&gt; 25 MeV Proton Events Observed by the High Energy Telescopes on the STEREO A and B Spacecraft and/or at Earth During the First ∼ Seven Years of the STEREO Mission

Richardson, I. G.; Rosenvinge, T. T. von; Cane, H. V.; Christian, E. R.; Cohen, C. M. S.; Labrador, A. W.; Leske, R. A.; Mewaldt, R. A.; Wiedenbeck, M. E.; Stone, E. C.

doi:10.1007/s11207-014-0524-8

Cited by 236 publications

(362 citation statements)

References 65 publications

Supporting

Mentioning

324

Contrasting

Unclassified

Order By: Relevance

“…Interactions between CMEs from the same AR have often been discussed (e.g., Lugaz et al 2005bLugaz et al , 2007Lugaz et al , 2013Xiong et al 2006), but CMEs can be spatially extended and those from distant regions may also interact, adding complexity to solar wind data (e.g., Temmer et al 2012). It is also possible that sympathetic events may play a role in SEP events observed at widely separate locations (e.g., Richardson et al 2014;Gómez-Herrero et al 2015).…”

Section: Introductionmentioning

confidence: 99%

A Numerical Study of Long-Range Magnetic Impacts During Coronal Mass Ejections

Jin

Schrijver

Cheung

et al. 2016

ApJ

View full text Add to dashboard Cite

With the global view and high-cadence observations from Solar Dynamics Observatory/Atmospheric Imaging Assembly and Solar TErrestrial RElations Observatory, many spatially separated solar eruptive events appear to be coupled. However, the mechanisms for "sympathetic" events are still largely unknown. In this study, we investigate the impact of an erupting flux rope on surrounding solar structures through large-scale magnetic coupling. We build a realistic environment of the solar corona on 2011 February 15 using a global magnetohydrodynamics model and initiate coronal mass ejections (CMEs) in active region 11158 by inserting Gibson-Low analytical flux ropes. We show that a CME's impact on the surrounding structures depends not only on the magnetic strength of these structures and their distance to the source region, but also on the interaction between the CME and the large-scale magnetic field. Within the CME expansion domain where the flux rope field directly interacts with the solar structures, expansion-induced reconnection often modifies the overlying field, thereby increasing the decay index. This effect may provide a primary coupling mechanism underlying the sympathetic eruptions. The magnitude of the impact is found to depend on the orientation of the erupting flux rope, with the largest impacts occurring when the flux rope is favorably oriented for reconnecting with the surrounding regions. Outside the CME expansion domain, the influence of the CME is mainly through field line compression or post-eruption relaxation. Based on our numerical experiments, we discuss a way to quantify the eruption impact, which could be useful for forecasting purposes.

show abstract

Section: Introductionmentioning

confidence: 99%

A Numerical Study of Long-Range Magnetic Impacts During Coronal Mass Ejections

Jin

Schrijver

Cheung

et al. 2016

ApJ

View full text Add to dashboard Cite

show abstract

“…For Solar Cycle 24, we use an updated version (Richardson et al, 2016) of the catalog of 25 MeV proton events compiled by Richardson et al (2014) using observations from the High Energy Telescopes (von Rosenvinge et al, 2008) on the STEREO A ("Ahead") and B ("Behind") spacecraft (Kaiser et al, 2008) and from near-Earth spacecraft, since launch of the STEREO spacecraft on October 26, 2006. STEREO A and B moved ahead or behind the Earth in its orbit, respectively, advancing at ∼ 22 • /year, and passed each other on the far side of the Sun in March 2015.…”

Section: Solar Cycles 23 and 24mentioning

confidence: 99%

“…For direct comparison with the events observed by near-Earth spacecraft in Cycle 23 (Cane et al, 2010), we will generally focus here on the Cycle 24 events that were observed near the Earth. Figure 2 is an updated version of Figure 10 of Richardson et al (2014) which shows in the top panel the peak 25 MeV proton intensities for events observed at Earth in 1996-2015. The second panel shows the number of 25 MeV proton events/Carrington rotation and the three-rotation running averages.…”

