|
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ПсковГУ |
||
Comparative characteristics of nighttime auroral precipitation under extreme levels of magnetic activityтезисы доклада
- Авторы: Vorobjev V.G., Yagodkina O.I., Antonova E.E.
- Сборник: Physics of Auroral Phenomena 48th Annual Seminar Abstracts
- Тезисы
- Год издания: 2025
- Место издания: Polar Geophysical Institute
- Первая страница: 27
- Последняя страница: 27
- Аннотация: Observations from DMSP F9 spacecraft in the pre-midnight MLT sector were used to examine latitudinal profiles of auroral ion and electron precipitation during magnetic calm and in the time of giant magnetic storm on March 13- 14, 1989. To compare the characteristics of the precipitation, the position of the maximum energy flux (Fi) of precipitating ions was used. The latitude of the maximum Fi is considered as the equatorial boundary of isotropic auroral precipitation (BIP). The characteristics of both ion and electron precipitation were analyzed in terms of the ion pressure (Pi) and the intensity of 557.7 nm emission (I5577) correspondingly. The average energy of precipitating particles in the area of auroral precipitation changed insignificantly, so latitudinal profiles of Pi and I5577 are similar to the that of Fi and Fe, respectively. The maximum of Pi almost exactly coincides with the position of the BIP. Under calm geomagnetic conditions, BIP is usually observed at corrected geomagnetic latitudes of 65°±1° CGL, and the Pimax value is approximately 0.5 - 1.0 nPa. With increasing magnetic activity, the BIP shifted equatorward and about at the maximum of the magnetic storm on March 14, 1989 (Dst=-583 nT, AL=-551 nT) was observed at the latitude Φ′BIP = 50.2° CGL with a level of Pi-max=20.0 nPa. The latitudinal position of the Pi-max with correlation coefficient r=0.81 described by the regression equation Φ'BIP = 66.46 – 0.0055|AL| − 5.43*10-7 AL2 + 0.026 Dst. The value of Pimax shows a distinct tendency to increase with decreasing of latitude. The method of epoch superposition relative to the BIP was used to construct average latitudinal profiles of ion and electron precipitation for the F9 spacecraft passes in which the BIP position was observed at latitudes Φ'BIP
- Добавил в систему: Воробьев Вячеслав Георгиевич