Spectropolarimetric inversions of the Ca II 8498 A and 8542 A lines in the quiet Sun

Abstract

We study non-LTE inversions of the Ca II infrared triplet lines as a tool for inferring physical properties of the quiet Sun. The inversion code is successful in recovering the temperature, velocity and longitudinal magnetic flux density in the photosphere and chromosphere, but the height range where the inversions are sensitive is limited, especially in the chromosphere. We present results of inverting spectropolarimetric observations of the lines in a quiet Sun region. We find three distinct ranges in chromospheric temperature: low temperatures in the internetwork, high temperatures in the enhanced magnetic network and intermediate temperatures associated with low magnetic flux regions in the network. The differences between these regions become more pronounced with height as the plasma-$\beta$ decreases. These inversions support the picture of the chromosphere, especially close to the magnetic network, being highly inhomogeneous both in the vertical and horizontal directions.

31 pages, 13 figures, accepted to ApJ

References in corpus (8)

• Solar Atmospheric Oscillations and the Chromospheric Magnetic Topology
• SPINOR: Visible and Infrared Spectro-Polarimetry at the National Solar Observatory
• The Three-Dimensional Structure of a Sunspot Magnetic Field
• Quiet Sun magnetic fields from simultaneous inversions of visible and infrared spectropolarimetric observations
• Zero-Field Dichroism in the Solar Chromosphere
• Signatures of Incomplete Paschen-Back Splitting in the Polarization Profiles of the He I 10830 multiplet
• Milne-Eddington inversions of the He I 10830 Å Stokes profiles: Influence of the Paschen-Back effect
• Simulation of quiet Sun waves in the Ca II infrared triplet

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