14: A high pitch angle structure in the Sagittarius Arm
M. A. Kuhn (1), R. A. Benjamin (2), C. Zucker (3), A. Krone-Martins (4,5), R. S. de Souza (6), A. CastroGinard (7), E. E. O. Ishida (8,9), M. S. Povich (10), L. A. Hillenbrand (1),Context: In spiral galaxies, star formation tends to trace features of the spiral pattern, including arms, spurs,feathers, and branches. However, in our own Milky Way, it has been challenging to connect individual starforming regions to their larger Galactic environment owing to our perspective from within the disk. One
feature in nearly all modern models of the Milky Way is the Sagittarius Arm, located inward of the Sun witha pitch angle of ~12 deg.
Aims: We map the 3D locations and velocities of star-forming regions in a segment of the Sagittarius Arm
using young stellar objects (YSOs) from the Spitzer/IRAC Candidate YSO (SPICY) catalog to compare theirdistribution to models of the arm.
Methods: Distances and velocities for these objects are derived from Gaia EDR3 astrometry and molecularline surveys. We infer parallaxes and proper motions for spatially clustered groups of YSOs and estimate
their radial velocities from the velocities of spatially associated molecular clouds.
Results: We identify 25 star-forming regions in the Galactic longitude range l~4.0-18.5 deg arranged in anarrow, ~1 kpc long linear structure with a high pitch angle of ψ=56 deg and a high aspect ratio of ~7:1.
This structure includes massive star-forming regions such as M8, M16, M17, and M20. The motions in the
structure are remarkably coherent, with velocities in the direction of Galactic rotation of |Vf|=240±3 km/s
(slightly higher than average) and slight drifts toward the Galactic center (-4.3 km/s) and in the negative Z
direction (Vz~-2.9 km/s). The rotational shear experienced by the structure is DW=4.6 km/s/kpc.
Conclusions: The observed 56 deg pitch angle is remarkably high for a segment of the Sagittarius Arm. We
discuss possible interpretations of this feature as a substructure within the lower pitch angle Sagittarius
Arm, as a spur, or as an isolated structure.

spiral arm の中にspurs (luminous stellar features),feathers (dust features), branchesStar Formation
Handbook天体

1次元構造
⻑さ950pc
軸⽐＝14:2:1
ピッチ⾓=56°
システマテックな構造
射⼿座腕より⼤

射⼿座腕Sagittariu
Local

S24µm ⇠ 5 ⇥ 1040 erg s 1 kpc 2<latexit sha1_base64="la5ATrNI8tVG8oPfZvnyYxJdkPY=">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</latexit>

予想HII knotsとして
中間クラス

extinction

固有運動

Gaia位置天⽂

cf.Zucker+2020

pc
1k|V | ⇠ 240 ± 3km s 1<latexit sha1_base64="rVPvVPGFiezMkl9fJbQRDuOwBfc=">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</latexit>

8<latexit sha1_base64="z4D/rz3Mr4LuEAC+bjfaQZS0p0Y=">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</latexit>|VR | =

GC

<latexit sha1_base64="2sxqLTjm93/fK2XrJfC9n75yIM8=">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</latexit>|Vz | =

pitch angle
=56度
⼤局的な腕

★☆YSO,●maser

4.3 ± 3.5km s 1

2.9km s 1

shear = 4.6 km s 1 kpc<latexit sha1_base64="wK+2id4BFRCn1bEUfhyhs3y2lps=">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</latexit>

τsh~90Myr
銀経Wada,Koda2004

Kim,Ostriker 2002

La Vigne, Vogel, Ostriker 2006
成因？重⼒、速度シア、銀河衝撃波、MHD

15: The density structure of supersonic self-gravitating turbulence
Shivan Khullar, Christoph Federrath, Mark R. Krumholz, Christopher D. Matzner
We conduct numerical experiments to determine the density probability distribution function (PDF)
produced in supersonic, isothermal, self-gravitating turbulence of the sort that is ubiquitous in star-forming
molecular clouds. Our experiments cover a wide range of turbulent Mach number and virial parameter,
allowing us for the first time to determine how the PDF responds as these parameters vary, and we
introduce a new diagnostic, the dimensionless star formation efficiency versus density (ϵff(s)) curve, which
provides a sensitive diagnostic of the PDF shape and dynamics. We show that the PDF follows a universal
functional form consisting of a log-normal at low density with two distinct power law tails at higher density;
the first of these represents the onset of self-gravitation, and the second reflects the onset of rotational
support. Once the star formation efficiency reaches a few percent, the PDF becomes statistically steady,with no evidence for secular time-evolution at star formation efficiencies from about five to 20 percent. We
show that both the Mach number and the virial parameter influence the characteristic densities at which
the log-normal gives way to the first power-law, and the first to the second, and we extend (for the former)
and develop (for the latter) simple theoretical models for the relationship between these density thresholds
and the global properties of the turbulent medium.
FLASH
基礎⽅程式
磁場なし、等温、3次元の駆動乱流、
V
s

