def stars_with_mechanical_luminosity(self, particles):
result = ParticlesOverlay(particles)
def lmech_function(temperature, mass, luminosity, radius):
T = temperature.value_in(units.K)
M = mass.value_in(units.MSun)
L = luminosity.value_in(units.LSun)
R = radius.value_in(units.RSun)
# Reimers wind below 8000K
mass_loss = (4.0e-13 | units.MSun / units.yr) * L * R / M
# ... wind above 8000K
i = numpy.where(temperature > 8000 | units.K)[0]
mass_loss[i] = (10**-24.06 | units.MSun / units.yr) * (
L**2.45 * M**(-1.1) * T.clip(1000, 8.0e4)**(1.31))
t4 = numpy.log10(T * 1.0e-4).clip(0.0, 1.0)
v_terminal = (30 + 4000 * t4) | units.km / units.s
return 0.5 * mass_loss * v_terminal**2
result.add_calculated_attribute(
"mechanical_luminosity",
lmech_function,
attributes_names=["temperature", "mass", "luminosity", "radius"])
result.L_mech = result.mechanical_luminosity
result.E_mech = (0.0 | units.Myr) * result.L_mech
result.E_mech_last_feedback = result.E_mech
result.previous_mass = result.mass # Store the mass of the star at the last moment of feedback
return result
