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BepiColombo MPO and Mio spacecraft encounter the Mercury magnetosphere six times from 2021 to 2025 during the flyby maneuvers. Each flyby trajectory is unique and includes the magnetospheric regions that were not covered by MESSENGER. Mio/MGF magnetic field data were successfully retrieved during the Mercury flyby-2 in June 2022 and the data were calibrated for the scientific use. The MGF measurements show a short-time intense magnetic field depression in close proximity to the planet at local midnight, which is neither expected from the earlier observations (Mariner-10, MESSENGER) nor from the hybrid plasma simulations of the Mercury magnetosphere. Both time-dependent and time-independent scenarios are possible, including the occurrence of a transient event driven by sudden changes in the solar wind (e.g., pressure puls) or in the magnetosphere (e.g., magnetic reconnection) and the crossing of a localized current layer separating the dipolar field region from the stretched tail-like magnetic field region. While more dedicated analyses (wave analysis, variation analysis), combination with the other data (plasmas and imaging), and numerical simulations for different scenarios would improve the quality of scientific interpretation of the depression event, our study demonstrates the scientific potential of BepiColombo that it will detect various kinds of transient events and localized structures in Mercury’s magnetosphere already during the flyby maneuvers.

Mercury possesses a weak planetary dipole moment and is subject to a strong solar wind inflow. Thus, a small magnetosphere is formed. On the nightside, a neutral current sheet elongates the magnetic field lines to form a magnetotail. From hybrid simulations it is known that this current sheet reacts to changes in the interplanetary magnetic field (IMF). In order to understand the magnetospheric reaction to changes in the solar wind, it is essential to further assess the neutral current sheet movements. The strongly radial IMF at Mercury facilitates magnetopause reconnection in high latitudes which decreases the magnetic pressure in one of the magnetospheric lobes depending on the radial IMF polarity. This produces a northward (or southward) shift of the neutral sheet. Here, we present statistical results from in-situ MESSENGER magnetic field data analysis on the IMF direction as well as the neutral sheet displacement. MESSENGER was a single probe in orbit around Mercury and, as such, it was blind to the solar wind state after having entered the bow shock. Thus, we need to estimate the current IMF radial polarity for the time frame with the probe located inside the magnetosphere. For this, we evaluate different interpolation methods with an adapted bootstrap analysis method on data taken within the upstream solar wind at Mercury. Eventually, the outcome of the statistical analysis on the neutral sheet displacement is compared to the results from hybrid simulations done in the past.

Magnetic holes are significant depressions of the interplanetary magnetic field (IMF) that can be found embedded in the solar wind everywhere within the heliosphere. They resemble mirror mode magnetic structures that form as a response to excess perpendicular temperatures. Magnetic holes situated at IMF discontinuities (current sheets) may also be the result of reconnection. Magnetic holes occur more often under fast solar wind conditions, and their scale sizes are known to be on the order of thousands to tens of thousands of km, determined essentially from temporal width and plasma velocity observations. So far, the scale sizes have only been estimated for the directions parallel to the respective solar wind plasma flows. In this study, we attempt to calculate the first distributions of the scale sizes for the orthogonal, flow-perpendicular directions. Therefore, we use multi-point observations of magnetic holes by the ARTEMIS spacecraft in lunar orbit. The method we use has been previously applied to plasma jets present in the magnetosheath of Earth. The knowledge of the flow-perpendicular scale sizes is important to assess the holes’ impact on planetary magnetospheres and cometary environments.

A high-precision model of steady-state plasma flow and magnetic field in the planetary magnetosheath region is proposed by introducing the concept of conformal mapping and transforming the Kobel-Flueckiger scalar potential (the exact solution of Laplace equation) from the parabolic boundaries (bow shock and magnetopause) into arbitrary shape of boundaries. While the statistically-confirmed bow shock and magnetopause models can often be extended to the complex plane by analytic contiuation, construction of conformal mapping in a general magnetosheath case turns out be a mathematical challenge. The reason for this is that the analytic continuation of the bow shock shape does not necessarily meet the analytic contination of the magnetopause shape in general. We overcome this problem and construct a numerical conformal mapping method for the magnetosheath with arbitrary bow shock and magnetopause shapes by (1) modeling shell-like envelopes that smoothly change vary between the two boundaries (the v-variables), (2) imposing the orthogonality condition to find normal directions to the envelopes (the u-variables), and (3) applying the u and v variables to the Kobel-Flueckiger potential. Our conformal mapping method serves as a reference model of magnetosheath, which is numerically inexpensive and is easily implemented. Analysis of in-situ measurement data and numerical simulations of the planetary magnetosheath region will significantly benefit from the conformal mapping method. Moreover, our method can be used to derive the upstream conditions (flow speed and magnetic field) using the magnetosheath data.

