c6mekl, c6vmekl, c6pmekl, c6pvmkl: differential emission measure using Chebyshev representations with multi-temperature mekal
c6mekl is a multi-temperature mekal model using sixth-order Chebyshev polynomial for the differential emission measure. The DEM is not constrained to be positive.. The switch parameter determines whether the mekal code will be run to calculate the model spectrum for each temperature or whether the model spectrum will be interpolated from a pre-calculated table. The former is slower but more accurate. The reference for this model is Singh et al. (1996, ApJ, 456, 766).
c6pmekl differs by using the exponential of the 6th order Chebyshev polynomial
c6mekl and c6pmekl use abundances relative to the Solar abundances set by the abund command
The variants c6vmkl and c6pvmkl with polynomial and exponential polynomial respectively allow the user to specify 14 elemental abundance.
For c6mekl and c6pmkl the parameters are:
par1-6 |
Chebyshev polynomial coefficients |
par7 |
H density (cm-3) |
par8 |
abundance wrt to Solar |
par9 |
Redshift |
par10 |
0 calculate |
1 interpolate |
|
2 interpolate using APEC model |
|
norm |
where DA is the angular size distance to the source (cm), ne is the electron density (cm-3), and nH is the hydrogen density (cm-3) |
While for c6vmkl and c6vpmkl the parameters are:
par1-6 |
Chebyshev polynomial coefficients |
par7 |
H density (cm-3) |
par8-21 |
Abundances of He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni wrt Solar (defined by the abund command) |
par22 |
Redshift |
par23 |
0 calculate |
1 interpolate |
|
2 interpolate using APEC model |
|
norm |
where DA is the angular size distance to the source (cm), ne is the electron density (cm-3), and nH is the hydrogen density (cm-3) |