Search Results - "Lyons, L. R."

Localized reconnection in the magnetotail driven by lobe flow channels: Global MHD simulation by Nishimura, Y., Lyons, L. R.

“…Recent ionospheric measurements suggest polar cap flow channels often trigger nightside auroral brightening. However, measurements were limited to the…”
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Identification of Auroral Zone Activity Driving Large‐Scale Traveling Ionospheric Disturbances by Lyons, L. R., Nishimura, Y., Zhang, S.‐R., Coster, A. J., Bhatt, A., Kendall, E., Deng, Y.

“…We have used all‐sky imaging to relate different types of auroral oval disturbances to large‐scale traveling ionospheric disturbances (LSTIDs). We selected…”
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Identifying the Driver of Pulsating Aurora by Nishimura, Y, Bortnik, J, Li, W, Thorne, R.M, Lyons, L.R, Angelopoulos, V, Mende, S.B, Bonnell, J.W, Le Contel, O, Cully, C, Ergun, R, Auster, U

“…Pulsating aurora, a spectacular emission that appears as blinking of the upper atmosphere in the polar regions, is known to be excited by modulated,…”
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Statistical properties of substorm auroral onset beads/rays by Nishimura, Y., Yang, J., Pritchett, P. L., Coroniti, F. V., Donovan, E. F., Lyons, L. R., Wolf, R. A., Angelopoulos, V., Mende, S. B.

“…Auroral substorms are often associated with optical ray or bead structures during initial brightening (substorm auroral onset waves). Occurrence probabilities…”
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Observational properties of dayside throat aurora and implications on the possible generation mechanisms by Han, D.‐S., Hietala, H., Chen, X.‐C., Nishimura, Y., Lyons, L. R., Liu, J.‐J., Hu, H.‐Q., Yang, H.‐G.

“…Observational properties of throat aurora are investigated in detail by using 7 year continuous auroral observations obtained at Yellow River Station (magnetic…”
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Relative contributions of large-scale and wedgelet currents in the substorm current wedge by Nishimura, Y., Lyons, L. R., Gabrielse, C., Weygand, J. M., Donovan, E. F., Angelopoulos, V.

“…We examined how much large-scale and localized upward and downward currents contribute to the substorm current wedge (SCW), and how they evolve over time,…”
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Coupling of dipolarization front flow bursts to substorm expansion phase phenomena within the magnetosphere and ionosphere by Lyons, L. R., Nishimura, Y., Xing, X., Runov, A., Angelopoulos, V., Donovan, E., Kikuchi, T.

“…Recent THEMIS spacecraft observations have shown longitudinally narrow, earthward moving, plasma sheet flow channels with large, abrupt magnetic field…”
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Influence of Auroral Streamers on Rapid Evolution of Ionospheric SAPS Flows by Gallardo‐Lacourt, Bea, Nishimura, Y., Lyons, L. R., Mishin, E. V., Ruohoniemi, J. M., Donovan, E. F., Angelopoulos, V., Nishitani, N.

“…Subauroral polarization streams (SAPS) often show large, rapid enhancements above their slowly varying component. We present simultaneous observations from…”
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Unsolved problems: Mesoscale polar cap flow channels' structure, propagation, and effects on space weather disturbances by Lyons, L. R., Nishimura, Y., Zou, Y.

“…Recent evidence indicates that the magnetosphere‐ionosphere system is frequently driven by dynamic mesoscale flow structures that are first seen near the…”
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Substorm triggering by new plasma intrusion: Incoherent-scatter radar observations by Lyons, L. R., Nishimura, Y., Shi, Y., Zou, S., Kim, H.-J., Angelopoulos, V., Heinselman, C., Nicolls, M. J., Fornacon, K.-H.

“…In the companion paper, we identified a repeatable sequence of events leading to substorm onset in THEMIS all‐sky imager observations: enhanced flows bring new…”
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Distinction between auroral substorm onset and traditional ground magnetic onset signatures by Lyons, L. R., Nishimura, Y., Donovan, E., Angelopoulos, V.

