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Atomic, Molecular and Optical Physics

Series

2019

Spectroscopy

Articles 1 - 2 of 2

Full-Text Articles in Physics

The Population Densities Of Argon Metastable Levels, Nada Khogeer, Chelsy Gonzalez, Milka Nikolic Apr 2019

The Population Densities Of Argon Metastable Levels, Nada Khogeer, Chelsy Gonzalez, Milka Nikolic

Physics and Astronomy

In this experiment, we used the optical emission spectroscopy (OES) method to obtain the main properties of low temperature Argon plasma. The experiment was sustained in powers and pressures that ranges from 30-100 W and 15-100 mTorr. We used numerical methods for the Argon kinetic model to calculate metastable levels and resonant states for the first excited states in low temperature Argon plasma. By finding the ratio of two spectral lines and finding another ratio from a different upper energy level that goes down to the same two lower energy levels, we can construct a system of two nonlinear equations. …


Argon Metastable And Resonant Level Densities In Ar And Ar/Cl² Discharges Used For The Processing Of Bulk Niobium, Jeremy Peshl, Roderick Mcneill, Charles I. Sukenik, Milka Nikolić, Svetozar Popović, Leposava Vŭsković Jan 2019

Argon Metastable And Resonant Level Densities In Ar And Ar/Cl² Discharges Used For The Processing Of Bulk Niobium, Jeremy Peshl, Roderick Mcneill, Charles I. Sukenik, Milka Nikolić, Svetozar Popović, Leposava Vŭsković

Physics Faculty Publications

A comparative analysis of two popular spectroscopy techniques is conducted in a coaxial cylindrical capacitively coupled discharge designed for the plasma processing of superconducting radio frequency (SRF) cavities. The density of the metastable and resonant levels in Ar is measured in both Ar and Ar/Cl2 discharges to properly characterize the unique discharge system and aid in the development of a cavity etching routine. The first method, deemed the “branching fraction method,” utilizes the sensitivity of photon reabsorption of radiative decay to measure the lower state (metastable and resonant) densities by taking ratios of spectral lines with a common upper …