Measurement of the Height of the Chromospheric Network Emission from Solar Dynamics Observatory Images

Abstract

We measured the height of the chromospheric network in the 1700, 1600, and 304 Å wavelength bands of the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) from the shift of features on the disk with respect to corresponding features in SDO/Helioseismic and Magnetic Imager (HMI) images of the absolute value of the longitudinal magnetic field. We found that near the limb the 304 Å network emission forms $3.60\pm 0.24$ Mm above the 1600 Å emission, which, in turn, forms $0.48\pm 0.10$ Mm above the HMI (6173 Å) level. At the center of the disk the corresponding height differences are $2.90\pm 0.02$ Mm and $0.39\pm 0.06$ Mm respectively. We also found that the 1600 Å network emission forms $0.25\pm 0.02$ Mm above the 1700 Å emission near the limb and $0.20\pm 0.02$ Mm at the disk center. Finally, we examined possible variations with the solar cycle. Our results can help to check and refine atmospheric models.