あかり遠赤外線全天サーベイによる銀河ダスト構造の解明

土井靖生 (東京大学)FIS diffuse map making team

FIS Map Making Team

Yasuo DoiShinya Komugi

Norio IkedaTakafumi OotsuboMasahiro Tanaka

Mitsunobu KawadaShuji Matsuura

Yoshimi KitamuraTakao Nakagawa

Makoto HattoriLys Figueredo

Mireya Etxaluze AzkonagaGlenn White

AKARI satellite

Continuous All-Sky Survey Mapping● Sun synchronous polar orbit – just like IRAS● 900 km orbital altitude / 98 min orbital period

Band center [um] 65 90 140 16074x56 93x64 107x85 94x78

12 2 4 7PSF size [arcsec]Detection limit [1σ, MJy/sr]

AKARIAKARI 90um+140um Cygnus

Far-infrared all sky mappingFar-infrared all sky mapping

Note that the numbers are preliminary.

Survey coverage

all sky map in ecliptic coordinates

blue: 1black: 0 light blue: 2 green: 3～ red: 10～

Survey coverage

● >99% of the sky has been covered, >97-98% of them are multiply scanned

● Scan coverage is not spatially uniform● stripy non-observed regions around the ecliptic plane● Data quality depends upon Nscan (under investigation)

● Better coverage is expected with careful investigation/recovery of the data around Moon

Higher spatial resolution than IRAS, comparable to Spitzer

FIS 90μm FIS 140μm MIPS 160μmHPBW 38”

Herschel 160μmHPBW 12”

AKARI covers the whole sky with ~1’ resolution

AKARI/SW wide AKARI/LW wide

Characteristics of the AKARI FIR survey Extended wavelength coverage beyond 100 mμ

BGs' color temperature, SED investigation

Unprecedented spatial dynamic range of >104

From arcminute-scale to the whole sky

AKARI

N60

WideS

WideL

N160

All sky images Shorter wavebands ISRF intensity∝ Longer wavebands ISRF intensity × dust column∝

Cygnus X (20°×15°, 65, 90, 140μm)

AKARIIRISDIRBE

CygnusX SED

Model by DustEM (Compiegne 2011)

Multiple component along LoS?

Galliano et al. 2011

Polaris Flare (15°×15°)

WideS(90μm) WideL(140μm)0~60 MJy/sr0~20 MJy/sr

Spatial power spectraStructure down to ~2'(WideL) & ~1'(WideS) can be successfully traced

Miville-Deschenes (2010)

∝k^-2.65±0.1

SPIRE250μm in central Polaris Flare

Spatial power spectraStructure down to ~2'(WideL) & ~1'(WideS) can be successfully traced

Miville-Deschenes (2010)

∝k^-2.65±0.1

SPIRE250μm in central Polaris Flare

銀河系内星間物質の成分分離

● Planck による飛躍的進展

● ダストピークの観測が重要● DIRBE(42' beam) → AKARI(1'-2' beam)！！

● Herschel/Hi-GAL● 70, 170, 250, 350, 500μm● 銀緯±1°以内

● 100μm前後のデータが欠損→AKARI 90μmの重要性

● 高空間分解能を活かし、よりローカルな星間環境の分離へ● 誰かやりませんか？？

Cosmic Web??

WideS(90μm) WideL(140μm)0~60 MJy/sr0~20 MJy/sr

Polaris Flare (15°×15°)

Interstellar filaments

Andre et al. 2010

Hill et al. 2011

Interstellar filaments● As a site of star-formation● Typical width: ~0.1 pc

⇔ 3.4 arcmin @ 100pc, 1.1 arcmin @ 300pc● AKARI provides a complete map of the local

interstellar filaments

Arzoumanian et al. 2011

Hill et al. 2011

Interstellar filaments● Typical width: ~0.1 pc

⇔ 3.4 arcmin @ 100pc, 1.1 arcmin @ 300pc● AKARI provides a complete map of the local

interstellar filaments

Interstellar filaments● Typical width: ~0.1 pc

⇔ 3.4 arcmin @ 100pc, 1.1 arcmin @ 300pc● AKARI provides a complete map of the local

interstellar filaments!! → 誰かやりませんか？？

近日公開予定

．．．ご利用下さいm(_ _)m