def Qsca( self, E, a=1.0, cm=cmi.CmDrude() ):
if np.size(a) != 1:
print 'Error: Must specify only 1 value of a'
return
a_cm = a * c.micron2cm() # cm -- Can only be a single value
lam = c.kev2lam() / E # cm -- Can be many values
x = 2.0 * np.pi * a_cm / lam
mm1 = cm.rp(E) - 1 + 1j * cm.ip(E)
return 2.0 * np.power( x, 2 ) * np.power( np.abs(mm1), 2 )
def __init__( self ):
self.cmtype = 'Silicate'
D03vals = c.restore( os.path.join(CMROOT,'CM_D03.pysav')) # look up file
lamvals = D03vals['Sil_lam']
revals = D03vals['Sil_re']
imvals = D03vals['Sil_im']
lamEvals = c.kev2lam() / c.micron2cm() / lamvals # keV
self.rp = interp1d( lamEvals, revals )
self.ip = interp1d( lamEvals, imvals )
def __init__( self ):
self.cmtype = 'Silicate'
D03file = find_cmfile('CM_D03.pysav')
D03vals = c.restore(D03file) # look up file
lamvals = D03vals['Sil_lam']
revals = D03vals['Sil_re']
imvals = D03vals['Sil_im']
lamEvals = c.kev2lam() / c.micron2cm() / lamvals # keV
self.rp = interp1d( lamEvals, revals )
self.ip = interp1d( lamEvals, imvals )
def Diff( self, theta, E=1.0, a=1.0, cm=cmi.CmDrude() ): # cm^2 ster^-1
if np.size(a) != 1:
print 'Error: Must specify only 1 value of a'
return
if np.logical_and( np.size(E) > 1, # If more than 1 energy is specified
np.size(E) != np.size(theta) ): # theta must be of the same size
print 'Error: If specifying > 1 energy, must have same number of values for theta'
return
a_cm = a * c.micron2cm() # cm -- Can only be a single value
lam = c.kev2lam() / E # cm
x = 2.0 * np.pi * a_cm / lam
mm1 = cm.rp(E) + 1j * cm.ip(E) - 1
thdep = 2./9. * np.exp( -np.power( theta/self.Char(a=a, E=E) , 2 ) / 2.0 )
dsig = 2.0 * np.power(a_cm,2) * np.power(x,4) * np.power( np.abs(mm1),2 )
return dsig * thdep
def sample_extinction(sample, lam, isample, NA=20, d2g=0.009, scatm=ss.makeScatmodel("RG", "Drude")):
energy = c.kev2lam() / lam # lam must be in cm to get keV
logMD = sample_logMD(sample)
MD = np.power(10.0, logMD)
result = []
for i in isample:
logNH, amax, p = sample[i]
print "logNH =", logNH, "\tamax =", amax, "\tp =", p
da = (amax - AMIN) / np.float(NA)
dist = dust.Dustdist(rad=np.arange(AMIN, amax + da, da), p=p)
spec = dust.Dustspectrum(rad=dist, md=MD[i])
kappa = ss.Kappascat(E=energy, dist=spec, scatm=scatm).kappa
result.append(1.086 * MD[i] * kappa)
return result
def get_Q( self, E, qtype, a ):
try :
data = parse_PAH( self.type )
except :
print 'ERROR: Cannot find PAH type', self.type
return
try :
qvals = np.array( data[a][qtype] )
wavel = np.array( data[a]['w(micron)'] )
except :
print 'ERROR: Cannot get grain size', a, 'for', self.stype
return
# Wavelengths were listed in reverse order
q_interp = interp1d( wavel[::-1], qvals[::-1] )
E_um = ( c.kev2lam() / E ) * 1.e4 # cm to um
return q_interp( E_um )
def __init__( self, size='big', orient='perp' ):
# size : string ('big' or 'small')
# : 'big' gives results for 0.1 um sized graphite grains at 20 K [Draine (2003)]
# : 'small' gives results for 0.01 um sized grains at 20 K
# orient : string ('perp' or 'para')
# : 'perp' gives results for E-field perpendicular to c-axis
# : 'para' gives results for E-field parallel to c-axis
#
self.cmtype = 'Graphite'
self.size = size
self.orient = orient
D03file = find_cmfile('CM_D03.pysav') # look up file
D03vals = c.restore(D03file) # read in index values
if size == 'big':
if orient == 'perp':
lamvals = D03vals['Cpe_010_lam']
revals = D03vals['Cpe_010_re']
