.. _radiated_powers:

Radiated Powers
===============

Sampling and plotting total and stage resolved radiated powers with the ADAS
subscription package.

.. code-block:: pycon

   >>> import numpy as np
   >>> import matplotlib.pyplot as plt

   >>> from cherab.core.atomic import neon
   >>> from cherab.core.math import sample2d_grid
   >>> from cherab.adas import ADAS


   >>> print("Testing total radiation for Neon.")

   >>> atomic_data = ADAS()

   >>> electron_density = 1.e19
   >>> electron_temperature = np.logspace(0, 4, 41)

   >>> # Obtaining total radiation using ADAS405 code (equilibrium balance)
   >>> total_rad = atomic_data.total_radiated_power(neon)
   >>> total_power = sample2d_grid(total_rad, electron_density, electron_temperature).squeeze()

   >>> # Obtaining fractional abundance using ADAS405 code
   >>> fractional_abundance = np.zeros((neon.atomic_number + 1, electron_temperature.size))
   >>> for charge, abundance in enumerate(fractional_abundance):
   >>>     fraction = atomic_data.fractional_abundance(neon, charge)
   >>>     abundance[:] = sample2d_grid(fraction, electron_density, electron_temperature).squeeze()

   >>> # Obtaining line and continuum radiation
   >>> line_power = np.zeros((neon.atomic_number, electron_temperature.size))
   >>> continuum_power = np.zeros((neon.atomic_number, electron_temperature.size))
   >>> for charge in range(neon.atomic_number):
   >>>     line_rad = atomic_data.line_radiated_power_rate(neon, charge)
   >>>     continuum_rad = atomic_data.continuum_radiated_power_rate(neon, charge + 1)
   >>>     line_power[charge] = sample2d_grid(line_rad, electron_density, electron_temperature).squeeze() * fractional_abundance[charge]
   >>>     continuum_power[charge] = sample2d_grid(continuum_rad, electron_density, electron_temperature).squeeze() * fractional_abundance[charge + 1]

   >>> plt.figure()
   >>> plt.plot(electron_temperature, total_power, '-k', label='Total radiation')
   >>> plt.plot(electron_temperature, continuum_power.sum(0), ls=':', color='k', label='Recombination + Bremsstr.')
   >>> plt.plot(electron_temperature, line_power.sum(0), ls=':', color='0.7', label='Total line radiation')
   >>> for charge in range(line_power.shape[0]):
   >>>     plt.plot(electron_temperature, line_power[charge], ls='--', label='Ne(+{}) line radiation'.format(charge))
   >>> plt.xscale('log')
   >>> plt.yscale('log')
   >>> plt.ylim(1.e-39, 1.e-31)
   >>> plt.xlabel("Electron Temperature (eV)")
   >>> plt.ylabel("Power function (W m^3)")
   >>> plt.title("Neon radiation")
   >>> plt.legend(ncol=2, fontsize=9)
   >>> plt.show()

.. figure:: stage_resolved_radiation.png
   :align: center
   :width: 450px