SF newsletter 375 No. 40-54
百瀬宗武（茨城大）
No. 47/53/49を中心に

47. Survival of the long-lived inner disk of PDS 70

Paola Pinilla, Myriam Benisty, Rens Waters, Jaehan Bae, Stefano Facchini F The K7 T Tauri star PDS 70

remains the best laboratory for investigating the influence of giant planet formation on the structure of the parental
disk. One of the most intriguing discoveries is the detection of a resolved inner disk from ALMA observations that
extends up to the orbit of PDS 70b. It is challenging to explain this inner disk because most of the dust particles
are expected to be trapped at the outer edge of the gap opened by PDS 70b and PDS 70c. By performing dust
evolution models in combination with radiative transfer simulations that match the gas disk masses obtained fromrecent thermo-chemical models of PDS 70, we find that when the minimum grain size in the models is larger than
0.1µm, there is an eﬃcient filtration of dust particles, and the inner disk is depleted during the first million year of
dust evolution. To maintain an inner disk, the minimum grain size in the models therefore needs to be smaller than
0.1µm. Only when grains are that small are they diﬀused and dragged along with the gas throughout the gap openedby the planets. The small grains transported in the inner disk grow and drift into it, but the constant reservoir of dust
particles that are trapped at the outer edge of the gap and that continuously fragment allows the inner disk to refill on
million-year timescales. Our flux predictions at millimeter wavelength of these models agree with ALMA observations.
These models predict a spectral index of 3.2 in the outer and 3.6 in the inner disk. Our simple analytical calculations
show that the water emission in the inner disk that was recently observed with the James Webb Space Telescope may
originate from these ice-coated small grains that flow through the gap, grow, and drift toward the innermost disk
regions to reach the water snowline.

70cが存在，このリングの内側にあるよりコンパクトな• リングの中に2つの惑星PDS70b,
Benchmarking the IRDC G351.77-0.53: Gaia DR3 distance, mass distribution, and star

48.

•
•

formation
content
inner
diskはどうしてある？

S. D. Reyes-Reyes, A. M. Stutz, S. T. Megeath, Fengwei Xu, R. H. Álvarez-Gutiérrez, N. Sandoval-Garrido, H.
-L. Liu F While intensively studied, it remains unclear how the star formation (SF) in Infrared Dark Clouds (IRDCs)

comparestothatof
nearbyclouds.
We
study
G351.77-0.53(henceforthG351),acluster-forming
filamentary
IRDC.
リング内壁のfiltrationを乗り越えられるくらい小さい0.1μmスケールのダストが必要
We begin by characterizing its young stellar object (YSO) content. Based on the average parallax of likely members,
we obtain a Gaia distance of ⇠ 2.0 ± 0.14 kpc, resolving the literature distance ambiguity. Using our Herschel-derived
N(H2 ) map, we measure a total gas mass of 10200 M (within 11 pc2 ) and the average line-mass profile of the entire星のごく近くまでの水の運び手としても興味深い
filament, which we model as = 1660(w/pc)0.62 M pc 1 . At w < 0.63 pc, our profile is higher and has a steeper

PDS 70/ALMA view
Isella et al. 2019

Benisty et al. 2021

• 5.4 Myr old; long lived で観測可能な inner diskが存在できる条件は？

方法• 2D HD simulation of disk + planet interaction (70b: 5MJ, 70c: 2.5MJ, α = 10-3) で1Myr くらいたった定常状態での方位角平均を，背景の1Dガス円盤‣ 初期Mdisk = 9 x 10-4M⦿
• Dust：成長＋移動を考慮した時間発展を計算する‣ 初期size分布：n(a) ∝ a-3.5, [amin, 10-4]cm with amin = 1x10-6, 1x10-5, 5x10-5‣ ρ=0.85 g cm-3 (vac. = 40% vol, sil. = 10%, C=20%, wat. = 30%) ; 破壊速度 = 10m/s‣ 初期 g/d = 100• 観測結果と比較したい場合は，得られた結果をradmc 3Dで計算

結果：Dust evolution
P. Pinilla et al.: Survival of the long-lived inner disk of PDS 70

縦の列が 初期の

amin が違うものの時間発展←1Myr←10Myramin = 10-6 cmの場合は，
amin = 5x10-5 cmに比べ，20au以内のダスト著しく多い
Fig. 1. Results from dust evolution models for the PDS 70 disk. Specifically, dust density distributions after 1 Myr (top panels) and 10 Myr (bottom
panels) of evolution as a function of grain size (y-axis) and distance from the star (x-axis). The di↵erence in simulations is the minimum grain sizein the initial dust size distribution, that is, decreasing from the left to the right column. The y-axis is di↵erent for each column because the grain
size grid depends on the initial grain size that is assumed (given in the title of each column).

after
10 Myr ofveris
ainitial= [5⇥1010evolution,] cm, whichThisefficientminimum
grain
size. Asfiltration
expected,cath
at theof theofgap
createddialouter
dustedge
velocity
particles,
ficient in this case. At 1 Myr of evo
were initially within the gap have ds
3
1 little@dafter 10 Myr of r,gas
evolution, very
=
+
3This
r,dustefficient
filtrationcan2
1 be und⇢
1 + StSt+Stgdial dust velocity of particles, which

lated at the midplan

16au以内のダスト質量の時間変化

proofs: manuscript no. PDS70

olar angle.
evolution
evolution
sumed 32
each parstiel et al.

