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We have shown previously that SOHO/UVCS data allow us to detect active region (AR) outflows at coronal altitudes higher than those reached by other instrumentation. These outflows are thought to be a component of the slow solar wind. Our purpose is to study the evolution of the outflows in the intermediate corona from AR 8100, from the time the AR first forms until it dissolves, after several transits at the solar limb. Data acquired by SOHO/UVCS at the time of the AR limb transits, at medium latitudes and at altitudes ranging from 1.5 to 2.3 R_sun, were used to infer the physical properties of the outflows through the AR evolution. To this end, we applied the Doppler dimming technique to UVCS spectra. These spectra include the H I Lyman alpha line and the O VI doublet lines at 1031.9 and 1037.6 A. Plasma speeds and electron densities of the outflows were inferred over several rotations of the Sun. AR outflows are present in the newly born AR and persist throughout the entire AR life. Moreover, we found two types of outflows at different latitudes, both possibly originating in the same negative polarity area of the AR. We also analyzed the behavior of the Si XII 520 A line along the UVCS slit in an attempt to reveal changes in the Si abundance when different regions are traversed. Although we found some evidence for a Si enrichment in the AR outflows, alternative interpretations are also plausible. Our results demonstrate that outflows from ARs are detectable in the intermediate corona throughout the whole AR lifetime. This confirms that outflows contribute to the slow wind., Comment: 13 pages, Astronomy and Astrophysics accepted

Coronal plumes, which extend from solar coronal holes (CH) into the high corona and - possibly - into the solar wind (SW), can now continuously be studied with modern telescopes and spectrometers on spacecraft, in addition to investigations from the ground, in particular, during total eclipses. Despite the large amount of data available on these prominent features and related phenomena, many questions remained unanswered as to their generation and relative contributions to the high-speed streams emanating from CHs. An understanding of the processes of plume formation and evolution requires a better knowledge of the physical conditions at the base of CHs, in plumes and in the surrounding inter-plume regions (IPR). More specifically, information is needed on the magnetic field configuration, the electron densities and temperatures, effective ion temperatures, non-thermal motions, plume cross-sections relative to the size of a CH, the plasma bulk speeds, as well as any plume signatures in the SW. In spring 2007, the authors proposed a study on "Structure and dynamics of coronal plumes and inter-plume regions in solar coronal holes" to the International Space Science Institute (ISSI) in Bern to clarify some of these aspects by considering relevant observations and the extensive literature. This review summarizes the results and conclusions of the study. Stereoscopic observations allowed us to include three-dimensional reconstructions of plumes. Multi-instrument investigations carried out during several campaigns led to progress in some areas, such as plasma densities, temperatures, plume structure and the relation to other solar phenomena, but not all questions could be answered concerning the details of plume generation process(es) and interaction with the SW., Comment: To appear on: The Astronomy and Astrophysics Review. 72 pages, 30 figures

Ejections from the Sun can be observed with a higher resolution than in any other astrophysical object: can we build up on solar results and apply them to astrophysical objects? Aim of this work is to establish whether there is any analogy between solar ejections and ejections in microquasars and AGNs. Briefly reviewing jets properties from these objects and from the Sun, we point out some characteristics they share and indicate research areas where cross-breeeding between astrophysical and solar research is likely to be productive. Preliminary results of this study suggest, for instance, that there may be an analogy between blobs created by tearing instability in current sheets (CSs) associated with solar coronal mass ejections (CMEs) and quasi periodic ejections of plasma associated with large radio outbursts in microquasars., Comment: 4 pages, 1 figure, conference "Steady Jets and Transient Jets, Characteristics and Relationship", held in Bonn, Germany, 7-8 April 2010, to be published in Memorie della Societa Astronomica Italiana

