Nagoya University
Nagoya University
Nagoya University
Nagoya University
Nagoya University
出版者
宇宙航空研究開発機構(JAXA)
出版者（英）
Japan Aerospace Exploration Agency (JAXA)
雑誌名
宇宙航空研究開発機構特別資料
雑誌名(英)
JAXA Special Publication: Proceedings of the SPICA Science Conference from Exoplanets to Distant Galaxies: SPICA's New Window on the Cool Universe
巻
JAXA-SP-17-010E
ページ
121 - 123
発行年
2018-03-09
会議概要（会議名, 開催地, 会期, 主催者等）（英）
SPICA Science Conference from Exoplanets to Distant Galaxies: SPICA's New Window on the Cool Universe (June 18-21, 2013. Ito Hall, the University of Tokyo), Bunkyou-ku, Tokyo, Japan
抄録（英）
A merging process in infrared (IR) galaxies plays an important role in accelerating the processing of dust grains, which may alter the properties of dust grains, e.g. the relative abundance of polycyclic aromatic hydrocarbons (PAHs) to classical grains. In fact, with AKARI, we find that the ratio of the PAH 3.3 μm to IR luminosity, L(sub PAH3.3)/L(sub IR), considerably decreases toward the luminous end of L(sub IR) greater than 10(exp11.5) solar liminosity, using the near-IR (2.5-5 μm) spectra of 100 IR galaxies without AGN signatures. We conclude that local ULIRGs intrinsically possess a smaller amount of PAHs relative to classical grains than less-luminous IR galaxies. Some fraction of PAHs may have been destroyed once by a shock during a merging process, whereas large dust grains survive, which may explain the systematically low abundance ratios of PAHs to classical grains observed for the ULIRGs. To prove this scenario, we should observe a systematic change of the ratio from an interacted region to others, or from outer to inner areas, within a galaxy. With SPICA, especially coronagraphic spectroscopy with the SCI, we can perform a spatially-resolved study of local ULIRGs in both PAH and dust emission, which will reveal the scene of the processing and destruction of dust grains with shocks during merging processes of galaxies.
内容記述
形態: カラー図版あり
内容記述（英）
Physical characteristics: Original contains color illustrations
A Spatially-resolved Study on the Processing and Destruction of Dust Grains in Local ULIRGs
AA1730027027.pdf
(274.61KB)
