Emission spectrum

# import packages
import nexus as nx
import numpy as np
import matplotlib.pyplot as plt

iron = nx.Material.Template(nx.lib.material.Fe)

# a 10 nm film is used for CEMS
layer_Fe = nx.Layer(id = "Fe layer",
                    material = iron,
                    thickness = 10)

site = nx.Hyperfine(magnetic_field = 33,
                    isotropic = True)

iron.hyperfine_sites = [site]

sample = nx.Sample(layers = [layer_Fe])

beam = nx.Beam(polarization = 0)

exp = nx.Experiment(beam = beam,
                       objects = [sample],
                       isotope = nx.lib.moessbauer.Fe57)

velocities = np.linspace(-10, 10, 512)

cem_spectrum = nx.EmissionSpectrum(experiment = exp,
                                    velocity = velocities)

intensity = cem_spectrum.Calculate()

plt.plot(velocities, intensity)
plt.xlabel('velocity (mm/s)')
plt.ylabel('intensity')
plt.show()

cem_spectrum.Plot()