The Kelvin-Helmholtz (KH) instability is a shear-driven instability commonly observed at the Earth’s magnetopause under different solar wind conditions. The evolution of the KH instability is characterised by the nonlinear coupling of different modes, which tend to generate smaller and smaller vortices along the shear layer. Such a process leads to the conversion of energy due to the large-scale motion of the shear flow into heat contributing to the local heating and the generation of a turbulent environment. On the other hand, it allows the entry of the dense and cold solar wind plasma into the tenuous and hot magnetosphere, thus favoring the mixing of these two different regions.In this context, we introduce a new quantity, the so-called mixing parameter, which can identify the vortex boundaries and distinguish among different types of KH structures crossed by the spacecraft. The mixing parameter exploits the well distinct particle energies which characterise the magnetosphere and magnetosheath plasmas by using only single-spacecraft measurements [1]. The mixing parameter is therefore used to conduct a statistical analysis of the evolution of KH structures observed by the Magnetospheric Multiscale mission in the near Earth’s environment for two specific interplanetary magnetic field configurations: northward and southward. Moreover, in situ measurements are compared with kinetic KH instability simulations modeling realistic conditions observed by the satellites. The good agreement between synthetic data and in situ observations further strengthen our interpretation of the mixing parameter features and results. [1] Settino, A., et al. (2022) Journal of Geophysical Research: Space Physics, 127, e2021JA029758.

The study of the structure and dynamics of Mercury’s magnetosphere is still an open research topic in space physics. Upon other mission objectives, the on-going BepiColombo mission will study the plasma environment around Mercury with multiple field and particle instruments. One of them is the Planetary Ion Camera (PICAM). It is an ion spectrometer designed to measure low-energy pick-up heavy ions (e.g. sodium). Due to ejection mechanisms and the solar wind influence, these particles are emitted from the surface of Mercury. The resulting electric currents, like perpendicular and field-aligned currents need to be studied to understand the global magnetospheric current structure as well as its variability due to the solar wind conditions.In this study, numerical simulations with a global 3D hybrid model are used to investigate and forecast the typical ion profile with energies up to 5 keV during the BepiColombo flyby trajectories in the years 2021-2025. Magnetotail reconnection causes the acceleration of particles towards the planet. The resulting field-aligned current is studied to about 3 RM in tailward direction. The simulations are conducted with the AIKEF (Adaptive Ion Kinetic Electron Fluid) model. The kinetic treatments of the ions will enable to directly compare magnetospheric particle species model results with PICAM observations.

We present the potential mapping method which is a model of steady-state flow velocity and magnetic field in the empirical magnetosheath domain. The method makes use of a coordinate transformation from the empirical magnetosheath domain into the parabolic magnetosheath domain, and evaluate a set of the shell variable and the connector variable to utilize the solution of Laplace equation obtained for the parabolic magnetosheath domain. Our model uses two invariants of transformation: the zenith angle in the magnetosheath and the ratio of the distance to the magnetopause to the thickness of magnetosheath along the magnetopause-normal direction. The plasma flow and magnetic field can be determined as a function of the upstream condition (flow velocity or magnetic field) in a wider range of zenith angle. The potential mapping method is computationally inexpensive by using the analytic expression as much as possible, is applicable to the planetary magnetosheath domains.

Based on the magnetohydrodynamic (MHD) shock jump condition (Rankine-Hugoniot relation), we develop a tool to determine the relationship between the density jump, Alfven Mach number and the solar wind plasma beta directly from magnetic field observations across the shock. The presented method is a useful tool to characterize the bow shock around planets, where plasma data are often limited or even not available. In particular in view of the ongoing Bepi-Colombo mission the tool can help to diagnose and characterize the bow shock during the planetary flybys.