Eruption of a coronal mass ejection (CME) drags and "opens" the coronal magnetic field, presumably leading to the formation of a large-scale current sheet and the field relaxation by magnetic reconnection. We analyze physical characteristics of ray-like coronal features formed in the aftermath of CMEs, to check if the interpretation of this phenomenon in terms of reconnecting current sheet is consistent with the observations. The study is focused on measurements of the ray width, density excess, and coronal velocity field as a function of the radial distance. The morphology of rays indicates that they occur as a consequence of Petschek-like reconnection in the large scale current sheet formed in the wake of CME. The hypothesis is supported by the flow pattern, often showing outflows along the ray, and sometimes also inflows into the ray. The inferred inflow velocities range from 3 to 30 km s$^{-1}$, consistent with the narrow opening-angle of rays, adding up to a few degrees. The density of rays is an order of magnitude larger than in the ambient corona. The density-excess measurements are compared with the results of the analytical model in which the Petschek-like reconnection geometry is applied to the vertical current sheet, taking into account the decrease of the external coronal density and magnetic field with height. The model results are consistent with the observations, revealing that the main cause of the density excess in rays is a transport of the dense plasma from lower to larger heights by the reconnection outflow.

During quadrature, plasma seen on the limb of the Sun, along the radi al direction to Ulysses, by SOHO or STEREO can be sampled in situ as lt later passes Ulysses. A figure shows a coronagraph image, the rad ial towards Ulysses at 58 deg. S. and the SOHO/UVCS slit positions d uring one set of observations. A CME subsequently occurred and passed Ulysses (at 3/4 AU) 15 days later.

During SOHO-Sun-Ulysses quadratures the geometry of the configuration makes it possible to sample "in situ" the plasma parcels that are remotely observed in the corona. Although the quadrature position occurs at a well defined instant in time, we typically take data while Ulysses is within +/- 5 degrees of the limb, with the understanding that plasma sampled by Ulysses over this time interval can all be traced to its source in the corona. The relative positions of SOHO and Ulysses in winter 2007 (19 Dec 2006-28 May 2007) are unusual: the SOHO-Sun-Ulysses included angle is always between 85 and 95 degrees - the quadrature lasts for 5 months! This provides an opportunity for extended observations of specific observing objectives. In addition, in summer 2007, Ulysses (at 1.34 AU) is in near-radial alignment with Earth/ACE/Wind and SOHO, allowing us to analyze radial gradients and propagation in the solar wind and inner heliosphere. Our own quadrature campaigns rely heavily on LASCO and UVCS coronal observations: LASCO giving the overall context above 2 solar radii while the UVCS spectrograph acquired data from - 1.5 to, typically, 4-5 solar radii. In the past, coronal parameters have been derived from data acquired by these two experiments and compared with "in situ" data of Ulysses' SWOOPS and SWICS. Data from other experiments like EIT, CDS, SUMER, Sac Peak Fe XIV maps, magnetic field maps from the Wilcox solar magnetograph, MLSO, from MDI, and from the Ulysses magnetograph experiment have been, and will be, used to complement LASCO/UVCS/SWOOPS and SWICS data. We anticipate that observations by ACE/WIND/STEREO/Hinode and other missions will be relevant as well. During the IHY campaigns, Ulysses will be 52-80 degrees south in winter 2007, near sunspot minimum. Hence, our own scientific objective will be to sample high speed wind or regions of transition between slow and fast wind. This might be a very interesting situation - not met in previous quadratures - allowing us to study the variation of element abundances across streamer borders in the corona and,correspondingly, "in situ". Also, observing plasma over prolonged time intervals and at different latitudes, we may examine the latitude variation of the fractionation effect (e.g. Yon Steiger, 2002) and its dependence on time (e.g. Woo, 2004). For instance, if the FIP bias is dictated by the duration of plasma confinement in solar loops, its value in streamers should depend on the streamer age. Analogous variations should be found in the abundances of "in situ" plasma released by the streamer. All Ulysses and SOHO data is in the public domain and accessible so different objectives could be addressed by others. The winter 2008 quadrature will be well into the next sunspot cycle and there might be significant high mid-latitude activity. Ulysses will be up to 80 degrees in the northern hemisphere at this time and able to detect the resulting ICMEs and ejecta, allowing us to study the physical parameters of the propagating CME bubble/core/front, and/or to study the coronal and "in situ" characteristics of the current sheet associated with the event (e.g. Bemporad et al. 2005), so far still vaguely defined.

