Science Requirement Document (SRD) for the European Solar Telescope (EST) (3rd Edition, December 2025)

Rolf Schlichenmaier; Luis R. Bellot Rubio; Manuel Collados Vera; Robertus Erdelyi; Alex Feller; Lyndsay Fletcher; Jan Jurčák; Elena Khomenko; Jorrit Leenaarts; Sara Matthews; Luca Belluzzi; Mats Carlsson; Sanja Danilovic; Peter Gömöry; Christoph Kuckein; Rafail Manso Sainz; Marián Martínez González; Mihalis Mathioudakis; Ada Ortiz; Tino L. Riethmüller; Luc Rouppe van der Voort; Paolo J. A. Simoes; Javier Trujillo Bueno; Dominik Utz; Francesca Zuccarello; Jaime de la Cruz Rodriguez; Luca Giovanelli; Shahin Jafarzadeh; David B. Jess; Ivan Milic; Chris Nelson; Michiel van Noort; Claudia Ruiz de Galarreta; Franziska Zeuner

arXiv · 1912.08650

Science Requirement Document (SRD) for the European Solar Telescope (EST) (3rd Edition, December 2025)

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Abstract

The European Strategy Forum on Research Infrastructures (ESFRI) included the European Solar Telescope (EST) as an ESFRI Project in its 2016 Roadmap and confirmed this status in 2021. During the Preparatory Phase (2017 to 2022), the EST Science Advisory Group (SAG) was established in 2017. Its first task was to revise the Science Requirements Document (SRD), originally formulated in 2011. This second edition of the SRD was published in December 2019 (Schlichenmaier et al. 2019, 2019arXiv191208650S). Since 2019, the EST Project Office has advanced the telescope design and developed the Science Instrumentation Suite (SIS). All telescope subsystems and the SIS have now passed their Design Reviews. Aligned with the discussions and resolutions of the SAG, the SIS comprises three categories of first-generation instruments: (1) Tunable Imaging Spectropolarimeters coupled with Fixed Band Imagers (TIS/FBIs), employing large-aperture Fabry-Pérot etalons; (2) Integral Field Spectropolarimeters based on microlens arrays (IFS-M); (3) The near-infrared spectropolarimeter EMBER (spectropolariMeter Based on slicEr-mirrors for the near-infraRed), using image-slicing technology. This configuration enables simultaneous observations of the same two-dimensional solar region across a broad wavelength range (380-2200 nm), giving EST a uniquely powerful multi-wavelength observing capability. This has made it necessary to revise the Observing Programmes so that they accurately reflect the capabilities of the SIS and ensure that all science objectives can be met. This third edition of the EST SRD integrates the outcomes of numerous SAG meetings held between 2020 and 2025 and incorporates all design developments up to 2025. It updates the Observing Programmes accordingly and assesses their alignment with the scientific objectives defined by the SAG.

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Rolf Schlichenmaier, Luis R. Bellot Rubio, Manuel Collados Vera, Robertus Erdelyi, Alex Feller, Lyndsay Fletcher, Jan Jurčák, Elena Khomenko, Jorrit Leenaarts, Sara Matthews, Luca Belluzzi, Mats Carlsson, Sanja Danilovic, Peter Gömöry, Christoph Kuckein, Rafail Manso Sainz, Marián Martínez González, Mihalis Mathioudakis, Ada Ortiz, Tino L. Riethmüller, Luc Rouppe van der Voort, Paolo J. A. Simoes, Javier Trujillo Bueno, Dominik Utz, Francesca Zuccarello, Jaime de la Cruz Rodriguez, Luca Giovanelli, Shahin Jafarzadeh, David B. Jess, Ivan Milic, Chris Nelson, Michiel van Noort, Claudia Ruiz de Galarreta, Franziska Zeuner. 2025-12-18. Science Requirement Document (SRD) for the European Solar Telescope (EST) (3rd Edition, December 2025). https://arxiv.org/abs/1912.08650

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