Exemplo n.º 1
0
    def luminosity_correction(self):
        """
        The FSPS templates are in L_sun/Angstrom, with L_sun = 3.83e26W
          so we change to the appropriate flux at each relevent redshift.

        Our SED code gives correct magnitudes if the SED is in units of
          ergs/s/cm/cm/Angstrom, and our distance class gives distances in
          Mpc/h, so we will need to use the conversion Mpc = 3.08568e24cm
          and assume a value for h.

        The conversion factor is conv = flux_density/luminosity_density and
          the templates should therefore be multiplied by conv to get the
          correct flux_density. The factor of (1+z) accounts for the fact that
          these are _densities_.

                        3.83e33
            conv =  ----------------
                    (1+z) 4 pi Dl**2
        """
        import distances
        from math import pi
        z = self.redshift
        dist = distances.Distance()
        cm_per_Mpc = 3.08568e24
        if z == 0:
            dl = 1e-5 * cm_per_Mpc
        else:
            dl = dist.Dl(z) * cm_per_Mpc
        conv = 1. / (4 * pi * dl**2)
        conv *= 3.83e33
        return conv
Exemplo n.º 2
0
    def __init__(self,
                 D=None,
                 reset=False,
                 zlmax=2,
                 sigfloor=100,
                 bands=[
                     'F814W_ACS', 'g_SDSS', 'r_SDSS', 'i_SDSS', 'z_SDSS',
                     'Y_UKIRT'
                 ],
                 cosmo=[0.3, 0.7, 0.7],
                 sourcepop="lsst"):
        self.sourcepopulation = sourcepop
        if D == None:
            import distances
            D = distances.Distance(cosmo=cosmo)

        self.L = LensPopulation(reset=reset,
                                sigfloor=sigfloor,
                                zlmax=zlmax,
                                bands=bands,
                                D=D)

        self.S = SourcePopulation(reset=reset,
                                  bands=bands,
                                  D=D,
                                  population=sourcepop)

        self.E = EinsteinRadiusTools(D=D)
Exemplo n.º 3
0
    def loglkl(self, cosmo, data):
        lkl = 0
        lensing_da_lognorm = np.zeros((self.num_points), 'float64')
        if cosmo.Omega_fld() and -1.e-3 < cosmo.Omega_lambda() < 1.e-3:
            params = [
                cosmo.Omega_m(),
                cosmo.Omega_fld(),
                cosmo.h(),
                cosmo.w0(),
                cosmo.wa()
            ]
        else:
            params = [
                cosmo.Omega_m(),
                cosmo.Omega_lambda(),
                cosmo.h(), -1., 0.
            ]
            #params = [self.cosmo_arguments['Omega_m'],self.cosmo_arguments['Omega_fld'],self.cosmo_arguments['h'],-1.,0.]
        import distances
        D = distances.Distance(params)

        for i in range(self.num_points):
            lensing_da_lognorm[i] = D.angular_diameter_distance(self.zl[i])
            chi2 = np.log(lensing_da_lognorm[i] - self.loc[i]) + (
                (np.log(lensing_da_lognorm[i] - self.loc[i]) -
                 np.log(self.scale[i])) / self.shape[i])**2. / 2.
            # return ln(L)
            lkl -= chi2

        return lkl
Exemplo n.º 4
0
    def __init__(self,zl,zs,nplanes=100,cosmo=[0.25,0.75,0.73]): 

        assert zs > zl
        
        D = distances.Distance()
        self.name = '1D Redshift grid of lens planes, each containing precalculated quantities '
        self.zmax = zs*1.0
        self.zs = zs*1.0
        self.zltrue = zl
        self.nplanes = nplanes
        self.cosmo = cosmo
        
        # These are the plane redshifts:
        self.redshifts,self.dz = self.redshiftbins = numpy.linspace(0.0,self.zmax,self.nplanes,endpoint=True,retstep=True)
        self.redshifts += (self.dz/2.)
        self.nz = len(self.redshifts)
        
        # Snap lens to grid, and compute special distances:
        self.zl = self.snap([zl])[0][0]
        self.Da_l = D.Da(zl)
        self.Da_s = D.Da(zs)
        self.Da_ls = D.Da(zl,zs)
        self.plane = {}

        # Grid planes:
        self.Da_p = numpy.zeros(self.nz)
        self.rho_crit = numpy.zeros(self.nz)
        self.Da_ps = numpy.zeros(self.nz)
        self.Da_pl = numpy.zeros(self.nz)
        self.sigma_crit = numpy.zeros(self.nz)
        self.beta = numpy.zeros(self.nz)
        for i in range(self.nz):
            z = self.redshifts[i]
            self.Da_p[i] = D.Da(0,z)
            self.rho_crit[i] = D.rho_crit_univ(z)
            self.Da_ps[i] = D.Da(z,zs)
            self.Da_pl[i] = D.Da(z,zl)
            self.sigma_crit[i] = (1.663*10**18)*(self.Da_s/(self.Da_p[i]*self.Da_ps[i]))  # units M_sun/Mpc^2
            if z > zl: # 1 is lens, 2 is perturber
                D1s = self.Da_ls
                D2  = self.Da_p[i]
            else:      # 1 is perturber, 2 is lens
                D1s = self.Da_ps[i]
                D2  = self.Da_l
            D12 = self.Da_pl[i]
            self.beta[i] = (D12*self.Da_s)/(D2*D1s)

        return
Exemplo n.º 5
0
    def beginRedshiftDependentRelation(self,
                                       D,
                                       reset,
                                       zmax=10,
                                       cosmo=[0.3, 0.7, 0.7]):
        self.zmax = zmax
        self.zbins, self.dz = numpy.linspace(0, self.zmax, 401, retstep=True)
        self.z2bins, self.dz2 = numpy.linspace(0, self.zmax, 201, retstep=True)
        if D == None:
            D = distances.Distance(cosmo=cosmo)
        self.D = D

        if reset != True:
            try:
                #load useful redshift splines
                splinedump = open("redshiftsplines.pkl", "rb")
                self.Da_spline, self.Dmod_spline, self.volume_spline, self.Da_bispline = cPickle.load(
                    splinedump)
            except IOError or EOFError:
                self.redshiftfunctions()
        else:
            self.redshiftfunctions()
Exemplo n.º 6
0
import distances
import lenspop

# Simulate all lenses on the sky - takes about 7 hours:
# fsky = 1
# Fast test - under a minute:
fsky = 0.001

D = distances.Distance()

Lpop = lenspop.LensPopulation(reset=True, sigfloor=100, zlmax=2, D=D)

Ndeflectors = Lpop.Ndeflectors(2, zmin=0, fsky=fsky)

L = lenspop.LensSample(reset=False, sigfloor=100, cosmo=[0.3,0.7,0.7],
               sourcepop="lsst")

L.Generate_Lens_Pop(int(Ndeflectors), firstod=1, nsources=1, prunenonlenses=True)