Japan Geoscience Union Meeting 2022

Presentation information

[J] Oral

P (Space and Planetary Sciences ) » P-CG Complex & General

[P-CG20] Origin and evolution of materials in space

Fri. May 27, 2022 3:30 PM - 5:00 PM 302 (International Conference Hall, Makuhari Messe)

convener:Takafumi Ootsubo(National Astronomical Observatory of Japan, National Institutes of Natural Sciences ), convener:Hideko Nomura(Division of Science, National Astronomical Observatory of Japan), Aki Takigawa(Department of Earth and Planetary Science, The University of Tokyo), convener:Sota ARAKAWA(National Astronomical Observatory of Japan), Chairperson:Shota Notsu(Star and Planet Formation Laboratory, RIKEN Cluster for Pioneering Research), Kenji Furuya(National Astronomical Observatory of Japan)


4:45 PM - 5:00 PM

[PCG20-12] Laboratory experiment analogous to interstellar carbon dust and its infrared spectrum analysis

*Norio Ota1, Aigen Li2, Laszlo Nemes3, Masaaki Otsuka4 (1.University of Tsukuba,Graduate school of pure and applied sciences, 2.University of Missouri, 3.Academy of Science, Hungary, 4.Kyoto University)

Keywords:interstellar dust, carbon, infrare spectrum

Soccer ball like carbon molecule-fullerene C60 is well studied as a candidate of interstellar carbon dust. Also, it is well known that fullerene could be synthesized by plane graphene molecules. This study tried the analogous laboratory experiment to find specified carbon molecules in space. On the occurrence of star explosion, high energy light seriously illuminates and modify carbon dust. In our experiment, Nd:YAG laser illuminated bulk graphite. Ablated carbon cluster was analyzed by the infrared spectrometer as resulted in figure (A). Infrared spectra (IR) of candidate molecules are compared by the quantum-chemical calculation. Among them, graphene C23 having one carbon pentagon combined with six hexagons shows the resemblance with laboratory experiment as illustrated in (B). Graphene with a void defect would be thermally pealed from bulk graphite. Astronomical spectra obtained in planetary nebulae Tc1 and Lin49 are shown in the figure (C), which result very good coincidence with calculated IR of C23, also rough coincidence with the laboratory experiment. Also, it should be noted that well observed bands at 18.9 and 17.4 micrometer in many planetary nebulae are well reproduced by C23. This study pointed out that graphene is an important component of carbon dust.