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Constant Spectral Model

This model takes a constant value along the spectral range.

$$\phi(E) = k$$

Example plot

Here is an example plot of the model:

from astropy import units as u
import matplotlib.pyplot as plt
from gammapy.modeling.models import ConstantSpectralModel, Models, SkyModel

energy_range = [0.1, 100] * u.TeV
model = ConstantSpectralModel(const="1 / (cm2 s TeV)")
model.plot(energy_range)
plt.grid(which="both")

YAML representation

Here is an example YAML file using the model:

model = SkyModel(spectral_model=model, name="constant-model")
models = Models([model])

print(models.to_yaml())

Out:

components:
-   name: constant-model
    type: SkyModel
    spectral:
        type: ConstantSpectralModel
        parameters:
        -   name: const
            value: 1.0
            unit: cm-2 s-1 TeV-1