imvals = D03vals['Cpe_010_im']
if orient == 'para':
lamvals = D03vals['Cpa_010_lam']
revals = D03vals['Cpa_010_re']
imvals = D03vals['Cpa_010_im']
if size == 'small':
if orient == 'perp':
lamvals = D03vals['Cpe_001_lam']
revals = D03vals['Cpe_001_re']
imvals = D03vals['Cpe_001_im']
if orient == 'para':
lamvals = D03vals['Cpa_001_lam']
revals = D03vals['Cpa_001_re']
imvals = D03vals['Cpa_001_im']
lamEvals = c.kev2lam() / c.micron2cm() / lamvals # keV
self.rp = interp1d( lamEvals, revals )
self.ip = interp1d( lamEvals, imvals )
def getQs( self, a=1.0, E=1.0, cm=cmi.CmDrude(), getQ='sca', theta=None ): # Takes single a and E argument
if np.size(a) > 1:
print 'Error: Can only specify one value for a'
return
indl90 = np.array([]) # Empty arrays indicate that there are no theta values set
indg90 = np.array([])
# Do not have to check if theta != None throughout calculation
s1 = np.array([])
s2 = np.array([])
pi = np.array([])
pi0 = np.array([])
pi1 = np.array([])
tau = np.array([])
amu = np.array([])
if theta != None:
if np.size(E) > 1 and np.size(E) != np.size(theta):
print 'Error: If more than one E value specified, theta must have same size as E'
return
if np.size( theta ) == 1:
theta = np.array( [theta] )
theta_rad = theta * c.arcs2rad()
amu = np.abs( np.cos(theta_rad) )
indl90 = np.where( theta_rad < np.pi/2.0 )
indg90 = np.where( theta_rad >= np.pi/2.0 )
nang = np.size( theta )
s1 = np.zeros( nang, dtype='complex' )
s2 = np.zeros( nang, dtype='complex' )
pi = np.zeros( nang, dtype='complex' )
pi0 = np.zeros( nang, dtype='complex' )
pi1 = np.zeros( nang, dtype='complex' ) + 1.0
tau = np.zeros( nang, dtype='complex' )
refrel = cm.rp(E) + 1j*cm.ip(E)
x = ( 2.0 * np.pi * a*c.micron2cm() ) / ( c.kev2lam()/E )
y = x * refrel
ymod = np.abs(y)
nx = np.size( x )
# *** Series expansion terminated after NSTOP terms
# Logarithmic derivatives calculated from NMX on down
xstop = x + 4.0 * np.power( x, 0.3333 ) + 2.0
test = np.append( xstop, ymod )
nmx = np.max( test ) + 15
nmx = np.int32(nmx)
nstop = xstop
# nmxx = 150000
# if (nmx > nmxx):
# print 'error: nmx > nmxx=', nmxx, ' for |m|x=', ymod
# *** Logarithmic derivative D(J) calculated by downward recurrence
# beginning with initial value (0.,0.) at J=NMX
d = self.create_d(nx,nmx,y)
# *** Riccati-Bessel functions with real argument X
# calculated by upward recurrence
psi0 = np.cos(x)
psi1 = np.sin(x)
chi0 = -np.sin(x)
chi1 = np.cos(x)
xi1 = psi1 - 1j * chi1
qsca = 0.0 # scattering efficiency
gsca = 0.0 # <cos(theta)>
s1_ext = 0
s2_ext = 0
s1_back = 0
s2_back = 0
pi_ext = 0
pi0_ext = 0
pi1_ext = 1
tau_ext = 0
p = -1.0
for n in np.arange( np.max(nstop) )+1: # for n=1, nstop do begin
en = n
fn = (2.0*en+1.0)/ (en* (en+1.0))
# for given N, PSI = psi_n CHI = chi_n
# PSI1 = psi_{n-1} CHI1 = chi_{n-1}
# PSI0 = psi_{n-2} CHI0 = chi_{n-2}
# Calculate psi_n and chi_n
# *** Compute AN and BN:
#*** Store previous values of AN and BN for use
# in computation of g=<cos(theta)>
if n > 1:
an1 = an
bn1 = bn
if nx > 1:
ig = nstop >= n
psi = np.zeros( nx )
chi = np.zeros( nx )
psi[ig] = (2.0*en-1.0) * psi1[ig]/x[ig] - psi0[ig]
chi[ig] = (2.0*en-1.0) * chi1[ig]/x[ig] - chi0[ig]
xi = psi - 1j * chi
an = np.zeros( nx, dtype='complex' )
bn = np.zeros( nx, dtype='complex' )
an[ig], bn[ig] = scattering_utils.an_bn(d[ig,n],refrel[ig],en,x[ig],psi[ig],psi1[ig],xi[ig],xi1[ig])
