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During the GALILEO spacecraft encounter with Io in December 1995, the Energetic Particles Detector (EPD) [Williams et al., 1992] measured pitch angle distributions with high spatial and temporal resolution. All ion and electron channels show a depletion of field-aligned particles due to the interaction of trapped particles with the ionosphere / atmosphere of Jupiter. The medium nuclei channels, containing mainly sulphur and oxygen ions, show a second minimum for particles moving perpendicular to the magnetic field direction. This observation indicates that charge exchange between the singly-charged energetic ions and neutral atoms in the Io torus represents an important loss mechanism for energetic ions within the Io torus regions. Additionally, knowing the cross-sections of the involved charge exchange reactions it is possible to calculate the average neutral number density in the Io torus. The obtained result of ≈35 cm−3 is in good agreement with density estimations using ground based measurements.

Solar wind abundance ratios of magnesium isotopes measured with the high resolution Mass Time-of-Flight spectrometer (MTOF) of the Charge, Element, and Isotope Analysis System (CELIAS) experiment on board the Solar and Heliospheric Observatory (SOHO) are presented. MTOF, as part of CELIAS, is, because of its high time and mass resolution, an excellent tool for isotope abundance measurements in the solar wind. From the data analysis we have found that the isotopic composition of magnesium in the solar wind agrees with the terrestrial composition within the experimental uncertainty. We have obtained isotopic ratios of 24Mg/25Mg = 7.7 ± 0.4 and 24Mg/26Mg = 7.0 ± 0.5. These values are consistent with the terrestrial values of 24Mg/25Mg = 7.90 ± 0.01 and 24Mg/26Mg = 7.17 ± 0.03. Furthermore, these investigations also show that with the given uncertainties the abundance ratios do not vary significantly within a solar wind velocity range from 375 km/s to 530 km/s.

The High-Energy Suprathermal Time-of-Flight sensor (HSTOF) of the Charge, Element, and Isotope Analysis System (CELIAS) on the Solar and Heliospheric Observatory (SOHO) near the Lagrangian point L1 is capable of identifying energetic hydrogen atoms (EHAs) between 55 and 80 keV. Between 1996 February 13 and 1997 August 31, near solar minimum, there were 285 "quiet" days when the interplanetary charged-particle flux was low. During these quiet times, HSTOF scanned the apex of the heliosphere once and the antiapex twice. The flux level and time profile, and hence the arrival direction, of the EHAs accumulated during these quiet times are best interpreted as fluxes of EHAs coming from the heliosheath.

The CELIAS particle experiment on SOHO contains the Charge Time Of Flight (CTOF) mass spectrometer which measures the ionic and elemental composition of minor ions in the solar wind. In this paper we present iron freeze-in temperatures derived with a time resolution of 5 min. They indicate that some of the filamentary structures of the inner corona observed in Hα survive in the interplanetary medium as far as 1 AU.

The objective of this paper is to explore the structure and properties of the region between the shocked solar wind and the planetary plasma on the dayside of Mars. This study is based on the observations obtained by the plasma instruments carried on board the Phobos 2 spacecraft. These instruments have independently identified several plasma boundaries in the dayside magnetosphere of Mars, the boundaries are located close to each other but exhibit different plasma features. This investigation leads us to conclude that a dayside region exists on Mars with the following characteristics: (1) the bulk of the shocked solar wind protons are deflected, (2) the total magnetic field increases, (3) a plasma depletion region is formed, (4) both shocked solar wind and planetary plasma are present, (5) accelerated electrons and heavy ions are also present, (6) intensive wave activity is seen in the 5 to 150 Hz frequency interval, and (7) a current layer and associated magnetic shears can be identified. We name this region, located between the ionosphere and the shocked solar wind, the dayside boundary layer or dayside mantle. Its key features are similar to those of the Venus mantle; the variety of names given to the Martian plasma boundaries merely reflects its complicated structure. We conclude that the two boundary layers at Venus and Mars are very similar and that the physical processes (i.e., the interaction of the shocked solar wind with the planetary plasma) at work within these boundary layers are probably similar.

From September to October 1996 the Galileo spacecraft crossed through the distant predawn tail region of the Jovian magnetosphere. The Energetic Particles Detector (EPD) onboard Galileo recorded a series of energetic particle flow bursts in the region beyond 80 R j to the apojove at 113 R j . The events are similar in nature to an event observed with the hot plasma instrument (LECP) onboard Voyager 2. The individual events last for several hours and cover the whole energy range from 15 keV to 55 MeV. The majority of them show considerable intensity increases which are most prominent for heavy ions. The events exhibit high radially outward directed anisotropies suggesting strongly collimated radial outflowing ion beams. The Voyager event was observed beyond the corotation boundary within a magnetospheric boundary layer termed the magnetospheric wind region and consequently it was assumed that the underlying process is connected with a boundary layer instability. However, the Galileo observations show the bursts being embedded in a general corotation flow. It is thus suggested that the flow bursts are driven by an internal plasma sheet process possibly associated with a major re-configuration of the Jovian magnetotail. A series of five very prominent flow bursts observed near apojove of the orbit occurred quasi-periodically with a repetition period of about 2.6±0.2 days which is presumably related to an internal time constant of the Jovian magnetotail.

