Coulomb_cross_section¶
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plasmapy.formulary.collisions.
Coulomb_cross_section
(impact_param: Unit("m")) -> Unit("m2")¶ Cross section for a large angle Coulomb collision.
Parameters: impact_param (Quantity) – Impact parameter for the collision. Examples
>>> Coulomb_cross_section(7e-10*u.m) <Quantity 6.157...e-18 m2> >>> Coulomb_cross_section(0.5*u.m) <Quantity 3.141... m2>
Notes
The collisional cross-section (see [1] for a graphical demonstration) for a 90 degree Coulomb collision is obtained by
\[\sigma = \pi (2 * \rho_{\perp})^2\]where \(\rho_{\perp}\) is the distance of closest approach for a 90 degree Coulomb collision. This function is a generalization of that calculation. Please note that it is not guaranteed to return the correct results for small angle collisions.
Returns: The Coulomb collision cross section area. Return type: Quantity References
[1] https://en.wikipedia.org/wiki/Cross_section_(physics)#Collision_among_gas_particles