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The Jovian system is very intriguing with extremely different particle sources. As the dominant source of particles to Jupiter's magnetosphere, Io is of particular importance. The JAXA Hisaki (SPRINT‐A) mission is providing insightful observations with regard to Io. In particular, its UV neutral oxygen line of sight observations provide the best glimpse so far of Jovian neutral particle populations. This is exciting in that for the first time, the neutral tori can be directly observed on time scales that constrain satellite sources. This data also sheds unprecedented insight into neutral torus distributions, which could subsequently provide essential information about the sources and mechanisms from Io. However, 3‐D modeling is also required to interpret the complex and dynamic observational geometries. Here, we present the first 3‐D distribution of the Io‐generated neutral oxygen torus using JAXA Hisaki neutral oxygen observations as modeling constraints to provide characterization of the Io magnetospheric source and the resulting neutral tori. Major findings of our research include: (a) the effective total original SO2 source rate from Io during a low activity period is ∼800 kg/s; (b) Io has two separate exospheric sources: O at ∼200 kg/s and SO2 at ∼400 kg/s; (c) particles escape from Io preferentially on the Jupiter upstream facing hemisphere; (d) the oxygen neutral torus populates the entire orbit and significantly dominates over the SO2, SO, and S neutral toroidal clouds; and (e) large ionization and dissociation rates limit the significant expansion of Io‐genic neutral particles in Jupiter's magnetosphere beyond ∼2 Rj from Io's orbit. Plain Language Summary: The Jovian system is very intriguing with extremely different particle sources. As the dominant source of particles to Jupiter's magnetosphere, Io is of particular importance. The JAXA Hisaki (SPRINT‐A) mission is providing insightful observations with regard to Io. This is exciting in that for the first time, the extended neutral particle distribution can be directly observed on time scales that constrain satellite sources. This data also sheds unprecedented insight into neutral particle distributions in Jupiter's magnetosphere, which could subsequently provide essential information about the sources and mechanisms from Io. However, 3‐D modeling is also required to interpret the complex and dynamic observational geometries. Here, we present the first 3‐D distribution of the Io‐generated neutral oxygen torus using JAXA Hisaki neutral oxygen observations as modeling constraints to provide characterization of the Io magnetospheric source and the resulting neutral tori. Major findings of our research include: Io has two separate exospheric sources: O at ∼200 kg/s and SO2 at ∼400 kg/s; particles escape from Io preferentially on the Jupiter upstream facing hemisphere; the oxygen neutral torus populates the entire orbit and significantly dominates over the SO2, SO, and S; and neutral particles from Io remain close to its orbit. Key Points: The first 3‐D distribution of the Io‐generated neutral oxygen torus using JAXA Hisaki neutral oxygen observations as modeling constraintsIo has two separate exospheric sources (preferentially escaping on the Jupiter facing hemisphere): O at ∼200 kg/s and SO2 at ∼400 kg/sThe oxygen neutral torus populates the entire orbit and significantly dominates over the SO2, SO, and S neutral toroidal clouds [ABSTRACT FROM AUTHOR]

In the Jovian magnetosphere, sulfur and oxygen ions supplied by the satellite Io are distributed in the so‐called Io plasma torus. The plasma torus is located in the inner area of the magnetosphere and the plasma in the torus corotates with the planet. The density and the temperature of the plasma in the torus have significant azimuthal variations. In this study, data from three‐year observations obtained by the Hisaki satellite, from December 2013 to August 2016, were used to investigate statistically the azimuthal variations and to find out whether the variations were influenced by the increase in neutral particles from Io. The azimuthal variation was obtained from a time series of sulfur ion line ratios, which were sensitive to the electron temperature and the sulfur ion mixing ratio S3+/S+. The major characteristics of the azimuthal variation in the plasma parameters were consistent with the dual hot electron model, proposed to explain previous observations. On the other hand, the Hisaki data showed that the peak System III longitude in the S3+/S+ ratio was located not only around 0°–90°, as in previous observations, but also around 180°–270°. The rotation period, the System IV periodicity, was sometimes close to the Jovian rotation period. Persistent input of energy to electrons in a limited longitude range of the torus is associated with the shortening of the System IV period. Key Points: Persistent azimuthal variations in the Io plasma torus were confirmed from three years of Hisaki observationsThe characteristics of the azimuthal variation were consistent with the dual hot electron model but different behaviors were also foundThe System IV period decreased 3 times. Two of these decreases were associated with increased volcanic activity on Io [ABSTRACT FROM AUTHOR]

The innermost Galilean satellite, Io, supplies a large amount of volcanic gasses to the Jovian magnetosphere. The fast rotation of Jupiter and the outward transport of ionized gasses are responsible for forming a huge and rotationally dominant magnetosphere. The plasma supply from the satellite has a key role in the characterization of the Jovian magnetosphere. In fact, significant variations of the plasma population in the inner magnetosphere caused by the volcanic eruptions in Io were found in early 2015, using a continuous data set of the Io plasma torus obtained from an extreme ultraviolet spectroscope onboard the Hisaki satellite. The time evolution of the Io plasma torus radial distribution showed that the outward transport of plasma through 8 RJ from Jupiter was enhanced for approximately 2 months (from the end of January to the beginning of April 2015). Intense short‐lived auroral brightenings––which represent transient energy releases in the outer part of the magnetosphere—occurred frequently during this period. The short‐lived auroral brightenings accompanied well‐defined sporadic enhancements of the ion brightness in the plasma torus, indicating a rapid inward transport of energy from the outer part of the magnetosphere and the resultant enhancement of hot electron population in the inner magnetosphere. This evidently shows that the change in a plasma source in the inner magnetosphere affects a large‐scale radial circulation of mass and energy in a rotationally dominant magnetosphere. Plain Language Summary: We present the first continuous and long‐term monitoring of both ultraviolet aurora activity and ionized gas around Jupiter obtained by the Earth‐orbiting spectroscope satellite, Hisaki. The innermost Galilean satellite, Io, is the volcanically most active body in our solar system. The volcanic gasses are ionized in the magnetosphere, the region manipulated by the planetary magnetic field, and obtain angular momentum from Jupiter's fast rotation through the magnetic field connecting with Jupiter. When Io's volcanic activity increased in early 2015, Hisaki observed that the Jovian magnetosphere was filled with iogenic ionized gasses for over 2 months and Jupiter's powerful auroral breakups occurred very frequently. This is contradictory to the terrestrial magnetosphere in which the aurora breakup occurs as a result of the solar wind‐energy penetration into the magnetosphere. Although Io occupies only a very small region in the vast Jovian magnetosphere, it releases significant amounts of material around the space near Jupiter, extracts energy from Jupiter's rotation, and affects activation of the powerful aurora of the giant planet. Key Points: Evolution of Io plasma torus radial distribution caused by volcanic eruptions in Io was observed in early 2015Outward plasma transport from the Io plasma torus through 8 RJ from Jupiter enhanced for approximately 2 monthsAn inner magnetosphere plasma source is shown to affect large‐scale mass/energy radial circulation in rotationally dominant magnetosphere [ABSTRACT FROM AUTHOR]

Single-event effects (SEE) evaluation of five different part types of next generation, commercial trench MOSFETs indicates large part-to-part variation in determining a safe operating area (SOA) for drain-source voltage ( \text V\mathrm { {DS}} ) following a test campaign that exposed >50 samples per part type to heavy ions. These results suggest a determination of a SOA using small sample sizes may fail to capture the full extent of the part-to-part variability. An example method is discussed for establishing a Safe Operating Area using a one-sided statistical tolerance limit based on the number of test samples. Burn-in is shown to be a critical factor in reducing part-to-part variation in part response. Implications for radiation qualification requirements are also explored. [ABSTRACT FROM PUBLISHER]

A study of proton-induced destructive SEE (DSEE) from Au-plated lid fission fragments has been expanded. Seventeen additional lid materials (Z =26–83) are studied. Lead (Pb) produced a higher sensitivity than seen in previous work with gold (Au), raising new concerns of SEE enhancement due to die-proximate Pb-based solder in flip-chip package designs. New analysis has allowed generalized RHA rules to be developed. [ABSTRACT FROM PUBLISHER]

We studied the electronic and nuclear dynamics of I-containing organic molecules induced by intense hard X-ray pulses at the XFEL facility SACLA in Japan. The interaction with the intense XFEL pulse causes absorption of multiple X-ray photons by the iodine atom, which results in the creation of many electronic vacancies (positive charges) via the sequential electronic relaxation in the iodine, followed by intramolecular charge redistribution. In a previous study we investigated the subsequent fragmentation by Coulomb explosion of the simplest I-substituted hydrocarbon, iodomethane (CH3I). We carried out three-dimensional momentum correlation measurements of the atomic ions created via Coulomb explosion of the molecule and found that a classical Coulomb explosion model including charge evolution (CCE-CE model), which accounts for the concerted dynamics of nuclear motion and charge creation/charge redistribution, reproduces well the observed momentum correlation maps of fragment ions emitted after XFEL irradiation. Then we extended the study to 5-iodouracil (C4H3IN2O2, 5-IU), which is a more complex molecule of biological relevance, and confirmed that, in both CH3I and 5-IU, the charge build-up takes about 10 fs, while the charge is redistributed among atoms within only a few fs. We also adopted a self-consistent charge density-functional based tight-binding (SCC-DFTB) method to treat the fragmentations of highly charged 5-IU ions created by XFEL pulses. Our SCC-DFTB modeling reproduces well the experimental and CCE-CE results. We have also investigated the influence of the nuclear dynamics on the charge redistribution (charge transfer) using nonadiabatic quantum-mechanical molecular dynamics (NAQMD) simulation. The time scale of the charge transfer from the iodine atomic site to the uracil ring induced by nuclear motion turned out to be only ∼5 fs, indicating that, besides the molecular Auger decay in which molecular orbitals delocalized over the iodine site and the uracil ring are involved, the nuclear dynamics also play a role for ultrafast charge redistribution. The present study illustrates that the CCE-CE model as well as the SCC-DFTB method can be used for reconstructing the positions of atoms in motion, in combination with the momentum correlation measurement of the atomic ions created via XFEL-induced Coulomb explosion of molecules. [ABSTRACT FROM AUTHOR]

Proton single event dielectric rupture was observed in Analog Devices OP470 devices only when the package included gold flashing facing the die on the inner surface of the metal lid. The supply voltage was also a factor. Analysis shows that proton on gold fission fragments have the linear energy transfer and range to cause this effect. The physics of proton on gold reactions and radiation hardness assurance implications are explored. [ABSTRACT FROM PUBLISHER]

Background Splenic vein ligation may result in sinistral (left-sided) portal hypertension and gastrointestinal haemorrhage. The aim of this study was to analyse the pathogenesis of sinistral portal hypertension following splenic vein ligation in pancreaticoduodenectomy. Methods Patients who underwent pancreaticoduodenectomy for pancreatic cancer between January 2005 and December 2012 were included in this retrospective study. The venous flow pattern from the spleen and splenic hypertrophy were examined after surgery. Results Of 103 patients who underwent pancreaticoduodenectomy with portal vein resection, 43 had splenic vein ligation. There were two predominant venous flow patterns from the spleen. In the varicose route (27 patients), flow from the spleen passed to colonic varices and/or other varicose veins. In the non-varicose route, flow from the spleen passed through a splenocolonic collateral (14 patients) or a spontaneous splenorenal shunt (2 patients). The varicose route was associated with significantly greater splenic hypertrophy than the non-varicose route (median splenic hypertrophy ratio 1·52 versus 0·94; P < 0·001). All patients with the varicose route had colonic varices, and none had a right colic marginal vein at the hepatic flexure. Conclusion Pancreaticoduodenectomy with splenic vein ligation may lead to sinistral portal hypertension. To avoid the development of varices, it is important to preserve the right colic marginal vein. Reconstruction of the splenic vein should be considered if the right colic marginal vein is divided. [ABSTRACT FROM AUTHOR]