HR: 0800h
AN: SH51A-0262    [Abstracts]
TI: A Catalog of Halo Coronal Mass Ejections from SOHO
AU: Gopalswamy, N
EM: gopals@ssedmail.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 695.0, Greenbelt, MD 20771, United States
AU: Yashiro, S
EM: yashiro@ssedmail.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 695.0, Greenbelt, MD 20771, United States
AU: Yashiro, S
EM: yashiro@ssedmail.gsfc.nasa.gov
AF: Catholic University of America, 620 Michigan Ave. NE, Washington, DC 20064, United States
AU: Michalek, G
EM: michalek@ssedmail.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 695.0, Greenbelt, MD 20771, United States
AU: Michalek, G
EM: michalek@ssedmail.gsfc.nasa.gov
AF: Catholic University of America, 620 Michigan Ave. NE, Washington, DC 20064, United States
AU: Xie, H
EM: hong.xie@ssedmail.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 695.0, Greenbelt, MD 20771, United States
AU: Xie, H
EM: hong.xie@ssedmail.gsfc.nasa.gov
AF: Catholic University of America, 620 Michigan Ave. NE, Washington, DC 20064, United States
AU: Vourlidas, A
EM: vourlidas@nrl.navy.mil
AF: Naval Research Lab, 4555 Overlook Avenue, SW, Washington, DC 20375, United States
AU: Howard, R A
EM: russ.howard@nrl.navy.mil
AF: Naval Research Lab, 4555 Overlook Avenue, SW, Washington, DC 20375, United States
AU: * Schmidt, J
EM: jschmidt@ssedmail.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 695.0, Greenbelt, MD 20771, United States
AB: Halo coronal mass ejections (CMEs) have become one of the important subsets of CMEs, thanks to the extensive data accumulated by the Solar and Heliospheric Observatory (SOHO) mission. Halo CMEs are inherently more energetic on the average, so they are important for producing geomagnetic storms and solar energetic particle events (Gopalswamy et al., 2007). One of the key aspects halo CMEs is their source location, which decides whether the halo is symmetric or not. When the source is closer to the solar limb, the CMEs tend to become asymmetric halos or partial halos. Halos with their sources nearer to the limb are also the fastest (because of projection effects), but are less geoeffective due to the glancing blow they deliver to Earthfs magnetosphere. Thus, providing source information to all halo CMEs in a separate catalog is useful information in selecting candidate geoeffective CMEs. The second important quantity of CMEs is the space speed, which decides the arrival time of CMEs at Earth. Since CMEs change their width during their early evolution, it is not easy to correct for the projection effects from the geometry of eruption. One way of correcting for projection effects is to use a cone model for CMEs. There are at least 3 published cone models, all of them seem to remove the projection effects reasonably well. The geometric parameters of the cone are determined using different methods in each model. Here we use the model by Xie et al. (2004), which has generally less restrictions, and hence can be applied to more number of halos. This paper provides a brief description of the catalog of halo CMEs, which resides at the CDAW Data Center, NASA Goddard Space Flight Center, Greenbelt, MD. The catalog enhances the existing data services at the CDAW Data Center, which participates in the Virtual Solar Observatory. Work supported by NASAfs Virtual Observatories for Solar and Space Physics Data Program. References Gopalswamy et al., JGR, 112, A06112, doi:10.1029/2006JA012149, 2007 Xie et al. JGR, 109, A03109, doi: 10.1029/2003JA010226, 2004
UR: http://cdaw.gsfc.nasa.gov/CME_list/
DE: 0525 Data management
DE: 7513 Coronal mass ejections (2101)
DE: 7519 Flares
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting