gadem, vgadem, vvgadem, bgadem, bvgadem, bvvgadem: plasma emission, multi-temperature with gaussian distribution of emission measure.

A multi-temperature collisional-ionization equilibrium plasma emission model. The emission measure distribution is a gaussian with mean and sigma given by the first two model parameters. The switch parameter determines the spectrum will be calculated by running the mekal code, by interpolating on a pre-calculated mekal table, using the AtomDB data, or the SPEX data. The final two options are now preferred. See the cie model for further information and options.

For the gadem version, the abundance ratios are set by the abund command. The vgadem variant allows the user to define abundances for the more common elements. See the documentation on the cie model for information on using additional elements included in AtomDB and SPEX.

Velocity broadening can only be used with switch=2 or switch=3.

The parameters for gadem are:

par1 mean temperature for gaussian emission measure distribution
par2 sigma temperature for gaussian emission measure distribution
par3 nH (cm$^{-3}$)
par4 abundance relative to Solar
par5 redshift z
par6 switch (0 = calculate using MEKAL model; 1 = interpolate using MEKAL model; 2 = interpolate using AtomDB data, 3 interpolate using SPEX data)
norm Normalization

For the vgadem variant the parameters are:

par1 mean temperature for gaussian emission measure distribution
par2 sigma temperature for gaussian emission measure distribution
par3 nH (cm$^{-3}$)
par4–17 abundance for He, C, N, O, Ne, Na, Mg, Al, Si, S,Ar, Ca, Fe, Ni wrt Solar (defined by the abund command)
par18 redshift z
par19 switch (0 = calculate using MEKAL model; 1 = interpolate using MEKAL model; 2 = interpolate using AtomDB data, 3 interpolate using SPEX data)
norm Normalization

For the vvgadem variant the parameters are:

par1 mean temperature for gaussian emission measure distribution
par2 sigma temperature for gaussian emission measure distribution
par3 nH (cm$^{-3}$)
par4–33 abundance for He to Zn wrt Solar (defined by the abund command)
par34 redshift z
par35 switch (0 = calculate using MEKAL model; 1 = interpolate using MEKAL model; 2 = interpolate using AtomDB data, 3 interpolate using SPEX data)
norm Normalization

The parameters for the bgadem variant with a parameter for velocity broadening are:

par1 mean temperature for gaussian emission measure distribution
par2 sigma temperature for gaussian emission measure distribution
par3 nH (cm$^{-3}$)
par4 abundance relative to Solar
par5 redshift z
par6 Gaussian sigma for velocity broadening (km/s) (switch=2 or 3 only)
par7 switch (0 = calculate using MEKAL model; 1 = interpolate using MEKAL model; 2 = interpolate using AtomDB data, 3 interpolate using SPEX data)
norm Normalization

For the bvgadem variant with variable abundances and a parameter for velocity broadening the parameters are:

par1 mean temperature for gaussian emission measure distribution
par2 sigma temperature for gaussian emission measure distribution
par3 nH (cm$^{-3}$)
par4–17 abundance for He, C, N, O, Ne, Na, Mg, Al, Si, S,Ar, Ca, Fe, Ni wrt Solar (defined by the abund command)
par18 redshift z
par19 Gaussian sigma for velocity broadening (km/s) (switch=2 or 3 only)
par20 switch (0 = calculate using MEKAL model; 1 = interpolate using MEKAL model; 2 = interpolate using AtomDB data, 3 interpolate using SPEX data)
norm Normalization

For the bvvgadem variant with variable abundances and a parameter for velocity broadening the parameters are:

par1 mean temperature for gaussian emission measure distribution
par2 sigma temperature for gaussian emission measure distribution
par3 nH (cm$^{-3}$)
par4–33 abundance relative for He to Zn wrt Solar (defined by the abund command)
par34 redshift z
par35 Gaussian sigma for velocity broadening (km/s) (switch=2 or 3 only)
par36 switch (0 = calculate using MEKAL model; 1 = interpolate using MEKAL model; 2 = interpolate using AtomDB data, 3 interpolate using SPEX data)
norm Normalization

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Last modified: Friday, 23-Aug-2024 13:20:40 EDT