Measurements with the Energetic Particles Detector (EPD) on Galileo orbit C9 in the Jovian magnetotail revealed the existence of distinct quasi-periodic variations of energetic ion intensities which are superimposed on the well-known 10-hour modulations due to the planetary rotation. The intensity variations are associated with changes of the particle energy spectra and the plasma flow pattern. They are clearly of temporal nature and not the consequence of the spacecraft passing through periodically separated spatial structures. The modulation period is about 3 days. The oscillations are most pronounced throughout the middle magnetotail regime (20 to 80 R j ), however, seem to persist even in the deep tail region. The amplitude of the modulation is dependent on the particle energy. The highest energies measured (about I MeV) show the strongest variations. Energetic particle features with similar periodicity are observed on other Galileo orbits as well. The cause of these modulations is unclear; however, it may be speculated that they correspond to a quasi-periodic transition between two basic states of the Jovian magnetotail which occur with a time constant inherent to the Jovian magnetosphere.

The Charge and Mass Magnetospheric Ion Composition Experiment (CAMMICE) on board the Polar spacecraft observed 75 energetic particle events in 1996 while the satellite was at apogee. All of these events were associated with a decrease in the magnitude of the local magnetic field measured by the Magnetic Field Experiment (MFE) on Polar. These new events showed several unusual features: (1) They were detected in the dayside polar cusp near the apogee of Polar with about 79% of the total events in the afternoonside and 21% in the morningside; (2) an individual event could last for hours; (3) the measured helium ion had energies up to and many times in excess of 2.4 MeV; (4) the intensity of 1-200 KeV/e helium was anticorrelated with the magnitude of the local geomagnetic field but correlated with the turbulent magnetic energy density; (5) the events were associated with an enhancement of the low-frequency magnetic noise, the spectrum of which typically extends from a few hertz to a few hundreds of hertz as measured by the Plasma Wave Instrument (PWI) on Polar; and (6) a seasonal variation was found for the occurrence rate of the events with a maximum in September. These characterized a new phenomenon which we are calling cusp energetic particle (CEP) events. The observed high charge state of helium and oxygen ions in the CEP events indicates a solar source for these particles. Furthermore, the measured 0.52-1.15 MeV helium flux was proportional to the difference between the maximum and the minimum magnetic field in the event. A possible explanation is that the energetic helium ions are energized from lower energy helium by a local acceleration mechanism associated with the high-altitude dayside cusp. These observations represent a potential discovery of a major acceleration region of the magnetosphere.

We present first results taken from the high-resolution mass time-of-flight spectrometer (MTOF) of the charge, element, and isotope analysis system (CELIAS) experiment on board the Solar and Heliospheric Observatory (SOHO) spacecraft launched in December 1995, concerning the abundance ratios of neon isotopes in the solar wind. We obtain the isotopic ratios 20Ne/22Ne = (13.8 ± 0.7) and 20Ne/21Ne = (440 ± 110), which agree with the values obtained from the Apollo foil solar wind experiments and which have been derived from measurements of solar particles implanted in lunar and meteoritic samples.

On August 27, 1996, a two-hour energetic heavy ion event (∼ 1 MeV) was detected at 8:25 UT at apogee (∼ 9 R e and an invariant latitude of ∼ 80°), by the Charge and Mass Magnetospheric Ion Composition Experiment onboard POLAR. The event, with a maximum spin averaged peak flux of ∼ 150 particles/(cm 2 -sr-s-MeV), showed three local peaks corresponding to three localized regions; the ion pitch angle distributions in the three regions were different from an isotropic distribution and different from each other. No comparable flux was observed by the WIND spacecraft. The appearance of lower energy He ++ and O >+2 during the event period indicates a solar source for these particles. From region 1 to 2 to 3, the helium energy spectra softened. A distorted magnetic field with three local minima corresponding to the three He peak fluxes was also observed by POLAR. A possible explanation is that the energetic He ions were energized from lower energy helium by a local acceleration mechanism that preferred smaller rigidity ions in the high altitude polar cusp region.

We present the first observations by Polar and 1995-034 of the mid-altitude cusp. On May 29, 1996, the Polar and 1995-034 spacecraft crossed into an extended cusp region. The region was characterized by intense fluxes of solar wind like ions in the energy range 1–10 keV that had angular distributions that showed evidence of flows and trapping. The ion composition data are combined with energetic proton observations from Polar and plasma observations from 1995-034 and DMSP satellites to examine the spatial and temporal extent and plasma characteristics of the cusp during a persistent northward IMF condition. The composition data is consistent with expected solar wind composition with a source temperature of ∼1.25 × 106 K. The combined spacecraft observations show an extended cusp-like region, probably produced by northward IMF.

