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arXiv · astro-ph/0509735

Nanodiamond dust and the energy distribution of quasars

L. Binette·A. C. Andersen·H. Mutschke·S. Haro-Corzo
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Abstract

The spectral energy distribution of quasars shows a sharp steepening of the continuum shortward of ~ 1100 A. The steepening could be a result of dust absorption. We present a dust extinction model which considers crystalline carbon grains and compare it with SMC-like dust extinction consisting of a mixture of silicate grains with graphite or amorphous carbon grains. We show that the sharp break seen in individual quasar spectra of intermediate redshif \~ 1-2 can be reproduced by dust absorption provided the extinction curve consists of nanodiamonds, composed of terrestial cubic diamonds or of diamonds similar to the presolar nanodiamonds found in primitive meteorites.

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L. Binette, A. C. Andersen, H. Mutschke, S. Haro-Corzo. 2005-09-24. Nanodiamond dust and the energy distribution of quasars. https://doi.org/10.1002/asna.200510497

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