A quantum-mechanical investigation of O(3P) + CO scattering cross sections at superthermal collision energies

Abstract

The kinetics and energetic relaxation associated with collisions between fast and thermal atoms are of fundamental interest for escape and therefore also for the evolution of the Mars atmosphere. The total and differential cross-sections of fast O(3P) atom collisions with CO have been calculated from quantum mechanical calculations. The cross-sections are computed at collision energies from 0.4 to 5 eV in the center-of-mass frame relevant to the planetary science and astrophysics. All the three potential energy surfaces ( 3A′, 3A″ and 2 3A″ symmetry) of O(3P) + CO collisions separating to the atomic ground state have been included in calculations of cross-sections. The cross-sections are computed for all three isotopes of energetic O(3P) atoms collisions with CO. The isotope dependence of the cross-sections are compared. Our newly calculated data on the energy relaxation of O atoms and their isotopes with CO molecules will be very useful to improve the modeling of escape and energy transfer processes in the Mars’ upper atmosphere.

Non‐Thermal Oxygen Escape on Mars in the Presence of Gravity Waves

“…where θ is the mean scattering angle, m o is the O atom mass, and m is the weighted mass given by m = ∑ i N i σ i m i )/ ∑ i N i σ i ) , with N i , σ i and m i being the column density above the given altitude, the elastic collision crosssections with hot O atom from Lillis et al (2017), and mass for the ambient species i (CO 2 , O, N 2 , and CO), respectively. In the present study, we assume a common scattering angle of 20°based on the calculated differential (Chhabra et al, 2023;Gacesa et al, 2020;Kharchenko et al, 2000).…”

“…(2017), and mass for the ambient species i (CO 2 , O, N 2 , and CO), respectively. In the present study, we assume a common scattering angle of 20° based on the calculated differential cross sections for O–O, O–CO 2 , and O–CO collisions (Chhabra et al., 2023; Gacesa et al., 2020; Kharchenko et al., 2000).…”