2017/05/29 by C. Quintero Noda, H. Uitenbroek, Y. Katsukawa +15 · 24 citations
Computer Science · Physics and Astronomy · #Astronomy #Astrophysics #Field line #Infrared #Line (geometry) #Magnetic field #Photosphere #Physics #Solar Radiation and Photovoltaics #Solar and Space Plasma Dynamics #Spectral line #Stellar, planetary, and galactic studies #Sunspot #Zeeman effect #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stx1344
published in Monthly Notices of the Royal Astronomical Society 470(2), 1453-1461 (Oxford University Press) · 10 pages, 9 figures, main journal publication
arxiv created 2017/05/29 · openalex publication_date 2017/05/31 · arxiv updated 2017/07/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We characterize the K i D1 & D2 lines in order to determine whether they could complement the 850 nm window, containing the Ca ii infrared triplet lines and several Zeeman sensitive photospheric lines, that was studied previously. We investigate the effect of partial redistribution on the intensity profiles, their sensitivity to changes in different atmospheric parameters, and the spatial distribution of Zeeman polarization signals employing a realistic magnetohydrodynamic simulation. The results show that these lines form in the upper photosphere at around 500 km, and that they are sensitive to the line-of-sight velocity and magnetic field strength at heights where neither the photospheric lines nor the Ca ii infrared lines are. However, at the same time, we found that their sensitivity to the temperature essentially comes from the photosphere. Then, we conclude that the K i lines provide a complement to the lines in the 850 nm window for the determination of atmospheric parameters in the upper photosphere, especially for the line-of-sight velocity and the magnetic field.