On January 15, 1994, the ion spectrometer high energy particle - low energy particle detector (HEP-LD) on the Japanese spacecraft Geotail observed five quasi-periodic energetic ion bursts in the deep tail (X=−96 RE). These bursts were associated with plasmoid-like structures in the magnetic field components. In. addition, three multiple TCR groups were identified in the interval. The observations in the distant tail occurred during a time interval of substorm activity which also produced multiple injections in the geosynchronous orbit region. The HEP-LD observations show that Bz bipolar plasmoid-like structures are associated with tailward flowing particle bursts. However, earthward flowing particle bursts are predominantly associated with bipolar signatures in By. In addition, an oxygen burst was seen in the back of a plasmoid (postplasmoid) which showed both By and Bz bipolar magnetic field signatures. The oxygen burst lasted for 23 min, and the density ratio (O/H) reached 15% for the HEP-LD energy range (in the same plasmoid, this ratio was approximately 1% before the oxygen burst). The oxygen burst exhibited a strong beam-like structure which occupied only 6 ∼ 7% of the full solid angle (4π). We suggest that energized oxygen ions of ionospheric origin travel downtail in the narrow postplasmoid-plasma sheet which trails the plasmoid. Furthermore, we suggest that the magnetosphere dissipated larger quantities of energy during this very intense substorm event by ejecting multiple relatively small plasmoids rather than through the formation and ejection of a single large plasmoid.

Solar wind plasma and magnetic data obtained near the Martian terminator bow shock by the TAUS energy spectrometer and the MAGMA magnetometer onboard the Phobos 2 spacecraft are analyzed. It is revealed that on average the solar wind stream is slowing down just upstream of the bow shock. Nearly inverse correlation is found between the values of the velocity decrease and the undisturbed solar wind density for the outbound (mostly quasi-parallel) bow shock crossings, while for the inbound crossings (mostly quasi-perpendicular) this correlation is observed only for the velocity decrease upstream of the shock foot. This result permits us to distinguish between the two possible reasons causing solar wind deceleration: (1) mass loading of the solar wind flow by planetary ions originating from the corona of Mars, and (2) solar wind protons reflected from the bow shock. The solar wind deceleration upstream of the bow shock foot turned to be approximately dawn-dusk symmetric. On the basis of the revealed relation between the velocity decrease and upstream solar wind density, a coronal density profile is deduced which is in agreement with earlier results for the subsolar region. According to this profile, the density of the hot oxygen corona of Mars might be ∼ 3 times higher in the period of observations than the estimations of the "extreme" corona model suggests, even taking into account the possible contribution of the hydrogen corona to the solar wind deceleration effect.

In 1989 the Phobos 2 spacecraft provided sufficient plasma and magnetic field data for statistical investigations of the Martian bow shock structure. Significant magnetic field overshoots were observed in more than 70% of the bow shock crossings detected in the terminator region. According to our studies based on the available low-resolution data set, the features of the Martian overshoots are very similar to those observed in the terrestrial and Venusian bow shock: the magnitude increases with increasing Mach number and the thickness scales as the proton gyroradius computed from the upstream solar wind speed and magnetic field strength. Our investigations seem to support the idea of Mellott and Livesey [1987] suggesting that overshoots may develop not only in supercritical shocks but also when the Mach number is below or around the critical value.

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The RAPID spectrometer (Research with Adaptive Particle Imaging Detectors) for the Cluster mission is an advanced particle detector for the analysis of suprathermal plasma distributions in the energy range from 20–400 keV for electrons, 40 keV–1500 keV (4000 keV) for hydrogen, and 10 keV nucl-1–1500 keV (4000 keV) for heavier ions. Novel detector concepts in combination with pin-hole acceptance allow the measurement of angular distributions over a range of 180° in polar angle for either species. Identification of the ionic component (particle mass A) is based on a two-dimensional analysis of the particle's velocity and energy. Electrons are identified by the well-known energy-range relationship. Details of the detection techniques and in-orbit operations are described. Scientific objectives of this investigation are highlighted by the discussion of selected critical issues in geospace.

In this study we investigate that region of the dayside magnetosphere of Mars where we may expect that the shocked solar wind comes into direct contact with the planetary ions, and where energy and momentum transfer from the solar wind to planetary plasma may take place. It is our intention to analyse whether the dominant microphysical processes are similar to those observed in the equivalent regions of the magnetosphere of Venus, that is in the dayside mantle of Venus. In this study we present results obtained along the first elliptic orbit of the Phobos 2 spacecraft. Our first conclusion is that around Mars it is the magnetic barrier region that corresponds to the dayside mantle of Venus. In this region at Mars wave excitations are observed, dominantly in the 5 to 50 Hz region; accelerated heavy ions and electrons were also detected. The major conclusion of this study is that despite several observed differences in the way that Venus and Mars interact with the solar wind, the dominant plasma features in the magnetic barrier region of Mars and the dayside mantle of Venus are very similar, indicating that probably the underlying physics is also similar.

