[Last Change: 15 Feb 2012 (rev 4)]

Simple Source Spectrum Definitions

A simple spectrum definition takes one of two forms:
  1. A single floating point number, indicating a monochromatic source with the given energy in keV with a flux of 1.0 photon/s/cm2:
    spectrum = 1.49
  2. A list of one or more specifications encoded as a Lua table:
    spectrum = { spec1, spec2, ... }
The available specifications are:

Monochromatic, default flux of 1.0 photon/s/cm2

The specification takes the form of a number, which is the energy in keV. The flux is set at 1.0 photon/s/cm2.

For example,
spectrum = { 1.49 }

Monochromatic, specific flux

A list containing two elements, the first the energy in keV and the second the flux in in photon/s/cm2.

For example,
spectrum = { { 1.49, 0.2 } }

Picket Fence

The spectrum is composed of δ-functions at specified energies read from a file in RDB format.The specification is a table with the following entries:
name type description default
file string name of file  
energy string name of column containing energy in keV "energy"
flux string name of column containing flux in photons/s/cm2 "flux"
type string must be set to "picket"  
For example,

spectrum = { { file = "picket.rdb", type = "picket" } }

Flat

The spectrum is flat across an energy range. The specification is a table with the following entries:

name type description default
emin number minimum energy in range, inclusive  
emax number maximum energy in range, exclusive  
flux number flux in photons/s/cm2 1.0
type string must be set to "flat"  
For example,
spectrum = { { emin = 0.2, emax = 10.0, type = "flat" } }

File

The spectrum is read from a file containing a binned spectrum. The specification is a table with the following entries:

name type description default
file string name of file  
format string format of file. must be "rdb"  
emin string name of column containing minimum bin energy in keV, inclusive "emin"
emax string name of column containing maximum bin energy in keV, exclusive "emax"
flux string name of column containing flux "flux"
units string units of flux. one of: "ergs/s/cm2/kev", "kev/s/cm2/kev", or "photons/s/cm2"  
scale number factor by which to scale the spectrum 1.0
For example,
spectrum = { { file = "spectrum.rdb", units = "ergs/s/cm2/kev", scale = 0.5, format = "rdb" } }

Presently, only RDB format files are accepted.
 
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