arXiv subjects

Edward L. Ruden

Publications and source records attributed to Edward L. Ruden.

2 recordsLinked to original sources

arXiv2026

Ionization rate vs. laser intensity determined from ion count vs. peak intensity due to neutral gas exposure to an 800 nm ultrashort pulsed laser

The optical cycle-averaged ionization rate of Ar, O$_2$, and N$_2$ vs. local instantaneous laser intensity $I$ for linear polarized 800 nm light is determined up to approx. 300 TW/cm$^2$ by numerically inverting published time-of-flight ion spectrometer data. The published Ar$^+$ collection efficiency of the microchannel plate (MCP) at the end of the spectrometer and its $I_0$ scale are recalibrated by fitting it to its high $I_0$ solution. The relative collection efficiencies of the other species are determined by published MCP cathode data. Results for O$_2$ are consistent with a reevaluation of published data used to determine its cross section $σ_8$ in the multiphoton (low $I$) regime.

physics.atom-ph↗

arXiv2026

Temperature and mean axial momentum vs. laser intensity of electrons released from O$_2$ by an 800 nm ultrashort pulsed laser

A semi-empirical model is presented for the thermalized temperature $T$ and mean momentum in the direction of laser propagation <$p_{fz}$> of electrons released from O$_2$ after the passage of a focused 800 nm ultrashort pulsed laser pulse vs. peak laser intensity $I_0$ to provide initial conditions for plasma electrodynamic simulations. For this, theoretical kinetic energy spectra based on the most probable ionization path of a nonadiabatic Strong Field Approximation (SFA) are fit to experimental spectra by two adjustable parameters assumed to represent the effects of electron recombination with or rescatter off of its parent ion during the optical cycle subsequent to ionization. These are effects not treated by the original SFA. The classical kinematics of elastic rescatter and the Lorentz force, then, are used to estimate <$p_{fz}$>.

physics.plasm-ph↗