logpar, zlogpar: log-parabolic blazar model

logpar is a power-law with an index which varies with energy as a log parabola. The zlogpar variant computes a redshifted spectrum. See for instance Massaro et al. (2004).

par1 | a, slope at the pivot energy |

par2 | b, curvature term |

par3 | pivotE, fixed pivot energy (best near low end of energy range). |

norm= K |

For zlogpar the formula and corresponding parameters are:

par1 | a, slope at the pivot energy |

par2 | b, curvature term |

par3 | pivotE, fixed pivot energy (best near low end of energy range). |

par4 | z, redshift |

norm= K |