Absolute radiometric calibration of the EUNIS-06 170-205 A channel and calibration update for CDS/NIS

The Extreme-Ultraviolet Normal-Incidence Spectrograph sounding-rocket payload was flown on 2006 April 12 (EUNIS-06), carrying two independent imaging spectrographs covering wave bands of 300-370 A in first order and 170-205 A in second order, respectively. The absolute radiometric response of the EUNIS-06 long-wavelength (LW) channel was directly measured in the same facility used to calibrate CDS prior to the SOHO launch. Because the absolute calibration of the short-wavelength (SW) channel could not be obtained from the same lab configuration, we here present a technique to derive it using a combination of solar LW spectra and density- and temperature-insensitive line intensity ratios. The first step in this procedure is to use the coordinated, cospatial EUNIS and SOHO/CDS spectra to carry out an intensity calibration update for the CDS NIS-1 waveband, which shows that its efficiency has decreased by a factor about 1.7 compared to that of the previously implemented calibration. Then, theoretical insensitive line ratios obtained from CHIANTI allow us to determine absolute intensities of emission lines within the EUNIS SW bandpass from those of cospatial CDS/NIS-1 spectra after the EUNIS LW calibration correction. A total of 12 ratios derived from intensities of 5 CDS and 12 SW emission lines from Fe Fe X - Fe XIII yield an instrumental response curve for the EUNIS-06 SW channel that matches well to a relative calibration which relied on combining measurements of individual optical components. Taking into account all potential sources of error, we estimate that the EUNIS-06 SW absolute calibration is accurate to about 20%.Comment: 11 pages, 10 figures, 4 tables. 2010, ApJ Suppl. In pres

Underflight calibration of SOHO/CDS and Hinode/EIS with EUNIS-07

Flights of Goddard Space Flight Center's Extreme-Ultraviolet Normal-Incidence Spectrograph (EUNIS) sounding rocket in 2006 and 2007 provided updated radiometric calibrations for SOHO/CDS and Hinode/EIS. EUNIS carried two independent imaging spectrographs covering wavebands of 300-370 A in first order and 170-205 A in second order. After each flight, end-to-end radiometric calibrations of the rocket payload were carried out in the same facility used for pre-launch calibrations of CDS and EIS. During the 2007 flight, EUNIS, SOHO CDS and Hinode EIS observed the same solar locations, allowing the EUNIS calibrations to be directly applied to both CDS and EIS. The measured CDS NIS 1 line intensities calibrated with the standard (version 4) responsivities with the standard long-term corrections are found to be too low by a factor of 1.5 due to the decrease in responsivity. The EIS calibration update is performed in two ways. One is using the direct calibration transfer of the calibrated EUNIS-07 short wavelength (SW) channel. The other is using the insensitive line pairs, in which one member was observed by EUNIS-07 long wavelength (LW) channel and the other by EIS in either LW or SW waveband. Measurements from both methods are in good agreement, and confirm (within the measurement uncertainties) the EIS responsivity measured directly before the instrument's launch. The measurements also suggest that the EIS responsivity decreased by a factor of about 1.2 after the first year of operation. The shape of the EIS SW response curve obtained by EUNIS-07 is consistent with the one measured in laboratory prior to launch. The absolute value of the quiet-Sun He II 304 A intensity measured by EUNIS-07 is consistent with the radiance measured by CDS NIS in quiet regions near the disk center and the solar minimum irradiance obtained by CDS NIS and SDO/EVE recently.Comment: 16 pages, 14 figures, 5 tables, accepted by ApJ Supplement (Sep. 2011

Linfield Student Cookbook

The Linfield Student Health, Wellness and Counseling Center has been working to meet students\u27 nutritional needs by creating a student cookbook, suitable for use in limited kitchen space. We have become aware that Linfield students are interested in nutrition and wellness but may not have a full kitchen or budget to work with. By creating and distributing this cookbook, we hope that students will be able to utilize it as a resource to learn more about healthy eating and put this knowledge into practice, working toward the ultimate goal of lifelong wellness

Evidence of Explosive Evaporation in a Microflare Observed by Hinode/EIS

We present a detailed study of explosive chromospheric evaporation during a microflare which occurred on 2007 December 7 as observed with the EUV Imaging Spectrometer (EIS) onboard Hinode. We find temperature-dependent upflows for lines formed from 1.0 to 2.5 MK and downflows for lines formed from 0.05 to 0.63 MK in the impulsive phase of the flare. Both the line intensity and the nonthermal line width appear enhanced in most of the lines and are temporally correlated with the time when significant evaporation was observed. Our results are consistent with the numerical simulations of flare models, which take into account a strong nonthermal electron beam in producing the explosive chromospheric evaporation. The explosive evaporation observed in this microflare implies that the same dynamic processes may exist in events with very different magnitudes.Comment: 14 pages, 8 figures. Accepted for publication in the Astrophysical Journa

Different Patterns of Chromospheric Evaporation in a Flaring Region Observed with Hinode/EIS

