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&GAS: MAGBOLTZ


frac

The fraction of the gas mixture taken up by a component.

The sum of the fractions is normalised - in the examples, fractions usually add up to 1 or to 100, but this is not mandatory.

[Each fraction is 0 by default.]


ELECTRIC-FIELD

You can either ask Magboltz to compute the transport properties for a range of electric fields or for a single electric field.

It is advisable to choose the electric field range sufficiently large to cover all fields present in your chamber, rather than to rely on INTERPOLATIONS and EXTRAPOLATIONS.

[By default E ranges from 100 V/cm to 100000 V/cm in 20 logarithmically spaced steps.]


B-FIELD

A magnetic field can have a major impact on the direction of motion of electrons, as well as on the transverse diffusion. These effects depend not only on the magnetic field strength, but also on the ANGLE between the electric and magnetic fields.

You can either ask Magboltz to compute the transport properties for a range of magnetic fields or for a single magnetic field.

If you ask for only 1 magnetic field strength and only 1 angle between E and B, then Magboltz will generate a 1-dimensional table for which you have greater control over the INTERPOLATIONS and EXTRAPOLATIONS methods.

These parameters can not be used if there is no magnetic field.

[If the magnetic field can be determined to be constant or zero, then Magboltz by default only computes a table for the magnetic field that is present in the chamber. If the B field is not constant, but of known range, then Magboltz will by default be run for 6 magnetic fields ranging from the minimum field to the maximum field present in the chamber. In all other cases, it will compute tables for 0, 1, 2, 3, 4 and 5 T.]


ANGLE

Electron transport properties in the presence of a magnetic field depend not only on the magnetic field strength but also on the angle between the electric and the magnetic field.

You can either ask Magboltz to compute the transport properties for a range of angles between E and B or for a single angle between the 2 fields:

If you ask for only 1 magnetic field strength and only 1 angle between E and B, then Magboltz will generate a 1-dimensional table for which you have greater control over the INTERPOLATIONS and EXTRAPOLATIONS methods.

These parameters can not be used if there is no magnetic field.

[Magboltz will, if B is non-zero, by default be asked to compute tables for an angle of 0, 30, 60 and 90 degrees between the E and B field.]


PLOT-DISTRIBUTION-FUNCTIONS

Requests for each E, and if applicable each B and E-B orientation, plots of the electron distribution functions.

This option potentially generates a lot of output.

[The option is off by default.]


ANALYTIC-INTEGRATION

Calls the analytic version of Magboltz, also known as Magboltz 1.

This option, which is not default, is provided for backwards compatibility only - Monte Carlo integration is currently believed to be superior.

Several anisotropic gasses can not be used when analytic integration is requested.

Additional information on:
  


MONTE-CARLO-INTEGRATION

Calls the Monte Carlo version of Magboltz, also known as Magboltz 2.

[This is default.]

Additional information on:
  
 


MOBILITY

Magboltz only computes the electron transport properties in gasses. This keyword enables adding an ion mobility to the tables.

This format only allows for mobilities that are constant or depend in a simple way on E/p. In the latter case, the argument of MOBILITY should be a function with EP as variable.

ADD provides a similar functionality, and can in addition be used if the mobility is available in tabular form.

The unit of mobility in Garfield is cm2/microsec.V.

[By default: no mobility.]


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Formatted on 0100-09-02 at 06:56.