Astronomy and Astrophysics – Astrophysics
Scientific paper
Oct 1975
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1975apj...201..151s&link_type=abstract
Astrophysical Journal, vol. 201, Oct. 1, 1975, pt. 1, p. 151-164.
Astronomy and Astrophysics
Astrophysics
32
Cosmic Dust, Interstellar Matter, Magnetite, Polarization Characteristics, Absorption Cross Sections, Circular Polarization, Interstellar Gas, Interstellar Magnetic Fields, Light (Visible Radiation), Optical Polarization, Scattering Cross Sections, Stellar Atmospheres
Scientific paper
The polarization and extinction properties of magnetite dust grains are calculated based on indirect evidence that magnetite grains might be the interstellar polarizers. The extinction and phase-lag cross sections of magnetite grains are calculated using a computer method for nonspherical grains. From these, the linear and circular polarization which would be produced by a medium of aligned magnetite dust grains is determined. It is found that flat platelets of magnetite can reproduce the wavelength dependence of the polarization observations. Given the predictions by the Purcell (1974) 'pinwheel' mechanism of perfect alignment for such grains, it is shown that magnetite grains can produce all the observed polarization at visual wavelength by consuming roughly 16 percent of the cosmic abundance of iron atoms in the interstellar medium, while contributing roughly 4 percent of the total visual extinction. With less than perfect alignment, more iron must be put into the magnetite grains, resulting in more magnetite extinction.
No associations
LandOfFree
Interstellar polarization - Magnetite dust 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 Interstellar polarization - Magnetite dust, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interstellar polarization - Magnetite dust will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1743526