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S. Jafarzadeh et. al. ; ©2017 The American Astronomical Society. All rights reserved.A dense forest of slender bright fibrils near a small solar active region is seen in high-quality narrowband Ca ii H images from the SuFI instrument onboard the Sunrise balloon-borne solar observatory. The orientation of these slender Ca ii H fibrils (SCF) overlaps with the magnetic field configuration in the low solar chromosphere derived by magnetostatic extrapolation of the photospheric field observed with Sunrise/IMaX and SDO/HMI. In addition, many observed SCFs are qualitatively aligned with small-scale loops computed from a novel inversion approach based on best-fit numerical MHD simulation. Such loops are organized in canopy-like arches over quiet areas that differ in height depending on the field strength near their roots. ; The German contribution to Sunrise and its reflight was funded by the Max Planck Foundation, the Strategic Innovations Fund of the President of the Max Planck Society (MPG), DLR, and private donations by supporting members of the Max Planck Society, which is gratefully acknowledged. The Spanish contribution was funded by the Ministerio de Economía y Competitividad under Projects ESP2013-47349-C6 and ESP2014-56169-C6, partially using European FEDER funds. The HAO contribution was partly funded through NASA grant number NNX13AE95G. This work was partly supported by the BK21 plus program through the National Research Foundation (NRF) funded by the Ministry of Education of Korea. S.J. receives support from the Research Council of Norway. T.W. acknowledges support by DFG-grant WI 3211/4-1. M.S. acknowledges support from the European Research Council under the European Union's Seventh Framework Programme / ERC Grant agreement nr. 291058. ; Peer reviewed

L. P. Chitta et. al. ; ©2017 The American Astronomical Society. All rights reserved. How and where are coronal loops rooted in the solar lower atmosphere? The details of the magnetic environment and its evolution at the footpoints of coronal loops are crucial to understanding the processes of mass and energy supply to the solar corona. To address the above question, we use high-resolution line-of-sight magnetic field data from the Imaging Magnetograph eXperiment instrument on the Sunrise balloon-borne observatory and coronal observations from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory of an emerging active region. We find that the coronal loops are often rooted at the locations with minor small-scale but persistent opposite-polarity magnetic elements very close to the larger dominant polarity. These opposite-polarity small-scale elements continually interact with the dominant polarity underlying the coronal loop through flux cancellation. At these locations we detect small inverse Y-shaped jets in chromospheric Ca ii H images obtained from the Sunrise Filter Imager during the flux cancellation. Our results indicate that magnetic flux cancellation and reconnection at the base of coronal loops due to mixed polarity fields might be a crucial feature for the supply of mass and energy into the corona. ; L.P.C. acknowledges funding by the Max-Planck-Princeton Center for Plasma Physics and funding from the European Union's Horizon 2020 research and innovation program under Marie Skłodowska-Curie grant agreement No. 707837. The German contribution to Sunrise and its reflight was funded by the Max Planck Foundation, the Strategic Innovations Fund of the President of the Max Planck Society (MPG), DLR, and private donations by supporting members of the Max Planck Society, which is gratefully acknowledged. The Spanish contribution was funded by the Ministerio de Economía y Competitividad under Projects ESP2013-47349-C6 and ESP2014-56169-C6, partially using European FEDER funds. The HAO contribution was partly funded through NASA grant number NNX13AE95G. SDO data are the courtesy of NASA/SDO and the AIA, and HMI science teams. This work was partly supported by the BK21 plus program through the National Research Foundation (NRF) funded by the Ministry of Education of Korea ; Peer reviewed

