What's the excitation temp of He? How to get this?(DBD plasma)

In summary, the conversation discusses an experiment using He-1 to create plasma at room temperature, with a focus on measuring the plasma emission energy using high intensity wavelengths. The formula ln(a) is used to calculate the excitation temperature, with a paper being referenced to select the appropriate wavelengths. The resulting calculation for T-ex is over 1000K, and the discussion touches on the concept of non-equilibrium plasma and the role of hot electrons in creating radiation in the DBD.
  • #1
Lh0907
7
0
Hello.

I've experiment, which makes plasma using He-1 under atmoshpere & room temp,it's to show how DBD plasma emission energy.

As I know that high intensity wave length of He-1 are 588nm,668nm,708nm..etc.

If take a formula, ln(a) is propotional to -1/(T-ex). ln(a) is some value.(a has wave length,intensity..etc).

To calculate excitation temp, I read a paper which pick up non-degeneracy wave length(to claer select high intensity wave length).

I've got a calculation T-ex, which is over 1000K.(Energy level 1s 1s2p -1s3d)

Is the right? (As I know, energy gap is around 0.3~0.7eV. But Is it also maintain under
DBD plasma?
 
Physics news on Phys.org
  • #2
That is why it is called a non-equilibrium plasma. The gas in the DBD is in equilibrium and has a temperature of 300-400k but the electrons are not in equibrium. The electrons are heated by the electrical field and the DBD contains hot electrons that have energies of several eV. It is these electrons that create the radiation by impact on He
 

What is the excitation temperature of He?

The excitation temperature of He refers to the temperature at which the majority of the helium atoms in a plasma state are in an excited energy level. This temperature can vary depending on the type of plasma and the experimental conditions.

What is DBD plasma?

DBD (Dielectric Barrier Discharge) plasma is a type of non-thermal plasma that is created by applying a high voltage to a gas trapped between two dielectric barriers. This results in a plasma that is localized and has a relatively low gas temperature compared to other types of plasmas.

What factors affect the excitation temperature of He in DBD plasma?

The excitation temperature of He in DBD plasma can be affected by various factors, including the gas composition, gas pressure, applied voltage, and electrode geometry. These factors can influence the energy of the electrons in the plasma, which in turn affects the excitation temperature of the helium atoms.

How is the excitation temperature of He in DBD plasma measured?

The excitation temperature of He in DBD plasma is typically measured using spectroscopic techniques. This involves analyzing the spectral lines emitted by the excited helium atoms and using the Boltzmann plot method to determine the temperature at which the majority of the atoms are in an excited state.

How can the excitation temperature of He in DBD plasma be controlled?

The excitation temperature of He in DBD plasma can be controlled by adjusting the experimental parameters, such as the gas composition, gas pressure, and applied voltage. Additionally, using different electrode geometries or adding catalysts to the plasma can also affect the excitation temperature of helium atoms.

Back
Top