Study of Doppler velocities and their relationship with Magnetic field oscillations in the penumbra of Sunspots
Abstract
Local oscillations of the Doppler Velocities in the penumbra of the sunspot AR12186 were studied. For this
purpose, the images were aligned using the Enhanced Correlation Coefficient (ECC), ECC+Rotation and
the method proposed by Griñón-Marín et al. (2020). The wavelet transform was used to extract the wavelet
power. Analyzing the distribution of the oscillation periods of the wavelet powers locally and globally, no
dominant period was identified in these powers. Also, an attenuation in the Doppler powers of 22,1% and
41,6% was obtained with respect to the powers obtained through the ECC method obtained through the
ECC+Rotation method for the powers found using the the Griñón-Marín et al. (2020) method and ECC
method. In addition, no clear correlation was found between the powers Doppler Velocities, and magnetic
field strength at the line of sight for the three alignment methods.
Keywords
Sun: Doppler velocities -Sun: magnetic fields – Sun: oscillations – Sun: photosphere – sunspotso.
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