All authors: Rouillard, A. P.; Pinto, R. F.; Vourlidas, A.; De Groof, A.; Thompson, W. T.; Bemporad, A.; Dolei, S.; Indurain, M.; Buchlin, E.; Sasso, C.; Spadaro, D.; Dalmasse, K.; Hirzberger, J.; Zouganelis, I.; Strugarek, A.; Brun, A. S.; Alexandre, M.; Berghmans, D.; Raouafi, N. E.; Wiegelmann, T.; Pagano, P.; Arge, C. N.; Nieves-Chinchilla, T.; Lavarra, M.; Poirier, N.; Amari, T.; Aran, A.; Andretta, V.; Antonucci, E.; Anastasiadis, A.; Auchère, F.; Bellot Rubio, L.; Nicula, B.; Bonnin, X.; Bouchemit, M.; Budnik, E.; Caminade, S.; Cecconi, B.; Carlyle, J.; Cernuda, I.; Davila, J. M.; Etesi, L.; Espinosa Lara, F.; Fedorov, A.; Fineschi, S.; Fludra, A.; Génot, V.; Georgoulis, M. K.; Gilbert, H. R.; Giunta, A.; Gomez-Herrero, R.; Guest, S.; Haberreiter, M.; Hassler, D.; Henney, C. J.; Howard, R. A.; Horbury, T. S.; Janvier, M.; Jones, S. I.; Kozarev, K.; Kraaikamp, E.; Kouloumvakos, A.; Krucker, S.; Lagg, A.; Linker, J.; Lavraud, B.; Louarn, P.; Maksimovic, M.; Maloney, S.; Mann, G.; Masson, A.; Müller, D.; Önel, H.; Osuna, P.; Orozco Suarez, D.; Owen, C. J.; Papaioannou, A.; Pérez-Suárez, D.; Rodriguez-Pacheco, J.; Parenti, S.; Pariat, E.; Peter, H.; Plunkett, S.; Pomoell, J.; Raines, J. M.; Riethmüller, T. L.; Rich, N.; Rodriguez, L.; Romoli, M.; Sanchez, L.; Solanki, S. K.; St Cyr, O. C.; Straus, T.; Susino, R.; Teriaca, L.; del Toro Iniesta, J. C.; Ventura, R.; Verbeeck, C.; Vilmer, N.; Warmuth, A.; Walsh, A. P.; Watson, C.; Williams, D.; Wu, Y.; Zhukov, A. N.-- Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ; Context. The Solar Orbiter spacecraft will be equipped with a wide range of remote-sensing (RS) and in situ (IS) instruments to record novel and unprecedented measurements of the solar atmosphere and the inner heliosphere. To take full advantage of these new datasets, tools and techniques must be developed to ease multi-instrument and multi-spacecraft studies. In particular the currently inaccessible low solar corona below two solar radii can only be observed remotely. Furthermore techniques must be used to retrieve coronal plasma properties in time and in three dimensional (3D) space. Solar Orbiter will run complex observation campaigns that provide interesting opportunities to maximise the likelihood of linking IS data to their source region near the Sun. Several RS instruments can be directed to specific targets situated on the solar disk just days before data acquisition. To compare IS and RS, data we must improve our understanding of how heliospheric probes magnetically connect to the solar disk. Aims. The aim of the present paper is to briefly review how the current modelling of the Sun and its atmosphere can support Solar Orbiter science. We describe the results of a community-led effort by European Space Agency's Modelling and Data Analysis Working Group (MADAWG) to develop different models, tools, and techniques deemed necessary to test different theories for the physical processes that may occur in the solar plasma. The focus here is on the large scales and little is described with regards to kinetic processes. To exploit future IS and RS data fully, many techniques have been adapted to model the evolving 3D solar magneto-plasma