プランク偏光データに見る分子雲周辺の磁場及び塵粒子の特性: L1689フィラメント
B-field and dust grains around molecular clouds
revealed by Planck polarization data： the L1689
filament
松村雅文 ＆ BISTRO-Jチーム
Masafumi Matsumura & BISTRO-J teamIntroduction (1)• BISTRO: B-fields In Star-forming Region Observations• Use Polarimeter POL-2 in submm region, with SCUBA-2 on JCMT,• To trace the magnetic field in star-forming regions in the Gould Belt.
• PIs: Derek Ward-Thompson (UK); Pierre Bastien (Canada); Ray Furuya (Japan);
Woojin Kwon (Korea); Di Li (China); Shih-Ping Lai (Taiwan) .
• Co-Is: many from Canada, China, EAO, Japan, Korea, Taiwan, & UK

• Regions to study in BISTRO:Auriga, IC5146, Ophiuchus (3 fields), L1689B, Orion A, Orion B, Perseus B1,NGC1333 (2 fields), Serpens (2 fields), Taurus B211/213 (2 fields) , & L1495• Now it is on progress...
→ Furuya-san & Kwon-san’s talks for details.

Introduction (2)• Observation by BISTRO• Sensitive and high-spatial resolution, but not very wide areas.

• This study• investigates the B-field and grains, around the mapping regions by BISTRO,• expects to obtain better understanding of the BISTRO data,• with using available data:• Planck v.202: flux and polarization data
• Low resolution: FWHM=4.9′ @HFI 353GHz (Planck Collaboration, 2016, A&A 594, A8)• But sensitive (3x10-5 KCMB = 2.5 kJy/sr), homogeneous all sky map• optical polarization data. etc.

• This talk considers a filament in L1689 of Oph region.
• This filament contains L1689, L1712, and L1729.

Extinction MapRidge + 2006 AJ 131, 2921

Data used in this study:• Planck data: version 2.02 (released in 2015)• 353GHz all sky map: HFI_SkyMap_353_2048_R2.02_full.fits• CO 3 → 2 line subtraction:• Planck Collaboration, 2014, AA571, A13• “Type 3” method “Multi-line approach”• data: COM_CompMap_CO21-commander_2048_R2.00.fits• CMB subtraction:• data: COM_CMB_IQU-commander-field-Int_2048_R2.01_full.fits• Optical polarimetry:• Vrba et al. 1976, AJ 81, 958 (also Vrba et al. 1993, AJ 105, 1010)• Dust model: “2 component model” ... it uses 2 black (grey) bodies.
• Meisner & Finkbeiner 2015, ApJ 798, 88

τ545

τ545 of 2compmodel
Meisner & Finkbeiner
2015
Av = 8x103 τ545
Regions of L1688
observed by BISTRO arealso indicated.

τ545

τ545 of2comp-model
Meisner &Finkbeiner 2015

Same as theprevious slide, butthe scale is different.

Temperature T2 by 2comp-model

Regions of L1688 observed by BISTRO are also indicated.

Temperature T2 by 2comp-model

Same as the previous slide,but the scale is different.

Polarization• The directions are
the B-field.
• Red: Planck
353GHz submm
polarized flux
• binning:
8.5′×8.5′• Yellow: Opticalpolarization by
Vrba + 1976

Polarization
around L1689(enlarged)• Red: Planck
353GHz submm
polarized flux
• no binning
1.7′×1.7′• Yellow: Opticalpolarization by
Vrba + 1976

Investigated regionof L1689 filament:

From (α0,δ0) =(353.43,16.05)
In the direction ofP.A.=72deg.
Width: ±0.6deg.
Length: ～8 deg.

Fractional Pol.

Position Angle• L1689 filament: (α0,δ0)=(353.43,16.05)
P.A. of cutting: 162d.
162 deg. ≠ 140 deg.
Binning: 8.5′×8.5′

FluxP.A. vs. Vertical direction
Offset < 2.5 deg.
P.A. varies!

P.A. vs. Vertical direction
Offset > 2.5 deg.

Flux vs. Vertical direction
Offset > 2.5 deg.

Flux vs. Vertical direction
Offset < 2.5 deg.

Flux vs. fractional pol in L1689 filament

Offset < 2.5 deg.

Offset > 2.5 deg.

Flux vs. Polarized Flux in L1689 filament

Offset < 2.5 deg.

Offset > 2.5 deg.

Investigated regionof L1688 filament:

From (α0,δ0) =(351.61,17.48)
In the direction ofP.A.=52deg.
Width: ±0.6deg.
Length: ～9 deg.

Fractional Pol.

PositionAngle
Angle
Position• L1688 filament: (α0,δ0)=(351.61,17.48)
P.A. of cutting: 142 deg.
It coincides with P.A.
Binning: 8.5′×8.5′

FluxSummary• L1689–L1712–L1729 filament: warped magnetic field?
• We found that P.A. varies 120 deg. in the NS direction.
• This variation continues along 2.5°(or 5.7 pc in projected linear distance)along the EW direction.
• P.A. is almost constant ～140 deg. in the eastern region.
• But P.A. is NOT exactly the same as the filament direction ～160 deg.

• What is it? Can stellar wind from σ Sco and/or other stars explain it?
• Clumps are present in the L1689 filament.
• In the pol-vector map, those clumps seem not to be affected by the B-field.
• The B-field may be too complicated to resolve, so the appearance of polvectors does not change?

Thank you!

Merci!