Moping Li et al 2004 ApJ 613 L145 doi:10.1086/425218
Moping Li1, Gang Zhao1 and Aigen Li2,3,4
Show affiliationsThe mineralogical composition of dust contains important information regarding the origin and processing of the dust and the physical, chemical, and evolutionary properties of the astrophysical environment where the dust is found. In the literature, the composition of cosmic dust is usually inferred by fitting the observed infrared (IR) emission spectrum with a sum of emission spectra calculated from various individual grain species of different sizes but assuming a single, identical temperature for them. However, we show in this work that these grains of different compositions and/or different sizes, while in thermal equilibrium with the radiation field to which the grains are exposed, achieve different temperatures. The effects of dust temperature on dust compositional studies are demonstrated by showing that the IR emission spectrum calculated from a mixture of grains emitting at different temperatures differs substantially from that of the same grain mixture but with a single, identical temperature. Therefore, the need for obtaining realistic temperatures from realistic cosmic dust analogs is a key to properly interpreting the observational IR emission spectra, e.g., the rich set of data that the Spitzer Space Telescope has been collecting.
comets: individual (C/2002 V1 (NEAT)); dust, extinction; infrared: ISM; infrared: solar system; radiation mechanisms: thermal
Issue 2 (2004 October 1)
Received 2004 July 18, accepted for publication 2004 August 19
Published 2004 September 1
Moping Li et al 2004 ApJ 613 L145
U. Schwingenschlögl et al 2008 EPL 81 27002
J. T. A. de Jong et al. 2008 ApJ 680 1112
S. Boixo et al 2007 EPL 79 40003
A. Burrows et al. 2006 ApJ 650 1140
M. Giavalisco et al 2004 ApJ 600 L103
Todd C. Hillwig et al. 2000 The Astronomical Journal 120 1113
A. Stoffel and M. Gulácsi 2009 EPL 85 20009
M. M. Kasliwal et al. 2008 ApJ 678 1127
A. Rest et al. 2008 ApJ 680 1137