Abstract
A compact flare was observed with Nobeyama Radioheliograph (NoRH) slightly behind the west limb on 2011 March 10. The microwave peak flux values at 17 and 34 GHz were about 210 and 133 sfu, respectively. From the correlation between the 17 GHz peak flux and the GOES 1-8 Å soft X-ray peak flux, M1.5-class is expected for this microwave flux. However, only the B1-level enhancement was detected in the GOES 1-8 Å soft X-ray light curve on the C1-level background during the flare period. In addition to microwaves, Suzaku detected hard X-ray emissions, even in the energy range above 100 keV. It is clear that high-energy electrons were effectively produced in this flare, while the thermal emission was very weak. Why did this flare have this unique feature? The following two cases are considered. One is the case that a magnetic trap for electrons works effectively, and that each electron continues to emit microwaves in its relatively long lifetime. The other is that the magnetic field around the looptop region is intense, and relatively a large number of lower-energy electrons emit microwaves. Considering the observational facts, such as the short duration and the small flare loop, the latter case is more plausible.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call