Last modified: December 2023

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/blackbody.html
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AHELP for CIAO 4.16 Sherpa

blackbody

Context: models

Synopsis

Emission from a black body as a function of wavelength.

Syntax

blackbody

Description

It is for use when the independent axis is in Angstroms.


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.refer    frozen         5000  1.17549e-38  3.40282e+38  angstroms
   mdl.ampl     thawed            1  1.17549e-38  3.40282e+38  angstroms
   mdl.temperature thawed         3000  1.17549e-38  3.40282e+38     Kelvin

ATTRIBUTES

The attributes for this object are:

Attribute Definition
refer The reference point, in Angstroms.
ampl The amplitude of the emission; it is defined at the reference point but its numerical value there also depends on the temperature.
temperature The temperature in Kelvin.

Notes

The functional form of the model for points is:

f(x) = ampl * g(refer) / g(x)

g(x) = x^5 * (exp(1.438786E8 / temperature / x) - 1)

and for integrated data sets the low-edge of the grid is used.


Bugs

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

See Also

models
bremsstrahlung