24,078 research outputs found

    Modeling Evolving Coronal Loops with Observations from STEREO, Hinode, and TRACE

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    The high densities, long lifetimes, and narrow emission measure distributions observed in coronal loops with apex temperatures near 1 MK are difficult to reconcile with physical models of the solar atmosphere. It has been proposed that the observed loops are actually composed of sub-resolution ``threads'' that have been heated impulsively and are cooling. We apply this heating scenario to nearly simultaneous observations of an evolving post-flare loop arcade observed with the EUVI/\textit{STEREO}, XRT/\textit{Hinode}, and \textit{TRACE} imagers and the EIS spectrometer on \textit{HINODE}. We find that it is possible to reproduce the extended loop lifetime, high electron density, and the narrow differential emission measure with a multi-thread hydrodynamic model provided that the time scale for the energy release is sufficiently short. The model, however, does not reproduce the evolution of the very high temperature emission observed with XRT. In XRT the emission appears diffuse and it may be that this discrepancy is simply due to the difficulty of isolating individual loops at these temperatures. This discrepancy may also reflect fundamental problems with our understanding of post-reconnection dynamics during the conductive cooling phase of loop evolution.Comment: Revised version submitted to ApJ in response to referee's comment

    INTRODUCING FOODS PRODUCED USING BIOTECHNOLOGY: THE CASE OF BOVINE SOMATOTROPIN

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    A mailed questionnaire was used to assess consumer concerns and potential consumption response attributable to the introduction of bovine somatotropin (bST). Responses from 605 households in Virginia are described and analyzed. Logit models were estimated to identify which issues shape consumersÂ’ decisions to alter milk purchases contingent on the introduction of bST and to determine whether socioeconomic characteristics explain consumersÂ’ attitudes toward these issues. Estimates based on survey responses point toward sizable reductions in fluid milk purchases if bST is introduced. Large retail price reductions are predicted to be insufficient to offset these estimated decreases. Consumer education and marketing strategies are discussed.Food Consumption/Nutrition/Food Safety, Research and Development/Tech Change/Emerging Technologies,

    A proposed DAQ system for a calorimeter at the International Linear Collider

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    This note describes R&D to be carried out on the data acquisition system for a calorimeter at the future International Linear Collider. A generic calorimeter and data acquisition system is described. Within this framework modified designs and potential bottlenecks within the current system are described. Solutions leading up to a technical design report will to be carried out within CALICE-UK groups.Comment: 13 pages, 4 figure
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