211 research outputs found
Experimental study of lateral diffusion on the bilayer membrane(Poster session 2, New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter)
この論文は国立情報学研究所の電子図書館事業により電子化されました。2分子膜ベシクルの構成成分が相分離して形成されたマイクロドメインは、液体膜の性質を持つベシクルの球面に沿ってブラウン運動する。過去の幾つかの研究と同様に、通常の相分離と同じくドメインが融合合体成長して最終的に大きく二相分離するベシクルと、ベシクル上の相分離ドメインが小さなドメインのままで長時間維持されるベシクルの、2種類が観察された。本実験では、クエンチからの時間をさほど考慮しなくても良いと思われる、マイクロドメインが安定に分散された状態のベシクルを対象として観察を行った。このときの画像を取得する事でドメインの拡散係数を求めると共に、ドメイン間の距離を測定する事で実効的なドメイン間相互作用を直接求めた
Infrared 3-4 Micron Spectroscopy of Nearby PG QSOs and AGN-Nuclear Starburst Connections in High-luminosity AGN Populations
We present the results of infrared L-band (3-4 micron) slit spectroscopy of
30 PG QSOs at z < 0.17, the representative sample of local high-luminosity,
optically selected AGNs. The 3.3 micron polycyclic aromatic hydrocarbon (PAH)
emission feature is used to probe nuclear (< a few kpc) starburst activity and
to investigate the connections between AGNs and nuclear starbursts in PG QSOs.
The 3.3 micron PAH emission is detected in the individual spectra of 5/30 of
the observed PG QSOs. We construct a composite spectrum of PAH-undetected PG
QSOs and discern the presence of the 3.3 micron PAH emission therein. We
estimate the nuclear-starburst and AGN luminosities from the observed 3.3
micron PAH emission and 3.35 micron continuum luminosities, respectively, and
find that the nuclear-starburst-to-AGN luminosity ratios in PG QSOs are similar
to those of previously studied AGN populations with lower luminosities,
suggesting that AGN-nuclear starburst connections are valid over the wide
luminosity range of AGNs in the local universe. The observed
nuclear-starburst-to-AGN luminosity ratios in PG QSOs with available
supermassive black hole masses are comparable to a theoretical prediction based
on the assumption that the growth of a supermassive black hole is controlled by
starburst-induced turbulence.Comment: 10 pages, 5 figures, accepted for publication in PASJ (No. 63, 2011
March, Subaru special issue
AKARI IRC 2.5-5 um Spectroscopy of Infrared Galaxies over a Wide Luminosity Range
We present the result of a systematic infrared 2.5-5 um spectroscopic study
of 22 nearby infrared galaxies over a wide infrared luminosity range (10 <
log(L_IR / Lsun) < 13) obtained from AKARI Infrared Camera (IRC). The unique
band of the AKARI IRC spectroscopy enables us to access both the 3.3 um
polycyclic aromatic hydrocarbon (PAH) emission feature from star forming
activity and the continuum of torus-dust emission heated by an active galactic
nucleus (AGN). Applying our AGN diagnostics to the AKARI spectra, we discover
14 buried AGNs. The large fraction of buried AGNs suggests that AGN activity
behind the dust is almost ubiquitous in ultra-/luminous infrared galaxies
(U/LIRGs). We also find that both the fraction and energy contribution of
buried AGNs increase with infrared luminosity from 10 < log(L_IR / Lsun) < 13,
including normal infrared galaxies with log (L_IR / Lsun) < 11. The energy
contribution from AGNs in the total infrared luminosity is only ~7% in LIRGs
and ~20% in ULIRGs, suggesting that the majority of the infrared luminosity
originates from starburst activity. Using the PAH emission, we investigate the
luminosity relation between star formation and AGN. We find that these infrared
galaxies exhibit higher star formation rates than optically selected Seyfert
galaxies with the same AGN luminosities, implying that infrared galaxies could
be an early evolutionary phase of AGN.Comment: 13 pages, 8 figures, accepted for publication in Ap
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