We report on observations acquired in May 2003 during a SOHO-Ulysses quadrature campaign. From May 25 to May 28, the SoHO LASCO Coronal Mass Ejection (CME) catalog lists a number of events which might have been observed by SOHO/UVCS, whose slit was centered along the Ulysses direction. However, because of time gaps in the observing schedule, or because of the unfavorable position of some CMEs, the most interesting events recorded by UVCS were a few short-lived ejections that represent the extension at higher altitudes of recursive EIT jets. We focus on jets occurring on May 26/27, visible also in EIT and LASCO images, which seem to propagate along the radial to Ulysses. UVCS spectra at 1.7 Rsun showed an unusually high emission in cool lines, lasting for about 10 to 25 minutes, with no evidence of hot plasma. Analysis of the cool line emission allowed us to infer the evolution of physical parameters during the jets lifetime and derive a crude estimate of the energy needed to account for their properties. We also looked for any evidence of the event in in situ data. Whether UVCS is observing jets or narrow CMEs is discussed in the contest of previous works on these classes of events and, in the last Section, we propose a scenario that accounts for our observations.

At the time of the spring 2003 Ulysses-SOHO-Sun quadrature, Ulysses was off the East limb of the Sun at 14.5 degrees north latitude and 4.91 AU. LASCO/C2 images show small transient events that originated from near the limb on May 25, 26 and 27 in the north-east quadrant, along with a large Coronal Mass Ejection (CME) that originated from an active region near disk center on May 26. Ulysses data bear clear signatures of the large CME, specifically including an enhanced abundance of highly ionized Fe. SOHO/UVCS spectra at 1.75 solar radii, near the radial direction to Ulysses, give no evidence of emission from high temperature lines, even for the large CME: instead, for the small events, occasional transient high emission in cool lines was observed, such as the CIII 977 Angstrom line usually absent at coronal levels. Each of these events lasted ca. 1 hour or less and never affected lines from ions forming above ca. 106K. Compact eruptions in Helium 304 Angstrom EIT images, related to the small UVCS transients, were observed at the limb of the Sun over the same period. At least one of these surge events produced a narrow CME observed in LASCO/C2. Most probably all these events are compact magnetic explosions (surges/jets, from around a small island of included polarity) which ejected cool material from lower levels. Ulysses data have been analyzed to find evidence of the cool, narrow CME events, but none or little was found. This puzzling scenario, where events seen by UVCS have no in situ counterparts and vice versa, can be partially explained once the region where the large CME originated is recognized as being at the center of the solar disk so that the CME material was actually much further from the Sun than the 1.7 Rsun height of the UVCS slit off the limb. Conversely, the narrow events may simply have missed Ulysses or been too brief for reliable signatures in composition and ionization state. A basic feature demonstrated by these observations is that large magnetic explosions produce wide-angle CMEs whereas compact magnetic explosions produce narrow CMEs. The results show that quadrature observations need some luck to be successfull: that is, events must be in the plane of the sky to allow SOHO/UVCS and Ulysses to sample the same plasma. This will most easily occur in winter 2007 and winter 2008, when the quadrature geometry will allow for prolonged observations.

With the launch of SOHO, it again became possible to carry out quadrature observations. In comparison with earlier observations, the new capabilities of coronal spectroscopy with UVCS and in situ ionization state and composition with Ulysses/SWICS enabled new types of studies. Results from two studies serve as examples: (i) The acceleration profile of wind from small coronal holes. (ii) A high-coronal reconnecting current sheet as the source of high ionization state Fe in a CME at Ulysses. Generally quadrature observations last only for a few days, when Ulysses is within ca. 5 degrees of the limb. This means luck is required for the phenomenon of interest to lie along the radial direction to Ulysses. However, when Ulysses is at high southern latitude in winter 2007 and high northern latitude in winter 2008, there will be unusually favorable configurations for quadrature observations with SOHO and corresponding bracketing limb observations from STEREO A/B. Specifically, Ulysses will be within 5 degrees of the limb from December 2006 to May 2007 and within 10 degrees of the limb from December 2007 to May 2008. These long-lasting quadratures and bracketing STEREO A/B observations overcome the limitations inherent in the short observation intervals of typical quadratures. Furthermore, ionization and charge state measurements like those on Ulysses will also be made on STEREO and these will be essential for identification of CME ejecta - one of the prime objectives for STEREO.

