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cempow, vcempow, bcempow, bvcempow: plasma emission, multi-temperature using a power-law emission measure

A multi-temperature plasma emission model. Emission measures follow a power-law in temperature ( $dEM = (T/T_{max})^{\alpha-1}dT/T_{max}$).The switch parameter determines whether the spectrum is 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 cempow and bcempow versions, the abundance ratios are set by the abund command. The vcempow and bvcempow variants allow the user to define the abundances. The reference for this model is Singh et al. (1996, ApJ, 456, 766).

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

For cempow the parameters are:

par1 $\alpha$, index for power-law emissivity function
par2 $T_{max}$, maximum temperature
par3 $n_H$ (cm$^{-3}$
par4 Abundance relative to Solar
par5 z, redshift
par6 Switch (0 = calculate using mekal, 1 = interpolate using mekal, 2 = use AtomDB data, 3 = use SPEX data).
norm Normalization

For the vcempow variant the parameters are:

par1 $\alpha$, index for power-law emissivity function
par2 $T_{max}$, maximum temperature
par3 $n_H$ (cm$^{-3}$
par4–17 Abundances of He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni wrt Solar (defined by the abund command)
par18 z, redshift
par19 Switch (0 = calculate using mekal, 1 = interpolate using mekal, 2 = use AtomDB data, 3 = use SPEX data).
norm Normalization

For bcempow the parameters are:

par1 $\alpha$, index for power-law emissivity function
par2 $T_{max}$, maximum temperature
par3 $n_H$ (cm$^{-3}$
par4 Abundance relative to Solar
par5 z, redshift
par6 Gaussian sigma for velocity broadening (km/s) (switch=2 only)
par7 Switch (0 = calculate using mekal, 1 = interpolate using mekal, 2 = use AtomDB data, 3 = use SPEX data).
norm Normalization

For the bvcempow variant the parameters are:

par1 $\alpha$, index for power-law emissivity function
par2 $T_{max}$, maximum temperature
par3 $n_H$ (cm$^{-3}$
par4–17 Abundances of He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni wrt Solar (defined by the abund command)
par18 z, redshift
par19 Gaussian sigma for velocity broadening (km/s) (switch=2 only)
par20 Switch (0 = calculate using mekal, 1 = interpolate using mekal, 2 = use AtomDB data, 3 = use SPEX data).
norm Normalization
next up previous contents
Next: cflow: cooling flow Up: Additive Model Components Previous: cemekl, cevmkl: plasma emission,   Contents