Section: Solar Cycles 23 and 24mentioning

confidence: 99%

“…These include: Cane et al (1988), where observations from 235 events in 1967-1985 were used to demonstrate clearly the contribution of interplanetary shocks to the distribution of SEPs in longitude; Cane et al (2010), which discussed 280 events in 1997-2006and Richardson et al (2014), which summarized the properties of 209 25 MeV proton events observed by the STEREO A or B spacecraft and/or near the Earth in 2006-2013. Such events are also generally associated with relatively energetic solar events. For example (Cane et al (2010); Richardson et al (2014)), essentially all 25 MeV proton events are accompanied by CMEs, X-ray flares (if originating on the front side of the Sun), type III radio emissions, and less frequently, by type II radio bursts (e.g., 53% of the events of Richardson et al (2014) were accompanied by type II bursts identified in WIND/WAVES and/or STEREO/SWAVES observations (http://www-lep.gsfc.nasa.gov/waves/)).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

25 MeV solar proton events in Cycle 24 and previous cycles

Richardson

Rosenvinge

Cane

2017

Advances in Space Research

View full text Add to dashboard Cite

We summarize observations of around a thousand solar energetic particle (SEP) events since 1967 that include ∼ 25 MeV protons, made by various near-Earth spacecraft (IMPs 4, 5, 7, 8, ISEE 3, SOHO), that encompass Solar Cycle 20 to the current cycle (24). We also discuss recent observations of similar SEP events in Cycle 24 made by the STEREO spacecraft. The observations show, for example, that the time distribution of ∼ 25 MeV proton events varies from cycle to cycle. In particular, the time evolution of the SEP occurrence rate in Cycle 24 is strongly asymmetric between the northern and southern solar hemispheres, and tracks the sunspot number in each hemisphere, whereas Cycle 23 was more symmetric. There was also an absence of 25 MeV proton events during the solar minimum preceding Cycle 24 (other minima show occasional, often reasonably intense events). So far, events comparable to the exceptionally intense events detected in Cycles 22 and 23 have not been observed at Earth in Cycle 24, though Cycle 21 (the largest of the cycles considered here) also apparently lacked such events. We note a correlation between the rates of intense 25 MeV proton events and "ground level enhancements" (GLEs) observed by neutron monitors, since 1967, and conclude that the number of "official" GLEs (1) observed to date in Cycle 24 appears to be significantly lower than expected (5 to 7 ± 1) based on the rate of intense 25 MeV proton events in this cycle.

show abstract

“…Laitinen et al (2016) showed that the wide SEP events observed with multiple spacecraft at different heliographic longitudes at 1 AU (e.g. Lario et al 2013;Dresing et al 2012;Wiedenbeck et al 2013;Dresing et al 2014;Cohen et al 2014;Richardson et al 2014) could be explained using this approach with particle transport parameters consistent with the interplanetary turbulence properties already with a narrow source at the Sun.…”

Section: Introductionmentioning

confidence: 99%

Early propagation of energetic particles across the mean field in turbulent plasmas

Laitinen

Dalla

Marriott

2017

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Propagation of energetic particles across the mean field direction in turbulent magnetic fields is often described as spatial diffusion. Recently, it has been suggested that initially the particles propagate systematically along meandering field lines, and only later reach the time-asymptotic diffusive cross-field propagation. In this paper, we analyse cross-field propagation of 1-100 MeV protons in composite 2D-slab turbulence superposed on a constant background magnetic field, using full-orbit particle simulations, to study the non-diffusive phase of particle propagation with a wide range of turbulence parameters. We show that the early-time non-diffusive propagation of the particles is consistent with particle propagation along turbulently meandering field lines. This results in a wide cross-field extent of the particles already at the initial arrival of particles to a given distance along the mean field direction, unlike when using spatial diffusion particle transport models. The cross-field extent of the particle distribution remains constant for up to tens of hours in turbulence environment consistent with the inner heliosphere during solar energetic particle events. Subsequently, the particles escape from their initial meandering field lines, and the particle propagation across the mean field reaches time-asymptotic diffusion. Our analysis shows that in order to understand solar energetic particle event origins, particle transport modelling must include non-diffusive particle propagation along meandering field lines.

show abstract

> 25 MeV Proton Events Observed by the High Energy Telescopes on the STEREO A and B Spacecraft and/or at Earth During the First ∼ Seven Years of the STEREO Mission

Cited by 236 publications

References 65 publications

A Numerical Study of Long-Range Magnetic Impacts During Coronal Mass Ejections

A Numerical Study of Long-Range Magnetic Impacts During Coronal Mass Ejections

25 MeV solar proton events in Cycle 24 and previous cycles

Early propagation of energetic particles across the mean field in turbulent plasmas

Contact Info

Product

Resources

About