Last modified: December 2018

URL: http://cxc.harvard.edu/sherpa/ahelp/bbodyfreq.html
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AHELP for CIAO 4.11 Sherpa v1

bbodyfreq

Context: models

Synopsis

A one-dimensional Blackbody model (frequency).

Syntax

bbodyfreq

Description

This model can be used when the independent axis is in frequency space.


Example

>>> create_model_component("bbodyfreq", "mdl")
>>> print(mdl)

Create a component of the bbodyfreq model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.T        thawed        1e+06         1000        1e+10           
   mdl.ampl     thawed            1            0  3.40282e+38           

ATTRIBUTES

The attributes for this object are:

T

The temperature if the blackbody, in Kelvin.

ampl

The amplitude of the blackbody component.

Notes

The blackbody emission is calculated as a function of frequency (v) using Wien's law (hv >> kT):

f(v) = ampl * 2 * h * v^3 * exp(-h * v / (k * T)) / c^2

where T is the blackbody temperature in Kelvin, h is Planck's constant, k is Boltzmann's constant, and c the speed of light.


Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

See Also

models
bbody