Seminars

Lecturer: Satoshi Kimura (Tohoku)
Date: 2008-12-17 10:30
Place: Aniara

Observation plan for flickering aurora using high-speed CCD camera at Esrange, Sweden

Satoshi Kimura
Planetary Plasma and Atmospheric Research Center
Graduate School of Science
Tohoku University
Japan

Abstract
Since flickering aurora was first well defined by Beach et al. [1968],
several works on flickering aurora have been reported.
Optical observations of flickering aurora have so far been carried out using TV cameras
or photometers in the past [e.g. Oguti, 1978; Berkey et al., 1980; Sakanoi et al., 2004, 2005].
They showed the basic characteristics of flickering aurora.
The frequencies of the modulation are usually 10+/-3 Hz and the width and vertical length of
each flickering column are in the ranges of 1-10 km and >40 km, respectively.
By coordinated ground-based optical imaging observations and sounding rocket particle measurements,
intensity variations of flickering aurora are found to be produced by periodic modulations
of precipitating electron fluxes. Temerin et al. [1986, 1993] proposed a model
of field-aligned electron flux acceleration by electromagnetic ion cyclotron (EMIC) waves,
which produces flickering aurora.
It is said that flickering aurora has also high frequency modulations while
the ordinary frequencies are 10+/-3 Hz. It is , however, difficult to detect the high frecency
modulations using usual optical equipments because of their sensitivity.
Flickering aurora with high frequencies is expected to be observed
with our newly developed system, and the condition for
producing flickering aurora will be more deeply understood.
So, we installed EMCCD camera for flickering aurora observation at Esrange.
In this presentation, our strategy for the observation will be given.


Created 2008-12-15 13:15:29 by Mats Holmström
Last changed 2008-12-15 13:15:29 by Mats Holmström