We investigate the chromospheric evaporation in the flare of 2007 January 16 using line profiles observed by the EUV Imaging Spectrometer (EIS) onboard Hinode. Three points at flare ribbons of different magnetic polarities are analyzed in detail. We find that the three points show different patterns of upflows and downflows in the impulsive phase of the flare. The spectral lines at the first point are mostly blue shifted, with the hotter lines showing a dominant blue-shifted component over the stationary one. At the second point, however, only weak upflows are detected; in stead, notable downflows appear at high temperatures (up to 2.5-5.0 MK). The third point is similar to the second one only that it shows evidence of multi-component downflows. While the evaporated plasma falling back down as warm rain is a possible cause of the redshifts at points 2 and 3, the different patterns of chromospheric evaporation at the three points imply existence of different heating mechanisms in the flaring active region.Comment: 18 pages, 7 figures, 2 tables. Accepted for publication in Ap

The problem of causality in cultivation research

This paper offers an up-to-date review of problems in determining causal relationships in cultivation research, and considers the research rationales of various approaches with special reference to causal interpretation. It describes in turn a number of methodologies for addressing the problem and resolving it as far as this is possible. The issue of causal inference arises not only in cultivation research, however, but is basic to all media effects theories and approaches primarily at the macro-level whose main methodology rests on correlational studies (agenda-setting, spiral of silence, knowledge gap hypothesis, etc.). We therefore first discuss problems of causal interpretation in connection with the cultivation hypothesis, and then sketch in summary how these problems arise with other media effects theories. We first set out the basic features of the cultivation approach, then consider the difficulties with correlational studies and discuss alternative research designs - designs which are not original to us, but have been adapted for cultivation research. These comprise laboratory experiments, sequential studies, social studies and time-series procedures. Finally, we argue for multiple approaches that complement one another's advantages and balance out their disadvantages

Spatially-Resolved Nonthermal Line Broadening During The Impulsive Phase of a Solar Flare

This paper presents a detailed study of excess line broadening in EUV emission lines during the impulsive phase of a C-class solar flare. In this work, which utilizes data from the EUV Imaging Spectrometer (EIS) onboard Hinode, the broadened line profiles were observed to be co-spatial with the two HXR footpoints as observed by RHESSI. By plotting the derived nonthermal velocity for each pixel within the Fe XV and Fe XVI rasters against its corresponding Doppler velocity a strong correlation (|r| > 0.59) was found between the two parameters for one of the footpoints. This suggested that the excess broadening at these temperatures is due to a superposition of flows (turbulence), presumably as a result of chromospheric evaporation due to nonthermal electrons. Also presented are diagnostics of electron densities using five pairs of density-sensitive line ratios. Density maps derived using the Mg XII and Si X line pairs showed no appreciable increase in electron density at the footpoints, while the Fe XII, Fe XIII, and Fe XIV line pairs revealed densities approaching 10^(11.5) cm^(-3). Using this information, the nonthermal velocities derived from the widths of the two Fe XIV lines were plotted against their corresponding density values derived from their ratio. This showed that pixels with large nonthermal velocities were associated with pixels of moderately higher densities. This suggests that nonthermal broadening at these temperatures may have been due to enhanced densities at the footpoints, although estimates of the amount of opacity broadening and pressure broadening appeared to be negligible.Comment: 11 pages, 10 figures. Accepted to Ap

Non-linear model-predictive-control for thermomechanical ring rolling

he authors present a new ring rolling variant that combines a semi-warm forming process of a bearing ring with controlled cooling directly followed by a cold forming process. The aim is to produce near net shape rings with a selected microstructure and high strength without additional consecutive heat treatment. To achieve this, a new and fast control strategy is necessary that not only controls the geometrical forming of the ring, but also considers temperature development and microstructure formation. The proposed control strategy is based on the application of a fast semi-analytical simulation model with a very short response time in combination with a FE-analysis of the thermomechanical ring rolling process. The semianalytical model is used as a predictor and a parallel FEA or experimental results as a corrector for the control model. The aim is to correctly identify transient process parameters needed to achieve defined product properties as a basis for a later implementation in a non-linear modelpredictive-control of thermomechanical ring rolling. The new approach will be described in detail and demonstrated numerically and experimentally

A novel indicator for kinematic hardening effect quantification in deep drawing simulation

Deep drawing simulation techniques reduce tool design costs and improve tool performance and reliability. In terms of strain hardening, mixed models capturing the kinematic effect are sometimes more accurate than isotropic models. Indeed, nonlinearity in strain paths can lead to inconsistent simulation results. However, the use of such models requires a greater number of tests including strain path changes. Therefore, the use of such mixed models shall be required only if the simulation includes non-linear strain paths and the material exhibits a pronounced Bauschinger effect. New tools to help engineers choose between models could ease the spread of more advanced models in simulation of deep drawing processes when needed. With this in mind, an indicator predicting the influence of kinematic effects could help to select an adequate model. In this study, a new indicator is introduced with the idea of characterising strain path non-linearity in order to assess kinematic hardening influence. The indicator is computed using the forming history taken from a purely isotropic simulation – which is easier to set up and parametrise. The ability of the indicator to predict inconsistencies within the isotropic simulation is investigated using U-channel simulations