Properties of DH Type II Radio Bursts and Their Space Weather Implications

Gopalswamy, N ; Makela, P

关键词: SOLAR RADIO BURSTS;    TYPE 2 BURSTS;    ENERGETIC PARTICLES;    CORONAL MASS EJECTION;    SOLAR CYCLES;    SPACE WEATHER;    SUN;    WIND/GGS SPACECRAFT;    STEREO (OBSERVATORY);    GOES SATELLITES;   

RP-ID  :  GSFC-E-DAA-TN71305

学科分类：天文学(综合)

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

We report on the properties of type II radio bursts observed by the Radio and Plasma Wave Experiment (WAVES) onboard the Wind spacecraft over the past two solar cycles. We confirm that the associated coronal mass ejections (CMEs) are fast and wide, more than half the CMEs being halos. About half of the type II bursts extend down to 0.5M hertz, corresponding to a heliocentric distance of tens of solar radii. The DH (Decametric-Hectometric) type II bursts are mostly confined to the active region belt and their occurrence rate follows the solar activity cycle. Type II bursts occurring on the western hemisphere of the Sun and extending to lower frequencies are good indicators of a solar energetic particle event.