The seasonal and the altitudinal dpendence of the auroral particle acceleration region

Details The seasonal and the altitudinal dpendence of the auroral particle acceleration region The seasonal and the altitudinal dpendence of the auroral particle acceleration region

Dec 2001

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001agufmsm51b0826m&link_type=abstract

American Geophysical Union, Fall Meeting 2001, abstract #SM51B-0826

Other

2407 Auroral Ionosphere (2704), 2409 Current Systems (2708), 2451 Particle Acceleration, 2716 Energetic Particles, Precipitating

Scientific paper

Using the particle data obtained by the Akebono satellite, which observes at altitudes of 3,000-10,000km, the particle acceleration events, which are the dounward electron acceleration and UFI, have been investigated in latitudes, local times, altitudes, and seasons. Three high occurrence frequency regions (located at about 21MLT, 15MLT, and 9MLT) were found in the auroral region. The occurrence frequency and the total potential difference in each spot have different characteristics. The above seasonal dependences should closely relate to the seasonal dependence of the field-aligned currents at each region. At 15MLT, the occurrence frequency of the particle acceleration events in the summer hemisphere was higher than that in the winter hemisphere, and the total potential difference also becomes large in summer. This seasonal dependence is consistent with the seasonal dependence of the field-aligned current in this region [Fujii et al., 1981]. The field-aligned current system at 15MLT region is considered as the voltage generator. On the other hand, at 9MLT, the average potential difference did not depend on seasons. This tendency was not consistent with the seasonal dependence of the field-aligned current, which is higher in summer. At 21MLT, the occurrence frequency of the particle acceleration becomes high in the winter hemisphere, but no seasonal dependence of the total potential difference has been observed. The characteristic of the potential difference at 21MLT was consistent with the characteristic of the field-aligned current, which intensity has no seasonal dependence within the small-scale structure [Vickeray et al., 1986]. The parallel potential difference in 21MLT should relate to the small-scale field-aligned current, which is generated by the current generator. In addition, we have found that the existence altitude of the parallel potential difference has seasonal dependence. Parallel potential difference exists at high altitudes above 6,000km in summer, while they confined in low altitudes below 8,000km in winter. This tendency should relate to the seasonal variation of the ambient plasma density, which is expected to be low in winter. The relationship between the parallel potential difference, the field-aligned current and the plasma density will be discussed.

Affiliated with

Also associated with

No associations

Rating

The seasonal and the altitudinal dpendence of the auroral particle acceleration region does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The seasonal and the altitudinal dpendence of the auroral particle acceleration region, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The seasonal and the altitudinal dpendence of the auroral particle acceleration region will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1385948