A Solar Rayleigh scattering power per molecule and photoionization rates for CO2, H2O

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Summary
Imagine an isolated neutral molecule of CO2 or H2O, or an Argon atom 1AU from the Sun. Integrated over all wavelengths, what is the photoionization rate? What is the intercepted Raleigh scattering power per molecule?
I'm pondering the behavior and persistence of rocket exhaust plume molecules far above the atmosphere. For example, the plume from an apogee circularization thrust from GTO (Geosynchronous Transfer Orbit) to GEO (Geosynchronous orbit). CO₂ and H₂O are among the molecular species emitted by a hydrocarbon-fuel or hydrogen-fuel rocket engine. Argon propellant is favored for VASIMR and helicon thrusters. Very fast molecules might escape, very slow molecules might reenter, but for GTO to GEO thrust, many plume molecules will have retrograde velocities that put them in persistent elliptical (Kepler) orbits, intercepting the launch path they were emitted from once per Kepler orbit.

Rayleigh scattering will slowly diffuse the molecular Kepler orbits; photoionization will trap ionized molecules on magnetic field lines intercepting the radius at which they ionized. I hope to "factor-of-two" quantify this for crude system estimates.

At very high launch rates, this may someday cause huge problems, such as ram surface erosion and orbital decay for satellites, or diamagnetic reduction of Earth's magnetic field, increasing cosmic and CME radiation dose to the Earth's surface. Or not; no clue until I calculate.

Simple Rayleigh scattering peaks in the near ultraviolet, but the Rayleigh (1/λ⁴) law is accentuated by mid-UV resonances. Photoionization peaks just above the ionization energy. I have tables of space solar UV versus wavelength, and a few incomplete graphs of ionization cross sections, and static polarization for non-ionized molecules of interest.

But I would love to find the single numbers that someone else has computed from convolving these separate graphs ... or have measured empirically in simulated space solar UV. I don't trust my own (frightening!) estimates from partial data.

"Per molecular species" numbers might also be useful for computing the slow escape of the Martian atmophere, or water vapor from outer planet moons, but I have been unable to find simple numbers or references to them in journal papers about those processes. It is likely the numbers I want are in published papers, but I don't know the appropriate buzzwords to find them.

Photochemistry and collisions will create many more species, of course. The complete problem is huge; I'll worry about that after step one: starting with a few numbers and playing with roughly scaled, simplified models.

And if someone else wants to "snipe" the problem and publish first - be my guest. I just want to know, so I can invent mitigations if necessary.
 
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