Upward propagating high-frequency Alfven waves as identified from   dynamic wave-like spicules observed by SOT on Hinode

doi:10.1051/0004-6361/200810777

CORC > 北京大学 > 地球与空间科学学院

	Upward propagating high-frequency Alfven waves as identified from dynamic wave-like spicules observed by SOT on Hinode
	He, J.S. ; Tu, C.Y. ; Marsch, E. ; Guo, L.J. ; Yao, S. ; Tian, H.
刊名	astronomy astrophysics
	2009
关键词	waves Sun: chromosphere Sun: transition region Sun: solar wind SOLAR OPTICAL TELESCOPE MAGNETOHYDRODYNAMIC TURBULENCE CORONAL HOLES WIND ACCELERATION PHOTOSPHERE GENERATION MISSION DRIVEN MODEL
DOI	10.1051/0004-6361/200810777
英文摘要	Aims. We identify high-frequency Alfven waves propagating upward in the solar chromosphere and transition region from observation by Solar Optical Telescope (SOT) onboard Hinode. Methods. The spicule shape is enhanced through application of a normal radial gradient filter and an un-sharp mask on the images taken by SOT. The displaced position of the spicule is at each height obtained by tracing the maximum intensity after image processing. The dominant wave period is obtained by the FFT method applied to the time variations of the displaced position at a certain height. The phase speed is estimated with the help of a cross-correlation analysis of two temporal sequences of the displaced positions at two heights along the spicule. Results. We find in four cases that the spicules are modulated by high-frequency (>= 0.02 Hz) transverse fluctuations. Such fluctuations are suggested to be Alfven waves that propagate upward along the spicules with phase speed ranges from 50 to 150 km s(-1). Three of the modulated spicules show clear wave-like shapes with short wavelengths less than 8 Mm. Conclusions. Our work identified directly upward propagation of Alfven waves in the solar chromosphere and transition region. In addition to the recently reported Alfven waves with very long wavelength and wave period, we find here four examples of Alfven waves with shorter wavelengths and periods. These findings shed new light on the wave origin and on coronal and solar-wind heating.; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000265097300024&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 ; Astronomy & Astrophysics; SCI(E); EI; 58; ARTICLE; 2; 525-535; 497
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/311293]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	He, J.S.,Tu, C.Y.,Marsch, E.,et al. Upward propagating high-frequency Alfven waves as identified from dynamic wave-like spicules observed by SOT on Hinode[J]. astronomy astrophysics,2009.
APA	He, J.S.,Tu, C.Y.,Marsch, E.,Guo, L.J.,Yao, S.,&Tian, H..(2009).Upward propagating high-frequency Alfven waves as identified from dynamic wave-like spicules observed by SOT on Hinode.astronomy astrophysics.
MLA	He, J.S.,et al."Upward propagating high-frequency Alfven waves as identified from dynamic wave-like spicules observed by SOT on Hinode".astronomy astrophysics (2009).