Substorm onsets observed by CRRES: Determination of energetic particle source regions

1996 ◽  
Vol 101 (A6) ◽  
pp. 13137-13154 ◽  
Author(s):  
R. H. W. Friedel ◽  
A. Korth ◽  
G. Kremser
Keyword(s):  
Energetic Particle ◽  
Particle Source ◽  
Source Regions ◽  
Substorm Onsets

scholarly journals Long-lived energetic particle source regions on the Sun

2015 ◽  
Vol 642 ◽  
pp. 012002 ◽  
Author(s):  
R Bučík ◽  
D E Innes ◽  
N H Chen ◽  
G M Mason ◽  
R Gómez-Herrero ◽  
...  
Keyword(s):  
Energetic Particle ◽  
The Sun ◽  
Particle Source ◽  
Source Regions

Ultraviolet spectroscopy of solar energetic particle source regions

2005 ◽  
Author(s):  
J. L. Kohl ◽  
S. Cranmer ◽  
R. Esser ◽  
L. D. Gardner ◽  
S. Fineschi ◽  
...  
Keyword(s):  
Energetic Particle ◽  
Solar Energetic Particle ◽  
Ultraviolet Spectroscopy ◽  
Particle Source ◽  
Source Regions

scholarly journals Variable Ion Compositions of Solar Energetic Particle Events in the Inner Heliosphere: A Field Line Braiding Model with Compound Injections

2022 ◽  
Vol 924 (1) ◽  
pp. 22
Author(s):  
Fan Guo ◽  
Lulu Zhao ◽  
Christina M. S. Cohen ◽  
Joe Giacalone ◽  
R. A. Leske ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Energetic Particle ◽  
Radial Distance ◽  
Solar Energetic Particle ◽  
The Sun ◽  
Ion Composition ◽  
Source Regions ◽  
Solar Energetic Particle Events ◽  
Composition Ratios ◽  
Inner Heliosphere

Abstract We propose a model for interpreting highly variable ion composition ratios in solar energetic particle (SEP) events recently observed by the Parker Solar Probe (PSP) at 0.3–0.45 au. We use numerical simulations to calculate SEP propagation in a turbulent interplanetary magnetic field with a Kolmogorov power spectrum from large scales down to the gyration scale of energetic particles. We show that when the source regions of different species are offset by a distance comparable to the size of the source regions, the observed energetic particle composition He/H can be strongly variable over more than two orders of magnitude, even if the source ratio is at the nominal value. Assuming a 3He/4He source ratio of 10% in impulsive 3He-rich events and the same spatial offset of the source regions, the 3He/4He ratio at observation sites also vary considerably. The variability of the ion composition ratios depends on the radial distance, which can be tested by observations made at different radial locations. We discuss the implications of these results on the variability of ion composition of impulsive events and on further PSP and Solar Orbiter observations close to the Sun.

scholarly journals Distinguishing volcanic from impact glasses—The case of the Cali glass (Colombia)

Geology ◽  
2021 ◽  
Author(s):  
Ludovic Ferrière ◽  
Alvaro P. Crósta ◽  
Wencke Wegner ◽  
Eugen Libowitzky ◽  
Fabio Iwashita ◽  
...  
Keyword(s):  
Volcanic Glass ◽  
Ionization Mass ◽  
Volcanic Origin ◽  
Source Regions ◽  
Natural Glass ◽  
Different Types ◽  
Multimethod Approach ◽  
Extended Area ◽  
Impact Origin

Natural glass occurs on Earth in different geological contexts, mainly as volcanic glass, fulgurites, and impact glass. All these different types of glasses are predominantly composed of silica with variable amounts of impurities, especially the alkalis, and differ in their water content due to their mode of formation. Distinguishing between different types of glasses, on Earth and also on the Moon and on other planetary bodies, can be challenging. This is particularly true for glasses of impact and volcanic origin. Because glass is often used for the determination of the age of geological events, even if out of geological context, as well as to derive pressure and temperature constraints, or to evaluate the volatile contents of magmas and their source regions, we rely on methods that can unambiguously distinguish between the different types of glasses. We used the case of the Cali glass, found in an extended area close to the city of Cali in western Colombia, which was previously suggested to be of impact or volcanic origin, to show that, using a multimethod approach (i.e., combining macroscopic observations, chemical and isotopic data, and H2O content), it is possible to distinguish between different formation modes. A suite of Cali glass samples was analyzed using electron microprobe, instrumental neutron activation analysis, thermal ionization mass spectrometry, and Fourier-transform infrared spectroscopy, allowing us to definitively exclude an impact origin and instead classify these glasses as a rhyolitic volcanic glass (obsidian). Our results suggest that other “unusual glass occurrences” that are claimed, but not convincingly proven, to be of impact origin should be reexamined using the same methodology as that applied here.

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