- electronScatter
Electron Scatter¶
Works with a VSimPD license. Collision of the form
A scattering process similar to binaryElastic
,
but optimized for the specific case where one of the scattering species
is an electron. The electronScatter
process is inelastic, for an elastic
electron scattering process, use Binary Elastic.
A generator of 2 product particles to model electron scattering off of a neutral/ion. Can be isotropic or anisotropic following the Vahedi-Surendra algorithm [VS95].
In the Vahedi-Surendra algorithm, the incident electron loses small percentage of its energy and is scattered after the collision. The scattered electron energy, \(\epsilon_{sc}\), is computed to be:
where:
\(\epsilon_{inc}\) is the incident electron energy,
\(m_e\) is the mass of the incident electron,
\(M_0\) is the mass of the “A” species in the equation above,
\(\chi\) is the scattering angle given by:
The azimuthal scattering angle is given by:
In the above equations \(R_1\) and \(R_2\) are two random numbers uniformly distributed between 0 and 1.
Any RxnProcess Block block which points to a
productGenerator of kind = electronScatter
should have the
Reactants
and Products
in the order:
reactants = [electron speciesA]
products = [electron speciesA]
electronScatter Attributes¶
- scatterType (string, required, default = VS)
The isotropy of the electron scatter. Can be
isotropic
orVS
for a non-isotropic scattering following the algorithm presented by Vahedi and Surendra (see above).
- randomSeed (int, optional, default: random int)
Manually set a random seed used to determine the final velocities of the product particles.
The default is to choose a random seed at run time. To produce identical simulations, advanced users may want to manually set a seed. It is recommended not to include this parameter so that a different random number will be generated for each run.
Example electronScatter Block¶
<RxnProductGenerator productGenerator>
kind = electronScatter
#scatterType = VS
#randomSeed = 423
</RxnProductGenerator>