Hiroshi Kimura

Graduate School of Science, Kobe University, c/o CPS (Center for Planetary Science), Chuo-ku Minatojima Minamimachi
7-1-48, Kobe 650-0047, Japan

We model dust in comets, protoplanetary disks, and debris disks as aggregates consisting of submicron-sized grains with a silicate core and an organic-rich carbonaceous mantle. By computing the infrared (IR) spectra of the aggregates, we show that the degree of carbonization determines the positions of infrared peaks characteristic of magnesium-rich crystalline silicates. We discuss our results in terms of processing of organic materials by ultraviolet irradiation, ion bombardments, and thermal devolatilization. A comparison between the model IR spectra of the aggregates and the observed spectra of dust in circumstellar disks reveals that at least one third of the organic refractory component has suffered from carbonization in a very short timescale.

Reference
Kimura H (in press) The Organic-Rich Carbonaceous Component of Dust Aggregates in Circumstellar Disks: Effects of Its Carbonization on Infrared Spectral Features of Its Magnesium-Rich Olivine Counterpart. Icarus
[doi:10.1016/j.icarus.2014.01.009]
Copyright Elsevier

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Romain Tartèse^a and Mahesh Anand^b

^aPlanetary and Space Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, United Kingdom
^bDepartment of Earth Sciences, The Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom

Referes to
Romain Tartèse, Mahesh Anand
Late delivery of chondritic hydrogen into the lunar mantle: Insights from mare basalts
Earth and Planetary Science Letters, Volume 361, 1 January 2013, Pages 480-486

The authors regret for an error which was introduced in an intermediate step involved in calculating the amount of chondritic material added to the lunar interior to account for the estimated H content of the mare basalt source regions (Section 6, lines 12–25). The revised text is as follows:
Assuming a 400 km deep solidified mantle with 25 ppm H and a density of 3300 kg m⁻³ implies that∼1×10¹⁸ kg of H has been added by chondrite-type impactors and efficiently mixed in the upper lunar mantle. Taking the measured H content of ∼5000–15 000 ppm in CI chondrites (Alexander et al., 2012 and Kerridge, 1985), this represents a mass of about 6.2×10¹⁹ to 1.8×10²⁰ kg of CI-type material accreted to the lunar upper mantle. This corresponds to 0.2–0.5 wt.% of the 400 km deep upper mantle considered here. By comparison, HSE abundances in lunar basalts require an amount of ∼1.6×10¹⁹ kgof chondritic material to have been accreted and mixed into the lunar upper mantle (Bottke et al., 2010 and Day et al., 2007), around 8±4 times less than that required for a lunar mantle with 25 ppm H.

Reference
Tartèse R and Anand M (in press) Corrigendum to “Late delivery of chondritic hydrogen into the lunar mantle: Insights from mare basalts” [Earth Planet. Sci. Lett. 361 (2013) 480–486]. Earth and Planetary Science Letters
[doi:10.1016/j.epsl.2014.01.002]
Copyright Elsevier

Link to Article