def mass_loss_loon05(L,Teff):
Mdot = -<NUM_LIT> + np.log10(old_div(L,<NUM_LIT>**<NUM_LIT:4>)) -<NUM_LIT>*np.log10(old_div(Teff,<NUM_LIT>))<EOL>return Mdot<EOL>
mass loss rate van Loon etal (2005).

Parameters
----------
L : float
    L in L_sun.
Teff : float
    Teff in K.

Returns
-------
Mdot
    Mdot in Msun/yr

Notes
-----
ref: van Loon etal 2005, A&A 438, 273