Mid-infrared spectra of the shocked Murchison CM chondrite: Comparison with astronomical observations of dust in debris disks

Abstract

We present laboratory mid-infrared transmission/absorption spectra obtained from matrix of the hydrated Murchison CM meteorite experimentally shocked at peak pressures of 10 to 49 GPa, and compare them to astronomical observations of circumstellar dust in different stages of the formation of planetary systems. The laboratory spectra of the Murchison samples exhibit characteristic changes in the infrared features. A weakly shocked sample (shocked at 10 GPa) shows almost no changes from the unshocked sample dominated by hydrous silicate (serpentine). Moderately shocked samples (21 to 34 GPa) have typical serpentine features gradually replaced by bands of amorphous material and olivine with increasing shock pressure. A strongly shocked sample (36 GPa) shows major changes due to decomposition of the serpentine and due to devolatilization. A shock melted sample (49 GPa) shows features of olivine recrystallized from melted material. The spectra of highly shocked Murchison samples (36 and 49 GPa) are similar to those of dust in the debris disks of HD113766 and HD69830, and the transitional disk of HD100546. The moderately shocked samples (21 to 34 GPa) exhibit spectra similar to those of dust in the debris disks of Beta Pictoris and BD+20307, and the transitional disk of GM Aur. An average of the spectra of all Murchison samples (0 to 49 GPa) has a similarity to the spectrum of the older protoplanetary disk of SU Auriga. In the gas-rich transitional and protoplanetary disks, the abundances of amorphous silicates and gases have widely been considered to be a primary property. However, our study suggests that impact processing may play a significant role in generating secondary amorphous silicates and gases in those disks. Infrared spectra of the shocked Murchison samples are also suggesting that the comets also contain shocked Murchison-like material.

References in corpus (13)

• A Survey and Analysis of Spitzer Infrared Spectrograph Spectra of T Tauri Stars in Taurus
• Modeling optical properties of cosmic dust grains using a distribution of hollow spheres
• A 10 micron spectroscopic survey of Herbig Ae star disks: grain growth and crystallization
• Spitzer IRS Spectroscopy of IRAS-Discovered Debris Disks
• C2D Spitzer-IRS spectra of disks around T Tauri stars: I. Silicate emission and grain growth
• The origin of crystalline silicates in the Herbig Be star HD100546 and in comet Hale-Bopp
• Crystalline silicates and dust processing in the protoplanetary disks of the Taurus young cluster
• Dust in Resonant Extrasolar Kuiper Belts - Grain Size and Wavelength Dependence of Disk Structure
• On the Nature of the Dust in the Debris Disk Around HD69830
• Circumstellar Dust Created by Terrestrial Planet Formation in HD 113766
• The Dust and Gas Around beta Pictoris
• Temperature effects on the 15-85-micron spectra of olivines and pyroxenes
• Analysis of the dust evolution in the circumstellar disks of TTauri stars

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