M=
/c 2
5 VL
↵vir,0 =6GMc<latexit sha1_base64="7Ejx9cKAT77+FFy6Si5L8XQyC3c=">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</latexit><latexit sha1_base64="lDNruDstG1B2kMpOQESfn7TuvT0=">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</latexit>

density PDF (probability distributionfunction)(1) 対数正規分布(2) 指数分布1(3) 指数分布2solenoidal+compressibleのnatural mixture FederrahL2010

LN+PN

正規分布
対数分布

s = log ⇢<latexit sha1_base64="2uIawY7thhV/kroNBS6Yc5pUlm8=">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</latexit>

独⽴パラメータ2個 ↵g ,<latexit sha1_base64="YU3JuYM0blhzWUqQMDa1MXuSUdQ=">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</latexit>s

LN+2PNs<latexit sha1_base64="GvvPHEK+j5bh939ee9/3ta6b7g4=">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</latexit>

独⽴パラメータ4個 ↵g ,<latexit sha1_base64="w3+vMcTXUg4EnzBVqw4zh1hrNsY=">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</latexit>s , ↵d , sd

Star Formation Efficiency

SFR
✏↵ =
Mgas /t↵<latexit sha1_base64="hbxdsCtZaBBmMqd+U8HXhbWGvxI=">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</latexit>

s以上の密度のガスの全質量s以上の密度の平均
⾃由落下時間SFR✏↵ (s) =Mgas (s)/t↵ (s)<latexit sha1_base64="d59g69hM1c2WkyikO0btDZrlvGg=">AAACtHichVFNTxQxGH4YlI9F2VUvJF4IGwxe1q4hYExIiCTEixF2WSBhyKZTO0vDfGXa3QQn8wf8Ax48QWKM8ewv8OIf8EC84sFwhMSLB9+ZHTBCwLdp+/Tp+7x92jqRp7Rh7HDAGrxxc2h4ZLQ0duv2eLly5+66DruxkC0RemG86XAtPRXIllHGk5tRLLnveHLD2V3K9jd6MtYqDNbMXiS3fd4JlKsEN0S1Ky9tGWnlEbR9bnZiP3HddEY/XLDdmIvkjGwuN9I0eXGe1OE6y3pkLsjSdqXKaiyPycugXoAqilgJKx9g4xVCCHThQyKAIeyBQ1PbQh0MEXHbSIiLCal8XyJFibRdypKUwYndpbFDq62CDWid1dS5WtApHvWYlJOYZt/YR3bCvrJP7Cf7fWWtJK+Redmj2elrZdQuv5lo/vqvyqfZYOev6lrPBi6e5F4VeY9yJruF6Ot7r9+eNJ82ppMH7IAdk/99dsi+0A2C3ql4vyob71CiD6hffO7LYP1xrT5Xm12drS4+K75iBPcxhRl673ks4jlW0KJzP+M7jvDDmrNsS1iyn2oNFJp7+Ces4A/Cc6rN</latexit>=

↵vir,0 = 1<latexit sha1_base64="YoGjqfuDjsjRgEaklkHe5+ZhdO8=">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</latexit>

M=5<latexit sha1_base64="kAqh+fPicPYxB0hlCywH7oyYNTg=">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</latexit>

mass weighted density<latexit sha1_base64="+Hqh9HgZecj2rkbrOyjMWNfz9vs=">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</latexit>↵g = 3/2

SFE = 0<latexit sha1_base64="ZrYGgmV4m7KQiDpl+nkY2FnTXfE=">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</latexit><latexit sha1_base64="c81C2H78eRWEMGVuE+kHKa70KSs=">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</latexit>↵d > 3/2

R 2⇢ dx⇢mwd ⌘ R⇢dx<latexit sha1_base64="C5iKbe8xTAX55SjCpBoh8DEfwSE=">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</latexit>

not bound☆ぬき1) bound system @sg2) rotation supportscale<latexit sha1_base64="QDlWZwGhO7LcxBX7YCgKl3a+suM=">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</latexit>

SFE = 5%

☆こみ
bound

16: The Transition of Polarized Dust Thermal Emission from the Protostellar Envelope to the Disk
Scale
Ka Ho Lam (1), Che-Yu Chen (1 and 2), Zhi-Yun Li (1), Haifeng Yang (3), Erin G. Cox (4), Leslie W.
Looney (5), Ian Stephens (6 and 7)
Polarized dust continuum emission has been observed with ALMA in an increasing number of deeply
embedded protostellar systems. It generally shows a sharp transition going from the protostellar envelope
to the disk scale, with the polarization fraction typically dropping from ~5% to ~1% and the inferredmagnetic field orientations becoming more aligned with the major axis of the system. We quantitatively
investigate these observational trends using a sample of protostars in the Perseus molecular cloud andcompare these features with a non-ideal MHD disk formation simulation. We find that the gas density
increases faster than the magnetic field strength in the transition from the envelope to the disk scale,
which makes it more difficult to magnetically align the grains on the disk scale. Specifically, to produce theobserved ~1% polarization at ~100au scale via grains aligned with the B-field, even relatively small grainsof 1μm in size need to have their magnetic susceptibilities significantly enhanced (by a factor of ~20) overthe standard value, potentially through superparamagnetic inclusions. This requirement is more stringent
for larger grains, with the enhancement factor increasing linearly with the grain size, reaching ~2×104 formillimeter-sized grains. Even if the required enhancement can be achieved, the resulting inferred magnetic
field orientation in the simulation does not show a preference for the major axis, which is inconsistent withthe observed pattern. We thus conclude that the observed trends are best described by the model where
the polarization on the envelope scale is dominated by magnetically aligned grains and that on the disk
scale by scattering.

<latexit sha1_base64="iC7WHVNcawCWm7clA3zVdbhbAbY=">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</latexit>

磁気分極

M = ⌦/

磁場整列の条件

χ: magnetic susceptibility<x

磁気モーメント: |M| 4pa3/3 = |M|V
磁気トルク=|M|VB<latexit sha1_base64="ExE81/IiZagzpNmPSjBHtaykXdI=">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</latexit>

ラーマー歳差時間：

ˆ⇠1

a<1μm サブミクロンダスト

ダストのパラメータ

常磁性体<latexit sha1_base64="ExE81/IiZagzpNmPSjBHtaykXdI=">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</latexit>

ˆ⇠1

ガスダンピング時間<latexit sha1_base64="UlhjUhzCMsJwpvpftaTFvwHYEmQ=">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</latexit>tL < td<latexit sha1_base64="UmaP8TUsxl3Nyr0wVd0h5T51sa4=">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</latexit>

磁場に整列が起こるには< ⇠ の部分だけ以下を積分
成り⽴たな
い部分に、
短軸⽅向1%の散乱偏光

17: The link between gas and stars in the S254-S258 star-forming region
D. A. Ladeyschikov, M. S. Kirsanova, A. M. Sobolev, M. Thomasson, V. Ossenkopf-Okada, M. Juvela, S. A.
Khaibrakhmanov, E. A. Popova
The paper aims to study relation between the distributions of the young stellar objects (YSOs) of different
ages and the gas-dust constituents of the S254-S258 star-formation complex. This is necessary to study
the time evolution of the YSO distribution with respect to the gas and dust compounds which areresponsible for the birth of the young stars. For this purpose we use correlation analysis between
different gas, dust and YSOs tracers. We compared the large-scale CO, HCO+, near-IR extinction, and farIR Herschel maps with the density of YSOs of the different evolutionary Classes. The direct correlation
analysis between these maps was used together with the wavelet-based spatial correlation analysis. This
analysis reveals a much tighter correlation of the gas-dust tracers with the distribution of Class I YSOs
than with that of Class II YSOs. We argue that Class I YSOs which were initially born in the central brightcluster S255-IR (both N and S parts) during their evolution to Class II stage (~2 Myr) had enough time totravel through the whole S254-S258 star-formation region. Given that the region contains several isolated
YSO clusters, the evolutionary link between these clusters and the bright central S255-IR (N and S)
cluster can be considered. Despite the complexity of the YSO cluster formation in the non-uniform
medium, the clusters of Class II YSOs in the S254-258 star-formation region can contain objects born inthe different locations of the complex.

