peer review, publication, and training of climate scientists. This Article is an attempt to educate the bench and the bar on the basics of the discipline of climate science, which we contend is a distinct scientific discipline. We propose a series of principles to guide a judge’s evaluation of the reliability and weight to be accorded a given climate scientists’ claim or opinion. The principles are designed to aid a judge in evaluating whether the expert’s testimony complies with the Daubert test for the admissibility of scientific evidence but are broadly applicable to a judge’s evaluation of agency science-based decisions

Anatomy of nuclear matrix elements for neutrinoless double-beta decay

We show that, within the Quasiparticle Random Phase Approximation (QRPA) and the renormalized QRPA (RQRPA) based on the Bonn CD nucleon-nucleon interaction, the competition between the pairing and the neutron-proton particle-particle and particle-hole interactions causes contributions to the neutrinoless double-beta decay matrix element to nearly vanish at internucleon distances of more than 2 or 3 fermis. As a result, the matrix element is more sensitive to short-range/high-momentum physics than one naively expects. We analyze various ways of treating that physics and quantify the uncertainty it produces in the matrix elements, with three different treatments of short-range correlations.Comment: Version to appear in Phys. Rev.

Effective double-beta-decay operator for 76Ge and 82Se

We use diagrammatic many-body perturbation theory in combination with low-momentum interactions derived from chiral effective field theory to construct effective shell-model transition operators for the neutrinoless double-beta decay of 76Ge and 82Se. We include all unfolded diagrams to first- and second-order in the interaction and all singly folded diagrams that can be constructed from them. The resulting effective operator, which accounts for physics outside the shell-model space, increases the nuclear matrix element by about 20% in 76Ge and 30% in 82Se.Comment: 8 pages, 5 figure

Microfabricated pressure and shear stress sensors

A microfabricated pressure sensor. The pressure sensor comprises a raised diaphragm disposed on a substrate. The diaphragm is configured to bend in response to an applied pressure difference. A strain gauge of a conductive material is coupled to a surface of the raised diaphragm and to at least one of the substrate and a piece rigidly connected to the substrate

Nonperturbative renormalization of the neutrinoless double-beta operator in p-shell nuclei

We use Lee-Suzuki mappings and related techniques to construct effective two-body p-shell interactions and neutrinoless double-beta operators that exactly reproduce the results of large no-core-shell-model calculations of double-beta decay in nuclei with mass number A=6. We then apply the effective operators to the decay of nuclei with A=7, 8, and 10, again comparing with no-core calculations in much larger spaces. The results with the effective two-body operators are generally good. In some cases, however, they differ non-negligibly from the full no-core results, suggesting that three-body corrections to the decay operator in heavier nuclei may be important. An application of our procedure and related ideas to fp-shell nuclei such as 76Ge should be feasible within coupled-cluster theory.Comment: 6 pages, 4 figure