(2)evolutionles calcu-(3)
A similar

a⇢ ⇡
,
St =
⌃ 2

where 3動径移動速度r,gas is the radial gas v
witha as thethegasvolumedensity,
3r,gas1 grain@r Pand ⌦,+3r,dust = Only 2when
1r,dust is
3
posit
⇢⌦
1 + StSt was+ St used
procedurepliesリングの内壁において，
that particles larger thanistheradialgas
velocity,
whereet3r,gasal.
(2021).
Pinillaetal.
(2012),
with
ガスと一緒に流れ込めずにfilterされる
the gas volume density, and ⌦ is the K
最小サイズ

Only when 3r,dust is positive areplies that particles
largerthan
critical⇢⌦⌃
23r,gasg
Pinillaet al.&(2012), withacritical.

@r P⇡⇢ s
3. Results

Fig. 2. Total dust disk mass within 16 au as a function of time for the
これより小さなものがあれば内側へと
23r,gas ⇢⌦⌃g
Because
all
the
terms
in
Eq
models of Fig. 1
acritical &供給が続く .

3.1. Dust density d(3)10Myrたったときのdustサイズ分布

gas surface density. A similar
Pohl et al. (2017) and Pinilla

Fig. 2. Total dust disk mass within 16 au as a function of time for themodels of Fig. 1

amin = 10-6 cmの場合

distribution after 1 Myr (top) of evolution as a function
star. The y-axis of each colon the initial grain size thathe title of each column). Theline), which is proportionalm the hydrodynamical simu-

rresponds to models whereis our model with the largest
he filtration of dust particles
d by the planets is very efolution, the dust grains thatdrifted toward the star, anddust is left in the inner disk.
nderstood in terms of the ra-

最大サイズには半径依存性ありFig. 3. Grain size distribution at radial distances of 5, 10, and 15 au(this means inside the orbit of PDS 70b) for the models where ainitial =[1 ⇥ 10 6 10 4 ] cm. The dotted line shows the MNR distribution at
10 au for comparison.

リアルなデータと模擬観測比較
P. Pinilla et al.: Survival of the long-lived inner disk of PDS 70

Fig. 4. Comparison between models and ALMA observations of PDS 70. Left panel: ALMA dust continuum emission at 855 µm from Benisty
et al. (2021) vs. synthetic images at the same wavelength taking the models of Fig 1 after 1 Myr of evolution. The beam for the synthetic images
is assumed to be as in the observations, i.e., ⇠0.046”⇥0.36” with a position angle of 51.5 .

model where ainitial = [5 ⇥ 10 5 10 4 ] cm, this mass is reduced
to 3.3 ⇥ 10 4 M (or 0.025 MMoon ) after 1 Myr of evolution, and6

Köhler et al. 2015; Jones et al. 2017; Hensley & Draine 2023),
which can also a↵ect the inferred dust mass from the inner disk

さまざまなバンドでの予測
P. Pinilla et al.: Survival of the long-lived inner disk of PDS 70

Fig. 5. Models and observational predictions for PDS 70disk. Left:Comparison of the azimuthally averaged radial intensity profiles of the deprojected images of the continuum from ALMA Band 7 observations (crosses) and the synthetic images from Fig. 4. The shaded area is the standard
deviation of each elliptical bin divided by the square root of the number of beams spanning the full azimuthal angle at each radial bin. Right:
Predictions for several ALMA bands for the case where ainitial = [10 6 10 4 ] cm, assuming that all the images have the same resolution as theobservations in Band 7 (Fig. 4).

1-3.5 Myr, where most of the material comes from the potential

議論など

Fig. 5. Models and observational predictions for PDS 70disk. Left:Comparison
jected images of the continuum from ALMA Band 7 observations (crosses) an
deviation of each elliptical bin divided by the square root of the number of b
Predictions for several ALMA bands for the case where ainitial = [10 6 10 4
observations in Band 7 (Fig. 4).

1-3.
repl
grat
the
befo
seen

• 1枚前のスライドと関連して：Inner diskとouter ringでは
spectral indexが微妙に異なると予想• ガスの面密度が最も大きな不定性（St → a_critical)• 内側への水氷の供給：小さなダストの存在が必要‣ 太陽系の地球型惑星領域への水の供給とも関連

Fig. 6. Total millimeter flux as a function of wavelength from thesame ALMA bands as in the right panel of Fig. 5 (case of ainitial =[10 6 10 4 ] cm). The fluxes are calculated in three di↵erent regions(as denoted in the right panel of Fig. 4), the inner disk (r<16 au), thegap (16 au < r <36 au), and the ring (36 au < r <112 au). The dashedline shows the best power-law fit to the data and the spectral index foreach region.

grains are of great importance to explain this water emission for
two reasons: First, small grains can help to shield ultraviolet lightand prevent H2 O photodissociation (Heays et al. 2017), and second, they can be the particles that can travel across the gap andenrich the inner disk, as demonstrated in this work.
We calculated the total dust mass that potentially reaches thesnowline in PDS 70 by taking the dust-loss rates ( Ṁdust ) at the
inner edge of the simulations in Sect. 2, and integrating over either 0-1 Myr, where the vast majority of the accreted dust comesfrom the initial material that was inside the gap location, or over

the
bou
for
twee
ainitiainiti
whi
assu
sum
like
et a
cien
part
por
of th
plan
colu
(i.e.
slab
NH2

whe
and
✏plan
1019
✏plan
latio

Myr.