Particle acceleration is a prominent feature of the geomagnetic storm, which is the prime dynamic process in Geospace – the near-Earth space environment. Magnetic storms have their origin in solar events, which are transient disturbances of the solar atmosphere and radiation that propagates as variations of the solar wind fields and particles through interplanetary space to the Earth's orbit. During magnetic storms, ions of both solar wind origin and terrestrial origin are accelerated and form an energetic ring current in the inner magnetosphere. This current has global geomagnetic effects, which have both physical and technical implications. Recently, it has been shown that large magnetic storms, which exhibit an unusually energized ionospheric plasma component, are closely associated with coronal mass ejections (CMEs). This implies a cause/effect chain connecting solar events through CMEs and the solar wind with the acceleration of terrestrial ion populations which eventually constitute the main source of global geomagnetic disturbances. Here we present spacecraft observations related to storm-time particle acceleration and assess the observations within the framework of causes and effects of solar-terrestrial relationships.

Solar Orbiter is scheduled to launch in January 2017, and will carry as part of its payload the Heavy Ion Sensor (HIS), one of the components of the Solar Wind Analyzer (SWA) instrument suite. Heavy ions of particular interest are Ne, Mg, Si, and S which have been difficult to measure in the past due to their similar mass per charge ratios in the solar wind. We have characterized the response of HIS to these species using a Monte Carlo simulation of the instrument. These simulations use a realistic count rate and account for lost energy and angular scattering of ions passing through a carbon foil, time-of-flight of the secondary electrons, and the pulse height defect within the solid-state detectors. Our results show that HIS is capable of resolving the masses and charge-states of solar wind ions, such as He, C, O, Ne, Mg, and Fe. Results also show that there is some overlap between S and Si, but it is likely that we will be able resolve these ions by integrating these measurements over longer time periods.

During the last decade, satellite observations in the nightside magnetosphere have confirmed the presence of energetic (>20 keV) ionospheric-origin ions in the near-Earth magnetotail. Observations also imply that the feeding of the equatorial magnetosphere with ions from the high-latitude ionosphere can be very fast and intense at times. In the present paper we use observations from the Combined Release and Radiation Effects Satellite (CRRES) to investigate the characteristics of ion energy density variations. Multispecies studies of the energy density give important clues on the coupling of the different plasma sources and their participation in the substorm energization. The measurements, coming from the Magnetospheric Ion Composition Spectrometer (MICS), confirm previous results obtained from the AMPTE/CCE-CHEM spectrometer, with regard to the timing of the high-latitude ionosphere response to the equatorial magnetosphere disturbances. The energy density profile of the ionospheric-origin O+ follows the intensity enhancements of the westward electrojet very closely in time, exhibiting a continuing increase, contrary to the behaviour of the other major ion species H+ and He++. This feature, which is consistent with statistical studies of AMPTE/CCE observations, points towards a fast activation of an extraction/acceleration mechanism which feeds the inner plasma sheet with ions of ionospheric origin during the substorm expansion.

The Magnetospheric Ion Composition Spectrometer onboard the CRRES spacecraft provided mass and charge state composition data for positive ions in the energy-per-charge range 10-425 keV/e. The CRRES data is compared to the AMPTE/CCE observations during both geomagnetically quiet and active periods. The CRRES average radial profiles of H+, He+, and He++ during quiet intervals are remarkably similar to those measured by CCE. The excess of ions measured by CRRES at L

An event of tailward flowing energetic (144–7959 keV) oxygen ion bursts was observed in the distant magnetotail (X=−63, Y=+7, Z=−3.8 RE) on February 13, 1994. The observations were made with the HEP-LD spectrometer on board the GEOTAIL spacecraft. The event was associated with magnetic field signatures characteristic of multiple flux ropes. During the event, which lasted from 1847 to 1907 UT, strong impulsive increases in the oxygen flux were observed. From 1846 to 1900 UT the proton counting rate also exhibited an increase, followed by a decrease until the end of the oxygen event. The oxygen flux was confined to a rather narrow range in polar and azimuthal angle (only 7–10% of 4π was occupied). This implies a streaming distribution or beam-like structure. Comparison of the particle flow angles with the polar and azimuthal angles of the magnetic field indicates that the ion beam may have been embedded in flux ropes, which may be connecting the polar ionosphere and the distant magnetotail. During the observed oxygen event the ratio is significantly higher than the ratios usually found in the center of the distant magnetotail. There is some evidence that the observed oxygen ions were more efficiently accelerated in this event than hydrogen and helium ions.

The CELIAS experiment on SOHO is designed to measure the mass, ionic charge and energy of the low and high speed solar wind, of suprathermal ions, and of low energy flare particles. Through analysis of the elemental and isotopic abundances, the ionic charge state, and the velocity distributions of ions originating in the solar atmosphere, the investigation focuses on the plasma processes on various temporal and spatial scales in the solar chromosphere, transition zone, and corona. CELIAS includes 3 mass- and charge-discriminating sensors based on the time-of-flight technique: CTOF for the elemental, charge and velocity distribution of the solar wind, MTOF for the elemental and isotopic composition of the solar wind, and STOF for the mass, charge and energy distribution of suprathermal ions. The instrument will provide detailed in situ diagnostics of the solar wind and of accelerated particles, which will complement the optical and spectroscopic investigations of the solar atmosphere on SOHO. CELIAS also contains a Solar Extreme Ultraviolet Monitor, SEM, which continously measures the EUV flux in a wide band of 17 – 70 nm, and a narrow band around the 30.4 nm He II line.

