In the context of plasma physics, the terms "isothermally confined electrons" and "adiabatically expanding electrons" refers to different scenarios that describe the behavior of electrons within a plasma. Breaking down these terms:

1. Isothermally Confined Electrons:

- Isothermal confinement refers to a situation where a group of particles (in this case, electrons) are held at a constant temperature. This means that the energy of the particles remains the same, and any changes in pressure or volume are balanced in a way that the temperature remains constant.

- In a plasma, isothermal confinement of electrons might occur in situations where the plasma is confined by some external mechanism, such as a magnetic field or a physical boundary, in a way that prevents significant expansion or compression. The electrons' energy remains constant, and any changes in their behavior are primarily due to the influence of the external confinement, not changes in their internal energy.

2. Adiabatically Expanding Electrons:

- Adiabatic expansion refers to a process where a group of particles expand in a way that there is no exchange of heat with the surroundings. In other words, the energy of the particles remains constant, and any changes in their behavior are due to changes in volume and pressure.

- In the context of a plasma, adiabatic expansion of electrons might occur when the plasma expands rapidly and the electrons move to regions of lower pressure. As they expand, they do work against the external pressure, and this can lead to cooling due to the decrease in temperature.

- This cooling effect during adiabatic expansion is similar to what happens when air rapidly expands as it rises in the Earth's atmosphere, leading to a drop in temperature (adiabatic cooling).

To summarize:

- Isothermally Confined Electrons: Electrons are held at a constant temperature, and any changes in their behavior are influenced by external confinement mechanisms. Their energy remains constant, and changes in pressure and volume do not significantly affect their temperature.

- Adiabatically Expanding Electrons: Electrons expand rapidly without exchanging heat with the surroundings, resulting in a decrease in temperature due to the work done against external pressure.

Both of these scenarios are relevant in understanding the behavior of electrons within a plasma, where interactions between particles can be complex due to the presence of electromagnetic fields and other factors. The terms help describe how the energy and temperature of electrons change as the plasma undergoes different processes or conditions.

Yetoka Swu Thank you so much for the clarification. As mentioned by you in the last paragraph, can you suggest some papers/works where both the scenarios are addressed explicitly.

Ayesha Nanda

https://inis.iaea.org/search/search.aspx?orig_q=RN:51116574

https://inis.iaea.org/search/search.aspx?orig_q=RN:52034893

DOI 10.1088/1367-2630/aac877