53. Multiple Outflows around a Single Protostar IRAS 15398 3359

Jinshi Sai, Hsi-Wei Yen, Masahiro N. Machida, Nagayoshi Ohashi, Yusuke Aso, Anaëlle J. Maury, Sébastien
Maret F We present the results of our mosaic observations of a single Class 0 protostar IRAS 15398 3359 with

Atacama Compact Array (ACA) in the CO J = 2-1 line. The new observations covering a ⇠ 20 square region revealed
elongated redshifted and blueshifted components, which are located at distances of ⇠ 3000 -7500 on the northern andsouthern sides of the protostar, respectively, in addition to the previously observed primary and secondary outflows.
These elongated components exhibit Hubble-law like velocity structures, i.e., an increase of velocity with increasing
distance from the protostar, suggesting that it is the third outflow associated with the protostar. Besides, a newredshifted component is detected at radii of ⇠ 4000 -7500 on the northwestern side of the protostar. This redshiftedcomponent also exhibits a Hubble-law like velocity profile, which could be the counterpart of the secondary outflow
mostly detected at blueshifted velocities in a previous study. The three outflows are all misaligned by ⇠ 20-90 , andthe dynamical timescale of the primary outflow is shorter than those of the other outflows approximately by an orderof magnitude. These facts hint that the outflow launch direction has significantly changed with time. The outflow
direction may change if the rotational axis and the magnetic field are misaligned, or if the dense core is turbulent. We
favor the second scenario as the origin of the multiple outflows in IRAS 15398 3359 based on a comparison between
the observational results and numerical simulations.

ごく初期段階にあると見られる原始星
IRAS
15398-3359で，第3のアウトフ•
Modeling
JWST
MIRI-MRS
Observations
of
T
Cha:
Mid-IR
Noble
Gas
Emission
Trac54.
ing a Dense Disk Wind

ローコンポーネントを発見，第1，第2とお互いの軸が大きくズレている
Andrew D. Sellek, Naman S. Bajaj, Ilaria Pascucci, Cathie J. Clarke, Richard Alexander, Chengyan Xie, Giulia
Ballabio, Dingshan Deng, Uma Gorti, Andras Gaspar, Jane Morrison F [Ne II] 12.81 µm emission is a well-used••

tracer of protoplanetary disk winds due to its blueshifted line profile. MIRI-MRS recently observed T Cha, detecting
this
line
along
with
lines
of
[Ne
III],
[Ar
II]
and
[Ar
III],
with
the
[Ne
II]
and
[Ne
III]
lines
found
to
be
extended
複雑なアウトフロー構造の起源：turbulent
な環境下でのaccretion?
while the [Ar II] was not. In this complementary work, we use these lines to address long-debated questions about
protoplanetary disk winds regarding their mass-loss rate, the origin of their ionization, and the role of magneticallydriven winds as opposed to photoevaporation. To this end, we perform photoionization radiative transfer on simple
hydrodynamic wind models to map the line emission. We compare the integrated model luminosities to those observed
なぜ他で見つからない？：複雑なアウトフローはごく初期段階の特徴？
with MIRI-MRS to identify which models most closely reproduce the data and produce synthetic images from these toIRAS15398-3359• Lupus 領域にあるClass 0 Protostar，Singleらしい• d=155pc, Tbol = 50K, Lbol = 1.4L⦿
• これまで2つの軸がよくあっていないアウトフローが見つかっていた• 回転円盤から見積もられた中心星質量：M★ < 0.01M⦿ (Yen+ 2017; Okoda+
2018) → M★ = 0.02-0.1M⦿ (Thieme+ 2023)
12
今回はACAのモザイク，
CO(2-1)で分解能は悪いが広範囲(2’=0.09pc四方)を•カバー

Multiple Outflows in IRAS 15398

3

Moment 0/1（注: 1’ = 0.045pc)
第1の成分
第3の成分
New!

第2の成分

速度範囲を絞った積分強度分布4Sai et al.

(a)

(b)

NR1

NR2

WR

SEB

WB

SB

Figure 2. (a) High- and (b) low-velocity components of the CO J =2–1 emission. Red and blue colors show redshifted andblueshifted components, respectively. The LSR velocity range of each velocity component is shown in the top left corners in unitsof km s 1 . Contour levels are 3, 6, 12, 24, ... ⇥ , where 1 is the rms noise level. The rms of each map is 0.16 Jy beam 1 for thehigh-velocity redshifted and high-velocity blueshifted components, 0.20 Jy beam 1 for the low-velocity redshifted component,
and 0.46 Jy beam 1 for the low-velocity blueshifted component. The central crosses denote the protostellar position. The
ellipses at the bottom left corners indicate the synthesized beam size of 7.00 7 ⇥ 4.00 1 (87 ). The dashed lines in panel b show
directions of the position-velocity (PV) cuts.

