edu.ucar.opensky::articles:25958 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T19:56:48.529731 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7m04990 Optimal spectral lines for measuring chromospheric magnetic fields 2022-12-01T00:00:00Z publication https://n2t.org/ark:/85065/d7m04990 https://doi.org/10.3847/1538-4357/aca2a5 Judge, Philip G. author Bryans, Paul author Casini, Roberto author Kleint, L. author Lacatus, Daniela A. author Paraschiv, Alin Razvan author Schmit, D. author UCAR/NCAR - Library publisher This paper identifies spectral lines from X-ray to IR wavelengths which are optimally suited to measuring vector magnetic fields as high as possible in the solar atmosphere. Instrumental and Earth's atmospheric properties, as well as solar abundances, atmospheric properties, and elementary atomic physics are considered without bias toward particular wavelengths or diagnostic techniques. While narrowly focused investigations of individual lines have been reported in detail, no assessment of the comparative merits of all lines has ever been published. Although in the UV, on balance the Mg+ h and k lines near 2800 angstrom are optimally suited to polarimetry of plasma near the base of the solar corona. This result was unanticipated, given that longer-wavelength lines offer greater sensitivity to the Zeeman effect. While these lines sample optical depths photosphere to the coronal base, we argue that cores of multiple spectral lines provide a far more discriminating probe of magnetic structure as a function of optical depth than the core and inner wings of a strong line. Thus, together with many chromospheric lines of Fe+ between 2585 angstrom and the h line at 2803 angstrom, this UV region promises new discoveries concerning how the magnetic fields emerge, heat, and accelerate plasma as they battle to dominate the force and energy balance within the poorly understood chromosphere. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation