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## power_law

Simple power law with a flat background

Parameter | Description | Units | Default value
--- | --- | --- | ---
scale | Scale factor or Volume fraction | None | 1
background | Source background | cm-1 | 0.001
power | Power law exponent | None | 4

The returned value is scaled to units of cm-1 sr-1, absolute scale.

This model calculates a simple power law with a flat background.

Definition

\[I(q) = \text{scale} \cdot q^{-\text{power}} + \text{background}\]

Note the minus sign in front of the exponent. The exponent power should therefore be entered as a positive number for fitting.

Also note that unlike many other models, scale in this model is NOT explicitly related to a volume fraction. Be careful if combining this model with other models.

Fig. 120 Figure 1: 1D plot corresponding to the default parameters of the model.

Source

`power_law.py`

References

None.

Authorship and Verification

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