Measuring laser effects on plasma measurements by estimating energy deposition in laser-produced plasmas*

Laser-plasma interactions pervade modern physics, from low-power table-top setups for plasma optics to high-power stadium-sized laser fusion experiments. The effect of optical diagnostics on plasma measurements is an often-overlooked regime of this parameter space. They are a cornerstone of experimental plasma physics, allowing the measurement of important basic plasma quantities such as electron and ion density/temperature, turbulent kinetic energy, and bulk velocity. However, certain laser-focusing diagnostics such as Thomson scattering have been observed to deposit non-trivial energy into plasmas.  In order to extract meaningful information from these measurements, it is essential to understand and mitigate direct laser effects.  More specifically, we seek to understand how energy is deposited during laser interactions with plasma. We study plasmas generated by ionizing air and estimate energy deposition through time resolved interferometry and spectroscopy. Additionally, we estimate the ionization state of the plasma through comparisons with simulation data.