Mean density and temperature gradients of solar wind protons and α particles are derived from SWICS/Ulysses observations between 1.2 and 5.4 AU in the ecliptic plane during declining solar activity. All parameters are sorted in solar wind speed classes. The radial gradients show a similar behavior for both ion species. In the slow solar wind protons as well as α particles are found to expand adiabatically all the way out to many AUs, while in the fast wind ions evolve non-adiabatically and are heated by interplanetary sources. The α particle to proton temperature and density ratios are also determined. They do not show any clear radial dependence.

Recent observations on board the Ulysses spacecraft show the presence of high velocity “tails” in the proton distribution functions as well as in heavier ion velocity distributions such as alpha particles and oxygen ions. These tails are exponential in shape and extend up to 10 thermal velocities, or beyond. It is generally believed that shock drift acceleration is responsible for tail formation. However, it is shown here that right-hand polarized electromagnetic waves driven by thermal anisotropies, can also accelerate high velocity protons and heavier ions giving rise to tail formation. The particle velocity at which tail formation begins, depends on the value of the thermal anisotropy of the proton distribution function.

The high-speed solar wind streaming from the southern coronal hole was remarkably uniform and steady and was confined by a sharp boundary that extended to the corona and chromosphere. Charge state measurements indicate that the electron temperature in this coronal hole reached a maximum of about 1.5 million kelvin within 3 solar radii of the sun. This result, combined with the observed lack of depletion of heavy elements, suggests that an additional source of momentum is required to accelerate the polar wind.

Strofio is a scientific investigation to sample in-situ the neutral atoms in Mercury's exosphere. Strofio is based on a novel mass spectrograph that determines the particle mass-per-charge (m/q) by a time-of-flight (TOF) technique. This novel technique achieves a mass resolution (m/Δm) at mass 18 of >100, with a high sensitivity of 0.14 (counts/s)/(particles/cm3) and a mass of only 4kg. Strofio employs a rotating electric field to “stamp” the start time of the incoming ionized particles and a micro-channel plate (MCP) detector to record the stop time and position. This eliminates the need for foils or shutters, resulting in nearly 100% duty cycle and a low mass design. Strofio is funded by NASA to fly on the European Space Agency mission BepiColombo to the planet Mercury. It is part of the four instrument SERENA suite situated on the Mercury Planetary Orbiter (MPO), which will enter in a 400 × 1500km polar orbit. This paper describes the theory of operation, the instrument components, and focuses on the front end electronics and processing required to read and accumulate the particle data.

The instruments for the HEP (High Energy Particle) experiments of the GEOTAIL mission, launched in July 1992, consist of 5 spectrometers (LD, BD, MI-1, MI-2 and HI). The LD (Low energy particle Detector) and the BD (Burst Detector) are mainly used to measure electrons, protons, helium and oxygen ions which reflect plasma dynamics in the magnetotail region. On the other hand, MI-1, MI-2 (Medium energy Isotope telescope-1, -2) and HI (High energy Isotope telescope) are used to measure the isotope abundance of solar flare particles and cosmic ray particles which reflect physical conditions of interplanetary space and origin of these particles

[1] During Cassini's Earth swing-by in 1999, the Low-Energy Magnetospheric Measurement System (LEMMS) detected energetic particles at the distant dawn magnetosheath. LEMMS identified 9 electron bursts and continuous proton flux surges at least up to 100 keV at X = −72 Re to −102 Re during the southward turning of the interplanetary magnetic field. All bursts were anti-field-aligned and correlated with the Bz directions streaming away from the magnetosphere, indicating that they are originated in the magnetosphere. The different source locations of protons and electron bursts were suggested from the magnetic field direction during the flux enhancement owing to the high time resolution mode of LEMMS: electrons were from flank low-latitude boundary layer and protons were from wide and dispersed region in the magnetopause. Although the energy spectra of the particles in the magnetosheath were similar to that in the plasma sheet, the proton spectra showed a bend around 5 keV possibly due to scatterings and accelerations by large amplitude waves. Most of these proton spectra were well described by the kappa distributions. The fact that the electron bursts were identified only at limited locations suggested that the reconnection on the magnetopause was required at the source, while protons could leak out both from the magnetic reconnection and the continuous gradient drift with wave scatterings at the magnetopause. Within the short time snapshot of the magnetosheath, extremely active feature of the particle leakage throughout the magnetopause was revealed.

The evolution of the surfaces of bodies unprotected by either strong magnetic fields or thick atmospheres in the Solar System is caused by various processes, induced by photons, energetic ions and micrometeoroids. Among these processes, the continuous bombardment of the solar wind or energetic magnetospheric ions onto the bodies may significantly affect their surfaces, with implications for their evolution. Ion precipitation produces neutral atom releases into the exosphere through ion sputtering, with velocity distribution extending well above the particle escape limits. We refer to this component of the surface ejecta as sputtered high-energy atoms (SHEA). The use of ion sputtering emission for studying the interaction of exposed bodies (EB) with ion environments is described here. Remote sensing in SHEA in the vicinity of EB can provide mapping of the bodies exposed to ion sputtering action with temporal and mass resolution. This paper speculates on the possibility of performing remote sensing of exposed bodies using SHEA The evolution of the surfaces of bodies unprotected by either strong magnetic fields or thick atmospheres in the Solar System is caused by various processes, induced by photons, energetic ions and micrometeoroids. Among these processes, the continuous bombardment of the solar wind or energetic magnetospheric ions onto the bodies may significantly affect their surfaces, with implications for their evolution. Ion precipitation produces neutral atom releases into the exosphere through ion sputtering, with velocity distribution extending well above the particle escape limits. We refer to this component of the surface ejecta as sputtered high-energy atoms (SHEA). The use of ion sputtering emission for studying the interaction of exposed bodies (EB) with ion environments is described here. Remote sensing in SHEA in the vicinity of EB can provide mapping of the bodies exposed to ion sputtering action with temporal and mass resolution. This paper speculates on the possibility of performing remote sensing of exposed bodies using SHEA and suggests the need for quantitative results from laboratory simulations and molecular physic modeling in order to understand SHEA data from planetary missions. In the Appendix, referenced computer simulations using existing sputtering data are reviewed.

Purpose To evaluate sport professionals’ attitudes towards visual correction in sport. Method A questionnaire was handed out in schools, gyms, sports centres and universities, to coaches, physical education teachers and final year students of motor science. The questionnaire was given to one group of sport physicians prior to a 1-day scientific update course on the benefits of contact lenses (CLs) in sport. At the end of the course, certain questions from the questionnaire were given out again in order to evaluate the effect of the update on their opinions. Results A total of 245 questionnaires were collected. The interviewees stated that correcting a vision defect during sports practice was important, but their propensity to suggest CLs for sport, though still rather high in value, showed a statistically significant drop. This drop did not occur if the CLs were recommended for competitive sports. This trend remained unchanged if a specific judgement was requested for the adolescent category. The tendency to suggest CLs was higher in CL wearers as compared to non-wearers. The sport with the lowest recommendation of CLs was swimming. In the sample of sports physicians, a specific education on the subject of CLs increased the propensity to adopt CLs in sports. Conclusions The main “actors” in the sports sector regard correcting a vision defect during sport to be important. Nevertheless, their tendency to suggest CLs is significantly lower. Works that make these categories aware of the benefits of CLs in sport can certainly help to fill this gap.

A laboratory study was carried out to establish the relative importance of verbal and gestural behavior, as well as their interaction, for perceived social influence in more or less competitive small groups. Forty women (psychology students) participated in leaderless small group discussions of different sizes (fourmember and eight-member): at the end, each member rated the perceived influence in decision-making of every other member. Verbal dominance coding is based on traditional quantitative conversational dominance (number of talk turns). Gestural coding (conversational, ideational, object-adaptor, self-adaptor gestures) is based on classical gesture classifications. Beside a substantial effect of verbal dominance, the main result is that frequency of object-adaptors and conversational (only in large groups) and ideational (in both small and large groups) gestures increases perceived influence scores particularly when the verbal dominance of the speaker is low.

Energetic particles ( E p > 34 keV , 0 > 55 keV ), plasma ions (30 eV–6 keV) and magnetic fields have been observed onboard Phobos 2 during the approach phases of the spacecraft to the Phobos moon in February/March 1989. Water ions and protons escaping as neutral water molecules from Phobos and the Martian tail can generally be accelerated by the pickup process. The present study is concerned with the acceleration of particles at the evening side (α S/C = 90°) of the Martian bowshock, which escaped as neutrals, especially from the tail or at the front side of Phobos. Since the interplanetary magnetic field forms quasiperpendicular and quasiparallel shocks with the Martian bowshock, the shock drift and the Fermi acceleration process were considered as processes for a further acceleration. The observed particle fluxes are interpreted as protons of 34–200 keV and O + ions of 55–225 keV energy.

The location of the Martian magnetopause and that of the bow shock are studied on the basis of three-dimensional solar wind proton spectra measured by the TAUS spectrometer on board Phobos 2 in its 56 circular orbits. The clear and strong dependence of the areomagnetopause position on solar wind ram pressure was revealed, while the position of the bow shock was practically independent of this parameter. In the power law expression telling the dependence of the Martian magnetotail thickness D on the solar wind ram pressure: D∼(ϱυ²)−1/k, the power index turned out to be k∼5.9±0.5. The close coincidence of this index with k = 6 for a dipole geomagnetic field, and the large areomagnetotail thickness compared with the planetary diameter, suggest that an intrinsic dipole magnetic field is likely to be an important factor in the solar wind interaction with Mars. On the other hand, the relatively stable position of the subsolar point of the Martian magnetopause and unambiguous induction effects observed by the Phobos 2 MAGMA magnetic experiment in the magnetotail indicate the essential role of an induced magnetic field, too. The weak dependence of the terminator bow shock position on the solar wind ram pressure may be related to the relatively stable position of the subsolar magnetopause.

