Outflow of low-energy O+ ion beams observed during periods without   substorms

doi:10.5194/angeo-33-333-2015

CORC > 北京大学 > 地球与空间科学学院

	Outflow of low-energy O+ ion beams observed during periods without substorms
	Parks, G. K. ; Lee, E. ; Fu, S. Y. ; Fillingim, M. ; Dandouras, I. ; Cui, Y. B. ; Hong, J. ; Reme, H.
刊名	ANNALES GEOPHYSICAE
	2015
关键词	Magnetospheric physics Magnetosphere-ionosphere interactions PLASMA SHEET DYNAMICS POLAR-CAP HIGH-ALTITUDE CENTRIFUGAL ACCELERATION GROWTH-PHASE OXYGEN IONS MAGNETOSPHERE MAGNETOTAIL ENERGIZATION IONOSPHERE
DOI	10.5194/angeo-33-333-2015
英文摘要	Numerous observations have shown that ions flow out of the ionosphere during substorms with more fluxes leaving as the substorm intensity increases (Wilson et al., 2004). In this article we show observations of low-energy (few tens of electron volts) ionospheric ions flowing out periods without substorms, determined using the Wideband Imaging Camera (WIC) and Auroral Electrojet (AE) indices. We use Cluster ion composition data and show the outflowing ions are field-aligned H+, He+ and O+ beams accelerated to energies of similar to 40-80 eV, after correcting for spacecraft potential. The estimated fluxes of the low-energy O+ ions measured at similar to 20 000 km altitude are > 10(3)-10(5) cm(-2) s. Assuming the auroral oval is the source of the escaping ions, the measured fluxes correspond to a flow rate of similar to 10(19)-10(21) ions s(-1) leaving the ionosphere. However, periods without substorms can persist for hours suggesting the low-energy ions flowing out during these times could be a major source of the heavy ion population in the plasma sheet and lobe.; NASA [NNX11AD49G-2/15]; BK21 Plus Program; Basic Science Research Program through the National Research Foundation - Ministry of Education of Korea [NRF-2013R1A1A2010711]; SCI(E); ARTICLE; parks@ssl.berkeley.edu; 3; 333-344; 33
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/421273]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Parks, G. K.,Lee, E.,Fu, S. Y.,et al. Outflow of low-energy O+ ion beams observed during periods without substorms[J]. ANNALES GEOPHYSICAE,2015.
APA	Parks, G. K..,Lee, E..,Fu, S. Y..,Fillingim, M..,Dandouras, I..,...&Reme, H..(2015).Outflow of low-energy O+ ion beams observed during periods without substorms.ANNALES GEOPHYSICAE.
MLA	Parks, G. K.,et al."Outflow of low-energy O+ ion beams observed during periods without substorms".ANNALES GEOPHYSICAE (2015).