2022, Quintero Noda, C., Schlichenmaier, R., Bellot Rubio, L.R., Löfdahl, M.G., Khomenko, E., Jurčák, J., Leenaarts, J., Kuckein, C., González Manrique, S.J., Gunár, S., Nelson, C.J., Giovannelli, L., González, F., González, J.B., González-Cava, J.M., González García, M., Gömöry, P., Gracia, F., Grauf, B., Greco, V., Grivel, C., de la Cruz Rodríguez, J., Guerreiro, N., Guglielmino, S.L., Hammerschlag, R., Hanslmeier, A., Hansteen, V., Heinzel, P., Hernández-Delgado, A., Hernández Suárez, E., Hidalgo, S.L., Hill, F., Tziotziou, K., Hizberger, J., Hofmeister, S., Jägers, A., Janett, G., Jarolim, R., Jess, D., Jiménez Mejías, D., Jolissaint, L., Kamlah, R., Kapitán, J., Tsiropoula, G., Kašparová, J., Keller, C.U., Kentischer, T., Kiselman, D., Kleint, L., Klvana, M., Kontogiannis, I., Krishnappa, N., Kučera, A., Labrosse, N., Aulanier, G., Lagg, A., Landi Degl’Innocenti, E., Langlois, M., Lafon, M., Laforgue, D., Le Men, C., Lepori, B., Lepreti, F., Lindberg, B., Lilje, P.B., Aboudarham, J., López Ariste, A., López Fernández, V.A., López Jiménez, A.C., López López, R., Manso Sainz, R., Marassi, A., Marco de la Rosa, J., Marino, J., Marrero, J., Martín, A., Allegri, D., Martín Gálvez, A., Martín Hernando, Y., Masciadri, E., Martínez González, M., Matta-Gómez, A., Mato, A., Mathioudakis, M., Matthews, S., Mein, P., Merlos García, F., Alsina Ballester, E., Moity, J., Montilla, I., Molinaro, M., Molodij, G., Montoya, L.M., Munari, M., Murabito, M., Núñez Cagigal, M., Oliviero, M., Orozco Suárez, D., Amans, J.P., Ortiz, A., Padilla-Hernández, C., Paéz Mañá, E., Paletou, F., Pancorbo, J., Pastor Cañedo, A., Pastor Yabar, A., Peat, A.W., Pedichini, F., Peixinho, N., Asensio Ramos, A., Peñate, J., Pérez de Taoro, A., Peter, H., Petrovay, K., Piazzesi, R., Pietropaolo, E., Pleier, O., Poedts, S., Pötzi, W., Podladchikova, T., Bailén, F.J., Prieto, G., Quintero Nehrkorn, J., Ramelli, R., Ramos Sapena, Y., Rasilla, J.L., Reardon, K., Rebolo, R., Regalado Olivares, S., Reyes García-Talavera, M., Riethmüller, T.L., Balaguer, M., Rimmele, T., Rodríguez Delgado, H., Rodríguez González, N., Rodríguez-Losada, J.A., Rodríguez Ramos, L.F., Romano, P., Roth, M., Rouppe van der Voort, L., Rudawy, P., Ruiz de Galarreta, C., Baldini, V., Rybák, J., Salvade, A., Sánchez-Capuchino, J., Sánchez Rodríguez, M.L., Sangiorgi, M., Sayède, F., Scharmer, G., Scheiffelen, T., Schmidt, W., Schmieder, B., Balthasar, H., Scirè, C., Scuderi, S., Siegel, B., Sigwarth, M., Simões, P.J.A., Snik, F., Sliepen, G., Sobotka, M., Socas-Navarro, H., Sola La Serna, P., Barata, T., Solanki, S. K., Soler Trujillo, M., Soltau, D., Sordini, A., Sosa Méndez, A., Stangalini, M., Steiner, O., Stenflo, J.O., Štěpán, J., Strassmeier, K.G., Barczynski, K., Sudar, D., Suematsu, Y., Sütterlin, P., Tallon, M., Temmer, M., Tenegi, F., Tritschler, A., Trujillo Bueno, J., Turchi, A., Utz, D., Barreto Cabrera, M., van Harten, G., van Noort, M., van Werkhoven, T., Vansintjan, R., Vaz Cedillo, J.J., Vega Reyes, N., Verma, M., Veronig, A.M., Viavattene, G., Vitas, N., Baur, A., Vögler, A., von der Lühe, O., Volkmer, R., Waldmann, T.A., Walton, D., Wisniewska, A., Zeman, J., Zeuner, F., Zhang, L.Q., Zuccarello, F., Béchet, C., Collados, M., Beck, C., Belío-Asín, M., Bello-González, N., Belluzzi, L., Bentley, R.D., Berdyugina, S.V., Berghmans, D., Berlicki, A., Berrilli, F., Berkefeld, T., Bettonvil, F., Bianda, M., Bienes Pérez, J., Bonaque-González, S., Brajša, R., Bommier, V., Bourdin, P.-A., Burgos Martín, J., Calchetti, D., Calcines, A., Calvo Tovar, J., Campbell, R.J., Carballo-Martín, Y., Carbone, V., Carlin, E.S., Carlsson, M., Castro López, J., Cavaller, L., Cavallini, F., Cauzzi, G., Cecconi, M., Chulani, H.M., Cirami, R., Consolini, G., Coretti, I., Cosentino, R., Cózar-Castellano, J., Dalmasse, K., Danilovic, S., De Juan Ovelar, M., Del Moro, D., del Pino Alemán, T., del Toro Iniesta, J. C., Denker, C., Dhara, S.K., Di Marcantonio, P., Díaz Baso, C.J., Diercke, A., Dineva, E., Díaz-García, J.J., Doerr, H.-P., Doyle, G., Erdelyi, R., Ermolli, I., Escobar Rodríguez, A., Esteban Pozuelo, S., Faurobert, M., Felipe, T., Feller, A., Feijoo Amoedo, N., Femenía Castellá, B., Fernandes, J., Ferro Rodríguez, I., Figueroa, I., Fletcher, L., Franco Ordovas, A., Gafeira, R., Gardenghi, R., Gelly, B., Giorgi, F., Gisler, D.

