caa a22 4500 445346140 CHVBK 20180317142829.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s11207-011-9774-x doi (NATIONALLICENCE)springer-10.1007/s11207-011-9774-x Galactic Cosmic Ray Intensity Response to Interplanetary Coronal Mass Ejections/Magnetic Clouds in 1995 - 2009 [Elektronische Daten] [I. Richardson, H. Cane] 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 ∼ 80% of cases, the GCR intensity decreased during the passage of these structures, i.e., a "Forbush decrease” occurred, while in ∼ 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 ∼ 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. J. 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. Springer Science+Business Media B.V., 2011 Interplanetary coronal mass ejections nationallicence Magnetic clouds nationallicence Cosmic rays nationallicence Solar wind plasma nationallicence Interplanetary magnetic field nationallicence Coronal mass ejections nationallicence Richardson I. Code 661, NASA/Goddard Space Flight Center, 20771, Greenbelt, MD, USA aut Cane H. Code 661, NASA/Goddard Space Flight Center, 20771, Greenbelt, MD, USA aut Solar Physics Springer Netherlands 270/2(2011-06-01), 609-627 0038-0938 270:2<609 2011 270 11207 https://doi.org/10.1007/s11207-011-9774-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11207-011-9774-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Richardson I. Code 661, NASA/Goddard Space Flight Center, 20771, Greenbelt, MD, USA aut NATIONALLICENCE 700 1- Cane H. Code 661, NASA/Goddard Space Flight Center, 20771, Greenbelt, MD, USA aut NATIONALLICENCE 773 0- Solar Physics Springer Netherlands 270/2(2011-06-01), 609-627 0038-0938 270:2<609 2011 270 11207 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer