Search Results - "Halford, A. J."

EMIC wave activity during geomagnetic storm and nonstorm periods: CRRES results by Halford, A. J., Fraser, B. J., Morley, S. K.

“…Electromagnetic ion cyclotron (EMIC) waves have been observed during geomagnetic storms and are thought to contribute to ring current and radiation belt…”
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Interplanetary shocks and the resulting geomagnetically induced currents at the equator by Carter, B. A., Yizengaw, E., Pradipta, R., Halford, A. J., Norman, R., Zhang, K.

“…Geomagnetically induced currents (GICs) caused by interplanetary shocks represent a serious space weather threat to modern technological infrastructure. The…”
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A Strong Correlation Between Relativistic Electron Microbursts and Patchy Aurora by Shumko, M., Gallardo‐Lacourt, B., Halford, A. J., Liang, J., Blum, L. W., Donovan, E., Murphy, K. R., Spanswick, E.

“…In this letter, we present the results of a conjunction between the Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX) satellite and a Time History…”
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EMIC waves and plasmaspheric and plume density: CRRES results by Halford, A. J., Fraser, B. J., Morley, S. K.

“…Electromagnetic ion cyclotron (EMIC) waves frequently occur during geomagnetic storms, specifically during the main phase and 3–6 days following the minimum…”
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Ion Injection Triggered EMIC Waves in the Earth's Magnetosphere by Remya, B., Sibeck, D. G., Halford, A. J., Murphy, K. R., Reeves, G. D., Singer, H. J., Wygant, J. R., Perez, G. Farinas, Thaller, S. A.

“…We present Van Allen Probe observations of electromagnetic ion cyclotron (EMIC) waves triggered solely due to individual substorm-injected ions in the absence…”
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The Effect of Compression Induced Chorus Waves on 10–100 s eV Electron Precipitation by Halford, A. J., Garcia‐Sage, K., Mann, I. R., Turner, D. L., Breneman, A. W.

“…On 7 January 2014, a solar storm erupted, which eventually compressed the Earth's magnetosphere leading to the generation of chorus waves. These waves enhanced…”
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A summary of the BARREL campaigns: Technique for studying electron precipitation by Woodger, L. A., Halford, A. J., Millan, R. M., McCarthy, M. P., Smith, D. M., Bowers, G. S., Sample, J. G., Anderson, B. R., Liang, X.

“…The Balloon Array for Radiation belt Relativistic Electron Losses (BARREL) studies the loss of energetic electrons from Earth's radiation belts. BARREL's array…”
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Observation of an Electron Microburst With an Inverse Time‐Of‐Flight Energy Dispersion by Shumko, M., Miyoshi, Y., Blum, L. W., Halford, A. J., Breneman, A. W., Johnson, A. T., Sample, J. G., Klumpar, D. M., Spence, H. E.

“…Interactions between whistler mode chorus waves and electrons are a dominant mechanism for particle acceleration and loss in the outer radiation belt. One form…”
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Simultaneous Precipitation of Sub‐Relativistic Electron Microburst and Pulsating Aurora Electrons by Namekawa, T., Mitani, T., Asamura, K., Miyoshi, Y., Hosokawa, K., Lessard, M., Moser, C., Halford, A. J., Sakanoi, T., Kawamura, M., Nose, M., Nomura, R., Teramoto, M., Shumko, M., Lynch, K. A., Jaynes, A. N., McHarg, M. G.

“…We have identified for the first time an energy‐time dispersion of precipitating electron flux in a pulsating aurora patch, ranging from 6.7 to 580 keV,…”
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Dependence of EMIC wave parameters during quiet, geomagnetic storm, and geomagnetic storm phase times by Halford, A. J., Fraser, B. J., Morley, S. K., Elkington, S. R., Chan, A. A.

“…As electromagnetic ion cyclotron (EMIC) waves may play an important role in radiation belt dynamics, there has been a push to better include them into global…”
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Association Between EMIC Wave Occurrence and Enhanced Convection Periods During Ion Injections by Remya, B., Sibeck, D. G., Ruohoniemi, J. M., Kunduri, B., Halford, A. J., Reeves, G. D., Reddy, R. V.

“…Electromagnetic ion cyclotron (EMIC) waves tend to occur during geomagnetic storms and solar wind pressure pulses. However, they have also been regularly…”
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Driving of Outer Belt Electron Loss by Solar Wind Dynamic Pressure Structures: Analysis of Balloon and Satellite Data by Breneman, A. W., Halford, A. J., Millan, R. M., Woodger, L. A., Zhang, X.‐J., Sandhu, J. K., Capannolo, L., Li, W., Ma, Q., Cully, C. M., Murphy, K. R., Brito, T., Elliott, S. S.

“…We present observations of ~10–60 min solar wind dynamic pressure structures that drive large‐scale coherent ~20–100 keV electron loss from the outer radiation…”
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Quantifying the Size and Duration of a Microburst‐Producing Chorus Region on 5 December 2017 by Elliott, S. S., Breneman, A. W., Colpitts, C., Pettit, J. M., Cattell, C. A., Halford, A. J., Shumko, M., Sample, J., Johnson, A. T., Miyoshi, Y., Kasahara, Y., Cully, C. M., Nakamura, S., Mitani, T., Hori, T., Shinohara, I., Shiokawa, K., Matsuda, S., Connors, M., Ozaki, M., Manninen, J.

