[FLASH-USERS] Several questions about the Spitzer resistivity used in Flash

[lizy]

Dear Flash developer, hello

I have some questions about the Spitzer resistivity used in Flash, and I sincerely hope to receive your answers.
 
1. Should Spitzer resistivity be applicable to completely ionized substances? So, is it unreasonable to study a metal that is driven from room temperature to a fully ionized state (such as in zpinch)? After all, the temperature in the early stage was too low, and the ionization level was very low.
 
2. The Spitzer resistivity expression I found is: η=1.03 × e − 4 Zbar ln ll/tele_eV * * 1.5 (ohm * m)
 
And you provided two resistors here, the original text in the program is as follows:
 
resPerpLoc = 8.21876126127e5*zbar*ll/tele_eV**1.5  !! In CGS -- Here tele has to be in eV
 
resPar = resPerpLoc/1.96
 
And there is the following annotation: This formula is only valid when the magnetic field is strong (and only for hydrogen).
 
2.1. Are the two resistivity values you provided the components of vertical current and horizontal current resistivity? If I want to calculate the  Isotropic aluminum , should I only consider resPar? When  the unit system is converted, is the conversion parameter in the flash documentation also the ratio between the parameter to be converted and resPar?
 
2.2. As mentioned above, can the resistivity formula you provided only calculate hydrogen? Are the coefficients in front of the Spitzer resistivity different for different substances?
 
2.3. The issue of unit system conversion. What I found is an MKS unit system, while the one provided in Flash should be in the form of UnitSystem="none", right? How does the coefficient not match the parameters provided in the documentation? not be 4π/c^2,,or 1/μ0？？？
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