Space, time and velocity association of successive coronal mass ejections
Por:
Lara, Alejandro, Gopalswamy, Nat, Niembro, Tatiana, Perez-Enriquez, Roman, Yashiro, Seiji
Publicada:
17 mar 2020
Resumen:
Aims. Our aim is to investigate the possible physical association
between consecutive coronal mass ejections (CMEs).Methods. Through a
statistical study of the main characteristics of 27 761 CMEs observed by
SOHO/LASCO during the past 20 years.Results. We found the waiting time
(WT) or time elapsed between two consecutive CMEs is < 5 h for 59% and
< 25 h for 97% of the events, and the CME WTs follow a Pareto Type IV
statistical distribution. The difference of the position-angle of a
considerable population of consecutive CME pairs is less than 30
degrees, indicating the possibility that their source locations are in
the same region. The difference between the speed of trailing and
leading consecutive CMEs follows a generalized Student t-distribution.
The fact that the WT and the speed difference have heavy-tailed
distributions along with a detrended fluctuation analysis shows that the
CME process has a long-range dependence. As a consequence of the
long-range dependence, we found a small but significative difference
between the speed of consecutive CMEs, with the speed of the trailing
CME being higher than the speed of the leading CME. The difference is
largest for WTs < 2 h and tends to be zero for WTs > 10 h, and it is
more evident during the ascending and descending phases of the solar
cycle. We suggest that this difference may be caused by a drag force
acting over CMEs closely related in space and time.Conclusions. Our
results show that the initiation and early propagation of a significant
population of CMEs cannot be considered as a ``pure'' stochastic
process; instead they have temporal, spatial, and velocity relationship.
Filiaciones:
Lara, Alejandro:
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City, DF, Mexico
Catholic Univ Amer, Washington, DC 20064 USA
Gopalswamy, Nat:
NASA, GSFC, Greenbelt, MD USA
Niembro, Tatiana:
Smithsonian Astrophys Observ, Cambridge, MA USA
Perez-Enriquez, Roman:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Queretaro, Mexico
Yashiro, Seiji:
Catholic Univ Amer, Washington, DC 20064 USA
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