The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar physics community during the construction and operation of state-of-the-art solar telescopes operating in visible and near-infrared wavelengths: the Swedish 1m Solar Telescope, the German Vacuum Tower Telescope and GREGOR, the French Télescope Héliographique pour l'Étude du Magnétisme et des Instabilités Solaires, and the Dutch Open Telescope. With its 4.2 m primary mirror and an open configuration, EST will become the most powerful European ground-based facility to study the Sun in the coming decades in the visible and near-infrared bands. EST uses the most innovative technological advances: the first adaptive secondary mirror ever used in a solar telescope, a complex multi-conjugate adaptive optics with deformable mirrors that form part of the optical design in a natural way, a polarimetrically compensated telescope design that eliminates the complex temporal variation and wavelength dependence of the telescope Mueller matrix, and an instrument suite containing several (etalon-based) tunable imaging spectropolarimeters and several integral field unit spectropolarimeters. This publication summarises some fundamental science questions that can be addressed with the telescope, together with a complete description of its major subsystems.

2020, 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., 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., 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.T., 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-Suáre, 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.

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.

2013, Wiegelmann, T., Solanki, S.K., Borrero, J.M., Peter, H., Barthol, P., Gandorfer, A., Martínez Pillet, V., Schmidt, W., Knölker, M.

Observations with the balloon-borne Sunrise/Imaging Magnetograph eXperiment (IMaX) provide high spatial resolution (roughly 100 km at disk center) measurements of the magnetic field in the photosphere of the quiet Sun. To investigate the magnetic structure of the chromosphere and corona, we extrapolate these photospheric measurements into the upper solar atmosphere and analyze a 22-minute long time series with a cadence of 33 seconds. Using the extrapolated magnetic-field lines as tracer, we investigate temporal evolution of the magnetic connectivity in the quiet Sun’s atmosphere. The majority of magnetic loops are asymmetric in the sense that the photospheric field strength at the loop foot points is very different. We find that the magnetic connectivity of the loops changes rapidly with a typical connection recycling time of about 3±1 minutes in the upper solar atmosphere and 12±4 minutes in the photosphere. This is considerably shorter than previously found. Nonetheless, our estimate of the energy released by the associated magnetic-reconnection processes is not likely to be the sole source for heating the chromosphere and corona in the quiet Sun.