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| openaire: EC/H2020/633053/EU//UFOS Funding Information: Acknowledgements. This work benefited from the Hinode sunspot database at MPS, created by Gautam Narayan. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 695075) and has been supported by the BK21 plus program through the National Research Foundation (NRF) funded by the Ministry of Education of Korea. Hinode is a Japanese mission developed and launched by ISAS/JAXA, collaborating with NAOJ as a domestic partner, NASA and STFC (UK) as international partners. Scientific operation of the Hinode mission is conducted by the Hinode science team organized at ISAS/JAXA. This team mainly consists of scientists from institutes in the partner countries. Support for the post-launch operation is provided by JAXA and NAOJ (Japan), STFC (UK), NASA, ESA, and NSC (Norway). Publisher Copyright: © B. Löptien et al. 2021. ; Context. It is unclear why there is a rather sharp boundary in sunspots between the umbra and the penumbra. Both regions exhibit magnetoconvection, which manifests in penumbral filaments in the penumbra and in umbral dots in the umbra. Aims. Here we compare the physical properties of umbral dots and penumbral filaments. Our goal is to understand how the properties of these convective features change across the boundary between the umbra and the penumbra and how this is related to the rapid increase in brightness at the umbra-penumbra boundary. Methods. We derived ensemble averages of the physical properties of different types of convective features based on observations of two sunspots with Hinode. Results. There are strong similarities between the convective features in the outer parts of the umbra and the ones in the penumbra, with most physical parameters being smooth and continuous functions of the length of the features. Conclusions. Our results indicate that the transition in brightness from the umbra to the penumbra is solely caused by an increased effectiveness of magnetoconvection within individual convective cells. There is no significant difference in the number density of convective elements between the outer umbra and the inner penumbra. Penumbral filaments exhibit a larger area and a higher brightness compared to umbral dots. It is still unclear how exactly the underlying magnetic field causes the increase in the size and brightness of convective features in the penumbra. ; Peer reviewed

| openaire: EC/H2020/818665/EU//UniSDyn Funding Information: Acknowledgements. MJK acknowledges the support of the Academy of Finland ReSoLVE Centre of Excellence (grant No. 307411). AP was funded by the International Max Planck Research School for Solar System Science at the University of Göttingen. This project has received funding from the European Research Council under the European Union's Horizon 2020 research and innovation programme (project "UniSDyn", grant agreement n:o 818665). SOLIS data used here are produced cooperatively by NSF/NSO and NASA/LWS. Publisher Copyright: © A. P. Prabhu et al. 2021. ; Context. Obtaining observational constraints on the role of turbulent effects for the solar dynamo is a difficult, yet crucial, task. Without such knowledge, the full picture of the operation mechanism of the solar dynamo cannot be formed. Aims. The magnetic helicity spectrum provides important information about the α effect. Here we demonstrate a formalism in spherical geometry to infer magnetic helicity spectra directly from observations of the magnetic field, taking into account the sign change of magnetic helicity across the Sun's equator. Methods. Using an angular correlation function of the magnetic field, we develop a method to infer spectra for magnetic energy and helicity. The retrieval of the latter relies on a fundamental definition of helicity in terms of linkage of magnetic flux. We apply the two-scale approach, previously used in Cartesian geometry, to spherical geometry for systems where a sign reversal of helicity is expected across the equator on both small and large scales. Results. We test the method by applying it to an analytical model of a fully helical field, and to magneto-hydrodynamic simulations of a turbulent dynamo. The helicity spectra computed from the vector potential available in the models are in excellent agreement with the spectra computed solely from the magnetic field using our method. In a next test, we use our method to obtain the helicity spectrum from a synoptic magnetic field map corresponding to a Carrington rotation. We observe clear signs of a bihelical spectrum of magnetic helicity, which is in complete accordance to the previously reported spectra in literature from the same map. Conclusions. Our formalism makes it possible to infer magnetic helicity in spherical geometry, without the necessity of computing the magnetic vector potential. It has many applications in solar and stellar observations, but can also be used to analyse global magnetoconvection models of stars and to compare them with observations. ; Peer reviewed

For the purpose of Technology Forecast 2021 five reports from the German Fraunhofer Institute were chosen by FMV (and SwAF) and given to Systems Science for Defence and Security Division to analyse and assess within the timeframe up to 2040. The following research reports were reviewed by the working group at SEDU: · Adversarial Machine Learning · High Entropy Ceramics · Large Unmanned Underwater Vehicles · Living Sensors · Machine Learning in Materials Development The aim of the Technology Forecast seminars and the finished product, this report, is to assess the potential military utility of the reviewed technologies and how they may contribute to the Swedish Armed Forces' operational capabilities based on the presented concept(s) and scenario(s). The military utility is categorised by one of four assessments: Significant, Moderate, Negligible or Uncertain. The following technologies were assessed to potentially have significant military utility: · High Entropy Ceramics · Machine Learning in Materials Development · Adversarial Machine Learning The following technology was assessed to potentially have moderate military utility: · Large Unmanned Underwater Vehicles The following technology was assessed to have uncertain military utility: · Living Sensors ; Teknisk prognos ; Technology forecast