The 10 Micron Spectra of Comet C/2002 V1 (NEAT) and C/2001 RX14 (LINEAR)

We have carried out mid-infrared 8–13 � m spectroscopic observations of C/2002 V1 (NEAT) and C/2001 RX14 (LINEAR) on 2003 January 10–11 UT using the Cooled Mid-Infrared Camera and Spectrometer (COMICS) on the 8.2 m Subaru Telescope. The spectra of C/2002 V1 showed the broad silicate feature with the 11.2 � m peak, indicating the presence of crystalline olivine grains. The spectra of C/2001 RX14 also showed the broad trapezoidal silicate feature. The silicate feature profile of C/2002 V1 is explained by a combination of small (0.1 � m) amorphous olivine and pyroxene, large (2.0 � m) amorphous silicate, and small crystalline forsterite grains, while that of C/2001 RX14 is explained by small and large amorphous silicate grains without crystalline silicate grains. The ubiquity of large grains and crystalline silicate grains among these Oort Cloud comets indicates processing of the primordial interstellar matter in the early solar system and incorporation into the region where these cometary nuclei were formed. Subject headings: comets: individual (C/2002 V1, C/2001 RX14) — infrared: solar system

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