def add_pwn_parameters(table):
"""Add PWN parameters to the table.
TODO: document
"""
# Some of the computations (specifically `pwn.radius`) aren't vectorised
# across all parameters; so here we loop over source parameters explicitly
results = []
for idx in range(len(table)):
age = table["age"].quantity[idx]
E_SN = table["E_SN"].quantity[idx]
n_ISM = table["n_ISM"].quantity[idx]
P0_birth = table["P0_birth"].quantity[idx]
b_psr = table["B_PSR"].quantity[idx]
# Compute properties
pulsar = Pulsar(P0_birth, b_psr)
snr = SNRTrueloveMcKee(e_sn=E_SN, n_ISM=n_ISM)
pwn = PWN(pulsar, snr)
r_out_pwn = pwn.radius(age).to_value("pc")
results.append(dict(r_out_pwn=r_out_pwn))
# Add columns to table
table["r_out_PWN"] = Column(
[_["r_out_pwn"] for _ in results], unit="pc", description="PWN outer radius"
)
return table
def add_pulsar_parameters(
table,
B_mean=12.05,
B_stdv=0.55,
P_mean=0.3,
P_stdv=0.15,
random_state="random-seed",
):
"""Add pulsar parameters to the table.
For the initial normal distribution of period and logB can exist the following
Parameters: B_mean=12.05[log Gauss], B_stdv=0.55, P_mean=0.3[s], P_stdv=0.15
Parameters
----------
random_state : {int, 'random-seed', 'global-rng', `~numpy.random.RandomState`}
Defines random number generator initialisation.
Passed to `~gammapy.utils.random.get_random_state`.
"""
random_state = get_random_state(random_state)
# Read relevant columns
age = table["age"].quantity
# Draw the initial values for the period and magnetic field
def p_dist(x):
return np.exp(-0.5 * ((x - P_mean) / P_stdv) ** 2)
p0_birth = draw(0, 2, len(table), p_dist, random_state=random_state)
p0_birth = Quantity(p0_birth, "s")
log10_b_psr = random_state.normal(B_mean, B_stdv, len(table))
b_psr = Quantity(10 ** log10_b_psr, "G")
# Compute pulsar parameters
psr = Pulsar(p0_birth, b_psr)
p0 = psr.period(age)
p1 = psr.period_dot(age)
p1_birth = psr.P_dot_0
tau = psr.tau(age)
tau_0 = psr.tau_0
l_psr = psr.luminosity_spindown(age)
l0_psr = psr.L_0
# Add columns to table
table["P0"] = Column(p0, unit="s", description="Pulsar period")
table["P1"] = Column(p1, unit="", description="Pulsar period derivative")
table["P0_birth"] = Column(p0_birth, unit="s", description="Pulsar birth period")
table["P1_birth"] = Column(
p1_birth, unit="", description="Pulsar birth period derivative"
)
table["CharAge"] = Column(tau, unit="yr", description="Pulsar characteristic age")
table["Tau0"] = Column(tau_0, unit="yr")
table["L_PSR"] = Column(l_psr, unit="erg s-1")
table["L0_PSR"] = Column(l0_psr, unit="erg s-1")
table["B_PSR"] = Column(
b_psr, unit="Gauss", description="Pulsar magnetic field at the poles"
)
return table
"""Plot spin frequency of the pulsar with time."""
import numpy as np
import matplotlib.pyplot as plt
from astropy.units import Quantity
from gammapy.astro.source import Pulsar
t = Quantity(np.logspace(0, 6, 100), "yr")
pulsar = Pulsar(P_0=Quantity(0.01, "s"), logB=12)
plt.plot(t.value, 1 / pulsar.period(t).cgs.value)
plt.xlabel("time [years]")
plt.ylabel("frequency [1/s]")
plt.ylim(1e0, 1e2)
plt.loglog()
plt.show()
"""Plot spin frequency of the pulsar with time."""
import numpy as np
import matplotlib.pyplot as plt
from astropy.units import Quantity
from gammapy.astro.source import Pulsar
t = Quantity(np.logspace(0, 6, 100), "yr")
pulsar = Pulsar(P_0=Quantity(0.01, "s"), B="1e12 G")
plt.plot(t.value, 1 / pulsar.period(t).cgs.value)
plt.xlabel("time [years]")
plt.ylabel("frequency [1/s]")
plt.ylim(1e0, 1e2)
plt.loglog()
plt.show()
"""Plot spin frequency of the pulsar with time."""
import numpy as np
import matplotlib.pyplot as plt
from astropy.units import Quantity
from gammapy.astro.source import Pulsar
t = Quantity(np.logspace(0, 6, 100), "yr")
pulsar = Pulsar(P_0=Quantity(0.01, "s"), logB=12)
plt.plot(t.value, 1 / pulsar.period(t).cgs.value)
plt.xlabel("time [years]")
plt.ylabel("frequency [1/s]")
plt.ylim(1e0, 1e2)
plt.loglog()
plt.show()
# Licensed under a 3-clause BSD style license - see LICENSE.rst
import scipy.integrate
from numpy.testing import assert_allclose
from astropy.table import Table
from astropy.units import Quantity
from gammapy.astro.source import Pulsar, SimplePulsar
from gammapy.utils.testing import assert_quantity_allclose
pulsar = Pulsar()
time = Quantity([1e2, 1e4, 1e6, 1e8], "yr")
def get_atnf_catalog_sample():
data = """
NUM NAME Gl Gb P0 P1 AGE BSURF EDOT
1 J0006+1834 108.172 -42.985 0.693748 2.10e-15 5.24e+06 1.22e+12 2.48e+32
2 J0007+7303 119.660 10.463 0.315873 3.60e-13 1.39e+04 1.08e+13 4.51e+35
3 B0011+47 116.497 -14.631 1.240699 5.64e-16 3.48e+07 8.47e+11 1.17e+31
7 B0021-72E 305.883 -44.883 0.003536 9.85e-20 5.69e+08 5.97e+08 8.79e+34
8 B0021-72F 305.899 -44.892 0.002624 6.45e-20 6.44e+08 4.16e+08 1.41e+35
16 J0024-7204O 305.897 -44.889 0.002643 3.04e-20 1.38e+09 2.87e+08 6.49e+34
18 J0024-7204Q 305.877 -44.899 0.004033 3.40e-20 1.88e+09 3.75e+08 2.05e+34
21 J0024-7204T 305.890 -44.894 0.007588 2.94e-19 4.09e+08 1.51e+09 2.65e+34
22 J0024-7204U 305.890 -44.905 0.004343 9.52e-20 7.23e+08 6.51e+08 4.59e+34
28 J0026+6320 120.176 0.593 0.318358 1.50e-16 3.36e+07 2.21e+11 1.84e+32
"""
return Table.read(data, format="ascii")
def test_SimplePulsar_atnf():
"""Test functions against ATNF pulsar catalog values"""
"""Plot spin frequency of the pulsar with time."""
import numpy as np
import matplotlib.pyplot as plt
from astropy.units import Quantity
from gammapy.astro.source import Pulsar
t = Quantity(np.logspace(0, 6, 100), 'yr')
pulsar = Pulsar(P_0=Quantity(0.01, 's'), logB=12)
plt.plot(t.value, 1 / pulsar.period(t).cgs.value, color='b')
plt.xlabel('time [years]')
plt.ylabel('frequency [1/s]')
plt.ylim(1E0, 1E2)
plt.loglog()
plt.show()