Measurement of the multi-TeV neutrino cross section with IceCube using Earth absorption

Neutrinos interact only very weakly, so they are extremely penetrating. However, the theoretical neutrino-nucleon interaction cross section rises with energy such that, at energies above 40 TeV, neutrinos are expected to be absorbed as they pass through the Earth. Experimentally, the cross section has been measured only at the relatively low energies (below 400 GeV) available at neutrino beams from accelerators \cite{Agashe:2014kda, Formaggio:2013kya}. Here we report the first measurement of neutrino absorption in the Earth, using a sample of 10,784 energetic upward-going neutrino-induced muons observed with the IceCube Neutrino Observatory. The flux of high-energy neutrinos transiting long paths through the Earth is attenuated compared to a reference sample that follows shorter trajectories through the Earth. Using a fit to the two-dimensional distribution of muon energy and zenith angle, we determine the cross section for neutrino energies between 6.3 TeV and 980 TeV, more than an order of magnitude higher in energy than previous measurements. The measured cross section is $1.30^{+0.21}_{-0.19}$ (stat.) $^{+0.39}_{-0.43}$ (syst.) times the prediction of the Standard Model \cite{CooperSarkar:2011pa}, consistent with the expectation for charged and neutral current interactions. We do not observe a dramatic increase in the cross section, expected in some speculative models, including those invoking new compact dimensions \cite{AlvarezMuniz:2002ga} or the production of leptoquarks \cite{Romero:2009vu}.Comment: Preprint version of Nature paper 10.1038/nature2445

Nature of the 5f states in actinide metals

Actinide elements produce a plethora of interesting physical behaviors due to the 5f states. This review compiles and analyzes progress in understanding of the electronic and magnetic structure of the 5f states in actinide metals. Particular interest is given to electron energy-loss spectroscopy and many-electron atomic spectral calculations, since there is now an appreciable library of core d -> valence f transitions for Th, U, Np, Pu, Am, and Cm. These results are interwoven and discussed against published experimental data, such as x-ray photoemission and absorption spectroscopy, transport measurements, and electron, x-ray, and neutron diffraction, as well as theoretical results, such as density-functional theory and dynamical mean-field theory.Comment: 136 pages in Word format, 29 Figures; Accepted to Reviews of Modern Physic

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Pratos e mais pratos: louças domésticas, divisões culturais e limites sociais no Rio de Janeiro, século XIX

Reply to ten comments on a paper published in the last issue of this journal. The discussion follows along six main lines: History museums, identity, ideology and the category of nation; the need of material collections and their modalities: patrimonial, operational, virtual; theater versus laboratory; visitors and their ambiguities; Public History: the museum and the academy.Resposta aos comentários de dez especialistas que contribuíram no debate de texto publicado no último número desta revista. A discussão orientou-se segundo seis tópicos principais: museus históricos, identidade, ideologia e a categoria de nação; a necessidade de acervos materiais e suas modalidades: acervo patrimonial, operacional, virtual; teatro versus laboratório; o público e suas ambigüidades; História Pública: o museu e a Academia

Systems Development and Test Center activities in the Wind Systems Program at Rocky Flats

A test center has been established with 12 machine towers of varying descriptions and eight WTGs erected to date. Additionally, two large and three small meteorological towers have been installed as well as a small irrigation system, typical of the type commonly used throughout the country. Experience with these machines has revealed a number of operational problems, but has resulted in hardware modifications by manufacturers. The other main area of effort has been to solicit and evaluate proposals for development of 8 kW, 40 kW, and High Reliability SWECS

Feasibility of eddy current measurement of ferrite content in stainless steel welds

A phase-sensitive eddy current system was used to measure the presence of ferrite in an austenitic stainless steel matrix. Measurements were made on pressed powder specimens and on a weld in Type 304L stainless steel. The data obtained showed that small amounts of ferrite, on the order of 1 to 3%, could easily be detected. Variation in ferrite with position within the weld was also detected with good reproducibility. Absolute values for the ferrite content were not obtained as accurate standards for calibration were not available. (auth

SSC San Diego San Diego, CA 92152--5001

This paper describes how a simple workload measure obtained every 2-3 minutes during the evaluation of a prototype command and control console can be used to develop an operator's workload profile as a function of other system parameters, such as track density on the tactical plot, and task loading. If system measures can be monitored regularly, functional models of operator workload can be derived, and workload levels can be interpolated to provide near-continuous workload estimates every 15-30 seconds. The resulting workload profiles can be used to identify conditions that result in potential operator overload. Profiles from several operators may be used to study team workload distribution and to derive more efficient work allocation strategies. Also discussed in the present work is how the simple unidimensional workload measure relates to multidimensional measures that differentiate between mental demand, physical demand, frustration, and other aspects of work. Multidimensional measures require more extensive reporting and are thus not suitable for administration during system testing. A common multidimensional scale, the NASA Task Load Index (TLX), was administered at the conclusion of the each evaluation session. Regression analysis revealed that the 90th percentile from the distribution of unidimensional workload estimates related to the NASA-TLX dimensions of mental effort and temporal demand in a group of 20 operators. These findings indicate that near-continuous workload profiles may be built from simple subjective workload estimates combined with system-state information, and that the workload estimates can be linked to specific behavioral dimensions as captured by more complex workload assessment scales. iii iv CONTENTS EXECUTIVE SUMMARY ......................

Assessing the interpersonal circumplex model in late childhood: The Interpersonal Behavior Questionnaire for Children

We developed the Interpersonal Behavior Questionnaire for Children with the aim of assessing the constructs of the interpersonal circumplex model, i.e., Dominance and Love and their possible combinations, via 3rd- to 5th-grade children\u2019s self- and peer reports. In the three studies presented herein we examined several psychometric properties of the questionnaire. Results demonstrated that children\u2019s ratings along the questionnaire yielded the hypothesized circumplex structure of the interpersonal variables; that they reached significant association levels with external criteria; and that they were reliable. Specifically, interrater correlations were shown to reach substantive levels when inspected in older children, when scores were aggregated over raters, and when dominant behaviors were evaluated. Overall, our findings demonstrated the tenability of the circumplex model in young ages via children\u2019s ratings. We suggest that both personality assessment and personality development research may take advantage from using children\u2019s evaluations, in addition to adults\u2019 ratings of their children\u2019s personality