Mehri Heydari - Department of Physics, Payame Noor University (PNU), Tehran, Iran.
Ehsan Tavabi - Department of Physics, Payame Noor University (PNU), Tehran, Iran.

Multi-wavelength observations could help discriminate the fundamental differences for the mechanism of the jet-like structures of the hot and cool material in the inner atmosphere. We use the Atmospheric Imaging Assembly (AIA) on-board the Solar Dynamics Observatory (SDO) for unprecedented temporal and spatial resolving power for a wide range of wavelengths to increase our knowledge about the origin and the evolution of jets. The dynamical behavior of the jets in polar plumes (PP’s) is considered for the first time based on the simultaneously observed in space EUV hot, and cool emission lines also observed in W-L at total eclipses. At the USA ۲۰۱۷ total solar eclipse, we observed white-light polar plumes (W-L PPs) with an excellent resolution from different sites. We tried several combinations of pictures taken (a) from different sites on the ground, using different image processing (techniques), and (b) from space, taken with different coronal filters and time sequences. The resolution of the faint polar regions space images are of low signal/noise (S/N) ratio, and instead of summing pixels of images to reduce the noise of individual images, we found it more efficient to sum a burst of ۵ to ۱۰ min consecutive AIA frames from a sequence taken around the total eclipse time. This should smear out the fast dynamical events showing fast dynamical events, but the jet part is not significantly smeared, as the flow being linear. We also found promising results using the ۱۷۱ Å filter with temperature sensitivity extended from ۰.۶ MK to ۲ MK due to lines of Fe IX, Fe X and Ni XIV but also performed the analysis with the higher temperature sensitivity filters, at ۱۹۳ and ۲۱۱ Å. The relationships of W-L PP’s with inner parts off-limb EUV emission lines jet-like structures demonstrated a highly correlated behavior. In most cases, we found a cross-correlation coefficient in order of ۸۵% in coronal hole regions; however, this correlation is not perfect in some cases. Therefore, in these features, the direct connection was not detectable obviously, the disparity could be related to Doppler dimming effect in high velocity jet like plums. However, most W-L plumes have counterparts with EUV ray.

total eclipse, corona, polar plume, Polar-rays