Post-flame sulfation of gaseous sodium hydroxide (NaOH) and sodium chloride (NaCl) was investigated with optical in situ measurements at 850 to 1475 °C. A multi-jet burner was used to generate well-controlled combustion environments. The multi-jet burner also enabled the separate feeding of the sodium species and SO2 to the combustion environment where the sulfation reactions occurred. Concentrations of NaOH(g) and NaCl(g) were measured in the product gas using broadband UV absorption spectroscopy to follow the degree of sulfation. At 1475 and 1275 °C almost no sulfation occurred with an initial NaOH(g) concentration of 20 ppm and SO2 concentrations between 0 and 150 ppm. At 985 °C, the NaOH(g) concentration decreased to less than 5 ppm with SO2 concentrations above 50 ppm and at 850 °C almost all NaOH(g) was sulfated under these conditions. The experimental results for the gas-phase sulfation of NaOH were compared to previous results for the sulfation of KOH under the same conditions and the results were shown to be similar for NaOH and KOH under these conditions. Sulfation of NaOH(g) generally occurred to a more significant extent than the sulfation of NaCl(g). At 1115 to 1475 °C, no sulfation of NaCl(g) was observed. At the lowest investigated temperature, 850 °C, the NaCl(g) concentration decreased from 20 ppm to 12 ppm after the addition of 150 ppm SO2. Chemical equilibrium calculations and kinetic modeling using an updated kinetic model for the detailed Na-Cl-S chemistry were compared to the experimental results. Above 1100 °C, the system can be described by chemical equilibrium, implying that equilibrium is reached in less than 100 ms. At temperatures below 1100 °C, the measured concentration indicated kinetic control. Under these conditions, the kinetic model was in good agreement with the experimental results for NaOH(g) but over-predicted the sulfation of NaCl(g). The combined experimental data, chemical equilibrium calculations and kinetic modeling of the present study support that sulfation of alkali species can occur in the gas phase through homogeneous reactions.

This paper presents an illustrated model to explain digitalisation in industry in a holistic, non-technological way. It reflects the dimensions of the product lifecycle and the supply chain. More specifically, it discusses the interaction between customer, product, production, and suppliers along a product’s life and how digitalisation supports these interactions. Particular attention is given to the transition from type to its product instances. Especially in the case of complex products, mastering this transition plays a key role in understanding digitalisation requirements. Reclining the concept of type and instance, different element of the digital twin, as digital master and the different shadows, are classified. Developed initially to structure a course in an engineering master’s program, the model has evolved to be used in different courses and currently supports consulting and applied research projects to orchestrate digitalisation initiatives in the industry.

Out of the two Venus flybys that BepiColombo uses as a gravity assist manoeuvre to finally arrive at Mercury, the first took place on 15 October 2020. After passing the bow shock, the spacecraft travelled along the induced magnetotail, crossing it mainly in the YVSO direction. In this paper, the BepiColombo Mercury Planetary Orbiter Magnetometer (MPO-MAG) data are discussed, with support from three other plasma instruments: the Planetary Ion Camera (SERENA-PICAM) of the SERENA suite, the Mercury Electron Analyser (MEA), and the BepiColombo Radiation Monitor (BERM). Behind the bow shock crossing, the magnetic field showed a draping pattern consistent with field lines connected to the interplanetary magnetic field wrapping around the planet. This flyby showed a highly active magnetotail, with e.g. strong flapping motions at a period of ∼7 min. This activity was driven by solar wind conditions. Just before this flyby, Venus's induced magnetosphere was impacted by a stealth coronal mass ejection, of which the trailing side was still interacting with it during the flyby. This flyby is a unique opportunity to study the full length and structure of the induced magnetotail of Venus, indicating that the tail was most likely still present at about 48 Venus radii.

Magnetopause model is presented as a conformal mapping in the complex plane. The model is an analytic continuation of the power-law damped (or asymptotically elongated) parabolic shape constructed by Shue et al. (J. Geophys. Res., 102, 9497, 1997). The analytic expression of the magnetopause using the conformal mapping opens the door to properly map the magnetopause and magnetosheath coordinates from one model to another.

