Simple Flavor Mixing (Obsolete)

Illustrate very basic neutrino flavor mixing in supernova neutrinos using the SimpleMixing class in ASTERIA.

import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt

import astropy.units as u

from asteria import config, source
from asteria.neutrino import Flavor
from asteria.oscillation import SimpleMixing

mpl.rc('font', size=16)

Load CCSN Neutrino Model

Load a neutrino luminosity model (see YAML documentation).

conf = config.load_config('../../data/config/test.yaml')
ccsn = source.initialize(conf)

Basic Mixing

Set up the mixing class, which only depends on \(\theta_{12}\).

See nu-fit.org for current values of the PMNS mixing angles.

# Use theta_12 in degrees.
# To do: explicitly use astropy units for input.
mix = SimpleMixing(33.8)

Mix the Flavors

Apply the mixing and plot the resulting flux curves for the unmixed case and assuming the normal and inverted neutrino mass hierarchies.

fig, axes = plt.subplots(1, 3, figsize=(13,3.5), sharex=True, sharey=True)

ax1, ax2, ax3 = axes
t = np.linspace(-0.1, 1, 201) * u.s

# UNMIXED
for ls, flavor in zip(["-", "--", "-.", ":"], Flavor):
    flux = ccsn.get_flux(t, flavor)

    ax1.plot(t, flux, ls, lw=2, label=flavor.to_tex(), alpha=0.7)
    ax1.set_title("Unmixed")
# plt.yscale('log')
# plt.ylim(3e51, 5e53)
ax1.set(xlabel='time - $t_{bounce}$ [s]',
        ylabel='flux')
ax1.legend()

# NORMAL MIXING
nu_list1 = []
i = 0
for flavor in Flavor:
    flux = ccsn.get_flux(t, flavor)
    nu_list1.append(flux)

nu_new1 = mix.normal_mixing(nu_list1)

for ls, i, flavor in zip(["-", "--", "-.", ":"], range(len(nu_new1)), Flavor):
    new_flux1 = nu_new1[i]
    ax2.plot(t, new_flux1, ls, lw=2, alpha=0.7, label=flavor.to_tex())
    ax2.set_title(label="Normal Mixing")

ax2.set(xlabel='time - $t_{bounce}$ [s]',
        ylabel='flux')

ax2.legend()

# INVERTED MIXING
nu_list2 = []
i = 0
for flavor in Flavor:
    flux = ccsn.get_flux(t, flavor)
    nu_list2.append(flux)

nu_new2 = mix.inverted_mixing(nu_list1)

for ls, i, flavor in zip(["-", "--", "-.", ":"], range(len(nu_new2)), Flavor):
    new_flux2 = nu_new2[i]
    ax3.plot(t, new_flux2, ls, lw=2, alpha=0.7, label=flavor.to_tex())
    ax3.set_title(label="Inverted Mixing")

ax3.set(xlabel='time - $t_{bounce}$ [s]',
        ylabel='flux')
ax3.legend()


fig.tight_layout();