We report on SOHO UVCS observations of the coronal restructuring following a coronal mass ejection (CME) on 2002 November 26, at the time of a SOHO-Ulysses quadrature campaign. Starting about 1.5 hr after a CME in the northwest quadrant, UVCS began taking spectra at 1.7 R, covering emission from both cool and hot plasma. Observations continued, with occasional gaps, for more than 2 days. Emission in the 974.8 A line of [Fe XVIII], indicating temperatures above 6 x 10(exp 6) K, was observed throughout the campaign in a spatially limited location. Comparison with EIT images shows the [Fe XVIII] emission to overlie a growing post-flare loop system formed in the aftermath of the CME. The emission most likely originates in a current sheet overlying the arcade. Analysis of the [Fe XVIII] emission allows us to infer the evolution of physical parameters in the current sheet over the entire span of our observations: in particular, we give the temperature versus time in the current sheet and estimate its density. At the time of the quadrature, Ulysses was directly above the location of the CME and intercepted the ejecta. High ionization state Fe was detected by the Ulysses SWICS throughout the magnetic cloud associated with the CME, although its rapid temporal variation suggests bursty, rather than smooth, reconnection in the coronal current sheet. The SOHO-Ulysses data set provided us with the unique opportunity of analyzing a current sheet structure from its lowest coronal levels out to its in situ properties. Both the remote and in situ observations are compared with predictions of theoretical CME models.

We report on SOHO-UVCS observations of the coronal restructuring following a Coronal Mass Ejection (CME) on November 26,2002, at the time of a SOHO-Ulysses quadrature campaign. Starting about 3 hours after a CME in the NW quadrant, UVCS began taking spectra at 1.7 solar radius, covering emission from both cool and hot plasma. Observations continued, with occasional gaps, for more than 2 days. Emission in the 974.8 Angstrom line of [Fe XVIII], indicating temperatures above 6 x 10(exp 6) K, was observed throughout the campaign in a spatially limited location. Comparison with EIT images shows the Fe XVIII emission to overlie a growing post-flare loop system formed in the aftermath of the CME. The emission most likely originates in a current sheet overlying the arcade. Analysis of the [Fe XVIII] emission allows us to infer the evolution of physical parameters in the current sheet over the entire span of our observations: in particular, we give the temperature vs. time in the current sheet and estimate the density. At the time of the quadrature, Ulysses was directly above the location of the CME and intercepted the ejecta. High ionization state Fe was detected by Ulysses-SWICS throughout the magnetic cloud associated with the CME. Both the remote and in situ observations are compared with predictions of theoretical CME models.

We present SOHO EIT, UVCS and LASCO observations of recurrent (6 --- 8 events per day) narrow (angular widths of about 3 --- 10 degrees) Coronal Mass Ejections (CMEs) which occurred over 2002 November 26--29. The active region where the ejections originate is near the base of a coronal streamer that appears to be unperturbed by the events and keeps stable in time; hence we interpret the observed events as a new class of recursive narrow CMEs that we call "streamer puffs." EIT 304 angstrom (He II) images indicate that the puffs result from compact ejective flares embedded in the streamer, with the ejections from the flares having velocities 100 --- 200 kilometers per second. Most ejections are closely correlated with coronal "jets" seen at 1.7 solar radii in the UVCS data, and a subset of these ejections and jets correspond to streamer puffs observed in LASCO coronagraph images. There are, however, more compact flares and jets than streamer puffs during the observation period, indicating that only a subset of the flare-associated ejections are energetic enough to escape into the heliosphere.