Biomass can be used to generate heat, power, or biofuels in thermal conversion processes such as combustion, gasification and pyrolysis. However, some types of biomass contain high levels of phosphorus, which can be released to the gas phase and cause operational or environmental problems. The mechanism(s) responsible for phosphorus release has not been convincingly established. Understanding the high-temperature phosphorus chemistry is also important in order to enable efficient recovery of phosphorus in residues from thermal conversion of biomass. In this work, the release of phosphorus from wheat bran char and sunflower seed char in different gas environments (100 % N2, 1–20 % O2, and 10 % CO2) and temperatures (900–1100 °C) was studied. The chars were converted in a horizontal tube reactor and characterized using ICP-OES, XRD, SEM-EDS, and 31P NMR. The release of ash-forming elements was determined using ICP-OES analysis of the char and sample residues, whereas the release of carbon was determined using CO and CO2 gas analysis. In both chars, phosphorus was present primarily together with potassium and magnesium, mainly as pyrophosphates in the wheat bran char, and largely as orthophosphates in the sunflower seed char. For wheat bran char, the release of phosphorus increased from 27 % at 900 °C to 71 % at 1100 °C in N2, whereas the release was at least 20 % lower in the oxidizing atmospheres (1–20 % O2, or 10 % CO2). The sunflower seed char reached a maximum release of 55 % at 1100 °C in N2. For wheat bran char, the molar ratio of released carbon/phosphorus was close to 2.5, which fits well with the theoretical value for carbothermic reduction of phosphates (P2O5(s, l) + 5C(s) → P2(g) + 5CO(g)). At 1100 °C, in N2, the release of phosphorus, potassium and sodium occurred mainly during the first 10 min. It was shown that KMgPO4, used as a model compound, could be reduced by carbon starting from 950 °C, but that some of the phosphorus remained in the condensed phase. The work provides a better understanding of phosphorus release and presents evidence showing that carbothermic reduction reactions can be an important phosphorus release mechanism for seed- and grain-based biomass char.

The magnetosheath is defined as the plasma region between the bow shock, where the super-magnetosonic solar wind plasma is decelerated and heated, and the outer boundary of the intrinsic planetary magnetic field, the so-called magnetopause. Based on the Soucek–Escoubet magnetosheath flow model at the Earth, we present an analytical magnetosheath plasma flow model around Mercury. The model can be used to estimate the plasma flow magnitude and direction at any given point in the magnetosheath exclusively on the basis of the plasma parameters of the upstream solar wind. The model serves as a useful tool to trace the magnetosheath plasma along the streamline both in a forward sense (away from the shock) and a backward sense (toward the shock), offering the opportunity of studying the growth or damping rate of a particular wave mode or evolution of turbulence energy spectra along the streamline in view of upcoming arrival of BepiColombo at Mercury.

Fluxgate magnetometers are widely used for in-situ magnetic field measurements in the context of geophysical and solar system studies. Like in most of experimental studies, magnetic field measurements using the fluxgate magnetometers are constrained to the associated uncertainties. To evaluate the performance of magnetometers, the measurement uncertainties of calibrated magnetic field data are quantitatively studied for a spinning spacecraft. The uncertainties are derived analytically by perturbing the calibration procedure, and are simplified into the first-order expression including the offset errors and the coupling of calibration parameter errors with the ambient magnetic field. The error study shows how the uncertainty sources combine through the calibration process. The final error depends on the ambient environment such as the magnitude of magnetic field relative to the offset error and the angle of magnetic field to the spacecraft spin axis are important factors. The offset uncertainties are the major factor in a low-field environment, while the angle uncertainties (rotation angle in the spin plane, sensor non-orthogonality, and sensor misalignment to the spacecraft reference directions) become more important in a high-field environment in a proportional way to the magnetic field. The error formulas serve as a useful tool in designing high-precision magnetometers in future spacecraft missions as well as in data analysis methods in geophysical and solar system science.

We have investigated how CO2 and H2O influence NO release rates during char oxidation of biomass. In addition, the role of catalytic elements in these processes has been studied. NO release rates w...

The magnetosheath is defined as the plasma region between the bow shock, where the super-magnetosonic solar wind plasma is decelerated and heated, and the outer boundary of the intrinsic planetary magnetic field, the so-called magnetopause. Recently we presented an analytical magnetosheath plasma flow model around Mercury, which can be used to estimate the plasma flow magnitude and direction at any given point in the magnetosheath exclusively on the basis of the plasma parameters of the upstream solar wind. However, this model assumes a constant plasma density and velocity along the flowlines. Here we present a more sophisticated model were we take hydrodynamic effects into account, to also obtain the density and velocity change along the flowline. The model serves as a useful tool to trace the magnetosheath plasma along the streamline both in a forward sense (away from the shock) and a backward sense (toward the shock), offering the opportunity of studying the growth or damping rate of a particular wave mode or evolution of turbulence energy spectra along the streamline in view of upcoming arrival of BepiColombo at Mercury.