This is an exploratory study about factors affecting the usage of T-government services for payments through Digital Terrestrial Television (DTT). The widely known predicting model of ICT user acceptance UTAUT (Unified Theory of acceptance and Use of Technology) was applied to recognize those factors affecting usage, exploiting a pre-existing dataset coming from the Italian T-government project named "Services for citizens via DTT". The key moderators of the model (i.e. age, gender, experience, voluntariness of use) were not included in this analysis. The dataset came from a semi-structured questionnaire administered to 189 users. The results suggest that perceived security of payment, considered as a comprehensive sense of security of the user, can be a significant variable in determining the behavioral intention in payments through DTT. Moreover the qualitative results of this exploratory study indicate that the "idea" of bill payment through DTT is appreciated by users, but the actual procedure for service use can be still cumbersome, in comparison to the other channels used for payments (e.g. the post office or the Internet).

The ion composition in the Jovian environment was investigated with the Solar Wind Ion Composition Spectrometer on board Ulysses. A hot tenuous plasma was observed throughout the outer and middle magnetosphere. In some regions two thermally different components were identified. Oxygen and sulfur ions with several different charge states, from the volcanic satellite Io, make the largest contribution to the mass density of the hot plasma, even at high latitude. Solar wind particles were observed in all regions investigated. Ions from Jupiter's ionosphere were abundant in the middle magnetosphere, particularly in the high-latitude region on the dusk side, which was traversed for the first time.

Measurements of proton and heavy ion spectra by the TAUS spectrometer onboard the Phobos-2 orbiter provided the first in-situ experimental data on the problem of martian atmosphere dissipation. They are (i) the newly revealed escape of planetary heavy ions through the plasma sheet of the martian magnetotail, and (ii) the deceleration of solar wind protons upstream of the planetary bow shock possibly due to the presence of the hot oxygen corona of Mars.

Even though magnetic field and plasma in-situ measurements near Mars from the 1989 PHOBOS-2 project and from earlier missions are available, the existence of an Martian intrinsic magnetic field is still controversial. In this study we analyze data of the PHOBOS-2 magnetic field experiments MAGMA and FGMM and use the upstream solar wind parameters of the TAUS and ASPERA experiments. Different methods are used to investigate the influence of the interplanetary magnetic field (IMF) and of a possible weak intrinsic field on the solar wind interaction with Mars : The compressibility of plasma boundaries, the correlation between upstream IMF and tail properties and between magnetic field structures and planetary rotation. The study shows that the magnetic field in the tail is strongly correlated with the upstream IMF suggesting that the Martian magnetotail is induced, at least to a large extent. Compressibility studies reveal a weak dependence of the plasma boundaries on the solar wind dynamic pressure but the bow shock location appears to be not affected by the Martian longitude within the accuracy of our measurements. We conclude that an intrinsic planetary field, if it exists, does not play a major role in the interaction between the solar wind and Mars.

Electrostatic analyzers (ESA) have been used extensively for the characterization of plasmas in a variety of space environments. They vary in shape, geometry, and size and are adapted to the specific particle population to be measured and the configuration of the spacecraft. Their main function is to select the energy per charge of the particles within a passband. An energy-per-charge range larger than that of the passband can be sampled by varying the voltage difference between the ESA electrodes. The voltage sweep takes time and reduces the duty cycle for a particular energy-per-charge passband. Our design approach for an advanced mass and ionic charge composition experiment (AMICCE) has a novel electrostatic analyzer that essentially serves as a spectrograph and selects ions simultaneously over a broad range of energy-per-charge (E/q). Only three voltage settings are required to cover the entire range from approximately 10 to 270 keV/q, thus dramatically increasing the product of the geometric factor times the duty cycle when compared with other instruments. In this paper, we describe the AMICCE concept with particular emphasis on the prototype of the entrance system (ESA and collimator), which we designed, developed, and tested. We also present comparisons of the laboratory results with electrostatic simulations.

The social relations model (SRM; Kenny, 1994) explicitly proposes that leadership simultaneously operates at three levels of analysis: group, dyad, and individual (perceiver and target). With this model, researchers can empirically determine the amount of variance at each level as well as those factors that explain variance at these different levels. This chapter shows how the SRM can be used to address many theoretically important questions in the study of leadership and can be used to advance both the theory of and research in leadership. First, based on analysis of leadership ratings from seven studies, we find that there is substantial agreement (i.e., target variance) about who in the group is the leader and little or no reciprocity in the perceptions of leadership. We then consider correlations of leadership perceptions. In one analysis, we examine the correlations between task-oriented and socioemotional leadership. In another analysis, we examine the effect of gender and gender composition on the perception of leadership. We also explore how self-ratings of leadership differ from member perceptions of leadership. Finally, we discuss how the model can be estimated using conventional software.

SERENA (‘Search for Exospheric Refilling and Emitted Natural Abundances’) is an instrument package that will fly on board the BepiColombo Mercury Planetary Orbiter (MPO); it will investigate the Mercury’s complex particle environment that surrounds the planet. Such an environment is composed by thermal and directional neutral atoms (exosphere) originating via surface release and charge‐exchange processes, and by ionized particles originated through photo‐ionization and again by surface release processes. In order to accomplish the scientific goals, in‐situ analysis of the environmental elements is necessary, and for such a purpose the SERENA instrument shall include four units: two Neutral Particle Analyzers (ELENA and STROFIO) and two Ion Spectrometers (MIPA and PICAM). The scientific merit of SERENA is presented, and the basic characteristics of the four units are described, with a focus on novel technological aspects.

