Modeling Porous Dust Grains with Ballistic Aggregates. II. Light Scattering Properties

Details Modeling Porous Dust Grains with Ballistic Aggregates. II. Light Scattering Properties Modeling Porous Dust Grains with Ballistic Aggregates. II. Light Scattering Properties

2009-01-15

arxiv.org/abs/0901.2177v1

Astrophys.J.696:2126-2137,2009

Astronomy and Astrophysics

Astrophysics

Earth and Planetary Astrophysics

Submitted to ApJ. Scattering properties can be downloaded at http://www.astro.princeton.edu/~draine/SDJ2009.html Target geomet

Scientific paper

10.1088/0004-637X/696/2/2126

We study the light scattering properties of random ballistic aggregates constructed in Shen et al. (Paper I). Using the discrete-dipole-approximation, we compute the scattering phase function and linear polarization for random aggregates with various sizes and porosities, and with two different compositions: 100% silicate and 50% silicate-50% graphite. We investigate the dependence of light scattering properties on wavelength, cluster size and porosity using these aggregate models. We find that while the shape of the phase function depends mainly on the size parameter of the aggregates, the linear polarization depends on both the size parameter and the porosity of the aggregates, with increasing degree of polarization as the porosity increases. Contrary to previous studies, we argue that monomer size has negligible effects on the light scattering properties of ballistic aggregates, as long as the constituent monomer is smaller than the incident wavelength up to 2*pi*a_0/lambda\sim 1.6 where a_0 is the monomer radius. Previous claims for such monomer size effects are in fact the combined effects of size parameter and porosity. Finally, we present aggregate models that can reproduce the phase function and polarization of scattered light from the AU Mic debris disk and from cometary dust, including the negative polarization observed for comets at scattering angles 160

Affiliated with

Also associated with

No associations

Rating

Modeling Porous Dust Grains with Ballistic Aggregates. II. Light Scattering Properties does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Modeling Porous Dust Grains with Ballistic Aggregates. II. Light Scattering Properties, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modeling Porous Dust Grains with Ballistic Aggregates. II. Light Scattering Properties will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-589625