HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.

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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).

$\displaystyle A(E) = K (E/pivotE)^{(-a-b\log{(E/pivotE)})} $

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:

$\displaystyle A(E) = K ([E(1+z)]/pivotE)^{(-a-b\log{([E(1+z)]/pivotE)})} $

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  


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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.