def main():
o, arguments = new_option_parser().parse_args()
double_star, stars = make_binary_star(
o.mprim, o.msec, o.semimajor_axis, o.eccentricity,
)
end_time = 1000.0 | units.yr
evolve_model(end_time, double_star, stars)
def main():
o, arguments = new_option_parser().parse_args()
# override binary star parameters
o.semimajor_axis = 1 | units.au
o.eccentricity = 0.5
o.mprim = o.msec = 30 | units.MSun
double_star, stars = make_binary_star(
o.mprim,
o.msec,
o.semimajor_axis,
o.eccentricity,
)
stars.kaps = o.kaps
stars.taulag = o.taulag
# override star parameters
stars.radius = 25 | units.RSun
stars[0].kaps = 0.15
stars[0].taulag = 1e4 | units.s
stars[1].kaps = 0.0
stars[1].taulag = 0.0 | units.s
# this circularizes in 5e4 yr
end_time = 1e4 | units.yr
evolve_model(end_time, double_star, stars)
def main():
m1, m2 = 80 | units.MSun, 55 | units.MSun
a0 = 4000 | units.RSun
e0 = 0.9
o, arguments = new_option_parser(M_default=m1,
m_default=m2,
a_default=a0,
e_default=e0).parse_args()
double_star, stars = make_binary_star(
o.mprim,
o.msec,
o.semimajor_axis,
o.eccentricity,
)
end_time = 1000.0 | units.yr
evolve_model(end_time, double_star, stars)
def test_binary_evolution(a0=0.3 | units.au,
e0=0.6,
m1=60 | units.MSun,
m2=40 | units.MSun,
t0=0 | units.yr,
tend=3 | units.Myr,
dt_out=1000 | units.yr,
dt_kick_fP=0.1):
###################
### BSE ###
###################
bse = BSE()
bse.parameters.metallicity = 0.02
bse.parameters.neutron_star_mass_flag = 3
stars_bse = Particles(2)
stars_bse[0].mass = m1
stars_bse[1].mass = m2
mu = stars_bse.mass.sum() * constants.G
P0 = np.pi * (a0 * a0 * a0 / mu).sqrt()
print("P0:", P0.as_string_in(units.yr))
print("a0:", a0.as_string_in(units.au))
print("e0:", e0)
binaries = Particles(1)
binary = binaries[0]
binary.semi_major_axis = a0
binary.eccentricity = e0
binary.child1 = stars_bse[0]
binary.child2 = stars_bse[1]
bse.particles.add_particles(stars_bse)
bse.binaries.add_particles(binaries)
from_bse_to_model = bse.particles.new_channel_to(stars_bse)
from_bse_to_model.copy()
from_bse_to_model_binaries = bse.binaries.new_channel_to(binaries)
from_bse_to_model_binaries.copy()
###################
### NBODY ###
###################
converter = nbody_system.nbody_to_si(1 | units.MSun, 1 | units.au)
directcode = Hermite(converter)
binary_nbd, stars_nbd = make_binary_star(m1, m2, a0, e0)
directcode.particles.add_particle(stars_nbd)
from_nbody_to_model = directcode.particles.new_channel_to(stars_nbd)
from_model_to_nbody = stars_nbd.new_channel_to(directcode.particles)
##################
### BEGIN LOOP ###
##################
t = t0
t_next_out = t0 + dt_out
dt_kick = P0 * dt_kick_fP * 10000000
data = []
while t < tend:
t = t + dt_kick
bse.evolve_model(t)
from_bse_to_model_binaries.copy()
from_bse_to_model.copy()
if t >= t_next_out:
data.append(
(t.value_in(units.yr), binary.child1.mass.value_in(units.MSun),
binary.child2.mass.value_in(units.MSun),
binary.child1.radius.value_in(units.RSun),
binary.child2.radius.value_in(units.RSun),
binary.semi_major_axis.value_in(units.RSun),
binary.eccentricity))
t_next_out = t + dt_out
print("{:g}%".format(t / tend * 100), end="\r")
bse.stop()
#######################
###### PLOTTING #######
#######################
data = np.array(data)
time = data[:, 0]
mass1 = data[:, 1]
mass2 = data[:, 2]
radius1 = data[:, 3]
radius2 = data[:, 4]
semi = data[:, 5]
ecc = data[:, 6]
peri = semi * (1 - ecc)
figure = plt.figure(figsize=(16, 7))
plot = figure.add_subplot(1, 2, 1)
plot.plot(time, mass1, label='m1')
plot.plot(time, mass2, label='m2')
plot.set_xlabel('Time [yr]')
plot.set_ylabel('Mass [MSun]')
plot.legend(loc='best')
plot = figure.add_subplot(1, 2, 2)
plot.plot(time, radius1, label='R1')
plot.plot(time, radius2, label='R2')
plot.plot(time, semi, label='semi BSE', c="blue")
plot.plot(time, peri, label='peri BSE', c="blue", ls="-.")
plot.set_xlabel('Time [yr]')
plot.set_ylabel('R [RSun]')
plot.legend()
plt.show()