PV図: NR1とSB
Multiple Outflows in IRAS 15398

(a)

SB

5

(b)

NR1

Figure 3. PV diagrams of the CO J =2–1 emission cut toward the (a) SB and (b) NR1 components. Contour levels are from 3,
6, 12, 24, ... ⇥ , where 1 is 0.13 Jy beam 1 . Black dots are data points tracing 5 contours that are used to fit the wind-driven
shell model. Most of error bars of the data points are smaller than the marker size. Black curves show velocity structures ofthe best-fit wind-driven shell models. The vertical and horizontal bars at the bottom left corners indicate the synthesized beam
size of 7.00 7 ⇥ 4.00 1 (87 ) and the velocity resolution of 0.16 km s 1 . The vertical and horizontal dashed lines denote the systemic
velocity of 5.4 km s 1 and the protostellar position, respectively.

Figure 3. PV diagrams of the CO J =2–1 emission cut toward the (a) SB and (b) NR1 components. Contour levels are from 3,
6, 12, 24, ... ⇥ , where 1 is 0.13 Jy beam 1 . Black dots are data points tracing 5 contours that are used to fit the wind-driven
shell model. Most of error bars of the data points are smaller than the marker size. Black curves show velocity structures ofthe best-fit wind-driven shell models. The vertical and horizontal bars at the bottom left corners indicate the synthesized beam
size of 7.00 7 ⇥ 4.00 1 (87 ) and the velocity resolution of 0.16 km s 1 . The vertical and horizontal dashed lines denote the systemic
velocity of 5.4 km s 1 and the protostellar position, respectively.

PV図: NR2とSEB
NR2

SEB

Figure 4. PV diagram of the CO J =2–1 emission cut
toward the NR2 component. Contour levels and symbols are
the same as those in Figure 3.

Figure 5. PV diagram of the CO J =2–1 emission cut
along the SEB component. Contour levels and symbols are
the same as those in Figure 3.

line passing through the central protostar, as shown in
Figure 2(b). The relationship of the NR2 component toFigure 5 shows a PV diagram cut toward the SEB
component (P.A.= 155 ). While the emission withinnd-driven shell model, the morphology and velocity
Wind-driven
Shellcavity
modelによるパラメータ見積もり
ructureof the outflow
are expressed as follows:R
v R = v0 ,R02

z = CR ,t al.
Table 1. Results of Wind-driven Shell Model Fitting
Lobes

SB
NR1
NR2

C sin i0.81 ± 0.02
1.24 ± 0.02
0.89 ± 0.02v0i

(km s 1 )( )0.1129 ± 0.0004
0.1017 ± 0.0006
0.0542 ± 0.0016

71.83 ± 0.05
74.24 ± 0.12
69.75 ± 0.71zvz = v0 ,z0(1)

Figure 6. (a) Same as Figure 2(b) but zoomed into the WB anddenote the directions and centers of the PV cuts, respectively. (and (c) WR filamentary structures centered their emission peaks.
and contour levels are the same as those in Figure 3. The vertica
5.4 km s 1 and the emission peak of the filamentary structures.
Table 2. Lengths, Velocities and Dynamical Timescales of the
Outflow Lobes
Lobes

SB
NR1
NR2

rCO

vmax,LSR

vmax,rel

0
⌧dyn

(au)

(km s 1 )(km s 1 )(104 yr)(104 yr)& 12, 000
& 12, 000
& 12, 000

1.72
8.12
7.32

3.68
2.72
1.92

& 1.5
& 2.1
& 3.0

& 0.49& 0.59
& 1.1

⌧dyn

0
Note—⌧dyn and ⌧dyn
are the dynamical timescales with andwithout inclination-angle correction, respectively, and ⌧dyn =0⌧dyn/ tan i.

大きなmisalignmentを示す複数アウトフローの起源は？
• Turbulent な環境下での accretion（一様でないangular momentumを持つ落下物質が落ち込み，円盤回転軸・アウトフロー軸がばたつく）• 初期のコア回転軸とB fieldのmisalignmentがアウトフローの捩れを招く• この天体：断定的はできないが，turbulent accretion の方が可能性高い‣ β = Eturb/EB がシミュレーションの想定よりさらに大きそう‣ 天球面上で，星間偏光から求めたBと速度勾配から示唆されるJとを比較す
ると，さほどズレてない

