Optical Emission Spectroscopy

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Spectral Simulation Tools[edit]

PGOPHER

OPEN SOURCE. Windows, Mac, Linux. Fitting of rotational, vibrational, and electronic spectra. VERY PROMISING!

Lifbase

Closed source. No cost. Extremely limited library of molecules.

SpecAir

Closed source. 1000€/year license for academics. Not scriptable.

Diatomic

Closed source. No-cost unlock key. Not scriptable.

SpectralCalc

Closed source. "Emission/radiance plots are only available to users with an active subscription." ($49/month)

Simul

Created as part of a PhD thesis by Hana Šormová, 2005. I can't find a working download link.

Data Sources[edit]

Is there a good database for molecular optical emission lines?

NIST Diatomic Spectral Database

Papers[edit]

Whitepaper: Optical emission spectroscopy of plasma

Simulation of emission molecular spectra by a semi-automatic programme package: the case of C2 and CN diatomic molecules emitting during laser ablation of a graphite target in nitrogen environment (2004)

Simulation of the absorption and emission spectra of the SiCCl radical (2015)

Simulation of emission spectra from nonuniform reactive laser-induced plasmas (2015)

Optical emission studies of nitrogen plasma generated by IR CO2 laser pulses (2007)

Temperatures were estimated from the slope of the for a linear Boltzmann plot, ln(I(k)λ(k)/g(k)A(k)) vs E(k)/k(B), where "the values λ(k), g(k), A(k), and E(k) for selected atomic lines were obtained from the NIST Atomic Spectral Database":

  • I(k) is the emissivity in W/m³

"The emissivity of the ion lines is produced, on the average, near the inner region with higher temperature. On the contrary, the emissivity of the neutral atom lines comes, on average, from the low-temperature region close to the plasma front, where the neutral atom density is higher. The intensity measurements correspond to the integration of the local emissivity values along the line-of-sight, integrated in turn in the perpendicular directions. As a consequence, the neutral atom Boltzmann plot provides a temperature value which is a certain average of the low-temperature values in the plasma (7900 K), whereas the temperature obtained from the ion Boltzmann plot (21 000 K) averages the values existing in the high-temperature region."

Boltzmann Plots[edit]

Never Trust Boltzmann Plots, written by another plasma experimentalist working on helium plasmas. It references a paper, "THE EXCITATION TEMPERATURE IN (HELIUM) PLASMAS".

DISCUSSION ON EMISSION SPECTROSCOPY MEASUREMENTS FROM A DENSE ELECTROTHERMAL LAUNCHER PLASMA. This group is using optical emission lines and Boltzmann plots to estimate the temperatures of hot copper plasmas.

Determination of plasma temperature by a semi-empirical method. Another paper estimate the temperature of hot (5700K) copper plasma.