Coronal Waves Associated with Solar Flares

Noriyuki Narukage


Solar flares are the largest explosive events in the solar system, and it is easy to imagine that such explosions generate shock waves that propagate in the solar corona. In 1960, a coronal shock wave was indirectly discovered in H-alpha, i.e., the intersection of a coronal shock wave and the chromosphere was observed as an H-alpha wave-like disturbances. This wave was named 'Moreton waves' after the discoverer. In the 1990s, solar observing satellites were launched and directly detected coronal shock waves in extreme ultraviolet and soft X-rays. Recently, coronal waves have also been imaged by ground based observations in radio and helium line. However, observations of shock waves were rare, because the shock wave signatures are much fainter than the solar flare and propagate very fast. The generation mechanism of coronal shock waves has not been made clear yet. In this presentation, I review the coronal shock waves observed in multi wavelength. And I also present our latest works of flare-associated shock waves observed with new telescopes, namely, Solar Magnetic Activity Research Telescope (SMART) at Hida observatory, and X-ray telescope (XRT) & Extreme-Ultraviolet Imaging Spectrometer (EIS) on board Hinode satellite.