THE STAR FORMATIONNEWSLETTER#323 (46-55)
泉奈都子（茨城大学）

46.Meridional flows in the disk around a young star
47.Accretion Kinematics in the T Tauri Binary TWA 3A: Evidence forPreferential Accretion onto the TWA 3A Primary
48.Near-infrared Monitoring of the Accretion Outburst in the MYSO
S255-NIRS3
49.The possible role of stellar mergers for the formation of multiple
stellar populations in globular clusters
50.Predicting the Observational Signature of Migrating Neptune-sized
Planets in Low-viscosity Disks
51.Susceptibility of planetary atmosphere to mass loss and growth byplanetesimal impacts: the impact shoreline
52.Chemical Evolution of HC3N in Dense Molecular Clouds
53.Discovery of a Photoionized Bipolar Outflow towards the Massive
Protostar G45.47+0.05
54.The impact of planet wakes on the location and shape of the water
ice line in a porto-planetary disk
55.Synthetic Large-Scale Galactic Filaments - on their Formation,
Physical Properties, and Resemblance to Observations

46. Meridional flows in the disk around a young star

Richard Teague et al. Accepted by Nature http://arxiv.org/pdf/1910.06980
HD163296の円盤のGap領域において、円盤表面からその中央面に向かうガスの流れ（=子午線流?）を検出• HD163296
d ~ 101 pc- 複数のリング構造が検出 (r ~ 80, 140 pc..)↑~2MJの惑星が埋もれていると考えられている• Observation
ALMA large program: Disk Substructures ad High Angular Resolution Project

ESO,ALMA-(DSHARP)の一環- Line: 12CO(2-1) ←円盤の表面をトレース• Results- Symmetric dipolepatternを検出

↓惑星形成初期段階で起こることが予想されている• Results
Gapのところにcollapsing flow (meridional flow)を検出-‣ vφ: azimuthally averaged rotational velocity‣ vLSR = 5763±1 m/s‣ i = 46.7±0.1°

• Simulation
0.5 M , 1M , 2M の惑星がr=87, 140,237 pcに存在している時のmeridional flow
-JJJ

↑観測結果と一致している53. Discovery of a Photoionized Bipolar Outflow towards theMassive Protostar G45.47+0.05
Lichen Zhang et al. Accepted by ApJL https://arxiv.org/pdf/1910.04271

Massive starにおけるradiation feedbackを調べる• G45.47+0.05
d = 8.4 kpc- Luminosity ~ (2-5) × 105 Lsun
- Mass ~ 20-50 Msun
- Ultracompact HII regionに付随- HCO+(1-0)でoutflow構造が検出• Results
HCO (1-0)のoutflowとconsistent+なwide-angle outflow構造を検出- Center: optically thick ionised gas- Extended structure: optically thinfree-free emission- Jet構造• Observation
ALMA: 1.3 mm continuum, H30α
- VLA: 7mm continuum

model for free-free emissionとの比較• Simple
Isothermal ionised gas がoutflow cavitiesを満たしていることを仮定- Best-fit model: Electron temperature = 104 K, electron number density ~ 1.5 × 107 cm-3
Outer radius of the outflow launching region ~ 110 au- 検出されたOutflowはMHD disk windではなくphotoevaporative outflow（Mass ross rate ~ 3 × 10-5 Msun yr-1）- accretion 起源のjetが検出されていることから、強いphotoevaporative outflowがあってもaccretionは行なわれていることを示している

photo evaporative outflow
をbaseとしたmodel

MHD disk windをbaseとしたmodel

55. Synthetic Large-Scale Galactic Filaments - on their Formation,
Physical Properties, and Resemblance to Observations
Catherine Zucker et al. Accepted by ApJ https://arxiv.org/pdf/1910.11362.pdf

Large-scale Galactic filamentをsimulationによって作成し、その形成過程や性質を調べる• Method
AREPO simulations (smith et al., 2014)-‣ Four-armed spiral potential‣ self-gravity, stellar-feedbackは含まない‣ CO, H2のsimpleなchemical modelは含む

• Results
armとinterarm領域において形成されるfilamentの性質が異なる-‣ arm内部のfilament: gas compression in the spiral-potential wellsによって形成‣ interarmのfilament: differential rotationによって形成• Results
実際に観測されているfilamentとの比較-‣ “Giant Molecular Filaments” は今回の単純なsimulationによって作成可能→ 銀河のダイナミクスのみで形成される‣ “Bone-like filament”は今回のsimulationでは作成不可能→ local-self gravityや stellar feedbackが必要47. Accretion Kinematics in the T Tauri Binary TWA 3A: Evidence
for Preferential Accretion onto the HWA 3A Primary
Benjamin M. Tofflemire et al. Accepted by AJ https://arxiv.org/pdf/1910.12878

48. Near-infrared Monitoring of the Accretion Outburst in theMYSO S255-NIRS3
Mizuho Uchiyama et al. Accepted by PASJ

https://arxiv.org/pdf/1910.07691

49. The possible role of stellar mergers for the formation ofmultiple stellar populations in globular clusters
Long Wang et al. Accepted by MNRAS https://arxiv.org/pdf/1910.14040

50. Predicting the Observational Signature of Migrating Neptunesized Planets in Low-viscosity Disks
Philipp Weber et al. Accepted by ApJ https://arxiv.org/pdf/1909.01661.pdf

51. Susceptibility of planetary atmospheres to mass loss andgrowth by planetesimal impacts: the impact shoreline
M. C. Wyatt et al. Accepted by MNRAS https://arxiv.org/pdf/1910.10731

52. Chemical Evolution of HC3N in Dense Molecular Clouds
Napping Yu et al. Accepted by MNRAS http://arxiv.org/pdf/1910.07222

54. The impact of planet wakes on the location and shape of thewater ice line in a protoplanetary disk
Alexandros et al. Accepted by A&A http://arxiv.org/pdf/1910.08560