Self-similar two-electron temperature plasma expansion into vacuum

Bennaceur-Doumaz, D.; Bara, Djemai; Djebli, M.

doi:10.1017/s0263034615000877

Cited by 17 publications

(7 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Debye length loses its importance as a characteristic length in the plasma(Bennaceur- Doumaz et al 2015), and we observe the plasma expansion in a frame moving with ionacoustic speed c s , making the evolution of this expansion with time less transparent. The shortcomings of this method have been clearly recognized, but it may offer a straightforward way to solve the complicated system of nine partial differential equations and create premises for future interpretations of the solutions.…”

mentioning

confidence: 85%

Ionospheric losses of Venus in the solar wind

Salem

Moslem

Lazar

et al. 2020

Advances in Space Research

View full text Add to dashboard Cite

The nature of ionospheric losses from Venus is of essential importance for understanding the ionosphere dynamics of this unmagnetized planet. A plausible mechanism that can explain the escape of charged particles involves the solar wind interaction with the upper atmospheric layers of Venus. The hydrodynamic approach proposed for plasma expansion in the present study comprises two populations of positive ions and the neutralizing electrons, which interact with the solar wind electrons and protons. The fluid equations describing the plasma are solved numerically using a self-similar approach. The behavior of plasma density, velocity, and electric potential, as well as their reliance upon solar wind parameters have been examined. It is found that for noon midnight sites, the oxygen ion-to-electron relative density may be the main factor to enhance the ionic loss. However, the other parameters, like hydrogen density and solar wind density and velocity seem to do not stimulate the runaway ions. For lower dawn-dusk region, the plasma are composed of hydrogen and oxygen ions as well as electrons, but for higher altitudes only hydrogen ions and electrons are encountered. All ionic densities play an important role either to reduce or boost the ionic loss. The streaming solar wind velocity has no effect on the plasma escaping for lower altitudes, but it reduces the expansion at higher altitudes.

show abstract

mentioning

confidence: 85%

Ionospheric losses of Venus in the solar wind

Salem

Moslem

Lazar

et al. 2020

Advances in Space Research

View full text Add to dashboard Cite

show abstract

“…When there are multiple electron populations present, the ambipolar driving of the ions is controlled by the temperature of the hotter population of electrons (cf. Diaw and Mora, 2013;Kiefer et al, 2013;Bennaceur-Doumaz et al, 2015). Ambipolar electric fields set up by a relativistic-electron population with 100-keV temperatures can result in proton acceleration to 1000's of km/s from the edge of a plasma (e.g.…”

Section: Needed Future Calculationsmentioning

confidence: 99%

Do Impulsive Solar-Energetic-Electron (SEE) Events Drive High-Voltage Charging Events on the Nightside of the Moon?

Borovsky

Delzanno

2021

Front. Astron. Space Sci.

View full text Add to dashboard Cite

When the Earth’s moon is in the supersonic solar wind, the darkside of the Moon and the lunar plasma wake can be very dangerous charging environments. In the absence of photoelectron emission (dark) and in the absence of cool plasma (wake), the emission or collection of charge to reduce electrical potentials is difficult. Unique extreme charging events may occur during impulsive solar-energetic-electron (SEE) events when the lunar wake is dominated by relativistic electrons, with the potential to charge and differentially charge objects on and above the lunar surface to very-high negative electrical potentials. In this report the geometry of the magnetic connections from the Sun to the lunar nightside are explored; these magnetic connections are the pathways for SEEs from the Sun. Rudimentary charging calculations for objects in the relativistic-electron environment of the lunar wake are performed. To enable these charging calculations, secondary-electron yields for impacts by relativistic electrons are derived. Needed lunar electrical-grounding precautions for SEE events are discussed. Calls are made 1) for future dynamic simulations of the plasma wake in the presence of time-varying SEE-event relativistic electrons and time-varying solar-wind magnetic-field orientations and 2) for future charging calculations in the relativistic-electron wake environment and on the darkside lunar surface.

show abstract

“…This approach is often used to understand various processes in space and laboratory plasmas, such as the expansion of astrophysical objects, laser-plasma interaction, and creation of surface nano-structures (see e.g. Mora 2003;Djebli 2003;Djebli et al 2004;Moslem 2012;El-Labany et al 2014;Bennaceur-Doumaz et al 2015;Elkamash & Kourakis 2016;Shahmansouri et al 2017;Moslem et al 2017). This approach requires a new variable ξ = x/c s t, which is used in Eqs.…”

Section: Model Equationsmentioning

confidence: 99%

Ion escape from the upper ionosphere of Titan triggered by the solar wind

Moslem

Salem

Sabry

et al. 2019

Astrophys Space Sci

View full text Add to dashboard Cite

The observed escape of ions from the ionosphere of Titan suggests a potential role of the solar wind in the interaction with the upper atmospheric layers. We investigate such a plausible scenario using a hydrodynamic fluid approach for the plasma expansion in the upper ionosphere of Titan, combining (Maxwellian) electrons and three different species of positive ions which interact with the solar wind electrons and protons. Using a self-similar transformation, numerical analysis is performed to solve the basic equations, and characterize the plasma density, velocity, and electric potential during the expansion. It is found that increasing the solar wind proton number density leads to a reduction the ion escape, while the effect of electrons is opposite stimulating the ion escape. Moreover, the expansion domain does not change for more energetic protons. The heavier ions has the leading role in controlling the ion escape, i.e. by comparison to CH + 5 ions, C 2 H + 5 ions appear to have a more influence in the loss from Titan ionosphere. For a higher temperature contrast between ions and electrons, the depletion rate of the density increases and the ions move faster, leading to a higher ionic loss.

show abstract

Self-similar two-electron temperature plasma expansion into vacuum

Cited by 17 publications

References 37 publications

Ionospheric losses of Venus in the solar wind

Ionospheric losses of Venus in the solar wind

Do Impulsive Solar-Energetic-Electron (SEE) Events Drive High-Voltage Charging Events on the Nightside of the Moon?

Ion escape from the upper ionosphere of Titan triggered by the solar wind

Contact Info

Product

Resources

About