Journal ArticleDOI
Observations of Solar Energetic Particles from ^3He-rich Events over a Wide Range of Heliographic Longitude
Mark E. Wiedenbeck,G. M. Mason,Christina Cohen,Nariaki Nitta,Raúl Gómez-Herrero,Raúl Gómez-Herrero,Dennis Haggerty +6 more
TLDR
In this paper, the authors present the observations of the ^3He-rich event of 2010 February 7, which was detected at all three spacecraft when they spanned 136° in heliographic longitude.Abstract:
A prevailing model for the origin of ^3He-rich solar energetic particle (SEP) events attributes particle acceleration to processes associated with the reconnection between closed magnetic field lines in an active region and neighboring open field lines. The open field from the small reconnection volume then provides a path along which accelerated particles escape into a relatively narrow range of angles in the heliosphere. The narrow width (standard deviation 60°. We present the observations of the ^3He-rich event of 2010 February 7, which was detected at all three spacecraft when they spanned 136° in heliographic longitude. Measured fluences of ^3He in this event were found to have a strong dependence on longitude which is well fit by a Gaussian with standard deviation ~48° centered at the longitude that is connected to the source region by a nominal Parker spiral magnetic field. We discuss several mechanisms for distributing flare-accelerated particles over a wide range of heliographic longitudes including interplanetary diffusion perpendicular to the magnetic field, spreading of a compact cluster of open field lines between the active region and the source surface where the field becomes radial and opens out into the heliosphere, and distortion of the interplanetary field by a preceding coronal mass ejection. Statistical studies of additional ^3He-rich events detected at multiple spacecraft will be needed to establish the relative importance of the various mechanisms.read more
Citations
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Journal ArticleDOI
The Solar Probe Plus Mission: Humanity’s First Visit to Our Star
N. J. Fox,Marco Velli,Stuart D. Bale,R. B. Decker,Andrew Driesman,Russell A. Howard,Justin C. Kasper,Justin C. Kasper,James Kinnison,M. Kusterer,David Lario,Mary Kae Lockwood,David J. McComas,David J. McComas,N.-E. Raouafi,Adam Szabo +15 more
TL;DR: The first spacecraft to fly into the low solar corona is the Solar Probe Plus (SPP) as discussed by the authors, which is scheduled for launch in mid-2018 and will perform 24 orbits over a 7-year nominal mission duration.
Journal ArticleDOI
Large gradual solar energetic particle events
M. I. Desai,Joe Giacalone +1 more
TL;DR: This paper provides a comprehensive review of the current state of knowledge of these important phenomena, and summarizes some of the key questions that will be addressed by two upcoming missions—NASA's Solar Probe Plus and ESA's Solar Orbiter.
Journal ArticleDOI
> 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
Ian G. Richardson,Ian G. Richardson,T. T. von Rosenvinge,Hilary V. Cane,E. R. Christian,Christina Cohen,A. W. Labrador,R. A. Leske,R. A. Mewaldt,Mark E. Wiedenbeck,E. C. Stone +10 more
TL;DR: In this paper, the authors summarize the properties of more than 200 individual > 25 MeV solar proton events, some detected by multiple spacecraft, and provide a catalog of these events and their solar sources and associations.
Journal ArticleDOI
Large-scale Globally Propagating Coronal Waves
TL;DR: This review focuses on demonstrating how the numerous observational findings of the last one and a half decades can be used to constrain the authors' models of large-scale coronal waves, and how a coherent physical understanding of these disturbances is finally emerging.
Journal ArticleDOI
Statistical survey of widely spread out solar electron events observed with STEREO and ACE with special attention to anisotropies
Nina Dresing,Raúl Gómez-Herrero,Bernd Heber,Andreas Klassen,Olga Malandraki,W. Dröge,Yulia Kartavykh +6 more
TL;DR: In this paper, an ensemble of SEP events were observed between 2009 and mid-2013 by at least two spacecrafts and show a remarkably wide particle spread in longitude (wide-spread events).
References
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Interplanetary Magnetic Field Line Mixing Deduced from Impulsive Solar Flare Particles
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Physical Parameters of Solar X-Ray Jets
Masumi Shimojo,Kazunari Shibata +1 more
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