&GAS: PARAMETERS


A

  The number of nucleons per molecule.

  This parameter is used only to compute the cluster size
  distribution if you didn't enter such a distribution
  yourself.

E-MOST-PROBABLE

  The most probable, not the mean, energy loss in eV per cm.

  This parameter is used only to compute the cluster size
  distribution if you didn't enter such a distribution
  yourself or asked HEED to do this for you.

  You may also type MOST-PROBABLE-ENERGY-LOSS.

E-PAIR

  The energy in eV needed to ionise a molecule.

  This parameter is used only to compute the cluster size
  distribution if you didn't enter such a distribution
  yourself or asked HEED to do this for you.

  You may also type PAIR-CREATION-ENERGY.

MEAN

  The average number of clusters per cm.

  This parameter is used extensively, e.g. for the
  calculation of arrival time distributions, for the
  signal calculation and also to compute a cluster
  size distribution if such a distribution was not
  entered directly via a CLUSTER statement.

  You may also type N-MEAN.

RHO

  The density of the gas in g/cm**3.

  This parameter is used only to compute the cluster size
  distribution if you didn't enter such a distribution
  yourself or asked HEED to do this for you.

Z

  The nuclear charge of the molecule.

  This parameter is used only to compute the cluster size
  distribution if you didn't enter such a distribution
  yourself or asked HEED to do this for you.

sigma

  The transverse and longitudinal diffusion coefficients for ions
  of the type expected to be produced in your chamber, filled with
  the gas being entered.

  These coefficients are used for Monte Carlo drift line integration.

  The diffusion coefficients should be expressed in cm of
  diffusion for 1 cm of drift.

  [Both diffusion coefficients default to 0.]

Keyword index. Formatted on 10/11/98.