Multiple Outflows in IRAS 15398

s the dust temperature. F⌫ is measured to be 2.9 Jy
with a typical flux uncertainty of 10%. We adopt the
dust opacity ⌫ = 0.02 g 1 cm2 (Ossenkopf & Henning1994), and the dust temperature of 15 ± 5 K. The coreadius is estimated to be 6700 ± 800 au from the 3
ontour of the 850 µm continuum emission (Yen & the
Disk team 2024). The uncertainty of the core radiuss the standard deviation of the radii of the 3 contour,
which vary with the azimuthal angle. We used the 20
quare map of the C18 O J = 2–1 emission presented by
Sai et al. (2023) to measure the turbulent velocity in two
ways. One way is to measure the full width at half maxmum (FWHM) of a spectrum and subtract the thermal
ine width. The FWHM of the spectrum is measured
o be 0.50 ± 0.02 km s 1 within a circle with a radiusof 800 at an o↵ position, 4000 north of the protostellar
position, where systemic motions such as infall or rotaion are not observed. By assuming the gas temperature
ame as the dust temperature above, the non-thermalvelocity ( nth ) is estimated to be 0.20 ± 0.02 km s 1 .
This would give an upper limit of the turbulent velocityof the dense core, as the C18 O J = 2–1 emission may
nclude the surrounding cloud component. These paameters yield turb ⇠ 1.4 ± 0.9, where the uncertaintys calculated through the error propagation of the unertainty of each parameter. The calculated turbulent
nergy against the gravitational energy is much larger
han those in numerical simulations reporting the time
variation of the orientation of the disk normal.
The above calculation of the turbulent velocity may
overestimate the turbulence energy in the dense core.
The other way to estimate the turbulent velocity is to9

Figure 7. Summary of the configurations of the multiple
outflows and the possible orientations of the magnetic field
and the angular momentum vector of the dense core on theplane of the sky. Lobes drawn with solid and dashed curvesindicate the redshifted and blueshifted components of theoutflows, respectively.

なぜIRAS15398以外で見当たらないのか• turbulenceが殊更大きい？：Perseus 領域でのコアと比較すると，さほど大きいわけではない（下図）• 珍しい天体＝Short timescaleを示唆，ごく若い段階でのみ見られる？
Multiple Outflows in IRAS 15398

11

Figure 8. Histograms of the mass, non-thermal velocity, and the ratio of the turbulence energy to the gravitational energy ofthe dense cores in the Perseus star forming region from left to right, which are referred from Kirk et al. (2007). Vertical lines
show the parameters for the dense core of IRAS 15398 and grey shaded area indicate their uncertainties. Non-thermal velocities
are measured with the FWHM of the C18 O J = 2–1 spectrum for both Perseus dense cores and the dense core of IRAS 15398.

Based on the results of the numerical simulations andtion rate estimated for IRAS 15398 with the current lu-

We speculate that cloud youth and/or magnetic fields might account for the G351 ineﬃciency.

49. Observations of spiral and streamer on a candidate proto-brown dwarf

B. Riaz, D. Stamatellos, M. Machida F Spirals and streamers are the hallmarks of mass accretion during the earlystages of star formation. We present the first observations of a large-scale spiral and a streamer towards a very young
brown dwarf candidate in its early formation stages. These observations show, for the first time, the influence of
external environment that results in asymmetric mass accretion via feeding filaments onto a candidate proto-browndwarf in the making. The impact of the streamer has produced emission in warm carbon-chain species close to thecandidate proto-brown dwarf. Two contrasting scenarios, a pseudo-disk twisted by core rotation and the collision ofdense cores, can both explain these structures. The former argues for the presence of a strong magnetic field in browndwarf formation while the latter suggests that a minimal magnetic field allows large-scale spirals and clumps to form
far from the candidate proto-brown dwarf.

+(3-2)で観測し，広がったspiralProto-browndwarf
candidateの星周構造をALMAによるHCO
•
FAUST
XIII.
Dusty
cavityandmolecular
shock
driven
by
IRS7B
in
the
CoronaAustralis50.

clusterやstreamer構造を発見
FAUST collaboration - G. Sabatini et al. F The origin of the chemical diversity observed around low-mass protostars•••

probably resides in the earliest history of these systems. We aim to investigate the impact of protostellar feedback on
the chemistry and grain growth in the circumstellar medium of multiple stellar systems. In the context of the ALMACore
rotationとB-fieldの初期ミスアラインメント，もしくはdense
core同士の衝突？
Large Program FAUST, we present high-resolution (50 au) observations of CH3 OH, H2 CO, and SiO and continuum
emission at 1.3 mm and 3 mm towards the Corona Australis star cluster. Methanol emission reveals an arc-likestructure at ⇠1800 au from the protostellar system IRS7B along the direction perpendicular to the major axis of the
これらが仮に質量降着流に対応するのだとすると，比較的dynamicaltimescaleは長いのかもdisc. The arc is located at the edge of two elongated continuum structures that define a cone emerging from IRS7B.
The region inside the cone is probed by H2 CO, while the eastern wall of the arc shows bright emission in SiO, atypical shock tracer. Taking into account the association with a previously detected radio jet imaged with JVLA at
Warm
chain
(c-HCCCH)を検出：brown
6 cm, Carbon
the moleculararc molecule
reveals for the
first time a bow shock driven bydwarf周りで初めて！？
IRS7B and a two-sided dust cavity openedby the mass-loss process. For each cavity wall, we derive an average H2 column density of ⇠7⇥1021 cm 2 , a mass of⇠9⇥10 3 M , and a lower limit on the dust spectral index of 1.4. These observations provide the first evidence ofa shock and a conical dust cavity opened by the jet driven by IRS7B, with important implications for the chemicalenrichment and grain growth in the envelope of Solar System analogues.

