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arXiv · 1803.04888

A look at possible microwave dust emission via AKARI infrared all-sky surveys

Aaron C. Bell·Takashi Onaka·Yasuo Doi·Frédéric Galliano·Ronin Wu·Hidehiro Kaneda·Daisuke Ishihara·Martin Giard
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Abstract

The anomalous microwave emission (AME) still lacks a conclusive explanation. This excess of emission, roughly between 10 and 50 GHz, correlates spatially with interstellar dust, prompting a "spinning dust" hypothesis: electric dipole emission by rapidly rotating, small dust grains. The typical peak frequency range of the AME profile implicates grains on the order of ~1 nm, suggesting polycyclic aromatic hydrocarbon molecules (PAHs). We compare AKARI/Infrared Camera (IRC), with its thorough PAH-band coverage, to AME intensity estimates from the Planck Collaboration, in the {\lambda} Orionis region. We look also at infrared dust emission from other mid IR and far-IR bands. The results and discussion contained here apply to an angular scale of approximately 1{\deg}. In general, our results support an AME-from-dust hypothesis. In {\lambda} Orionis, we find that certainly dust mass correlates with AME, and that PAH-related emission in the AKARI/IRC 9 {\mu}m band may correlate slightly more strongly.

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Aaron C. Bell, Takashi Onaka, Yasuo Doi, Frédéric Galliano, Ronin Wu, Hidehiro Kaneda, Daisuke Ishihara, Martin Giard. 2018-03-13. A look at possible microwave dust emission via AKARI infrared all-sky surveys. https://arxiv.org/abs/1803.04888

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