18. SiO Outflows as Tracers of Massive Star Formation in Infrared Dark Clouds
Mengyao Liu, Jonathan C. Tan, Joshua Marvil, Shuo Kong, Viviana Rosero, Paola Caselli, Giuliana Cosentino

SiO

To study the early phases of massive star formation, we present ALMA observations of SiO(5-4) emission and VLA observations of 6 cm
continuum emission towards 32 Infrared Dark Cloud (IRDC) clumps, spatially resolved down to ≲0.05 pc. Out of the 32 clumps, we
detect SiO emission in 20 clumps, and in 11 of them the SiO emission is relatively strong and likely tracing protostellar outflows. Some
SiO outflows are collimated, while others are less ordered. For the six strongest SiO outflows, we estimate basic outflow properties. In
our entire sample, where there is SiO emission, we find 1.3 mm continuum and infrared emission nearby, but not vice versa. We build
the spectral energy distributions (SEDs) of cores with 1.3 mm continuum emission and fit them with radiative transfer (RT) models. The
low luminosities and stellar masses returned by SED fitting suggest these are early stage protostars. We see a slight trend of increasing
SiO line luminosity with bolometric luminosity, which suggests more powerful shocks in the vicinity of more massive YSOs. We do notsee a clear relation between the SiO luminosity and the evolutionary stage indicated by L/M. We conclude that as a protostar
approaches a bolometric luminosity of ~102L⊙, the shocks in the outflow are generally strong enough to form SiO emission. The VLA 6
cm observations toward the 15 clumps with the strongest SiO emission detect emission in four clumps, which is likely shock ionized jets
associated with the more massive ones of these protostellar cores.

1.3mm

L (5GHz) vs Pout

SiO
high mass
low mass

6cm

19: Massive Protocluster of a Periodic Maser Source G188.95+0.89
M. M. Mutie, J. O. Chibueze, K. El Bouchefry, G. C. MacLeod, J. Morgan, P. BakiWe report the results of ongoing monitoring of the 6.7 GHz CH3OH masers associated with G188.95+0.89. In these observations fivefeatures are periodically varying and at least two exhibit evidence of velocity drifts. It is not clear the cause of these velocity drifts. The
spectra have varied significantly since detection in 1991. The 11.45 km s-1 feature has decreased exponentially from 2003.
Complementary ALMA 1.3 mm continuum and line observational results are also presented. Eight continuum cores (MM1 - MM8) weredetected in G188.95+0.89. We derived the masses of the detected cores. G188.95+0.89 MM2 was resolved into 2 continuum cores(separated by 0.1 arcsec) in ALMA band 7 observations. Also CH3OH (4(2,2)-3(1,2)) thermal emission associated with MM2 is double
peaked. We propose the presence of multiple (at least binary) young stellar objects in MM2. SiO emission exhibit a bow-shock
morphology in MM2 while strong emission of 12CO at the east and west of MM2 suggest the presence of an east-west bipolar outflow.

395⽇20: Proper motions of spectrally selected structures in the HH 83 outflow
T.A. Movsessian, T.Yu. Magakian, A.V. Moiseev

We continue our program of investigation of the proper motions of spectrally separated structures in the Herbig-Haro outflows with the aidof Fabry-Perot scanning interferometry. This work mainly focuses on the physical nature of various structures in the jets. The aim of thepresent study is to measure the proper motions of the previously discovered kinematically separated structures in the working surface ofthe HH 83 collimated outflow. We used observations from two epochs separated by 15 years, which were performed on the 6m telescopewith Fabry-Perot scanning interferometer. We obtained images corresponding to different radial velocities for the two separate epochs, andused them to measure proper motions. In the course of our data analysis, we discovered a counter bow-shock of HH 83 flow with positive
radial velocity, which makes this flow a relatively symmetric bipolar system. The second epoch observations confirm that the working
surface of the flow is split into two structures with an exceptionally large (250 km s−1) difference in radial velocity. The proper motions ofthese structures are almost equal, which suggests that they are physically connected. The asymmetry of the bow shock and the turning ofproper motion vectors suggests a collision between the outflow and a dense cloud. The profile of the Hα line for the directly invisible
infrared source HH 83 IRS, obtained by integration of the data within the reflection nebula, suggests it to be of P Cyg type with a broad
absorption component characteristic of the FU Ori like objects. If this object underwent an FU Ori type outburst, which created the HH 83
working surfaces, its eruption took place about 1500 years ago according to the kinematical age of the outflow.