観測結果

Spiral and streamer towards a candidate proto-BD

3(c)Tmb [K]

2

SpiralStreamer

1.5
1
0.5
0

4

5

6

7

8

9

10

11

Velocity [km/s]

Figure 1. (a-b) ALMA 1.16 mm continuum image. (c) ALMA HCO+ (3-2) spectrum. Dashed line marks the Vlsr for Ser-emb 16. (d) The moment 8 maps ofthe blue-shifted spiral and red-shifted streamer overplotted in positions. The contours are from 2-σ to 10-σ in steps of 2-σ. The 1-σ rms is ∼10 mJy beam–1 .
Ser-emb 16 continuum position is marked by a star.

Spiral/Streamerに4

Riaz, Stamatellos, Machida*+,!"#$%&2

対する
ピーク輝度-./0.$+ 1)!"#$%&3!"#$%&)!"#$%&(!"#$%&''44&5#!"#$%&$#'&(&$)"'*
012(mom8)，)*+%,-.
!"#$"%& '(積分強度 (mom0),)*+%,-//33-4+!"#

ピーク速度 (mom9)
クランピーな構造？
Spiral/streamerの中は速度が非常に一様

Figure 2. Moment maps in the HCO+ (3-2) line observations. (a) Moment 8 map for the spiral. (b) Moment 0 map for the spiral. (c) Moment 8 map for the
streamer. (d) Moment 0 map for the streamer. Ser-emb 16 continuum position is marked by a star. (e) Moment 9 map for the spiral and streamer. White contours
are the spiral structure seen in the moment 0 and 8 maps.

to the candidat
servational evid
triggered warmcomposition in
There is no c-H
streamer or at t
map.
c-HCCCH
formation of w
grain mantles inregion in the clo
ortho c-HCCCH
upper state ene
cm–3 . The H2 g
cm–3 (Table 1)
The detection owarm corino redensities are pr
reach values of

Spiral/Streamerとダスト放射の
位置関係
クランピーな構造？
Spiral/streamerの中は速度が非常に一様

6 THEORET

Figure 3. An overlap of the continuum emission (color map) with the spiral(top) and streamer (bottom) moment 8 maps plotted in red contours. The
contours are from 2-σ to 10-σ in steps of 2-σ. The 1-σ rms is ∼10 mJy
beam–1 .

While streamerstars and explai
Bate et al. 201
dense spiral aro
the first time. H
possible origin
methodology fo
Appendix A.
We consi
sented in (Macwhich the rotat
by an angle ran
simulations to
We find a modmatches the ob
The model map

c-HCCCHの検出
6 Riaz, Stamatellos, Machida
連続波ピークとは少しズレている

Figure 4. The moment 8 map in the c-HCCCH line (color raster map) compared with the moment 8 map for the streamer (yellow contours) and the continuu

シミュレーションと比較してみた

Figure 4. The moment 8 map in the c-HCCCH line (color raster map) compared with the moment 8 map for the streamer (yellow contours) and the continuum
emission (red contours). Red star marks the position for Ser-emb 16. The contours are from 2-σ to 10-σ in steps of 2-σ. The 1-σ rms is ∼10 mJy beam–1 inthe HCO+ line and ∼7 mJy beam–1 in the c-HCCCH line. Twisted Pseudo-disk(LとBがmisalign)

2.5

Tmb [K]

2
1.5

Core collision

(a)

Obs
TP
CC

1
0.5
Spiral and streamer towards a candidate proto-BD

0
5.5

6

6.5

7

VLSR [km s-1]

7.5

8

9

8.5

Figure 5. (a) Observed HCO+ (3-2) spectrum for the spiral (black) and the best model fits for the twisted pseudo-disk (TP) model (red) and the core collision(CC) model (blue). (b-c) Moment 0 maps from the best match to the observed spiral using the twisted pseudo-disk model and core collision model. Star marks
Spiral and streamer towards a candidate proto-BD 9
the position of the candidate proto-brown dwarf.

not happening head-on, which is the most likely scenario within star
どちらもそこそこ合う場合がある
forming
regions.
We thus have two contrasting scenarios to explain the observations. If the spiral is the pseudo-disk that initially formed along themagnetic field lines around Ser-emb 16 and has been twisted by theconsidered to be infalling material that has an external origin from aninhomogeneous material outside the star-forming core, while spirals
are considered to be infalling material with an internal origin fromthe envelope or pseudo-disk inside the core (e.g., Lee et al. 2023;
Goodwin et al. 2004; Bate et al. 2014; Machida et al. 2020; Yen et
Figure A1. Cartoons for the twisted pseudo-disk (top panel) and core collision (middle and bottom panels) models, respectively. The core collision snapshotsshow the column density (in g cm–2 ) at characteristic times during the evolution of the collision of the two cores.

