The Role of Peak Temperatures in Solar X-Ray Flare Associations with CME Speeds and Widths and in Flare Size Distributions

Abstract

Abstract Recently, we reported that solar X-ray flares with relatively low peak (0.05–0.3 nm)/(0.1–0.8 nm) ratios R, a proxy for peak flare temperature T, were preferentially associated not only with solar energetic (E > 10 MeV) particle (SEP) events, but also with fast (V cme ≥ 1000 km s−1) coronal mass ejections (CMEs) that produce the SEP events. Flares associated with a characteristic CME speed V cme range from small and cool to large and hot, and cooler X-ray flares were preferentially associated with broader CME widths. Here we increase the list of analyzed Geostationary Operational Environmental Satellite flares from the previous 450 to 588 and validate the earlier results with flare peak X-ray temperatures T from the TEBBS (Temperature and Emission measure-based Background Subtraction) method catalog. Power-law size distributions of flare peak fluxes F p are increasingly steeper for X-ray flares with (1) fast (V cme ≥ 1000 km s−1); (2) slow (V cme < 1000 km s−1); and (3) no CMEs; in each case flares of larger F p are characteristically hotter. The power-law size distribution of SEP event peak intensities I p is flatter than any of the X-ray F p distributions or a distribution formed from the product of the steep SEP I p dependence on V cme and the V cme number distributions.