Optical Properties of DH16 Amorphous Silicate and Absorption and Scattering Cross Sections

The data provided here are from the paper "Interstellar Amorphous Silicates" (Draine & Hensley 2016, in preparation). Please cite that paper if you use these data.

Dielectric functions

Draine & Hensley (2016, in preparation) present a new estimate for the dielectric tensor of amorphous silicate material, from submm to X-ray energies. The files below present dielectric functions, and cross sections for spherical and spheroidal grains calculated using these dielectric functions.


Cross sections for spheres

Draine & Hensley (2016, in preparation) have calculated cross sections, <cos(theta)>, and <cos^2(theta)> for 41 radii (0.001 micron to 10 micron) and 4001 wavelengths (1.0 cm to 1.0 A) for


Cross sections for spheroids

Draine and Hensley (2016, in preparation) have calculated absorption and scattering cross sections for spheroids, with size a_{eff} [=volume-equivalent radius], using small-spheroid approximations when a_{eff}/lambda is small, and using the spheroid code developed by Voshchinnikov and Farafanov (1993, Astrophys.Sp.Sci. 204, 19) for finite a_{eff}/lambda.

The following files contain cross sections for 169 sizes a_{eff} (0.000316 micron to 5.01um) and 1009 wavelengths (0.0912 micron to 1.0 cm) for oblate spheroids with axial ratio b/a=1.4 . For each size and wavelength, three orientations (jori=1-3) are considered. For a=spheroid symmetry axis, k=direction of propagation, and E = incident electric field:

These are ascii files, each organized as follows: Just to be clear: the Qabs data are in order Qabs(1,0,0),Qabs(2,0,0),Qabs(3,0,0),Qabs(1,1,0),Qabs(2,1,0),...,Qabs(2,168,1008),Qabs(3,168,1008).
and similarly for Qext and Qsca.
Files:

Planck-averaged cross sections for spheres

Draine (2016, in preparation) has calculated Planck-averaged cross sections for absorption and radiation pressure for DH16 amorphous silicate spheres, for sizes from 0.001 micron to 10 micron, and radiation color temperatures from 10K to 5e5 K. [NOT YET AVAILABLE]

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