Simultaneous FUV and NUV observations of T Tauri stars with UVIT/AstroSat: prob40. ing accretion process in young stars

Prasanta K. Nayak, Mayank Narang, P. Manoj, Uma Gorti, Annapurni Subramaniam, Nayana George, Chayan
Mondal F We present results from simultaneous FUV and NUV observations of T-Tauri stars (TTSs) in the Taurus

molecular cloud with UVIT/AstroSat. This is the very first UVIT study of TTSs. From the spectral energy distribution of TTSs from FUV to IR, we show that classical TTSs (CTTSs) emit significantly higher UV excess compared to
weak-line TTSs (WTTSs). The equivalent black-body temperatures corresponding to the UV excess in CTTSs (> 104K) are also found to be relatively higher than that in WTTSs (< 8500 K). From the UV excess, we have re-classified
two WTTSs (BS Tau, V836 Tau) as CTTSs, which has been supported by the follow-up optical spectroscopic study
using the Himalayan Chandra Telescope (HCT), showing strong H↵ line emission. We find that CTTS show strong
excess emission in both FUV (>107 ) and NUV (>103 ) bands, while WTTS show strong excess only in the FUV(.105 ), suggesting that excess emission in NUV can be used as a tool to classify the TTSs. We also find a linear
correlation between UV luminosity (a primary indicator of mass accretion) and H↵ luminosity (a secondary indicatorof mass accretion) with a slope of 1.21±0.17 and intercept of 2.18±0.56.

Episodic eruptions of young accreting stars: the key role of disc thermal instability due
41. to Hydrogen ionisation

Sergei Nayakshin, Fernando Cruz Saenz de Miera, Agnes Kospal, Aleksandra Calovic, Jochen Eisloﬀel, Douglas
N. C. Lin F In the classical grouping of large magnitude episodic variability of young accreting stars, FUORs outshine

their stars by a factor of ⇠ 100, and can last for up to centuries; EXORs are dimmer, and last months to a year. A disc
Hydrogen ionisation Thermal Instability (TI) scenario was previously proposed for FUORs but required unrealistically
low disc viscosity. In the last decade, many intermediate type objects, e.g., FUOR-like in luminosity and spectra but
EXOR-like in duration were found. Here we show that the intermediate type bursters Gaia20eae, PTF14jg, Gaia19bey
and Gaia21bty may be naturally explained by the TI scenario with realistic viscosity values. We argue that TI predicts
a dearth (desert) of bursts with peak accretion rates between Ṁ ⇠ 10 6 M /yr and Ṁ ⇠ 10 5 M /yr, and that thisdesert is seen in the sample of all the bursters with previously determined Ṁ burst. Most classic EXORs (FUORs)
appear to be on the cold (hot) branch of the S-curve during the peak light of their eruptions; thus TI may play a rolein this class diﬀerentiation. At the same time, TI is unable to explain how classic FUORs can last for up to centuries,
and over-predicts the occurrence rate of short FUORs by at least an order of magnitude. We conclude that TI is arequired ingredient of episodic accretion operating at R < 0.1 au, but additional physics must play a role at larger
scales. Knowledge of TI inner workings from related disciplines may enable its use as a tool to constrain the natureof this additional physics.

42. The Eﬀect of Starspots on Spectroscopic Age and Mass Estimates of Non-Accreting
T Tauri Stars in the Taurus-Auriga Star Forming
Region15

Facundo Pérez Paolino, Jeﬀrey S. Bary, Lynne A. Hillenbrand, Madison Markham F Accurate age and mass

determinations for young pre-main sequence stars are made challenging by the presence of large-scale starspots. We
present results from a near-infrared spectroscopic survey of ten T-Tauri Stars in Taurus-Auriga that characterize
spot filling factors and temperatures, the resulting eﬀects on temperature and luminosity determinations, and theconsequences for inferred stellar masses and ages. We constructed composite models of spotted stars by combining
BTSettl-CIFIST synthetic spectra of atmospheres to represent the spots and the photosphere along with continuum
emission from a warm inner disk. Using a Markov-Chain Monte-Carlo algorithm, we find the best-fit spot andphotospheric temperatures, spot filling factors, as well as disk filling factors. This methodology allowed us to reproduce
the 0.75-2.40 micron stellar spectra and molecular feature strengths for all of our targets, disentangling the complicatedmulti-component emission. For a subset of stars with multi-epoch observations spanning an entire stellar rotation, we
correlate the spectral variability and changes in the filling factors with rotational periods observed in K2 and AAVSO
photometry. Combining spot-corrected eﬀective temperatures and Gaia distances, we calculate luminosities and use
the Stellar Parameters of Tracks with Starspots (SPOTS) models to infer spot-corrected masses and ages for oursample of stars. Our method of accounting for spots results in an average increase of 60% in mass and a doubling inage with respect to traditional methods using optical spectra that do not account for the eﬀect of spots.

consequences for inferred stellar masses and ages. We constructed composite models of spotted stars by combining
BTSettl-CIFIST synthetic spectra of atmospheres to represent the spots and the photosphere along with continuum
emission from a warm inner disk. Using a Markov-Chain Monte-Carlo algorithm, we find the best-fit spot andphotospheric temperatures, spot filling factors, as well as disk filling factors. This methodology allowed us to reproduce
the 0.75-2.40 micron stellar spectra and molecular feature strengths for all of our targets, disentangling the complicatedmulti-component emission. For a subset of stars with multi-epoch observations spanning an entire stellar rotation, we
correlate the spectral variability and changes in the filling factors with rotational periods observed in K2 and AAVSO
photometry. Combining spot-corrected eﬀective temperatures and Gaia distances, we calculate luminosities and use
the Stellar Parameters of Tracks with Starspots (SPOTS) models to infer spot-corrected masses and ages for oursample of stars. Our method of accounting for spots results in an average increase of 60% in mass and a doubling inage with respect to traditional methods using optical spectra that do not account for the eﬀect of spots.

