next up previous contents
Next: Raymond Up: Additive Model Components Previous: Powerlaw

pshock, vpshock:  plane-parallel shocked plasma, constant temperature

Constant temperature, plane-parallel shock plasma model. The references for this model can be found under the description of the equil model.  Several versions are available.  To switch between them use the xset neivers command. xset neivers 1.0 gives the version from xspec v11.1, xset neivers 1.1 uses updated calculations of ionization fractions using dielectronic recombination rates from Mazzotta et al (1998), and xset neivers 2.0 uses the same ionization fractions as 1.1 but uses APED to calculate the resulting spectrum, and xset neivers 3.0 uses the beta release from AtomDB 3.0. Note that versions 1.x have no emission from Ar. The default is version 3.0.

The vpshock variant allows the user to set the abundances of the most common elements and vvpshock allows the user to set the abundances of all elements with Z<=30.

 

Parameters for the pshock version are:

 

par1

plasma temperature (keV)

par2

Metal abundances (He fixed at cosmic). The elements included are C, N, O, Ne, Mg, Si, S, Ar, Ca, Fe, Ni in ratios set by the abund command.

par3

Lower limit on ionization timescale in units of s/cm3.

par4

Upper limit on ionization timescale in units of s/cm3.

par5

redshift z

norm

 where DA is the angular diameter distance to the source (cm), and ne , nH (cm-3) are the electron and hydrogen densities respectively.

 

Parameters for vpshock are:

 

par1

plasma temperature (keV)

par2

H abundance (should take values of 0 or 1 to switch on and off free-free continuum).

par3-par14

Abundances for He, C, N, O, Ne, Mg, Si, S, Ar, Ca, Fe, Ni wrt the solar as defined by the abund command.

par15

Lower limit on ionization timescale in units of s/cm3.

par16

Upper limit on ionization timescale in units of s/cm3.

par17

redshift z

norm

 where DA is the angular diameter distance to the source (cm) , and ne , nH (cm-3) are the electron and hydrogen densities respectively.

 

Parameters for vvpshock are:

 

par1

plasma temperature (keV)

par2

H abundance (should take values of 0 or 1 to switch on and off free-free continuum).

par3-par31

Abundances for all elements with 2 <= Z <= 30 wrt Solar (defined by the abund command)

par32

Lower limit on ionization timescale in units of s/cm3.

par33

Upper limit on ionization timescale in units of s/cm3.

par34

redshift z

norm

 where DA is the angular diameter distance to the source (cm) , and ne , nH (cm-3) are the electron and hydrogen densities respectively.

 

 

next up previous contents
Next: Raymond Up: Additive Model Components Previous: Powerlaw