“…To evaluate whether ground magnetic responses traditionally viewed as signatures of substorm onset may be related to postonset auroral streamers rather than to…”
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Source Region and Propagation of Dayside Large‐Scale Traveling Ionospheric Disturbances by Nishimura, Y., Zhang, S. R., Lyons, L. R., Deng, Y., Coster, A. J., Moen, J. I., Clausen, L. B., Bristow, W. A., Nishitani, N.

“…We examined the source region of dayside large‐scale traveling ionospheric disturbances (LSTIDs) and their relation to cusp energy input. Aurora and total…”
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Do the Throat Auroras Create Polar Cap Patches? by Zhang, Duan, Zhang, Qing‐He, Oksavik, Kjellmar, Xu, Tong, Xing, Zan‐Yang, Lyons, L. R., Han, De‐Sheng, Zhang, Hong‐Bo, Ma, Yu‐Zhang, Hu, Ze‐Jun, Liu, Jian‐Jun, Wang, Yong, Wang, Xiang‐Yu

“…Throat auroras and polar cap patches are common phenomena in the polar ionosphere resulting from magnetosphere‐ionosphere coupling. A campaign was organized,…”
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Day-night coupling by a localized flow channel visualized by polar cap patch propagation by Nishimura, Y., Lyons, L. R., Zou, Y., Oksavik, K., Moen, J. I., Clausen, L. B., Donovan, E. F., Angelopoulos, V., Shiokawa, K., Ruohoniemi, J. M., Nishitani, N., McWilliams, K. A., Lester, M.

“…We present unique coordinated observations of the dayside auroral oval, polar cap, and nightside auroral oval by three all‐sky imagers, two Super Dual Auroral…”
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Structures of dayside whistler-mode waves deduced from conjugate diffuse aurora by Nishimura, Y., Bortnik, J., Li, W., Thorne, R. M., Ni, B., Lyons, L. R., Angelopoulos, V., Ebihara, Y., Bonnell, J. W., Le Contel, O., Auster, U.

“…We present simultaneous measurements of dayside diffuse aurora and whistler‐mode waves made by the South Pole all‐sky imager and two of the THEMIS spacecraft…”
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Formation of substorm Pi2: A coherent response to auroral streamers and currents by Nishimura, Y., Lyons, L. R., Kikuchi, T., Angelopoulos, V., Donovan, E., Mende, S., Chi, P. J., Nagatsuma, T.

“…Pi2 driving has been the subject of long standing debate involving magnetosphere‐ionosphere coupling. Using the THEMIS ground‐based all‐sky imager array, we…”
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Relations between multiple auroral streamers, pre-onset thin arc formation, and substorm auroral onset by Nishimura, Y., Lyons, L. R., Angelopoulos, V., Kikuchi, T., Zou, S., Mende, S. B.

“…Recent ground‐based imager observations have provided evidence of precursor auroral activity leading to substorm auroral onset, where the precursor is…”
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Multievent study of the correlation between pulsating aurora and whistler mode chorus emissions by Nishimura, Y., Bortnik, J., Li, W., Thorne, R. M., Chen, L., Lyons, L. R., Angelopoulos, V., Mende, S. B., Bonnell, J., Le Contel, O., Cully, C., Ergun, R., Auster, U.

“…A multievent study was performed using conjugate measurements of the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft…”
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Statistical relationships between enhanced polar cap flows and PBIs by Zou, Y., Nishimura, Y., Lyons, L. R., Donovan, E. F., Ruohoniemi, J. M., Nishitani, N., McWilliams, K. A.

“…Poleward boundary intensifications (PBIs) are auroral intensifications along the poleward boundary of the auroral oval and occur during all levels of…”
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Substorm onset and expansion phase intensification precursors seen in polar cap patches and arcs by Nishimura, Y., Lyons, L. R., Shiokawa, K., Angelopoulos, V., Donovan, E. F., Mende, S. B.

“…Localized, transient polar cap flows impinging on the poleward boundary of the nightside auroral oval have been suggested to precede poleward boundary…”
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