Fast prograde coronal flows in solar active regions
نویسندگان
چکیده
ABSTRACT We report the discovery and characterization of high-speed (>100 km s−1) horizontal flows in solar active regions, making use Sun-as-a-star spectroscopy range 5–105 nm provided by EVE (Extreme Ultraviolet Variability Experiment) spectrometers on Solar Dynamics Observatory. These apparent are persistent time-scales days, well observed lines Mg x, Si xii, Fe xvi for example. They prograde, as evidenced directly blueshifts/redshifts peaking at east/west limb passages isolated regions. The flow behaviour does not depend upon active-region latitude or cycle, with similar Cycles 24 25.
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society: Letters
سال: 2022
ISSN: ['1745-3925', '1745-3933']
DOI: https://doi.org/10.1093/mnrasl/slac079