Variations of Protons and Doubly Ionized Helium Ions in the Solar Wind

Abstract. Variations of parameters of twice-ionized helium ions – He++ ions or α-particles – in the solar wind plasma during the interplanetary shock front passage are investigated. We used the data measured by the BMSW (Bright Monitor of Solar Wind) instrument installed on the SPEKTR-R satellite, which operated since August 2011 to 2019 and registered 57 interplanetary shocks. According to received data, the parameters of He++ ions were calculated: velocity Vα, temperature Tα, absolute density Nα and relative density (helium abundance) Nα/Np. The correlation of changes in helium abundance Nα/Np with the parameters βi, θBn and MMS were investigated.

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Newly Formed Energy Dispersion Signatures of Low-energy Proton, Oxygen and Helium Ions in the Inner Magnetosphere

10.5194/egusphere-egu2020-4520 ◽

2020 ◽

Author(s):

Jie Ren ◽

Qiugang Zong ◽

Chao Yue ◽

Xuzhi Zhou

Keyword(s):

Solar Wind ◽

Electric Fields ◽

Wind Pressure ◽

Helium Ions ◽

Energy Dispersion ◽

Oxygen Ion ◽

Ae Index ◽

Solar Wind Pressure ◽

The Relationship ◽

Ion Species

Here we report the observations of the simultaneously formed energy dispersion structures of proton, oxygen and helium ions in the inner magnetospehre using Van Allen Probes data. The energy of the ourter edge of this sturcture is only several eV, and the energy of this structure is increasing with the decreasing L shell, which can be up to several keV especially for oxygen ions. The energy dispersion structure has a larger upper energy limit for the particle species with largher mass. But the upper velocity limits for different ion species are almost the same, which indicates that these different ions are accelerated by electric fields via the ExB drift. A statistical study with four years data shows that 1. This kind of structure is mainly distributed in the duskside and nighside; 2. The upper velocity for the oxygen ion exhibits a linear relation with both proton and helium ions; 3. The relationship between the occurrence rates and different parameters such as solar wind velocity, solar wind pressure, SYMH, Kp and AE index indicates that the formation of this structure is probably related to substorm activities.

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Helium abundance and speed difference between helium ions and protons in the solar wind from coronal holes, active regions, and quiet Sun

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty1211 ◽

2018 ◽

Vol 478 (2) ◽

pp. 1884-1892 ◽

Cited By ~ 6

Author(s):

Hui Fu ◽

Maria S Madjarska ◽

Bo Li ◽

Lidong Xia ◽

Zhenghua Huang

Keyword(s):

Solar Wind ◽

Coronal Holes ◽

Active Regions ◽

Helium Abundance ◽

Helium Ions ◽

Quiet Sun ◽

Speed Difference

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Saturn's E, G and F rings: modulated by the plasma sheet

International Astronomical Union Colloquium ◽

10.1017/s0252921100101666 ◽

1984 ◽

Vol 75 ◽

pp. 597

Author(s):

E. Grün ◽

G.E. Morfill ◽

T.V. Johnson ◽

G.H. Schwehm

Keyword(s):

Solar Wind ◽

Direct Contact ◽

Transport Processes ◽

Time Variable ◽

Dust Particles ◽

Spatial Diffusion ◽

Drag Forces ◽

Orbit Perturbation ◽

Time Variations ◽

F Ring

ABSTRACTSaturn's broad E ring, the narrow G ring and the structured and apparently time variable F ring(s), contain many micron and sub-micron sized particles, which make up the “visible” component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. It is suggested that the extent of the E ring and the braided, kinky structure of certain portions of the F rings as well as possible time variations are a result of plasma induced electromagnetic perturbations and drag forces. The G ring, in this scenario, requires some form of shepherding and should be akin to the F ring in structure. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 102to 104years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

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Quantitative surface damage studies by H.R.E.M.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015513x ◽

1989 ◽

Vol 47 ◽

pp. 632-633

Author(s):

S. R. Singh ◽

H. J. Fan ◽

L. D. Marks

Keyword(s):

Solar Wind ◽

Quantitative Analysis ◽

Surface Science ◽

Surface Damage ◽

Space Environment ◽

Oxygen Desorption ◽

The Past ◽

Diffusion Controlled ◽

Original Observation ◽

Substantial Interest

Since the original observation that the surfaces of materials undergo radiation damage in the electron microscope similar to that observed by more conventional surface science techniques there has been substantial interest in understanding these phenomena in more detail; for a review see. For instance, surface damage in a microscope mimics damage in the space environment due to the solar wind and electron beam lithographic operations.However, purely qualitative experiments that have been done in the past are inadequate. In addition, many experiments performed in conventional microscopes may be inaccurate. What is needed is careful quantitative analysis including comparisons of the behavior in UHV versus that in a conventional microscope. In this paper we will present results of quantitative analysis which clearly demonstrate that the phenomena of importance are diffusion controlled; more detailed presentations of the data have been published elsewhere.As an illustration of the results, Figure 1 shows a plot of the shrinkage of a single, roughly spherical particle of WO3 versus time (dose) driven by oxygen desorption from the surface.

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