Low energy collisions between ground-state oxygen atoms

Tully, Catherine; Johnson, R. E.

doi:10.1016/s0032-0633(01)00002-2

“…Kharchenko et al (2000) found that the statistically averaged (over channels) cross sections are highly peaked at small scattering angles, χ , for energies of few eV. This agrees with the results of Tully and Johnson (2001). They also show that the Landau-Schiff approximation reproduced the statistically averaged (over scattering angles) cross sections as function of the energy.…”

Section: Monte Carlo Methodssupporting

confidence: 72%

“…The isotropic assumption is the main limitation of the hard sphere approach. An accurate description of the O-O collisions needs to use 18 separate ground state potential curves for O 2 (Tully and Johnson 2001). Kharchenko et al (2000) derived scattering cross sections between two oxygen atoms by solving the Schrodinger equation of the relative motion of two oxygen atoms in a potential field for different channels corresponding to different states of the O 2 molecule.…”

Section: Monte Carlo Methodsmentioning

confidence: 99%

Modeling of Venus, Mars, and Titan

Kallio

¹

,

Chaufray

²

,

Modolo

³

et al. 2011

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Increased computer capacity has made it possible to model the global plasma and neutral dynamics near Venus, Mars and Saturn's moon Titan. The plasma interactions at Venus, Mars, and Titan are similar because each possess a substantial atmosphere but lacks a global internally generated magnetic field. In this article three self-consistent plasma models are described: the magnetohydrodynamic (MHD) model, the hybrid model and the fully kinetic plasma model. are also described. In particular, we describe the pros and cons of each model approach. Results from simulations are presented to demonstrate the ability of the models to capture the known plasma and neutral dynamics near the three objects.

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“…Hodges (2000) and Valeille et al (2009a) (Tully and Johnson 2001). Kharchenko et al (2000) derived scattering cross sections between two oxygen atoms by solving the Schrodinger equation of the relative motion of two oxygen atoms in a potential field for different channels corresponding to different states of the O 2 molecule.…”

Section: Monte Carlo Methodsmentioning

confidence: 99%

Modeling of Venus, Mars, and Titan

Kallio

¹

,

Chaufray

²

,

Modolo

³

et al. 2011

Space Sciences Series of ISSI

View full text Add to dashboard Cite

Increased computer capacity has made it possible to model the global plasma and neutral dynamics near Venus, Mars and Saturn's moon Titan. The plasma interactions at Venus, Mars, and Titan are similar because each possess a substantial atmosphere but lacks a global internally generated magnetic field. In this article three self-consistent plasma models are described: the magnetohydrodynamic (MHD) model, the hybrid model and the fully kinetic plasma model. are also described. In particular, we describe the pros and cons of each model approach. Results from simulations are presented to demonstrate the ability of the models to capture the known plasma and neutral dynamics near the three objects.

show abstract

“…Simulations and transport equations using realistic potentials give mean escape depths (N es σ d ) ∼ 1.3 (Johnson 1994, Appendix A). Detailed calculations of the O + O collision, averaging over the ground state multiplet (Kharchenko et al 2000;Tully and Johnson 2001), give σ d = 1.3 × 10 −15 cm 2 for a 2 eV O moving in an O thermosphere or N es ∼ 10 15 O/cm 2 . Since σ d decreases slowly with increasing energy, N es should be averaged over the hot particle energy distribution.…”

Section: Introductionmentioning

confidence: 99%