Synopsis
UV extinction curve: Fitzpatrick and Massa 1988.
Syntax
fm
Description
The UV extinction is calculated using [1] . This model is intended to be used to modify another model (e.g. by multiplying the two together). It is for use when the independent axis is in Angstrom.
Example
>>> create_model_component("fm", "mdl")
>>> print(mdl)Create a component of the fm model and display its default parameters. The output is:
mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.ebv thawed 0.5 -3.40282e+38 3.40282e+38 mdl.x0 thawed 4.6 -3.40282e+38 3.40282e+38 mdl.width thawed 0.06 -3.40282e+38 3.40282e+38 mdl.c1 thawed 0.2 -3.40282e+38 3.40282e+38 mdl.c2 thawed 0.1 -3.40282e+38 3.40282e+38 mdl.c3 thawed 0.02 -3.40282e+38 3.40282e+38 mdl.c4 thawed 0.1 -3.40282e+38 3.40282e+38
ATTRIBUTES
The attributes for this object are:
| Attribute | Definition |
|---|---|
| ebv | E(B-V) |
| x0 | Position of the Drude bump. |
| width | Width of the Drude bump. |
| c1 | The intercept of the linear term. |
| c2 | The slope of the linear term. |
| c3 | Normalization of the Drude bump. |
| c4 | Normalization of the FUV curvature. |
Notes
When evaluated on a binned grid, the lower-edges of the bins are used for the calculation.
References
- [1] Fitzpatrick and Massa 1988 http://adsabs.harvard.edu/abs/1988ApJ...328..734F
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.