Dayside Magnetospheric and Ionospheric Responses to a Foreshock Transient on 25 June 2008: 1. FLR Observed by Satellite and Ground-Based Magnetometers

• Published in: Journal of Geophysical Research: Space Physics
• Main Authors: Shen, Xiao-Chen, Shi, Quanqi, Wang, Boyi, Zhang, Hui, Hudson, Mary K., Nishimura, Yukitoshi, Hartinger, Michael D., Tian, Anmin, Zong, Qiu-Gang, Rae, I. J., Degeling, Alexander W.
• Other Authors: Electrical and Computer Engineering
• Format: Text
• Language: English
• Published: 2018
• Subjects: foreshock transient; ULF wave; FLR; Pc5 wave; Greenland; Norway; Tromso; Auster; Mende; Rae; University of Tromso
• Online Access: http://hdl.handle.net/10919/93504; https://doi.org/10.1029/2018JA025349

As one type of driver of magnetospheric Alfven waves, foreshock transients have received less attention than, for example, the Kelvin-Helmholtz instability, discrete and broadband frequency solar wind dynamic pressure oscillations, and interplanetary shocks. Previous works show that foreshock transients can induce both Alfven mode and compressional mode Pc 3-5 ULF waves inside the magnetosphere. However, to our knowledge, none of these reported Pc 3-5 waves, induced by foreshock transients, are proved to be localized in the magnetosphere. In this paper, using in situ and ground-based observations, we report the generation of localized magnetospheric compressional waves and field line resonances (FLRs) by a foreshock transient. Both the foreshock transient and Pc 5 ULF waves were found on the duskside; while on the morning side of the magnetosphere, no clear wave signatures were captured. Our results demonstrate that in addition to the global effects of foreshock transients on the magnetosphere reported earlier, foreshock transients can also generate localized magnetospheric responses in the Pc 5 range with clear dawn-dusk asymmetry. A suite of eight dayside spacecraft plus ground magnetometer measurements make possible the determination of the foreshock transient driver and dawn-dusk asymmetry of the magnetospheric response not previously reported with such a complete data set. NASA [NAS5-02099]; NSF [AGS-1004814, PLR-1341359]; National Natural Science Foundation of China [41574157, 41322031, 41628402]; STFC [ST/N000722/1]; NERC [NE/L007495/1, NE/P017150/1, NE/P017185/1]; [NSFAGS-1352669]; [NASANNX17AD35G] We acknowledge NASA contract NAS5-02099 and V. Angelopoulos for use of data from the THEMIS Mission (http://themis.ssl.berkeley.edu/data/themis/). Specifically, C. W. Carlson and J. P. McFadden for use of ESA data, K. H. Glassmeier, U. Auster, and W. Baumjohann for the use of FGM data provided under the lead of the Technical University of Braunschweig, S. Mende and C. T. Russell for use of the GMAG data and NSF for support through grant AGS-1004814, TromsO Geophysical Observatory, University of TromsO, Norway for use of the Greenland and Norway magnetometer data, Erik Steinmetz, Augsburg College for the use of GMAG data. NOAA GOES data are obtained from the website: https://cdaweb.sci.gsfc.nasa.gov/index.html/. This work is supported by the National Natural Science Foundation of China (grants 41574157, 41322031, and 41628402) H. Zhang is partially supported by NSFAGS-1352669. M. D. Hartinger is supported by NASANNX17AD35G. I. J. Rae is supported by STFC grant ST/N000722/1, and NERC grants NE/L007495/1, NE/P017150/1, and NE/P017185/1. The work by YN and BW was supported by NSF grant PLR-1341359. Thanks to the NCAR High Altitude Observatory for hospitality to X. C. Shen. We are grateful to the International Space Science Institute-Beijing for supporting the international teams "Dayside Transient Phenomena and Their Impact on the Magnetosphere-Ionosphere" and "Multiple-instrument observations and simulations of the dynamical processes associated with polar cap patches/aurora and their associated scintillations".