The mass and energy transfer across Earth’s magnetopause is caused by a variety of different plasma processes. One of these processes is the Kelvin-Helmholtz instability (KHI), excited by the velocity shear between the fast-flowing magnetosheath plasma and the relatively stagnant magnetosphere. It has been frequently observed during periods of northward interplanetary magnetic field (IMF), however much less is known about its behaviour during southward IMF conditions.We present the first Magnetospheric Multiscale (MMS) observations of KH waves and vortices at the dusk-flank magnetopause during southward IMF conditions on September 23, 2017. The instability criterion for the KHI was fulfilled during this event. The boundary normal vectors, obtained by using multi-point methods, are consistent with the predicted structures of the KH waves. We further performed a series of realistic 2D and 3D fully kinetic PIC simulations based on the plasma parameters observed during this MMS event. A comparison to results from these simulations demonstrated quantitative consistencies with the MMS data in many aspects such as the flow and total pressure variations in the KH waves, and the signatures of the non-linearly rolled up KH vortices including the Low Density Faster Than Sheath (LDFTS) plasma.The simulations further showed that secondary instabilities are excited at the edges of the primary KHI. The Rayleigh-Taylor instability (RTI) can lead to the penetration of high-density arms into the magnetospheric side and disturb the structures of the vortex layer, leading to irregular variations of the surface waves. This can be an important factor in explaining the lower observational probability of KH waves during southward IMF than northward IMF. In the non-linear growth stage of the primary KHI, the lower-hybrid drift instability (LHDI) is excited at the vortex edges leading to efficient plasma mixing across the magnetopause.The high-time resolution of MMS measurements demonstrated the occurrence of kinetic-scale plasma waves mainly on the low-density side of the edges of the KH waves. Given quantitative consistencies with the simulations, these waves can be interpreted as being generated by the LHDI. These observed waves form due to the strong density gradient between the two sides of the boundary layer and can lead to a flattening of the edge layers.In this presentation, we will show the consistencies between MMS observations and 2D and 3D simulation runs focusing on the large-scale surface waves (KHI, RTI) and the small-scale fluctuations (LHDI) and outline the multi-scale properties of the observed KH waves during southward IMF.

The Dipolarization Front (DF), which is a sharp increase of the northward magnetic field component, accompanied by fast earthward-moving plasma flows, is a well known phenomenon in the Earth's Magnetotail. Plasma characteristics also change at the front, from colder and denser ahead of the front to a hotter and more diluted plasma at the trailing side. The DF is therefore considered to be the boundary between ambient plasma and the hotter reconnection outflow jets. The DF can be the host of several energy conversion processes between plasma particles and waves e.g. due to various instabilities. A recent statistical study by Hosner et al. PoP 2022 showed that all of the studied DFs are accompanied by enhanced wave activity around the lower hybrid frequency, suggesting the high occurrence of the Lower-Hybrid Drift instability (LHDI) at DFs. In the present study we investigate the evolution of the energy conversion process in a flux rope type DF, for which an electron-diffusion region was reported (Marshall et al. JGR 2020). We first examine the wave characteristics and LHDI signatures to compare and to contrast flux rope and non-flux rope type DFs. Secondly, we apply a magnetic field reconstruction technique (Denton et al. JGR 2020) to this event using MMS data, to reconstruct the changes of the local magnetic field structures of the flux rope and temporal/spatial evolution of the energy conversion processes within the DF.

Neoadjuvant chemotherapy has become a powerful tool to convert borderline resectable (BRPC) and locally advanced pancreatic cancers (LAPC) into a resectable scenario. However, data analyzing the optimal type of therapy are scarce. In the present multicenter retrospective study, we evaluated the influence of FOLFIRINOX (FFX) and gemcitabine (GEM)-based neoadjuvant therapy on patient prognosis.Data on 239 patients from 7 centers across Europe was gathered using an online database. Patients having received their first cycle of chemotherapy for BRPC/LAPC before 06/2017, with a minimum follow-up of 12 months, were included in the intention-to-treat analysis.Patients treated with neoadjuvant FFX (n = 135) or gemcitabine + nab-paclitaxel (GNP) (n = 38) had significantly improved radiological response according to RECIST criteria as compared to single-agent GEM (n = 16), with a partial/complete response of 59.3%, 55.3% and 6.25% respectively (p = 0.001). Treatment with FFX (n = 135) and GNP (n = 38) resulted in higher resection rates compared to GEM (73.3%, 81.6% and 43.8%; p = 0.01 and p = 0.005). Regardless of regimen, patients who were resected had significantly prolonged overall survival compared to non-resected patients (p 0.01). Complete pathological responses (ypT0 ypN0) were predominantly observed with FFX (p = 0.01). Adjuvant GNP in addition to successful neoadjuvant therapy and surgery resulted in a trend towards improved median survival as compared to postoperative observation (47.0 vs. 30.1 months, p = 0.06).Representing one of the largest studies published so far, our results reveal that patients with BRPC/LAPC should be offered either FFX or GNP to improve chances of resection and with this also survival.