Letter to the Editor

Solar oxygen abundance using SST/CRISP center-to-limb observations of the O I 7772 Å line

¹ Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany
e-mail: apietrow@aip.de
² Institute for Solar Physics, Department of Astronomy, Stockholm University, Albanova University Centre, 106 91 Stockholm, Sweden
³ Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
⁴ Scientific Computing and Research Support Unit, University of Lausanne, 1015 Lausanne, Switzerland

Received: 12 March 2023
Accepted: 3 April 2023

Abstract

Solar oxygen abundance measurements based on the O I near-infrared triplet have been a much debated subject for several decades, since non-local thermodynamic equilibrium (NLTE) calculations with 3D radiation-hydrodynamics model atmospheres introduced a large change to the 1D LTE modeling. In this work, we aim to test solar line formation across the solar disk using new observations obtained with the SST/CRISP instrument. The observed data set is based on a spectroscopic mosaic that stretches from disk center to the solar limb. By comparing the state-of-the-art 3D NLTE models with the data, we find that the 3D NLTE models provide an excellent description of the line formation across the disk. We obtain an abundance value of A(O)=(8.73 ± 0.03) dex, with a very small angular dispersion across the disk. We conclude that spectroscopic mosaics are excellent probes for geometric and physical properties of hydrodynamics models and NLTE line formation.