def multiscreen_tau(sample, d2g=0.009, scatm=ss.makeScatmodel("RG", "Drude")):
result = []
for walker in sample:
logNHu, logNHs, a_u, a_s, p_u, p_s, x_s = walker
MDu, MDs = np.power(10.0, logNHu) * c.mp() * d2g, np.power(10.0, logNHs) * c.mp() * d2g
da_u, da_s = (a_u - AMIN) / 10.0, (a_s - AMIN) / 10.0
Udust = dust.Dustdist(rad=np.arange(AMIN, a_u + da_u, da_u), p=p_u)
Sdust = dust.Dustdist(rad=np.arange(AMIN, a_s + da_s, da_s), p=p_s)
Ukappa = ss.Kappascat(E=1.0, dist=dust.Dustspectrum(rad=Udust, md=MDu), scatm=scatm).kappa[0]
Skappa = ss.Kappascat(E=1.0, dist=dust.Dustspectrum(rad=Sdust, md=MDs), scatm=scatm).kappa[0]
result.append(Ukappa * MDu + Skappa * MDs)
return np.array(result)
def sample_logMD(sample, d2g=0.009, replace=False, mscreen=False):
if mscreen:
nhtot = np.power(10.0, sample[:, 2]) + np.power(10.0, sample[:, 3])
logmd = np.log10(nhtot * c.mp() * d2g)
if replace:
result = np.copy(sample)
result[:, 2] = sample[:, 2] + np.log10(c.mp() * d2g)
result[:, 3] = sample[:, 3] + np.log10(c.mp() * d2g)
return result
else:
logmd = sample[:, 0] + np.log10(c.mp() * d2g)
if replace:
result = np.copy(sample)
result[:, 0] = logmd
return result
return logmd
def sample_tau(sample, d2g=0.009, mscreen=False):
result = []
for walker in sample:
if mscreen:
x1, x2, logNH1, logNH2, amax, p = walker
nhtot = np.power(10.0, logNH1) + np.power(10.0, logNH2)
md = nhtot * c.mp() * d2g
else:
logNH, amax, p = walker
md = np.power(10.0, logNH) * c.mp() * d2g
da = (amax - AMIN) / 100.0
DD = dust.Dustdist(rad=np.arange(AMIN, amax + da, da), p=p)
DS = dust.Dustspectrum(rad=DD, md=md)
KK = ss.Kappascat(E=1.0, dist=DS).kappa[0]
result.append(KK * md)
return np.array(result)
def DiscreteISM( halo, xg=0.5, NH=1.0e20, d2g=0.009 ):
"""
FUNCTION DiscreteISM( halo, xg=0.5, NH=1.0e20, d2g=0.009 )
MODIFIES halo.htype, halo.dist, halo.taux, halo.intensity
----------------------------------------------------------------------------
halo : Halo object
xg : float : distance FROM source / distance between source and observer
NH : float : column density [cm^-2]
d2g : float : dust-to-gass mass ratio
"""
E0 = halo.energy
alpha = halo.alpha
scatm = halo.scatm
md = NH * c.mp() * d2g
halo.htype = GalHalo( xg=xg, NH=NH, d2g=d2g, ismtype='Screen' )
halo.dist = dust.Dustspectrum( rad=halo.rad, md=md )
thscat = alpha / xg
if type(halo.rad) == dust.Grain:
dsig = ss.Diffscat( theta=thscat, a=halo.dist.a, E=E0, scatm=scatm ).dsig
intensity = np.power( xg, -2.0 ) * dsig * halo.dist.nd
elif type(halo.rad) == dust.Dustdist:
avals = halo.dist.a
intensity = []
for i in range( len(alpha) ):
iatemp = np.zeros( shape=( len(avals),len(alpha) ) )
for j in range( len(avals) ):
dsig = ss.Diffscat( theta=thscat, a=avals[j], E=E0, scatm=scatm ).dsig
iatemp[j,:] = np.power(xg,-2.0) * dsig
intensity.append( c.intz( avals, iatemp[:,i] * halo.dist.nd ) )
intensity = np.array( intensity )
else:
print '%% Must input type dust.Grain or dust.Dustdist'
intensity = np.zeros( np.size(xvals) )
halo.intensity = intensity * np.power( c.arcs2rad(), 2 ) # arcsec^-2
halo.taux = ss.Kappascat( E=halo.energy, scatm=halo.scatm, dist=halo.dist ).kappa * md
def rp( self, E ):
mm1 = self.rho / ( 2.0*c.mp() ) * c.re()/(2.0*np.pi) * np.power( c.kev2lam()/E , 2 )
return mm1+1
import numpy as np
import matplotlib.pyplot as plt
print('importing...')
import sigma_scat as ss
import dust
import constants as c
print('setting input...')
