caa a22 4500 445347163 CHVBK 20180317142832.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s11207-011-9862-y doi (NATIONALLICENCE)springer-10.1007/s11207-011-9862-y The EVE Doppler Sensitivity and Flare Observations [Elektronische Daten] [H. Hudson, T. Woods, P. Chamberlin, L. Fletcher, G. Del Zanna, L. Didkovsky, N. Labrosse, D. Graham] The Extreme-ultraviolet Variability Experiment (EVE; see Woods et al., 2009) obtains continuous EUV spectra of the Sun viewed as a star. Its primary objective is the characterization of solar spectral irradiance, but its sensitivity and stability make it extremely interesting for observations of variability on time scales down to the limit imposed by its basic 10s sample interval. In this paper we characterize the Doppler sensitivity of the EVE data. We find that the 30.4nm line of Heii has a random Doppler error below 0.001nm (1pm, better than 10km s−1 as a redshift), with ample stability to detect the orbital motion of its satellite, the Solar Dynamics Observatory (SDO). Solar flares also displace the spectrum, both because of Doppler shifts and because of EVE's optical layout, which (as with a slitless spectrograph) confuses position and wavelength. As a flare develops, the centroid of the line displays variations that reflect Doppler shifts and therefore flare dynamics. For the impulsive phase of the flare SOL2010-06-12, we find the line centroid to have a redshift of 16.8±5.9km s−1 relative to that of the flare gradual phase (statistical errors only). We find also that high-temperature lines, such as Fexxiv 19.2nm, have well-determined Doppler components for major flares, with decreasing apparent blueshifts as expected from chromospheric evaporation flows. Springer Science+Business Media B.V., 2011 Sun: flares nationallicence Sun: photosphere nationallicence Hudson H. SSL, UC Berkeley, 94720, Berkeley, CA, USA aut Woods T. Laboratory for Atmospheric and Space Physics, University of Colorado, 1234 Innovation Dr., 80303, Boulder, CO, USA aut Chamberlin P. NASA Goddard Space Flight Center, Greenbelt, MD, USA aut Fletcher L. School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, UK aut Del Zanna G. University of Cambridge, Cambridge, UK aut Didkovsky L. Space Sciences Center, University of Southern California, 90089, Los Angeles, CA, USA aut Labrosse N. School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, UK aut Graham D. School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, UK aut Solar Physics Springer Netherlands 273/1(2011-10-01), 69-80 0038-0938 273:1<69 2011 273 11207 https://doi.org/10.1007/s11207-011-9862-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11207-011-9862-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hudson H. SSL, UC Berkeley, 94720, Berkeley, CA, USA aut NATIONALLICENCE 700 1- Woods T. Laboratory for Atmospheric and Space Physics, University of Colorado, 1234 Innovation Dr., 80303, Boulder, CO, USA aut NATIONALLICENCE 700 1- Chamberlin P. NASA Goddard Space Flight Center, Greenbelt, MD, USA aut NATIONALLICENCE 700 1- Fletcher L. School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, UK aut NATIONALLICENCE 700 1- Del Zanna G. University of Cambridge, Cambridge, UK aut NATIONALLICENCE 700 1- Didkovsky L. Space Sciences Center, University of Southern California, 90089, Los Angeles, CA, USA aut NATIONALLICENCE 700 1- Labrosse N. School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, UK aut NATIONALLICENCE 700 1- Graham D. School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, UK aut NATIONALLICENCE 773 0- Solar Physics Springer Netherlands 273/1(2011-10-01), 69-80 0038-0938 273:1<69 2011 273 11207 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer