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The ubiquity of sulfur ions within the Jovian magnetosphere has led to suggestions that the implantation of these ions into the surface of Europa may lead to the formation of SO2. However, previous studies on the implantation of sulfur ions into H2O ice (the dominant species on the Europan surface) have failed to detect SO2formation. Other studies concerned with similar implantations into CO2ice, which is also known to exist on Europa, have offered seemingly conflicting results. In this letter, we describe the results of a study on the implantation of 290 keV S+ions into condensed CO2at 20 and 70 K. Our results demonstrate that SO2is observed after implantation at 20 K, but not at the Europa‐relevant temperature of 70 K. We conclude that this process is likely not a reasonable mechanism for SO2formation on Europa, and that other mechanisms should be explored instead. SO2ice is known to exist at the surface of one of Jupiter's moons; Europa. However, the method by which this ice forms is still uncertain. Due to the orbit of Europa being within the giant magnetosphere of Jupiter, it has been proposed that sulfur ions within the magnetosphere could implant into the cold surface ices on Europa and subsequently react to form SO2. However, laboratory experiments looking into the implantation of such ions into H2O ice (the dominant ice on Europa's surface) and CO2ice have either failed to yield SO2or have provided inconclusive results. We have therefore performed an experiment in which we have implanted high‐energy sulfur ions into CO2ice at two temperatures. Our results indicate that such implantations are unlikely to be the mechanism by which the SO2on Europa is formed, and that other chemical processes should be considered instead. Sulfur ions were implanted into CO2ices at 20 and 70 K to simulate Jovian magnetospheric radiation chemistry at the surface of EuropaSO2was observed to be among the radiolytic products at 20 K, but not at the more Europa‐relevant temperature of 70 KAlternative explanations for the formation of SO2on the surface of Europa should be considered Sulfur ions were implanted into CO2ices at 20 and 70 K to simulate Jovian magnetospheric radiation chemistry at the surface of Europa SO2was observed to be among the radiolytic products at 20 K, but not at the more Europa‐relevant temperature of 70 K Alternative explanations for the formation of SO2on the surface of Europa should be considered

The measurement of the strong-interaction effects in pionic hydrogen gives access to fundamental properties of the pion–nucleon interaction. Methods developed within the framework of Heavy-Baryon Chiral Perturbation Theory allow calculations with an accuracy of a few per cent, which should be tested by experiment. Techniques advanced for recent experiments on the precision spectroscopy of X-rays from antiprotonic and pionic atoms will be used in a new series of measurements for pionic hydrogen. The aim is to achieve finally an accuracy of 0.2% for the hadronic shift ∈1sand most important of about 1% for the broadening Γ1s. An essential part of the experimental program is an improved understanding of the atomic cascade. At first, the value of ∈1shas to be proven not to be influenced by molecular formation. Secondly, a more accurate determination of Γ1srequires a detailed study of Coulomb deexcitation.

We placed an axially movable electrode into the plasma chamber of the 18 GHz RIKEN ECR ion source in order to produce higher intensity of multiply charged ions and to study how the electrode effects the highly charged ion (HCI) production. We found that the effect of the electrode strongly depends on the local plasma parameters, mainly on the electrode initial floating potential. At lower floating potential, we need to increase the plasma density by means of biasing the electrode and injecting electrons into the plasma. The electrode operates as an electron source (Electron Donor or ED mode). At higher floating potential, the electrode works by changing the plasma potential. The best result is obtained when the electrode remains at floating potential (Plasma Tuner or PT mode). These two modes were checked and successfully found both in the continuous and in the pulsed mode operation. In both (ED and PT) modes, we generated higher HCI currents than without the electrode. In the PT mode, we successfully obtained 300 eμA of Ar11+at 15 kV extraction voltage.