Mapping Solar Magnetic Fields from the Photosphere to the Base of the Corona

Abstract

Routine ultraviolet imaging of the Sun's upper atmosphere shows the spectacular manifestation of solar activity; yet we remain blind to its main driver, the magnetic field. Here we report unprecedented spectropolarimetric observations of an active region plage and its surrounding enhanced network, showing circular polarization in ultraviolet (Mg II $h$ & $k$ and Mn I) and visible (Fe I) lines. We infer the longitudinal magnetic field from the photosphere to the very upper chromosphere. At the top of the plage chromosphere the field strengths reach more than 300 gauss, strongly correlated with the Mg II $k$ line core intensity and the electron pressure. This unique mapping shows how the magnetic field couples the different atmospheric layers and reveals the magnetic origin of the heating in the plage chromosphere.

50 pages, 11 figures, 1 table, published in Science Advances

References in corpus (7)

• The Solar Optical Telescope for the Hinode Mission: An Overview
• On the generation of solar spicules and Alfvénic waves
• Magnetic Diagnostics of the Solar Chromosphere with the Mg II h-k Lines
• Recovering Thermodynamics from Spectral Profiles observed by IRIS: A Machine and Deep Learning Approach
• The magnetic sensitivity of the Mg ii k line to the joint action of Hanle, Zeeman and magneto-optical effects
• The magnetic sensitivity of the resonance and subordinate lines of Mg II in the solar chromosphere
• Spectropolarimetry of the Solar Mg II h and k Lines

Cited by in corpus (27)

• Observing the evolution of the Sun's global coronal magnetic field over eight months
• TIC: A Stokes inversion code for scattering polarization with partial frequency redistribution and arbitrary magnetic fields
• Mapping the Sun's coronal magnetic field using the Zeeman effect
• Corona and XUV emission modelling of the Sun and Sun-like stars
• Spatio-temporal analysis of chromospheric heating in a plage region
• Measuring the magnetic origins of solar flares, CMEs and Space Weather
• Modeling the scattering polarization of the solar Ca i 4227 Å line with angle-dependent partial frequency redistribution
• Tomography of a solar plage with the Tenerife Inversion Code
• The transfer of polarized radiation in resonance lines with partial frequency redistribution, J-state interference, and arbitrary magnetic fields. A radiative transfer code and useful approximations
• Magnetic connections across the chromosphere-corona transition region
• Coronal energy release by MHD avalanches. Effects on a structured, active region, multi-threaded coronal loop
• The circular polarization of the Mn I resonance lines around 280 nm for exploring chromospheric magnetism
• Optimal spectral lines for measuring chromospheric magnetic fields
• Effects of spectral resolution on simple magnetic field diagnostics of the Mg II h & k lines
• Spectral lines in FUV and EUV for diagnosing coronal magnetic field
• Formation of the Mg II h and k polarization profiles in a solar plage model and their suitability to infer magnetic fields
• The Effect of the Chromospheric Temperature on Coronal Heating
• Evidence for the Operation of the Hanle and Magneto-Optical Effects in the Scattering Polarization Signals Observed by CLASP2 Across the Mg II h and k Lines
• Multi-fluid Simulation of Solar Chromospheric Turbulence and Heating Due to the Thermal Farley-Buneman Instability
• The magnetic sensitivity of the (250-278nm) Fe II polarization spectrum
• Determining the Magnetic Field in the Atmosphere of a Solar Active Region Observed by the CLASP2.1 Sounding Rocket Experiment
• Recovering thermodynamics from spectral profiles observed by IRIS (II): improved calculation of the uncertainties based on Monte Carlo experiments
• Derivation of Instrument Requirements for Polarimetry using Mg, Fe, and Mn lines between 250 and 290 nm
• Magnetic Imaging of the Outer Solar Atmosphere (MImOSA): Unlocking the driver of the dynamics in the upper solar atmosphere
• The magnetic sensitivity of the Ca II H and K lines
• Proposal of a Novel Physical Parameter Characterizing Solar Wind Speed in a Wave-Driven Model
• Testing the Alfvén-wave model of the solar wind with interplanetary scintillation