The lack of an upstream solar wind monitor poses a major challenge to any study that investigates the influence of the solar wind on the configuration and the dynamics of Saturn's magnetosphere. Here we show how Cassini MIMI/LEMMS observations of Solar Energetic Particle (SEP) and Galactic Cosmic Ray (GCR) transients, that are both linked to energetic processes in the heliosphere such us Interplanetary Coronal Mass Ejections (ICMEs) and Corotating Interaction Regions (CIRs), can be used to trace enhanced solar wind conditions at Saturn's distance. SEP protons can be easily distinguished from magnetospheric ions, particularly at the MeV energy range. Many SEPs are also accompanied by strong GCR Forbush Decreases. GCRs are detectable as a low count-rate noise signal in a large number of LEMMS channels. As SEPs and GCRs can easily penetrate into the outer and middle magnetosphere, they can be monitored continuously, even when Cassini Preprint submitted to IcarusAugust 31, 2017

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We study the origin of 3 He-rich solar energetic particles (<1 MeV nucleon −1 ) that are observed consecutively on STEREO-B, ACE, and STEREO-A spacecraft when they are separated in heliolongitude by more than 90 • . The 3 He-rich period on STEREO-B and STEREO-A commences on 2011 July 1 and 2011 July 16, respectively. The ACE 3 He-rich period consists of two sub-events starting on 2011 July 7 and 2011 July 9. We associate the STEREO-B July 1 and ACE July 7 3 He-rich events with the same sizeable active region producing X-ray flares accompanied by prompt electron events, when it was near the west solar limb as seen from the respective spacecraft. The ACE July 9 and STEREO-A July 16 events were dispersionless with enormous 3 He enrichment, lacking solar energetic electrons and occurring in corotating interaction regions. We associate these events with a small, recently emerged active region near the border of a low-latitude coronal hole that produced numerous jet-like emissions temporally correlated with type III radio bursts. For the first time we present observations of 1) solar regions with long-lasting conditions for 3 He acceleration and 2) solar energetic 3 He that is temporary confined/re-accelerated in interplanetary space. Subject headings: interplanetary medium -solar wind -Sun: flares -Sun: particle emission a event included in survey by Bučík et al. (2013a) b event included in survey by Bučík et al. (2013b) c at event start time d 320-450 keV nucleon −1 ; fluence units -particles (cm 2 sr MeV/nucleon) −1

During the 2007 and 2008 solar minimum period, STEREO, Wind, and ACE observed numerous Corotating Interaction Regions (CIRs) over spatial separations that began with all the spacecraft close to Earth, through STEREO separation angles of ∼ 80 degrees in the fall of 2008. Over 35 CIR events were of sufficient intensity to allow measurement of He and heavy ion spectra using the IMPACT/SIT, EPACT/STEP and ACE/ULEIS instruments on STEREO, Wind, and ACE, respectively. In addition to differences between the spacecraft expected on the basis of simple corotation, we observed several events where there were markedly different time-intensity profiles from one spacecraft to the next. By comparing the energetic particle intensities and spectral shapes along with solar wind speed we examine the extent to which these differences are due to temporal evolution of the CIR or due to variations in connection to a relatively stable interaction region. Comparing CIRs in the

Context. Impulsive solar energetic particle events in the inner heliosphere show the long-lasting enrichment of 3 He. Aims. We study the source regions of long-lasting 3 He-rich solar energetic particle (SEP) events Methods. We located the responsible open magnetic field regions, we combined potential field source surface extrapolations with the Parker spiral, and compared the magnetic field of the identified source regions with in situ magnetic fields. The candidate open field regions are active region plages. The activity was examined by using extreme ultraviolet images from the Solar Dynamics Observatory (SDO) and STEREO together with radio observations from STEREO and WIND. Results. Multi-day periods of 3 He-rich SEP events are associated with ion production in single active region. Small flares or coronal jets are their responsible solar sources. We also find that the 3 He enrichment may depend on the occurrence rate of coronal jets.

Solar jets are fast‐moving, elongated brightenings related to ejections seen in both images and spectra on all scales from barely visible chromospheric jets to coronal jets extending up to a few solar radii. The largest, most powerful jets are the source of type III radio bursts, energetic electrons and ions with greatly enhanced 3He and heavy element abundances. The frequent coronal jets from polar and equatorial coronal holes may contribute to the solar wind. The primary acceleration mechanism for all jets is believed to be release of magnetic stress via reconnection; however the energy buildup depends on the jets' source environment. In this review, we discuss how certain features of X‐ray and EUV jets, such as their repetition rate and association with radio emission, depends on their underlying photospheric field configurations (active regions, polar and equatorial coronal holes, and quiet Sun). (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Particle acceleration in stellar flares is ubiquitous in the Universe, however, our Sun is the only astrophysical object where energetic particles and their source flares can both be observed. The acceleration mechanism in solar flares, tremendously enhancing (up to a factor of ten thousand) rare elements like 3 He and ultra-heavy nuclei, has been puzzling for almost 50 years. Here we present some of the most intense 3 He-and Fe-rich solar energetic particle events ever reported. The events were accompanied by non-relativistic electron events and type III radio bursts. The corresponding high-resolution, extreme-ultraviolet imaging observations have revealed for the first time a helical structure in the source flare with a jet-like shape. The helical jets originated in relatively small, compact active regions, located at the coronal hole boundary. A mini-filament at the base of the jet appears to trigger these events. The events were observed with the two Solar Terrestrial Relations Observatories STEREO on the backside of the Sun, during the period of increased solar activity in 2014. The helical jets may be a distinct feature of these intense events that is related to the production of high 3 He and Fe enrichments.

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