Open AccessInterplanetary magnetic field control of dayside ion conics
Author(s) -
Miyake W.,
Mukai T.,
Kaya N.
Publication year - 2000
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2000ja900082
Subject(s) - physics , ion , magnetosphere , noon , cusp (singularity) , interplanetary magnetic field , convection , local time , atomic physics , geophysics , astrophysics , solar wind , magnetic field , atmospheric sciences , geometry , meteorology , statistics , mathematics , quantum mechanics
Ion conics are frequently observed around the dayside cusp/cleft region and are supposed to be energized by an input of energy from the dayside magnetospheric boundary region. We examined possible influence of the interplanetary magnetic field (IMF) on dayside ion conics observed by the polar‐orbiting Exos D (Akebono) satellite. We found the effect of B y and B z components on the energy flux and occurrence frequency of ion conics. Ion conics are more energetic and more frequently observed when B z is negative and the magnitude of B y is large. The B z effect is likely to be attributed to the change in energy input to the ion energization region. The B y effect may be also due to the increased energy input to the cusp/cleft region during large B y period, suggesting that a reconnection‐related energy input is responsible for dayside ion energization. An alternative interpretation of the B y effect is that the convection pattern may affect the residence time in the ion energization region and therefore the efficiency of ion energization. We found that the polarity of B y controls asymmetrical magnetic local time distribution of ion conics around the local noon, which is attributed to a possible effect of convection pattern on dayside ion energization.