To improve the physical completeness of the data previously calculated (Schultz et al., 2017) to enable modeling of the effects of secondary electrons produced by energetic ion precipitation at Jupiter, we extend the treatment to include inelastic processes that occur simultaneously on the projectile (O q+ , q = 0-8)) and target (H 2). Here, processes considered in the previous work (single and double ionization, transfer ionization, double capture with subsequent autoionization, single and double stripping, single and double charge transfer, and target excitation) reflecting non-simultaneous projectile and target electron transitions, are replaced with processes that include both non-simultaneous and simultaneous electronic transitions on the target and projectile. These include, for example, single ionization, single ionization with simultaneous single projectile excitation, single ionization with double projectile excitation, single ionization with single projectile stripping, and single ionization with double projectile stripping. Using this expanded set of processes, we show, via Monte Carlo ion-transport simulation, that improved representation of the energy deposition, measured by the stopping power, is obtained as compared to accepted recommended values for intermediate energies (100-2000 keV/u) where the stopping power is largest, while maintaining the existing good agreement with these recommended values for low (∼10-100 keV/u) and high (≥2000 keV/u) energies. In addition, the ion-fraction distribution is altered by use of the improved data set. Both of these effects have implications for the energy deposition by oxygen ion precipitation in an H 2 atmosphere. Therefore, use of this expanded data set can provide a more physically realistic secondary-electron distribution, and consequently improved atmospheric reaction network, improved description of ion contribution to atmospheric currents, and therefore improved understanding of Jovian ionosphere-atmosphere coupling.
Postulating the existence of a finite-mass mediator of T,P-odd coupling between atomic electrons and nucleons we consider its effect on permanent electric dipole moment (EDM) of diamagnetic atoms. We present both numerical and analytical analysis for such mediator-induced EDMs and compare it with EDM results for the conventional contact interaction. Based on this analysis we derive limits on coupling strengths and carrier masses from experimental limits on EDM of 199 Hg atom.
Many attempts have been made to model X‐ray emission from both bremsstrahlung and ion precipitation into Jupiter's polar caps. Electron bremsstrahlung modeling has fallen short of producing the total overall power output observed by Earth‐orbit‐based X‐ray observatories. Heavy ion precipitation was able to reproduce strong X‐ray fluxes, but the proposed incident ion energies were very high ( >1 MeV per nucleon). Now with the Juno spacecraft at Jupiter, there have been many measurements of heavy ion populations above the polar cap with energies up to 300–400 keV per nucleon (keV/u), well below the ion energies required by earlier models. Recent work has provided a new outlook on how ion‐neutral collisions in the Jovian atmosphere are occurring, providing us with an entirely new set of impact cross sections. The model presented here simulates oxygen and sulfur precipitation, taking into account the new cross sections, every collision process, the measured ion fluxes above Jupiter's polar aurora, and synthetic X‐ray spectra. We predict X‐ray fluxes, efficiencies, and spectra for various initial ion energies considering opacity effects from two different atmospheres. We demonstrate that an in situ measured heavy ion flux above Jupiter's polar cap is capable of producing over 1 GW of X‐ray emission when some assumptions are made. Comparison of our approximated synthetic X‐ray spectrum produced from in situ particle data with a simultaneous X‐ray spectrum observed by XMM‐Newton shows good agreement for the oxygen part of the spectrum but not for the sulfur part.
To improve the physical completeness of the data previously calculated (Schultz et al., 2017) to enable modeling of the effects of secondary electrons produced by energetic ion precipitation at Jupiter, we extend the treatment to include inelastic processes that occur simultaneously on the projectile (O q+ , q = 0-8)) and target (H 2). Here, processes considered in the previous work (single and double ionization, transfer ionization, double capture with subsequent autoionization, single and double stripping, single and double charge transfer, and target excitation) reflecting non-simultaneous projectile and target electron transitions, are replaced with processes that include both non-simultaneous and simultaneous electronic transitions on the target and projectile. These include, for example, single ionization, single ionization with simultaneous single projectile excitation, single ionization with double projectile excitation, single ionization with single projectile stripping, and single ionization with double projectile stripping. Using this expanded set of processes, we show, via Monte Carlo ion-transport simulation, that improved representation of the energy deposition, measured by the stopping power, is obtained as compared to accepted recommended values for intermediate energies (100-2000 keV/u) where the stopping power is largest, while maintaining the existing good agreement with these recommended values for low (∼10-100 keV/u) and high (≥2000 keV/u) energies. In addition, the ion-fraction distribution is altered by use of the improved data set. Both of these effects have implications for the energy deposition by oxygen ion precipitation in an H 2 atmosphere. Therefore, use of this expanded data set can provide a more physically realistic secondary-electron distribution, and consequently improved atmospheric reaction network, improved description of ion contribution to atmospheric currents, and therefore improved understanding of Jovian ionosphere-atmosphere coupling.
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