.. only:: html
.. note::
:class: sphx-glr-download-link-note
Click :ref:`here ` to download the full example code
.. rst-class:: sphx-glr-example-title
.. _sphx_glr_modeling_gallery_spectral_plot_exp_cutoff_powerlaw_3fgl.py:
.. _exp-cutoff-powerlaw-3fgl-spectral-model:
Exponential Cutoff Powerlaw Spectral Model used for 3FGL
========================================================
This model parametrises a cutoff power law spectrum used for 3FGL.
It is defined by the following equation:
.. math::
\phi(E) = \phi_0 \cdot \left(\frac{E}{E_0}\right)^{-\Gamma}
\exp \left( \frac{E_0 - E}{E_{C}} \right)
Example plot
------------
Here is an example plot of the model:
.. code-block:: default
from astropy import units as u
import matplotlib.pyplot as plt
from gammapy.modeling.models import ExpCutoffPowerLaw3FGLSpectralModel, Models, SkyModel
energy_range = [0.1, 100] * u.TeV
model = ExpCutoffPowerLaw3FGLSpectralModel(
index=2.3 * u.Unit(""),
amplitude=4 / u.cm ** 2 / u.s / u.TeV,
reference=1 * u.TeV,
ecut=10 * u.TeV,
)
model.plot(energy_range)
plt.grid(which="both")
.. image:: /modeling/gallery/spectral/images/sphx_glr_plot_exp_cutoff_powerlaw_3fgl_001.png
:alt: plot exp cutoff powerlaw 3fgl
:class: sphx-glr-single-img
YAML representation
-------------------
Here is an example YAML file using the model:
.. code-block:: default
model = SkyModel(spectral_model=model, name="exp-cutoff-power-law-3fgl-model")
models = Models([model])
print(models.to_yaml())
.. rst-class:: sphx-glr-script-out
Out:
.. code-block:: none
components:
- name: exp-cutoff-power-law-3fgl-model
type: SkyModel
spectral:
type: ExpCutoffPowerLaw3FGLSpectralModel
parameters:
- name: index
value: 2.3
- name: amplitude
value: 4.0
unit: cm-2 s-1 TeV-1
- name: reference
value: 1.0
unit: TeV
frozen: true
- name: ecut
value: 10.0
unit: TeV
.. _sphx_glr_download_modeling_gallery_spectral_plot_exp_cutoff_powerlaw_3fgl.py:
.. only :: html
.. container:: sphx-glr-footer
:class: sphx-glr-footer-example
.. container:: sphx-glr-download sphx-glr-download-python
:download:`Download Python source code: plot_exp_cutoff_powerlaw_3fgl.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: plot_exp_cutoff_powerlaw_3fgl.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
`Gallery generated by Sphinx-Gallery `_