We report on SOHO-UVCS observations of coronal restructuring following a Coronal Mass Ejection (CME) on November 26, 2002, at the time of a SOHO-Ulysses quadrature campaign. Starting about 3 hours after the CME, which was directed towards Ulysses, UVCS began taking spectra at 1.7 solar radii, covering emission from both cool and hot plasma. Observations continued, with occasional gaps, for more than 2 days. Emission in the 974.8 Angstrom line of [Fe XVIII], indicating temperatures above 6x10(6) K, was observed throughout the campaign in a spatially limited location. Comparison with EIT images shows the [Fe XVIII] emission to overlie a growing post-flare loop system formed in the aftermath of the CME. The emission most likely originates in a current sheet overlying the arcade. Analysis of the [Fe XVIII] emission allows us to infer the evolution of physical parameters in the current sheet over the entire span of our observations: in particular, we give the temperature vs. time in the current sheet and estimate the density. Ulysses was directly above the location of the CME and intercepted the ejecta. High ionization state Fe was detected by SWICS throughout the magnetic cloud associated with the CME, although the rapid temporal variation suggests bursty, rather than smooth, reconnection in the coronal current sheet. Both the remote and in situ observations are compared with predictions of theoretical CME models.

On 10 June 2000 a streamer on the southeast limb slowly disappeared from LASCO/C2 over approximately 10 hours. A small CME was reported in C2. A substantial interplanetary CME (ICME) was later detected at Ulysses, which was at quadrature with the Sun and SOHO at the time. This detection illustrates the properties of an ICME for a known solar source and demonstrates that the identification can be done even beyond 3 AU. Slow streamer blowouts such as this have long been known but are little studied. We report on the SOHO observation of a coronal mass ejection (CME) on the solar limb and the subsequent in situ detection at Ulysses, which was near quadrature at the time, above the location of the CME. SOHO-Ulysses quadrature was 13 June, when Ulysses was 3.36 AU from the Sun and 58.2 degrees south of the equator off the east limb. The slow streamer blowout was on 10 June, when the SOHO-Sun-Ulysses angle was 87 degrees.

We present here evidence for highly ionized Fe observed both in the corona, in the aftermath of a CME, and, after propagation, {\it in situ}. The apparent source temperature is $>$6 MK. To our knowledge, this is the first time that such an unambiguous identification has been made. This detection complements studies correlating other properties of plasma observed {\it in situ} to the same properties of the same plasma remotely observed at its source in the corona.

We show direct evidence for the same very hot plasma being detected remotely from SOHO in the corona and subsequently, at Ulysses in the solar wind. This is, to our knowledge, the first time that such an unambiguous identification has been made in the case of hot plasma. This detection complements studies correlating other plasma and field properties observed to the properties measured at the source in the corona. This observation takes advantage of a SOHO-Sun-Ulysses quadrature, during which the Sun-Ulysses included angle is $90^\circ$ and it is possible to observe with Ulysses instruments the same plasma that has previously been remotely observed with SOHO instruments in the corona on the limb of the Sun. The identification builds on an existing base of separate SOHO and interplanetary detections of hot plasma. SOHO/UVCS has found evidence for very hot coronal plasma in current sheets in the aftermath of CMEs in the [Fe XVIII] $\lambda$ \AA\ line, implying a temperature on the order of $6\times 10(exp 6)$ K. This temperature is unusually high even for active regions, but is compatible with the high temperature predicted in current sheets. In the solar wind, ACE data from early 1998 to middle 2000 revealed high frozen-in Fe charge state in many cases to be present in interplanetary plasma.

In this paper we report on observations acquired by the Ultra Violet Coronagraph Spectrometer (UVCS) aboard the Solar and Heliospheric Observatory (SOHO), from 10 to 17 June 2000, at the time of a SOHO-Sun-Ulysses quadrature. UVCS took data at 1.6 and 1.9 solar radii, with a slit normal to the solar radius and centered along the radial to Ulysses. A streamer complex was sampled by UVCS, throughout the quadrature campaign, giving us the opportunity to derive plasma parameters in different streamers, and to compare them with plasma properties measured in situ. Large Angle Spectroscopic Coronagraph (LASCO) images above 2 solar radii helped us understand the temporal evolution of the streamer complex. We derive densities, temperatures and elemental abundances in two streamers, which have different temperatures and element abundances. In spite of these differences, both structures have the same FIP bias. The Fe/O ratio, which may be considered a proxy for the FIP effect, was measured (\it in situ} by the Solar Wind Ion Composition Spectrometer (SWICS) aboard the Ulysses spacecraft. Values of Fe/O measured in the corona, at the sites where in situ plasma originated, agree with in situ Fe/O values.

On 10 June 2000 a streamer on the southeast limb slowly disappeared from LASCO/C2 over a period of 17 hours. Within this interval, a small CME was reported in C2. Nothing was reported in C3. The ejecta was later detected at Ulysses, which was at quadrature with the Sun and SOHO at the time. The interplanetary CME (ICME) displayed all the properties of a typical ICME. Slow streamer blowouts such as this have long been known but are little studied.

Over the last week of November 2002 SOHO/LASCO observed several Coronal Mass Ejections, most of which occurring in the NW quadrant. At that time SOHO/UVCS was involved in a SOHO-Sun-Ulysses quadrature campaign, making observations off the west limb of the Sun, at a northern latitude of 27 deg. Here we focus on data taken at 1.7 solar radii, over a time interval of approx. 7 hours, on 26/27 November 2002, when a large streamer disruption was imaged by LASCO C2 and C3 coronagraphs. UVCS spectra revealed the presence of lines from both high and low ionization ions, such as C III, O VI, Si VIII, IX, and XII, Fe X and XVIII, which brighten at different times, with a different time scale and at different positions and are apparently related to different phenomena. In particular, the intensity increase and fast disappearance of the C III 977 Angstrom line represents the passage through the UVCS slit of cold material released in a jet imaged by EIT in the He II 304 Angstrom line. The persistent presence of the Fe XVIII 974 Angstrom line is not easily related to any special feature crossing the UVCS slit. We suggest to interpret this behavior in terms of the reconnection events which lead to the formation of loops observed in the EIT He II 304 Angstrom line.

Solar and Heliospheric Observatory (SOH0)-Ulysses quadratures occur when the SOHO-Sun-Ulysses-included angle is 90 deg. These offer the opportunity to directly compare properties of plasma parcels, observed by SOHO [Dorningo et al.] in the low corona, with properties of the same parcels measured, in due time, in situ, by Ulysses [ Wenzel et al]. We refer the reader to Suess et al. for an extended discussion of SOHO-Ulysses quadrature geometry. Here it suffices to recall that there are two quadratures per year, as SOHO makes its one-year revolution around the Sun. This, because SOHO is at the L1 Lagrangian point, in essentially the same place as the Earth, while Ulysses is in a near-polar -5-year solar orbit with a perihelion of 1.34 AU and aphelion of 5.4 AU.

The Fall 1998 SOlar-Heliospheric Observatory (SOHO) - Ulysses quadrature occurred when Ulysses was at 5.2 AU, 17.4 deg South of the equator, and off the West line of the Sun. SOHO coronal observations, at heliocentric distances of a few solar radii, showed that the line through the solar center and Ulysses crossed, over the first days of observations, a dark, weakly emitting area and through the northern edge of a streamer complex during the second half of the quadrature campaign. Ulysses in situ observations showed this transition to correspond to a decrease from higher speed wind typical of coronal hole flow to low speed wind. Physical parameters (density, temperature, flow speed) of the low latitude coronal plasma sampled over the campaign are determined using constraints from what is the same plasma measured later in situ and simulating the intensities of the Hydrogen Lyman-alpha and OVI 1032 and 1037 Angstrom lines, measured by the Ultra Violet Coronagraph Spectrometer (UVCS) on SOHO. The densities, temperatures and outflow speed are compared with the same characteristic flow parameters for high-latitude fast wind streams and typical slow solar wind.