phot_class.models¶
The models module defines custom Source classes for modeling
supernovae with sncosmo.
Available Model Versions¶
There are multiple versions of a SN 1991bg-like model included in this package.
For information on how each version determines the flux for a given set of
parameters, see the documentation for the given source class. A modified
version of the Hsiao model is also available, which is the same as sncosmo’s
built in hsiao model (version 3.0) but with an added stretch parameter.
| Name | Version | Description |
|---|---|---|
| sn91bg | ‘salt2_phase’ (Default) | 1991bg model restricted to a phase similar to Salt 2.4 (extends from -18 to 50 days). |
| sn91bg | ‘hsiao_phase’ | 1991bg model restricted to a phase similar to Hsiao 3.0 (extends from -18 to 85 days). |
| sn91bg | ‘full_phase’ | 1991bg model extending over to full available phase range (-18 to 100 days). |
| hsiao_x1 | ‘3.0.x1’ | The same as sncosmo’s built in hsiao
model (version 3.0) but with an added stretch
parameter and limited to -18 to 85 days. |
Usage Example¶
>>> import sncosmo
>>> from matplotlib import pyplot as plt
>>>
>>> from phot_class import models
>>>
>>> # Make sncosmo aware of the 1991bg models
>>> models.register_sources()
>>>
>>> # Initialize a model
>>> source = sncosmo.get_source('sn91bg', version='phase_limited')
>>> model = sncosmo.Model(source=source)
>>>
>>> # Get more information on how the source determines flux
>>> print(help(source))
>>>
>>> # run the fit
>>> data = sncosmo.load_example_data()
>>> result, fitted_model = sncosmo.fit_lc(
>>> data, model,
>>> ['z', 't0', 'x0'], # parameters of model to vary
>>> bounds={'z':(0.3, 0.7)}) # bounds on parameters (if any)
>>>
>>> # Plot results
>>> fig = sncosmo.plot_lc(data, model=fitted_model, errors=result.errors)
>>> plt.show()