국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	Galactic Cosmic Ray Intensity Response to Interplanetary Coronal Mass Ejections/Magnetic Clouds in 1995-2009
저자	Richardson, I. G.;; Cane, H. V.
Keyword	CORONAL MASS EJECTION;; GALACTIC COSMIC RAYS;; INTERPLANETARY MAGNETIC FIELDS;; MAGNETIC CLOUDS;; MAGNETIC FIELDS;; PLASMAS (PHYSICS); SOLAR CYCLES;; SOLAR WIND
URL	http://dx.doi.org/10.1007/s11207-011-9774-x
보고서번호	GSFC.JA.5412.2011
발행년도	2011
출처	NTRS (NASA Technical Report Server)
ABSTRACT	We summarize the response of the galactic cosmic ray (CGR) intensity to the passage of the more than 300 interplanetary coronal mass ejections (ICMEs) and their associated shocks that passed the Earth during 1995-2009, a period that encompasses the whole of Solar Cycle 23. In approx.80% of cases, the GCR intensity decreased during the passage of these structures, i.e., a "Forbush decrease" occurred, while in approx.10% there was no significant change. In the remaining cases, the GCR intensity increased. Where there was an intensity decrease, minimum intensity was observed inside the ICME in approx.90% of these events. The observations confirm the role of both post-shock regions and ICMEs in the generation of these decreases, consistent with many previous studies, but contrary to the conclusion of Reames, Kahler, and Tylka (Astrophys. 1. Lett. 700, L199, 2009) who, from examining a subset of ICMEs with flux-rope-like magnetic fields (magnetic clouds) argued that these are "open structures" that allow free access of particles including GCRs to their interior. In fact, we find that magnetic clouds are more likely to participate in the deepest GCR decreases than ICMEs that are not magnetic clouds.