Solar Energetic Proton Access to the Magnetosphere During the 10–14 September 2017 Particle Event

O’Brien, T. P.; Mazur, J. E.; Looper, M. D.

doi:10.1029/2018sw001960

Cited by 22 publications

(27 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, rapid changes in the terrestrial magnetic field environment caused strong geomagnetically induced currents, a phenomenon that can damage critical technological infrastructures that contain ground‐based conducting systems, such as power grids, railways, telecommunication cables, and oil and gas pipelines (Clilverd et al., 2018; Dimmock et al., 2019; Piersanti et al., 2019). The SEPs, which were identified to enter the magnetosphere, likewise increased the likelihood of failures in spacecraft electronics (O'Brien et al., 2018), and on the International Space Station, the Moon, and Mars, increased radiation doses were observed (Berger et al., 2018; Hassler et al., 2018; Schwadron et al., 2018).…”

Section: Solar Storms Of September 2017 and Their Effects At Earth Anmentioning

confidence: 99%

Effects of the 10 September 2017 Solar Flare on the Density and Composition of the Thermosphere of Mars

et al. 2020

View full text Add to dashboard Cite

The effects of solar flares on the upper atmosphere of Mars are large but poorly constrained by observations. These effects are an important aspect of the response of Mars to space weather events and may also influence the escape of volatiles from Mars, particularly in the solar system's early history. Here we report the effects of the X8.2 flare on 10 September 2017 on the density and composition of the thermosphere of Mars. This analysis uses neutral number densities of He, O, N 2 , CO, Ar, and CO 2 from the MAVEN Neutral Gas and Ion Mass Spectrometer (NGIMS). From these observations, we investigate how the enhanced solar irradiance during the flare produced changes in the neutral upper atmosphere of Mars due to atmospheric heating and photochemistry. Flare-produced photochemical changes in the neutral thermosphere of Mars have been previously implied but not quantified. We find that at fixed altitudes, the number densities of all species barring He increase and the O/CO 2 ratio decreases by ∼15-45%, indicating thermal expansion. However, when viewed at fixed total number densities, the densities of CO 2 and Ar decrease, and the O/CO 2 ratio increases by up to a factor of ∼3. The photodissociation of CO 2 is one photochemical process that produces changes resembling those identified. The quantified changes will help to constrain the shifting chemical makeup of the upper atmosphere due to these impactful flare events and may aid modeling of flare behavior and the impact of flares on the evolution of the Martian climate.

show abstract

Section: Solar Storms Of September 2017 and Their Effects At Earth Anmentioning

confidence: 99%

Effects of the 10 September 2017 Solar Flare on the Density and Composition of the Thermosphere of Mars

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The first beginning late on 5 September was accompanied by arrival of a CME shock and ensuing geomagnetic storm with minimum Dst = −124 nT on 8 September. The second and stronger SEP event which produced a Ground Level Event signature without a geomagnetic storm was observed beginning on 10 September (O'Brien et al, ). Proton measurements by interplanetary Advanced Composition Explorer (c), low‐altitude Polar Orbiting Environmental Satellite (d), and Geostationary Operational Environmental Satellite‐15 (e) along with geosynchronous X‐ray measurements (a) and the Dst index (b) are shown in Figure .…”

Section: Observations Of Solar Proton Eventsmentioning

confidence: 99%

“…There was no accompanying geomagnetic storm, unlike the SEP event which accompanied the 6–8 September CME shock‐driven geomagnetic storm. The penetration of >60‐MeV protons into the magnetosphere during the 10–12 September 2017 solar energetic particle event was explored with the Relativistic Proton Spectrometer (Mazur et al, ) onboard Van Allen Probes (O'Brien et al, ). Lower‐energy solar protons with higher intensity can also cause serious space weather hazards and are thus deserving further attention.…”

