def find_gamma(energy, jnu, Z=1):
""" Find the photoionization rate / 1e12 given the spectrum as a
function of energy in Rydbergs.
in units of photons / s.
This is copying JFH's code in cldy_cuba_jfh.pro.
"""
sigma_nu = photo_cross_section_hydrogenic(energy, Z=Z)
# output is in units of 1e-12
integrand = 4. * pi * jnu * sigma_nu / hplanck * 1e12
log_energy = np.log10(energy)
isort = np.argsort(log_energy)
# don't understand why this works...
gamma = np.log(10) * simps(integrand[isort], x=log_energy[isort])
return gamma
def find_gamma(energy, jnu, Z=1):
""" Find the photoionization rate / 1e12 given the spectrum as a
function of energy in Rydbergs.
in units of photons / s.
This is copying JFH's code in cldy_cuba_jfh.pro.
"""
sigma_nu = photo_cross_section_hydrogenic(energy, Z=Z)
# output is in units of 1e-12
integrand = 4. * pi * jnu * sigma_nu / hplanck * 1e12
log_energy = np.log10(energy)
isort = np.argsort(log_energy)
# don't understand why this works...
gamma = np.log(10) * simps(integrand[isort], x=log_energy[isort])
return gamma
sigma_nu = photo_cross_section_hydrogenic(energy, Z=Z)
# output is in units of 1e-12
integrand = 4. * pi * jnu * sigma_nu / hplanck * 1e12
log_energy = np.log10(energy)
isort = np.argsort(log_energy)
# don't understand why this works...
gamma = np.log(10) * simps(integrand[isort], x=log_energy[isort])
return gamma
if 0:
# They match, woot!
iHeII = 2
E = 10**np.linspace(1, 5, 100) * u.eV
s, Eth, Emax = sigma_Verner96(E, iHeII)
s2 = photo_cross_section_hydrogenic(E.to(u.rydberg).value, Z=2)
plt.loglog(E.value, s.value*1e18)
plt.loglog(E.value, s2*1e18)
show()
if 1:
# measure the photoionization rate, which is the integral of the
# ionizing field * the cross section.
# from McQuinn and Worseck 2014MNRAS.440.2406M
# eta = 0.43 * gamma_HI / gamma_HeII
# Faucher-Giguere 2009
gamma_HI = 0.861e-12
print 'gamma HeII'
# output is in units of 1e-12
integrand = 4. * pi * jnu * sigma_nu / hplanck * 1e12
log_energy = np.log10(energy)
isort = np.argsort(log_energy)
# don't understand why this works...
gamma = np.log(10) * simps(integrand[isort], x=log_energy[isort])
return gamma
if 0:
# They match, woot!
iHeII = 2
E = 10**np.linspace(1, 5, 100) * u.eV
s, Eth, Emax = sigma_Verner96(E, iHeII)
s2 = photo_cross_section_hydrogenic(E.to(u.rydberg).value, Z=2)
plt.loglog(E.value, s.value * 1e18)
plt.loglog(E.value, s2 * 1e18)
show()
if 1:
# measure the photoionization rate, which is the integral of the
# ionizing field * the cross section.
# from McQuinn and Worseck 2014MNRAS.440.2406M
# eta = 0.43 * gamma_HI / gamma_HeII
# Faucher-Giguere 2009
gamma_HI = 0.861e-12
print 'gamma HeII'