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            bknpower: broken power law

A broken power law.

E Ebreak

E Ebreak

where:

par1 =

power law photon index for E < Ebreak

par2=Ebreak

break point for the energy in keV

par3=

power law photon index for E > Ebreak

norm=K

photons keV-1cm-2s-1 at 1 keV}

 

If POW_EMIN and POW_EMAX have been defined by the xset command then the norm becomes the flux in units of 10-12 ergs cm-2 s-1 over the energy range (POW_EMIN, POW_EMAX) keV unless POW_EMIN = POW_EMAX in which case the norm becomes the flux density in micro-Jansky at POW_EMIN keV. In these cases it is important that POW_EMIN and POW_EMAX lie within the energy range on which the model is being evaluated.

next up previous contents
Next: Bkn2pow Up: Additive Model Components Previous: Bexriv