“…Microbursts are impulsive (<1 s) injections of electrons into the atmosphere, thought to be caused by nonlinear scattering by chorus waves. Although attempts…”
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Star-Exoplanet Interactions: A Growing Interdisciplinary Field in Heliophysics by Garcia-Sage, K, Farrish, A O, Airapetian, V S, Alexander, D, Cohen, O, Domagal-Goldman, S, Dong, C, Gronoff, G, Halford, A J, Lazio, J, Luhmann, J G, Schwieterman, E, Sciola, A, Segura, A, Toffoletto, F, Vievering, J, Ahmed, Redyan, Bali, K, Chen, T Y, Rau, G

“…Traditionally, heliophysics is characterized as the study of the near-Earth space environment, where plasmas and neutral gases originating from the Earth, the…”
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Improved Space Weather Observations and Modeling for Aviation Radiation by Bain, H M, Onsager, T G, Mertens, C J, Copeland, K, Benton, E R, Clem, J, Mangeard, P-S, Green, J C, Guild, T B, Tobiska, W K, Shelton-Mur, K, Zheng, Y, Halford, A J, Carlson, S, Pulkkinen, A

“…In recent years there has been a growing interest from the aviation community for space weather radiation forecasts tailored to the needs of the aviation…”
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Comparison of the sensitivity of conventional cytology and the ThinPrep Imaging System for 1,083 biopsy confirmed high-grade squamous lesions by Halford, J. A., Batty, T., Boost, T., Duhig, J., Hall, J., Lee, C., Walker, K.

“…Liquid‐based cytology continues to be utilized as an adjunct to conventional cytology in most Australian laboratories, even though a direct‐to‐vial ThinPrep…”
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The Space Physics Environment Data Analysis System (SPEDAS) by Angelopoulos, V., Cruce, P., Drozdov, A., Grimes, E. W., Hatzigeorgiu, N., King, D. A., Larson, D., Lewis, J. W., McTiernan, J. M., Roberts, D. A., Russell, C. L., Hori, T., Kasahara, Y., Kumamoto, A., Matsuoka, A., Miyashita, Y., Miyoshi, Y., Shinohara, I., Teramoto, M., Faden, J. B., Halford, A. J., McCarthy, M., Millan, R. M., Sample, J. G., Smith, D. M., Woodger, L. A., Masson, A., Narock, A. A., Asamura, K., Chang, T. F., Chiang, C.-Y., Kazama, Y., Keika, K., Matsuda, S., Segawa, T., Seki, K., Shoji, M., Tam, S. W. Y., Umemura, N., Wang, B.-J., Wang, S.-Y., Redmon, R., Rodriguez, J. V., Singer, H. J., Vandegriff, J., Abe, S., Nose, M., Shinbori, A., Tanaka, Y.-M., UeNo, S., Andersson, L., Dunn, P., Fowler, C., Halekas, J. S., Hara, T., Harada, Y., Lee, C. O., Lillis, R., Mitchell, D. L., Argall, M. R., Bromund, K., Burch, J. L., Cohen, I. J., Galloy, M., Giles, B., Jaynes, A. N., Le Contel, O., Oka, M., Phan, T. D., Walsh, B. M., Westlake, J., Wilder, F. D., Bale, S. D., Livi, R., Pulupa, M., Whittlesey, P., DeWolfe, A., Harter, B., Lucas, E., Auster, U., Bonnell, J. W., Cully, C. M., Donovan, E., Ergun, R. E., Frey, H. U., Korth, H., McFadden, J. P., Nishimura, Y., Plaschke, F., Robert, P., Turner, D. L., Weygand, J. M., Candey, R. M., Johnson, R. C., Kovalick, T., Liu, M. H., McGuire, R. E., Breneman, A., Kersten, K., Schroeder, P.

“…With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the…”
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Understanding Quiet and Storm Time EMIC Waves—Van Allen Probes Results by Remya, B., Halford, A. J., Sibeck, D. G., Murphy, K. R., Fok, M.‐C.

“…Geomagnetic indices have been used as a proxy for studying electromagnetic ion cyclotron (EMIC) wave occurrences under different geomagnetic conditions…”
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Drift Phase Structure Implications for Radiation Belt Transport by O'Brien, T. P., Green, J. C., Halford, A. J., Kwan, B. P., Claudepierre, S. G., Ozeke, Louis G.

“…We examine drift phase structure in the electron radiation belt observations to differentiate radial transport mechanisms. Impulsive electrostatic or…”
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Latitudinal and seasonal variations of quasiperiodic and periodic VLF emissions in the outer magnetosphere by Engebretson, M. J., Posch, J. L., Halford, A. J., Shelburne, G. A., Smith, A. J., Spasojević, M., Inan, U. S., Arnoldy, R. L.

“…We have analyzed ELF‐VLF receiver and search coil magnetometer data from five Antarctic stations from 1998 and 1999 to study quasiperiodic emissions (QPs) and…”
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