@article{3dee16bf93704fa59f4f2ba8e85db9d1,
title = "First perihelion of EUI on the Solar Orbiter mission",
abstract = "Context. The Extreme Ultraviolet Imager (EUI) on board Solar Orbiter consists of three telescopes: the two High Resolution Imagers, in EUV (HRIEUV) and in Lyman-α (HRILya), and the Full Sun Imager (FSI). Solar Orbiter/EUI started its Nominal Mission Phase on 2021 November 27. Aims. Our aim is to present the EUI images from the largest scales in the extended corona off-limb down to the smallest features at the base of the corona and chromosphere. EUI is therefore a key instrument for the connection science that is at the heart of the Solar Orbiter mission science goals. Methods. The highest resolution on the Sun is achieved when Solar Orbiter passes through the perihelion part of its orbit. On 2022 March 26, Solar Orbiter reached, for the first time, a distance to the Sun close to 0.3 au. No other coronal EUV imager has been this close to the Sun. Results. We review the EUI data sets obtained during the period 2022 March- April, when Solar Orbiter quickly moved from alignment with the Earth (2022 March 6), to perihelion (2022 March 26), to quadrature with the Earth (2022 March 29). We highlight the first observational results in these unique data sets and we report on the in-flight instrument performance. Conclusions. EUI has obtained the highest resolution images ever of the solar corona in the quiet Sun and polar coronal holes. Several active regions were imaged at unprecedented cadences and sequence durations. We identify in this paper a broad range of features that require deeper studies. Both FSI and HRIEUV operated at design specifications, but HRILya suffered from performance issues near perihelion. We conclude by emphasizing the EUI open data policy and encouraging further detailed analysis of the events highlighted in this paper.",
keywords = "Instrumentation: high angular resolution, Prominences, Sun: chromosphere, Sun: corona, Sun: coronal mass ejections (CMEs), Sun: filaments, Sun: flares",
author = "D. Berghmans and P. Antolin and F. Auch{\`e}re and {Aznar Cuadrado}, R. and K. Barczynski and Chitta, {L. P.} and S. Gissot and L. Harra and Z. Huang and M. Janvier and E. Kraaikamp and Long, {David M.} and S. Mandal and M. Mierla and S. Parenti and H. Peter and L. Rodriguez and U. Sch{\"u}hle and Smith, {P. J.} and Solanki, {S. K.} and K. Stegen and L. Teriaca and C. Verbeeck and West, {M. J.} and Zhukov, {A. N.} and T. Appourchaux and G. Aulanier and E. Buchlin and F. Delmotte and Gilles, {J. M.} and M. Haberreiter and Halain, {J. P.} and K. Heerlein and Hochedez, {J. F.} and M. Gyo and S. Poedts and E. Renotte and P. Rochus",
note = "Funding information: The building of EUI was the work of more than 150 individuals during more than 10 years. We gratefully acknowledge all the efforts that have led to a successfully operating instrument. The authors thank the Belgian Federal Science Policy Office (BELSPO) for the provision of financial support in the framework of the PRODEX Programme of the European Space Agency (ESA) under contract numbers 4000112292, 4000134088, 4000134474, and 4000136424. The French contribution to the EUI instrument was funded by the French Centre National d{\textquoteright}{\'E}tudes Spatiales (CNES); the UK Space Agency (UKSA); the Deutsche Zentrum f{\"u}r Luft- und Raumfahrt e.V. (DLR); and the Swiss Space Office (SSO). PA and DML acknowledge funding from STFC Ernest Rutherford Fellowships No. ST/R004285/2 and ST/R003246/1, respectively. SP acknowledges the funding by CNES through the MEDOC data and operations center. L.P.C. gratefully acknowledges funding by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council (grant agreement No 101039844). Neither the European Union nor the granting authority can be held responsible for them.",
year = "2023",
month = jul,
doi = "10.1051/0004-6361/202245586",
language = "English",
volume = "675",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",
}