Section: Introductionmentioning

confidence: 99%

Investigation of Solar Proton Access Into the Inner Magnetosphere on 11 September 2017

et al. 2019

View full text Add to dashboard Cite

In this study, access of solar energetic protons to the inner magnetosphere on 11 September 2017 is investigated by computing the reverse particle trajectories with the Dartmouth geomagnetic cutoff code (Kress et al., 2010). The maximum and minimum cutoff rigidity at each point along the orbit of Van Allen Probe A is numerically computed by extending the code to calculate cutoff rigidity for particles coming from arbitrary direction. Pulse height analyzed (PHA) data have the advantage of providing individual particle energies and effectively excluding background high‐energy proton contamination. This technique is adopted to study the cutoff locations for solar protons with different energy. The results demonstrate that cutoff latitude is lower for solar protons with higher energy, consistent with low‐altitude vertical cutoffs. Both the observations and numerical results show that proton access into the inner magnetosphere depends strongly on angle between particle arrival direction and magnetic west. The numerical result is approximately consistent with the observation that the energy of almost all solar protons stays above the minimum cutoff rigidity.

show abstract

“…More information on the proton belt can be found in, for example, Spjeldvik (), Beutier et al (), Albert et al (), Looper et al (), Selesnick, Looper, and Mewaldt (), Ginet et al (), Selesnick, Hudson, and Kress (), Selesnick et al (, , ), Mazur et al (, ), Tu, Cowee, and Liu (), and Borovsky et al (). In addition, we do not discuss any kind of trapped particles that originate from the nuclear reaction of ultrahigh energy proton (e.g., Gusev, Kohno et al, ; Gusev, Martin et al, ; Pugacheva et al, ; Selesnick, Looper, Mewaldt, & Labrador, ), suprathermal ionospheric heavy ions (e.g., Spjeldvik, ) such as iron ions (Christon et al, ; Spjeldvik et al, ) or carbon ions (Spjeldvik, ), high‐energy solar protons (e.g., O'Brien et al, ), or cosmic rays (e.g., Amato & Blasi, ; Blake et al, ; Smart et al, ; Shea et al, ; Smart & Shea, ).…”

Section: Introductionmentioning

confidence: 99%

Particle Dynamics in the Earth's Radiation Belts: Review of Current Research and Open Questions

et al. 2020

View full text Add to dashboard Cite

The past decade transformed our observational understanding of energetic particle processes in near‐Earth space. An unprecedented suite of observational systems was in operation including the Van Allen Probes, Arase, Magnetospheric Multiscale, Time History of Events and Macroscale Interactions during Substorms, Cluster, GPS, GOES, and Los Alamos National Laboratory‐GEO magnetospheric missions. They were supported by conjugate low‐altitude measurements on spacecraft, balloons, and ground‐based arrays. Together, these significantly improved our ability to determine and quantify the mechanisms that control the buildup and subsequent variability of energetic particle intensities in the inner magnetosphere. The high‐quality data from National Aeronautics and Space Administration's Van Allen Probes are the most comprehensive in situ measurements ever taken in the near‐Earth space radiation environment. These observations, coupled with recent advances in radiation belt theory and modeling, including dramatic increases in computational power, have ushered in a new era, perhaps a “golden era,” in radiation belt research. We have edited a Journal of Geophysical Research: Space Science Special Collection dedicated to Particle Dynamics in the Earth's Radiation Belts in which we gather the most recent scientific findings and understanding of this important region of geospace. This collection includes the results presented at the American Geophysical Union Chapman International Conference in Cascais, Portugal (March 2018) and many other recent and relevant contributions. The present article introduces and review the context, current research, and main questions that motivate modern radiation belt research divided into the following topics: (1) particle acceleration and transport, (2) particle loss, (3) the role of nonlinear processes, (4) new radiation belt modeling capabilities and the quantification of model uncertainties, and (5) laboratory plasma experiments.

show abstract

Solar Energetic Proton Access to the Magnetosphere During the 10–14 September 2017 Particle Event

Cited by 22 publications

References 45 publications

Effects of the 10 September 2017 Solar Flare on the Density and Composition of the Thermosphere of Mars

Effects of the 10 September 2017 Solar Flare on the Density and Composition of the Thermosphere of Mars

Investigation of Solar Proton Access Into the Inner Magnetosphere on 11 September 2017

Particle Dynamics in the Earth's Radiation Belts: Review of Current Research and Open Questions

Contact Info

Product

Resources

About