vice.milkyway.default_mass_loading
==================================

The default mass loading factor as a function of galactocentric
radius in kpc.

**Signature**: vice.milkyway.default_mass_loading(rgal)

Parameters
----------
rgal : real number
	Galactocentric radius in kpc.

Returns
-------
eta : real number
	The mass loading factor at that radius, defined by:

	.. math:: \eta(r) = (y_\text{O}^\text{CC}) / Z_\text{O}^\odot
		10^{0.08(r - 4\text{ kpc}) - 0.3} - 0.6

	where :math:`Z_\text{O}^\odot` is the solar abundance by mass of
	oxygen and :math:`y_\text{O}^\text{CC}` is the IMF-averaged CCSN
	yield of oxygen. While these values are customizable through
	``vice.solar_z`` and ``vice.yields.ccsne.settings``, this function
	assumes a value of :math:`Z_\text{O}^\odot` = 0.00572 (Asplund et
	al. 2009 [1]_) and :math:`y_\text{O}^\text{CC}` = 0.015 (Johnson &
	Weinberg 2020 [2]_, Johnson et al. 2021 [3]_).

.. seealso:: vice.milkyway.mass_loading

Example Code
------------
>>> import vice
>>> vice.milkyway.default_mass_loading(0)
0.029064576665950193
>>> vice.milkyway.default_mass_loading(8)
2.1459664721614495

.. [1] Asplund et al. (2009), ARA&A, 47, 481
.. [2] Johnson & Weinberg (2020), MNRAS, 498, 1364
.. [3] Johnson et al. (2021), MNRAS, 508, 4484