from the solar interior to the solar wind. A particular focus in the paper is placed on techniques that can estimate how Solar Orbiter will connect magnetically through the complex coronal magnetic fields to various photospheric and coronal features in support of spacecraft operations and future scientific studies. Methods. Recent missions such as STEREO, provided great opportunities for RS, IS, and multi-spacecraft studies. We summarise the achievements and highlight the challenges faced during these investigations, many of which motivated the Solar Orbiter mission. We present the new tools and techniques developed by the MADAWG to support the science operations and the analysis of the data from the many instruments on Solar Orbiter. Results. This article reviews current modelling and tool developments that ease the comparison of model results with RS and IS data made available by current and upcoming missions. It also describes the modelling strategy to support the science operations and subsequent exploitation of Solar Orbiter data in order to maximise the scientific output of the mission. Conclusions. The on-going community effort presented in this paper has provided new models and tools necessary to support mission operations as well as the science exploitation of the Solar Orbiter data. The tools and techniques will no doubt evolve significantly as we refine our procedure and methodology during the first year of operations of this highly promising mission. © 2020 A. P. Rouillard et al. ; Solar Orbiter is a joint ESA and NASA mission. A. Vourlidas' Solar Orbiter effort is supported by NRL grant N00173-16-1-G029. P. Pagano would like to thank D. H. Mackay and S. L. Yardley for their valuable contributions, the European Research Council (ERC) under the European Union Horizon 2020 research and innovation program (grant agreement No. 647214), and the DiRAC Data Centric system at Durham University, operated by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (http://www.dirac.ac.uk).This equipment was funded by a BIS National E-infrastructure capital grant ST/K00042X/1, STFC capital grant ST/K00087X/1, DiRAC Operations grant ST/K003267/1 and Durham University. DiRAC is part of the National E-Infrastructure. A. Rouillard, V. Genot, M. Janvier, Elie Soubrier, F. Auchere, E. Buchlin and E. Pariat acknowledge support from the French space agency (Centre National d'Etudes Spatiales; CNES; https://cnes.fr/fr) that funds activity in plasma physics data center (Centre de Donnees de la Physique des Plasmas; CDPP; http://cdpp.eu/) and the Multi Experiment Data and Operation Center (MEDOC; https://idoc.ias.u-psud.fr/MEDOC), and the space weather team in Toulouse (Solar-Terrestrial Observations and Modelling Service; STORMS; http://storms-service.irap.omp.eu/).This includes funding for Gaia-DEM, the data mining tools AMDA (http://amda.cdpp.eu/), CLWEB (clweb.cesr. fr/) and the propagation tool (http://propagationtool.cdpp.eu).R.Pinto, M. Lavarra, Y. Wu and A. Kouloumvakos acknowledge financial support from the ANR project SLOW_ SOURCE No. ANR-17-CE31-0006-01, ANR project COROSHOCK No. ANR-18-ERC1-0006-01 and FP7 HELCATS project https://www.helcats-fp7.eu/under the FP7 EU contract number 606692. A. Warmuth acknowledges the support by DLR under grant No. 50 QL 0001. The STEREO SECCHI data are produced by a consortium of RAL (UK), NRL (USA), LMSAL (USA), GSFC (USA), MPS (Germany), CSL (Belgium), IOTA (France) and IAS (France). The ACE data were obtained from the ACE science center. The WIND data were obtained from the Space Physics Data Facility. Javier Rodriguez-Pacheco acknowledges Spanish Project: FEDER/MCIU-AEI/Project ESP2017-88436-R.

©2017 The American Astronomical Society. All rights reserved. We study the relation between mesogranular flows, convectively driven sinks and magnetic fields using high spatial resolution spectropolarimetric data acquired with the Imaging Magnetograph eXperiment on board Sunrise. We obtain the horizontal velocity flow fields of two quiet-Sun regions (31.2 × 31.2 Mm2) via local correlation tracking. Mesogranular lanes and the central position of sinks are identified using Lagrange tracers. We find $6.7\times {10}^{-2}$ sinks per Mm2 in the two observed regions. The sinks are located at the mesogranular vertices and turn out to be associated with (1) horizontal velocity flows converging to a central point and (2) long-lived downdrafts. The spatial distribution of magnetic fields in the quiet-Sun is also examined. The strongest magnetic fields are preferentially located at sinks. We find that 40% of the pixels with longitudinal components of the magnetic field stronger than 500 G are located in the close neighborhood of sinks. In contrast, the small-scale magnetic loops detected by Martínez González et al. in the same two observed areas do not show any preferential distribution at mesogranular scales. The study of individual examples reveals that sinks can play an important role in the evolution of quiet-Sun magnetic features. ; The work by I.S.R. has been funded by the Basque Government under a grant from Programa Predoctoral de Formación de Personal Investigador del Departamento de Educación, Universidades e Investigación. This work has been partially funded by the Spanish Ministerio de Economía y Competitividad, through Projects No. ESP2013-47349-C6-1-R and ESP2014-56169-C6-1-R, including a percentage from European FEDER funds. The German contribution has been funded by the Bundesministerium für Wirtschaft und Technologie through Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), grant number 50 OU 0401, and by the Innovationsfond of the President of the Max Planck Society (MPG). This work was partly supported by the BK21 plus program through the National Research Foundation (NRF) funded by the Ministry of Education of Korea. ; Peer reviewed

Open Access. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. ; We study the photospheric evolution of an exploding granule observed in the quiet Sun at high spatial (similar to 03) and temporal (31.5 s) resolution by the imaging magnetographSunrise/IMaX in 2009 June. These observations show that the exploding granule is cospatial to a magnetic flux emergence event occurring at mesogranular scale (up to similar to 12 Mm(2)area). Using a modified version of the SIR code for inverting the IMaX spectropolarimetric measurements, we obtain information about the magnetic configuration of this photospheric feature. In particular, we find evidence of highly inclined emerging fields in the structure, carrying a magnetic flux content up to similar to 4 x 10(18)Mx. The balance between gas and magnetic pressure in the region of flux emergence, compared with a very quiet region of the Sun, indicates that the additional pressure carried by the emerging flux increases the total pressure by about 5% and appears to allow the granulation to be modified, as predicted by numerical simulations. The overall characteristics suggest that a multipolar structure emerges into the photosphere, resembling an almost horizontal flux sheet. This seems to be associated with exploding granules. Finally, we discuss the origin of such flux emergence events. © 2020. The Author(s). Published by the American Astronomical Society. ; This research has received funding from the European Commission's Seventh Framework Programme under the grant agreement No. 312495 (SOLARNET project) and from the European Union's Horizon 2020 research and innovation program under the grant agreements No. 739500 (PRE-EST project) and no. 824135 (SOLARNET project). S.L.G. and F.Z. acknowledge support by the Italian MIUR-PRIN grant 2017APKP7T on Circumterrestrial Environment: Impact of Sun-Earth Interaction, by the Universita degli Studi di Catania (Piano per la Ricerca Universita di Catania 2016-2018 -Linea di intervento 1 "Chance"'; Linea di intervento 2 "Dotazione ordinaria"; Fondi di Ateneo 2020-2022, Universita di Catania, Linea Open Access), by the Istituto Nazionale di Astrofisica (PRIN INAF 2010/2014), and by the Space Weather Italian COmmunity (SWICO) Research Program. This project has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program (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. The National Solar Observatory (NSO) is operated by the Association of Universities for Research in Astronomy, Inc. (AURA), under cooperative agreement with the National Science Foundation. This work has been partially funded by the Spanish Ministerio de Educacion y Ciencia, through Projects ESP2006-13030-C06-01/02/03/04 and AYA2009-14105-C06, by the Spanish Ministry of Economy and Competitiveness through Project ESP-2016-77548-C5, and by Junta de Andalucia, through Project P07-TEP-2687, including a percentage from European FEDER funds. L.R.B.R. and J.C.T.I. acknowledge financial support from the State Agency for Research of the Spanish Ministerio de Ciencia, Innovacion y Universidades through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709). The German contribution to SUNRISE is funded by the Bundesministerium fur Wirtschaft und Technologie through Deutsches Zentrum fur Luft-und Raumfahrt e.V. (DLR), grant No. 50 OU 0401, and by the Innovationsfond of the President of the Max Planck Society (MPG). Use of NASA's Astrophysical Data System is gratefully acknowledged. This article honors the memory of Prof. Egidio Landi degl'Innocenti, who passed away while this paper was being written. The most important results were discussed during the Solar Polarization Workshop 8, which was held in his honor. ; Peer reviewed