# column density
NH = 1.e21
# dust-to-gas ratio
d2g = 0.009
# use proton mass to get dust column mass
dust_mass = NH * c.mp() * d2g
# energy range to evaluate over (in keV)
ERANGE = np.power( 10.0, np.arange(-0.6,1.0,0.005) )
MD = dust_mass * 10.0 # for N_H = 1.e22
# define densities
# g cm^-3; see Draine book
RHO_SIL, RHO_GRA, RHO_AVG = 3.8, 2.2, 3.0
print('defining dust distributions...')
# dust radius range to compute (in um)
# up to 0.25 um
MRN_RANGE = np.arange(0.005,0.25001,0.05)
# larger range going up to 1.5 um
BIG_RANGE = np.arange(0.005, 1.5, 0.05)
def UniformISM( halo, NH=1.0e20, d2g=0.009, nx=1000, usepathdiff=False ):
"""
FUNCTION UniformISM( halo, NH=1.0e20, d2g=0.009, nx=1000, usepathdiff=False )
MODIFIES halo.htype, halo.dist, halo.taux, halo.intensity
----------------------------------------------------------------------------
halo : Halo object
NH : float : column density [cm^-2]
d2g : float : dust-to-gass mass ratio
nx : int : number of values to use in integration
usepathdiff : boolean : True = use extinction due to path difference e^(-tau*path_diff)
"""
E0 = halo.energy
alpha = halo.alpha
scatm = halo.scatm
md = NH * c.mp() * d2g
halo.htype = GalHalo( NH=NH, d2g=d2g, ismtype='Uniform' )
halo.dist = dust.Dustspectrum( rad=halo.rad, md=md )
halo.taux = ss.Kappascat( E=halo.energy, scatm=halo.scatm, dist=halo.dist ).kappa * md
dx = 1.0 / nx
xvals = np.arange( 0.0, 1.0, dx ) + dx
#--- Single grain case ---
if type( halo.rad ) == dust.Grain:
intensity = np.array([])
for al in alpha:
thscat = al / xvals # np.size(thscat) = nx
dsig = ss.Diffscat( theta=thscat, a=halo.dist.a, E=E0, scatm=scatm ).dsig
delta_tau = 0.0
if usepathdiff:
print 'Using path difference'
delta_x = path_diff( al, xvals )
delta_tau = halo.taux * delta_x
print np.max( delta_x )
itemp = np.power( xvals, -2.0 ) * dsig * halo.dist.nd * np.exp( -delta_tau )
intensity = np.append( intensity, c.intz( xvals, itemp ) )
#--- Dust distribution case ---
elif type( halo.rad ) == dust.Dustdist:
avals = halo.dist.a
intensity = np.array([])
for al in alpha:
thscat = al / xvals # np.size(thscat) = nx
iatemp = np.array([])
for aa in avals:
dsig = ss.Diffscat( theta=thscat, a=aa, E=E0, scatm=scatm ).dsig
delta_tau = 0.0
if usepathdiff:
print 'Using path difference'
delta_x = path_diff( al, xvals )
delta_tau = halo.taux * delta_x
print max( delta_x )
dtemp = np.power( xvals, -2.0 ) * dsig * np.exp( -delta_tau )
iatemp = np.append( iatemp, c.intz( xvals, dtemp ) )
intensity = np.append( intensity, c.intz( avals, halo.dist.nd * iatemp ) )
else:
print '%% Must input type dust.Grain or dust.Dustdist'
intensity = np.zeros( np.size(xvals) )
# Set the halo intensity
halo.intensity = intensity * np.power( c.arcs2rad(), 2 ) # arcsec^-2