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Single-event upsets in the Cluster and Double Star Digital Wave Processor instruments

Walker, S. N.; Yearby, K. H.; Balikhin, M.

Radiation-induced upsets are an important issue for electronic circuits operating in space. Upsets due to solar protons, trapped protons, and galactic cosmic rays are frequently observed. Modeling the expected frequency of upsets is a necessary part of the design process for space hardware. The Cluster and Double Star spacecraft were respectively …

A major solar eruptive event in July 2012: Defining extreme space weather scenarios

Galvin, A. B.; Baker, D. N.; Li, X. +4 more

key goal for space weather studies is to define severe and extreme conditions that might plausibly afflict human technology. On 23 July 2012, solar active region 1520 (~141°W heliographic longitude) gave rise to a powerful coronal mass ejection (CME) with an initial speed that was determined to be 2500 ± 500 km/s. The eruption was directed away fr…

Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed?

Galvin, A. B.; Zheng, Yihua; Pulkkinen, Antti +7 more

Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 ast…

An operational software tool for the analysis of coronagraph images: Determining CME parameters for input into the WSA-Enlil heliospheric model

de Koning, C. A.; Pizzo, V.; Millward, G. +1 more

Coronal mass ejections (CMEs)—massive explosions of dense plasma that originate in the lower solar atmosphere and propagate outward into the solar wind—are the leading cause of significant space weather effects within Earth's environment. Computational models of the heliosphere such as WSA-Enlil offer the possibility of predicting whether a given …

On the performance of global magnetohydrodynamic models in the Earth's magnetosphere

Raeder, J.; Wiltberger, M.; Palmroth, M. +5 more

We study the performance of four magnetohydrodynamic models (BATS-R-US, GUMICS, LFM, OpenGGCM) in the Earth's magnetosphere. Using the Community Coordinated Modeling Center's Run-on-Request system, we compare model predictions with magnetic field measurements of the Cluster, Geotail and Wind spacecraft during a multiple substorm event. We also com…

Forecasting propagation and evolution of CMEs in an operational setting: What has been learned

Mays, M. L.; Zheng, Yihua; Macneice, Peter +8 more

of the major types of solar eruption, coronal mass ejections (CMEs) not only impact space weather, but also can have significant societal consequences. CMEs cause intense geomagnetic storms and drive fast mode shocks that accelerate charged particles, potentially resulting in enhanced radiation levels both in ions and electrons. Human and technolo…

Ensemble forecasting of coronal mass ejections using the WSA-ENLIL with CONED Model

Odstrcil, D.; Taktakishvili, A.; Pulkkinen, A. +3 more

The combination of the Wang-Sheeley-Arge (WSA) coronal model, ENLIL heliospherical model version 2.7, and CONED Model version 1.3 (WSA-ENLIL with CONED Model) was employed to form ensemble forecasts for 15 halo coronal mass ejections (halo CMEs). The input parameter distributions were formed from 100 sets of CME cone parameters derived from the CO…

The SCORE Scale: A Coronal Mass Ejection Typification System Based On Speed

Zheng, Yihua; Taktakishvili, Aleksandre; Hesse, Michael +4 more

On the probability of occurrence of extreme space weather events

Riley, Pete

By virtue of their rarity, extreme space weather events, such as the Carrington event of 1859, are difficult to study, their rates of occurrence are difficult to estimate, and prediction of a specific future event is virtually impossible. Additionally, events may be extreme relative to one parameter but normal relative to others. In this study, we…

L* neural networks from different magnetic field models and their applicability

Yu, Yiqun; Zaharia, Sorin; Koller, Josef +1 more

The third adiabatic invariant L* plays an important role in modeling and understanding the radiation belt dynamics. The typical way to numerically calculate the L* value follows the method described by Roederer (1970), which is just a line integration method that is computationally slow and expensive. This work describes the application of an arti…