def plot_points():
papers = [
dict(tag='hegra', label='HEGRA (2004)'),
dict(tag='magic', label='MAGIC (TODO)'),
# 'veritas',
dict(tag='hess', label='H.E.S.S. (2006)')
]
table_all = load_crab_flux_points()
# import IPython; IPython.embed()
# Plot flux points
for paper in papers:
mask = table_all['paper'] == paper['tag']
table = table_all[mask]
print('paper: {}, points: {}'.format(paper, len(table)))
x = table['energy'].to('TeV').data
y = table['energy_flux'].data
yerr_lo = table['energy_flux_err_lo'].data
yerr_hi = table['energy_flux_err_hi'].data
plt.errorbar(
x,
y,
yerr=(yerr_lo, yerr_hi),
linewidth=2,
fmt='o',
capsize=0,
label=paper['label'],
)
def __init__(self):
table = load_crab_flux_points(component='nebula')
table = table[table['paper'] == 'fermi_33months']
self.name = 'fermi'
self.x = Quantity(table['energy']).to('TeV').value
self.y = Quantity(table['energy_flux']).to('erg cm-2 s-1').value
self.staterror = Quantity(table['energy_flux_err']).to('erg cm-2 s-1').value
"""Plot Crab pulsar and nebula spectral energy distribution (SED).
http://gammapy.readthedocs.org/en/latest/tutorials/crab_mwl_sed/index.html
"""
import numpy as np
import matplotlib.pyplot as plt
import astropy.units as u
from gammapy.datasets import load_crab_flux_points
from gammapy.spectrum import crab_flux
# Plot flux points
for component in ['pulsar', 'nebula']:
table = load_crab_flux_points(component=component)
x = table['energy'].data
y = table['energy_flux'].data
yerr_lo = table['energy_flux_err_lo'].data
yerr_hi = table['energy_flux_err_hi'].data
plt.errorbar(x, y, yerr=(yerr_lo, yerr_hi), fmt='o', label=component)
# Plot SED model
energy = np.logspace(2, 8, 100) * u.MeV
flux = u.Quantity(crab_flux(energy.to('TeV').value), 'cm^-2 s^-1 TeV^-1')
energy_flux = (energy ** 2 * flux).to('erg cm^-2 s^-1')
plt.plot(energy.value, energy_flux.value, label='Meyer (2010) model', lw=666)
plt.title('Crab (SED)')
plt.xlim((3e-14, 3e8))
plt.ylim((3e-13, 3e-7))
plt.xlabel('Energy (MeV)')
plt.ylabel('E^2 dN/dE (erg cm^-2 s^-1)')