The IBEX-Lo sensor covers the low-energy heliospheric neutral atom spectrum from 0.01 to 2 keV. It shares significant energy overlap and an overall design philosophy with the IBEX-Hi sensor. Both sensors are large geometric factor, single pixel cameras that maximize the relatively weak heliospheric neutral signal while effectively eliminating ion, electron, and UV background sources. The IBEX-Lo sensor is divided into four major subsystems. The entrance subsystem includes an annular collimator that collimates neutrals to approximately 7°×7° in three 90° sectors and approximately 3.5°×3.5° in the fourth 90° sector (called the high angular resolution sector). A fraction of the interstellar neutrals and heliospheric neutrals that pass through the collimator are converted to negative ions in the ENA to ion conversion subsystem. The neutrals are converted on a high yield, inert, diamond-like carbon conversion surface. Negative ions from the conversion surface are accelerated into an electrostatic analyzer (ESA), which sets the energy passband for the sensor. Finally, negative ions exit the ESA, are post-accelerated to 16 kV, and then are analyzed in a time-of-flight (TOF) mass spectrometer. This triple-coincidence, TOF subsystem effectively rejects random background while maintaining high detection efficiency for negative ions. Mass analysis distinguishes heliospheric hydrogen from interstellar helium and oxygen. In normal sensor operations, eight energy steps are sampled on a 2-spin per energy step cadence so that the full energy range is covered in 16 spacecraft spins. Each year in the spring and fall, the sensor is operated in a special interstellar oxygen and helium mode during part of the spacecraft spin. In the spring, this mode includes electrostatic shutoff of the low resolution (7°×7°) quadrants of the collimator so that the interstellar neutrals are detected with 3.5°×3.5° angular resolution. These high angular resolution data are combined with star positions determined from a dedicated star sensor to measure the relative flow difference between filtered and unfiltered interstellar oxygen. At the end of 6 months of operation, full sky maps of heliospheric neutral hydrogen from 0.01 to 2 keV in 8 energy steps are accumulated. These data, similar sky maps from IBEX-Hi, and the first observations of interstellar neutral oxygen will answer the four key science questions of the IBEX mission.

Hall, Lord, and Foster (2009) have commented on whether variance partitioning in the social relations model would be the same in long-term groups and when groups have formal leaders. This reply follows their lead and speculates on how the variance partitioning would change. It considers the design and analysis issues in natural workgroups as well as the estimation of group effects.

Whether or not ICT represents the most important vehicle to transform the society seems to be out of discussion. The point of interest diverts from how people do really feel with these services and from the way they perceive the advantages as acceptable to improve the quality of life and work. It is matter of fact that the technical innovation is characterized by a certain risk, the problem of how to implement the technology for sure and, ahead of this phase, the problem of predicting its influence on the social, working and private life in view of the high costs effort to produce. This study applies a predictive model for the acceptance to a services integrated home environment properly set-up in a special laboratory. A class of users was selected from the employees of the company which hosted the trial in order to participate at the evaluation sessions. The tasks were designed to point out the main innovative features of the services presented. The questionnaires were suitably designed and submitted to collect the end-users opinions. Statistical analysis was carried out to assess the performance by the side of the real users and to predict their intentions of use. Finally both correlation and regression studies found out how the model predictors may respectively influence the acceptance of the ICT solutions proposed.

The ion-sputtering (IS) process is active in many planetary environments in the Solar System where plasma precipitates directly on the surface (for instance, Mercury, Moon, Europa). In particular, solar-wind sputtering is one of the most important agents for the surface erosion of a Near-Earth Object (NEO), acting together with other surface release processes, such as Photon Stimulated Desorption (PSD), Thermal Desorption (TD) and Micrometeoroid Impact Vaporization (MIV). The energy distribution of the IS-released neutrals peaks at a few eVs and extends up to hundreds of eVs. Since all other release processes produce particles of lower energies, the presence of neutral atoms in the energy range above 10 eV and below a few keVs (Sputtered High-Energy Atoms - SHEA) identifies the IS process. SHEA easily escape from the NEO, due to NEO's extremely weak gravity. Detection and analysis of SHEA will give important information on surface-loss processes as well as on surface elemental composition. The investigation of the active release processes, as a function of the external conditions and the NEO surface properties, is crucial for obtaining a clear view of the body's present loss rate as well as for getting clues on its evolution, which depends significantly on space weather. In this work, an attempt to analyze the processes that take place on the surface of these small airless bodies, as a result of their exposure to the space environment, has been realized. For this reason a new space weathering model (Space Weathering on NEO - SPAWN), is presented. Moreover, an instrument concept of a neutral-particle analyzer specifically designed for the measurement of neutral density and the detection of SHEA from a NEO is proposed, Comment: 36 pages