From Doppler velocity maps of active regions constructed from spectra obtained by the EUV Imaging Spectrometer (EIS) on the Hinode spacecraft we observe large areas of outflow (20Y50 km s À1 ) that can persist for at least a day. These outflows occur in areas of active regions that are faint in coronal spectral lines formed at typical quietSun and active region temperatures. The outflows are positively correlated with nonthermal velocities in coronal plasmas. The bulk mass motions and nonthermal velocities are derived from spectral line centroids and line widths, mostly from a strong line of Fe xii at 195.12 8. The electron temperature of the outflow regions estimated from an Fe xiii to Fe xii line intensity ratio is about (1:2Y1:4) ; 10 6 K. The electron density of the outflow regions derived from a density-sensitive intensity ratio of Fe xii lines is rather low for an active region. Most regions average around 7 ; 10 8 cm À3 , but there are variations on pixel spatial scales of about a factor of 4. We discuss results in detail for two active regions observed by EIS. Images of active regions in line intensity, line width, and line centroid are obtained by rastering the regions. We also discuss data from the active regions obtained from other orbiting spacecraft that support the conclusions obtained from analysis of the EIS spectra. The locations of the flows in the active regions with respect to the longitudinal photospheric magnetic fields suggest that these regions might be tracers of long loops and/or open magnetic fields that extend into the heliosphere, and thus the flows could possibly contribute significantly to the solar wind.

Coronal mass ejections (CMEs) are thought to be the way by which the solar corona expels accumulated magnetic helicity which is injected into the corona via several methods. DeVore (2000) suggests that a significant quantity is injected by the action of differential rotation, however Démoulin et al. (2002b), based on the study of a simple bipolar active region, show that this may not be the case. This paper studies the magnetic helicity evolution in an active region (NOAA 8100) in which the main photospheric polarities rotate around each other during five Carrington rotations. As a result of this changing orientation of the bipole, the helicity injection by differential rotation is not a monotonic function of time. Instead, it experiences a maximum and even a change of sign. In this particular active region, both differential rotation and localized shearing motions are actually depleting the coronal helicity instead of building it. During this period of five solar rotations, a high number of CMEs (35 observed, 65 estimated) erupted from the active region and the helicity carried away has been calculated, assuming that each can be modeled by a twisted flux rope. It is found that the helicity injected by differential rotation (≈ −7 × 10 42 Mx 2 ) into the active region cannot provide the amount of helicity ejected via CMEs, which is a factor 5 to 46 larger and of the opposite sign. Instead, it is proposed that the ejected helicity is provided by the twist in the sub-photospheric part of the magnetic flux tube forming the active region.

Observations using the Bent Crystal Spectrometer instrument on the Solar Maximum Mission show that turbulence and blue-shifted motions are characteristic ofthe soft X-ray plasma during the impulsive phase &flares, and are coincident with the hard X-ray bursts observed by the Hard X-ray Burst Spectrometer. A method for analysing the Ca xIx and Fe xxv spectra characteristic of the impulsive phase is presented. Non-thermal widths and blue-shifted components in the spectral lines of Ca xlx and Fe xxv indicate the presence of turbulent velocities exceeding 100 km s ~ and upward motions of 300-400 km s ~.The April 10, May 9, and June 29, 1980 flares are studied. Detailed study of the geometry of the region, inferred from the Flat Crystal Spectrometer measurements and the image of the flare detected by the Hard X-ray Imaging Spectrometer, shows that the April 10 flare has two separated footpoints bright in hard X-rays. Plasma heated to temperatures greater than 107 K rises from the footpoints. During the three minutes in which the evaporation process occurs an energy of 3.7 x 1030 ergs is deposited in the loop. At the end of the evaporation process, the total energy observed in the loop reaches its maximum value of 3 x 1030 ergs. This is consistent with the above figures, allowing for loss by radiation and conduction. Thus the energy input due to the blue-shifted plasma flowing into the flaring loop through the footpoints can account for the thermal and turbulent energy accumulated in this region during the impulsive phase.

We discuss nonthermal velocities in an active region as revealed by the Extreme-Ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft. The velocities are derived from spectral line profiles in the extremeultraviolet (EUV) from a strong line of Fe xii at 195.12 by fitting each line profile to a Gaussian function.A We compare maps of the full width at half-maximum values, the Fe xii spectral line intensity, the Fe xii Doppler shift, the electron temperature, and electron density. We find that the largest widths in the active region do not occur in the most intense regions, but seem to concentrate in less intense regions, some of which are directly adjacent to coronal loops, and some of which concentrate in regions which also exhibit relative Doppler outflows. The increased widths can also occur over extended parts of the active region.

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