:py:mod:`protoRT.compute_opacities`
===================================

.. py:module:: protoRT.compute_opacities

.. autoapi-nested-parse::

   Created on Fri Nov 29 12:01:01 2024

   @author: daniel



Module Contents
---------------


Functions
~~~~~~~~~

.. autoapisummary::

   protoRT.compute_opacities.dsharp_model



.. py:function:: dsharp_model(p, wavelength, grain_sizes, bin_approx=False)

   Compute dust absorption and scattering opacities using the DSHARP model.

   This function supports both monodisperse and polydisperse grain size distributions,
   allowing for either a full grain size integration or a binned approximation (`bin_approx`).

   Opacities are computed using the DSHARP dust opacity tables (Birnstiel et al. 2018) and
   are valid for wavelengths in the range 1e-5 to 10 cm and grain sizes from 1e-5 to 100 cm.
   It assumes a constant internal density across all grain sizes of 1.675 (g/cm³), as per the adopted dust model.

   .. rubric:: Notes

   When `bin_approx=True`, the grain size distribution is discretized into bins such that:
   - The first bin always starts at 1e-5 cm (minimum DSHARP grain size).
   - Each bin's `a_max` is given by the input `grain_sizes`.
   - Each subsequent bin begins slightly above the previous bin edge (offset by 1e-10 cm) to avoid overlap and mass overestimation.

   If `bin_approx=False`, a single grain size is assumed (monodisperse case).

   .. warning::

      Opacities cannot be computed for exactly 1e-5 cm unless a small positive offset is applied
      (e.g., `1e-5 + 1e-10` cm), due to our binning strategy.

   :param p: Power-law index of the grain size distribution; n(a) ∝ a^(-p).
   :type p: float
   :param wavelength: Wavelength at which to evaluate the opacities [cm].
   :type wavelength: float
   :param grain_sizes: Array of maximum grain sizes for each bin [cm].
   :type grain_sizes: list or ndarray
   :param bin_approx: If True, enables the binned approximation for polydisperse models.
                      Default is False (monodisperse case).
   :type bin_approx: bool, optional

   :returns: * **absorption_opacities** (*np.ndarray*) -- Absorption opacities (cm²/g) for each grain bin.
             * **scattering_opacities** (*np.ndarray*) -- Scattering opacities (cm²/g) for each grain bin.
             * **grain_size_bins** (*np.ndarray*) -- Array of (a_min, a_max) tuples for each grain size bin [cm].