# an[ig], bn[ig] = self.an_bn(d[ig,n],refrel[ig],en,x[ig],psi[ig],psi1[ig],xi[ig],xi1[ig])
else:
psi = (2.0*en-1.0) * psi1/x - psi0
chi = (2.0*en-1.0) * chi1/x - chi0
xi = psi - 1j * chi
an = ( d[0,n]/refrel + en/x ) * psi - psi1
an = an / ( ( d[0,n]/refrel + en/x ) * xi - xi1 )
bn = ( refrel*d[0,n] + en / x ) * psi - psi1
bn = bn / ( ( refrel*d[0,n] + en/x ) * xi - xi1 )
# *** Augment sums for Qsca and g=<cos(theta)>
# NOTE from LIA: In IDL version, bhmie casts double(an)
# and double(bn). This disgards the imaginary part. To
# avoid type casting errors, I use an.real and bn.real
# Because animag and bnimag were intended to isolate the
# real from imaginary parts, I replaced all instances of
# double( foo * complex(0.d0,-1.d0) ) with foo.imag
qsca += self.compute_qsca(en,an,bn)
gsca += self.compute_gsca(en,an,bn)
if n > 1:
gsca += self.update_gsca(en,an,an1,bn,bn1)
# *** Now calculate scattering intensity pattern
# First do angles from 0 to 90
# LIA : Altered the two loops below so that only the indices where ang
# < 90 are used. Replaced (j) with [indl90]
# Note also: If theta is specified, and np.size(E) > 1,
# the number of E values must match the number of theta
# values. Cosmological halo functions will utilize this
# Diff this way.
pi = pi1
tau = en * amu * pi - (en + 1.0) * pi0
if np.size(indl90) != 0:
antmp = an
bntmp = bn
if nx > 1:
antmp = an[indl90]
bntmp = bn[indl90] # For case where multiple E and theta are specified
s1[indl90] = s1[indl90] + fn* (antmp*pi[indl90]+bntmp*tau[indl90])
s2[indl90] = s2[indl90] + fn* (antmp*tau[indl90]+bntmp*pi[indl90])
#ENDIF
pi_ext = pi1_ext
tau_ext = en*1.0*pi_ext - (en+1.0)*pi0_ext
s1_ext = s1_ext + fn* (an*pi_ext+bn*tau_ext)
s2_ext = s2_ext + fn* (bn*pi_ext+an*tau_ext)
# *** Now do angles greater than 90 using PI and TAU from
# angles less than 90.
# P=1 for N=1,3,...; P=-1 for N=2,4,...
p = -p
# LIA : Previous code used tau(j) from the previous loop. How do I
# get around this?
if np.size(indg90) != 0:
antmp = an
bntmp = bn
if nx > 1:
antmp = an[indg90]
bntmp = bn[indg90] # For case where multiple E and theta are specified
s1[indg90] = s1[indg90] + fn*p* (antmp*pi[indg90]-bntmp*tau[indg90])
s2[indg90] = s2[indg90] + fn*p* (bntmp*pi[indg90]-antmp*tau[indg90])
#ENDIF
s1_back = s1_back + fn*p* (an*pi_ext-bn*tau_ext)
s2_back = s2_back + fn*p* (bn*pi_ext-an*tau_ext)
psi0 = psi1
psi1 = psi
chi0 = chi1
chi1 = chi
xi1 = psi1 - 1j*chi1
# *** Compute pi_n for next value of n
# For each angle J, compute pi_n+1
# from PI = pi_n , PI0 = pi_n-1
pi1 = ( (2.0*en+1.0)*amu*pi- (en+1.0)*pi0 ) / en
pi0 = pi
pi1_ext = ( (2.0*en+1.0)*1.0*pi_ext - (en+1.0)*pi0_ext ) / en
pi0_ext = pi_ext
# ENDFOR
# *** Have summed sufficient terms.
# Now compute QSCA,QEXT,QBACK,and GSCA
gsca = 2.0 * gsca / qsca
qsca = ( 2.0 / np.power(x,2) ) * qsca
# LIA : Changed qext to use s1(theta=0) instead of s1(1). Why did the
# original code use s1(1)?
qext = ( 4.0 / np.power(x,2) ) * s1_ext.real
qback = np.power( np.abs(s1_back)/x, 2) / np.pi
if getQ == 'sca':
return qsca
if getQ == 'ext':
return qext
if getQ == 'back':
return qback
if getQ == 'gsca':
return gsca
if getQ == 'diff':
bad_theta = np.where( theta_rad > np.pi ) #Set to 0 values where theta > !pi
s1[bad_theta] = 0
s2[bad_theta] = 0
return 0.5 * ( np.power( np.abs(s1), 2 ) + np.power( np.abs(s2), 2) ) / (np.pi * x*x)
else:
return 0.0
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