その他のアブストラクト
Chemical diﬀerentiation and gas kinematics around massive young stellar objects in
43. RCW 120

K. V. Plakitina, M. S. Kirsanova, S. V. Kalenskii, S. V. Salii, D. S. Wiebe F We present results of a spectral

survey towards a dense molecular condensation and young stellar objects (YSOs) projected on the border of the HII
region RCW 120 and discuss emission of 20 molecules which produce the brightest lines. The survey was performed
with the APEX telescope in the frequency range 200 – 260 GHz. We provide evidences for two outflows in the dense
gas. The first one is powered by the RCW 120 S2 YSO and oriented along the line of sight. The second outflow
around RCW 120 S1 is aligned almost perpendicular to the line of sight. We show that area with bright emission of
CH3 OH, CH3 CCH and CH3 CN are organised into an onion-like structure where CH3 CN traces warmer regions aroundthe YSOs than the other molecules. Methanol seems to be released to the gas phase by shock waves in the vicinityof the outflows while thermal evaporation still does not work towards the YSOs. We find only a single manifestationof the UV radiation to the molecules, namely, enhanced abundances of small hydrocarbons CCH and c-C3 H2 in thephoto-dissociation region.

44. Bayesian characterization of the young open cluster NGC 6383 using HDBSCAN and
Gaia DR3

L. M. Pulgar-Escobar, N. A. Henríquez-Salgado F This study focuses on determining the characteristics of theyoung open cluster NGC 6383. To achieve this, the HDBSCAN clustering algorithm is utilized to identify potential
cluster members based on proper motions and parallaxes from Gaia Data Release 3. Various parameters of NGC 6383,
such as tidal radius, core radius, distance through parallax and isochrone-fitting, proper motion, age, metallicity,and relevant others, are assessed. To perform this analysis, we utilize an extension of Hamiltonian Monte Carlo, theNo-U-Turn Sampler. The results of this analysis point out that NGC 6383 is a very young open cluster (⇠ 1 4 Myr),with a distance of ⇠ 1.1 kpc.

45. Mass assembly in massive star formation: a fragmentation study of ATLASGAL clumps

Jagadheep D. Pandian, Rwitika Chatterjee, Timea Csengeri, Jonathan P. Williams, Friedrich Wyrowski, Karl
M. Menten F The mass assembly in star forming regions arises from the hierarchical structure in molecular clouds

in tandem with fragmentation at diﬀerent scales. In this paper, we present a study of the fragmentation of massive
clumps covering a range of evolutionary states, selected from the ATLASGAL survey, using the compact configurationof the Submillimeter Array. The observations reveal a wide diversity in the fragmentation properties with about
60% of the sources showing limited to no fragmentation at the 2" scale, or a physical scale of 0.015 - 0.09 pc. We
also find several examples where the cores detected with the Submillimeter array are significantly oﬀset from theclump potential suggesting that initial fragmentation does not result in the formation of a large number of Jeans massfragments. The fraction of the clump mass that is in compact structures is seen to increase with source evolution.
We also see a significant correlation between the maximum mass of a fragment and the bolometric luminosity of theparent clump. These suggest that massive star formation proceeds through clump fed core accretion with the initial
fragmentation being dependent on the density structure of16the clumps and/or magnetic fields.

Paola Pinilla, Myriam Benisty, Rens Waters, Jaehan Bae, Stefano Facchini F The K7 T Tauri star PDS 70

remains the best laboratory for investigating the influence of giant planet formation on the structure of the parental

Physical Properties and Kinematics of Dense Cores Associated with Regions of Massive
46. disk.
of the mostfrom
intriguingis theStarOneFormation
the discoveries
Southern
Skydetection of a resolved inner disk from ALMA observations that

extends
up to theorbitof PDS 70b. E.
It M.
is challenging
to explain
this inner
disk
becausemost ofobservations
the dust particles
L. E. Pirogov,
P. M.
Zemlyanukha,
Dombek, M.
A. Voronkov
F The
resultsof spectralin theareexpected
to frequency
be trappedat theouteredgeinofthe
thesouthern
gap opened
by PDS 70b
andcores
PDSand70c.
By performing
dust
⇠ 84
92 GHzrange
of sixobjects
sky containing
dense
associatedwith regions
evolutionin combination
radiative
transfer simulations
that matchgas out
diskwith
massesfromof massivemodels
stars andstar clusters withformation
are presented.
The observations
were thecarriedthe obtained
MOPRA-22m
recentthermo-chemicalof PDS 70,
we findwhen the minimum
grain(LTE)size inapproximation,
the models is thelargerthanradio telescope.
Withinmodels
the frameworkof thelocalthat
thermodynamic
equilibrium
column+0.1µm,
there
an eﬃcientoffiltrationof dustparticles,
anddepleted
yearareof
H13 CO, HN13C, theHC3innerN, c-Cdisk
CH3 Cduring
CHfirstmolecules
densities
and isabundances
the H13 CN,
3 H2 ,isSiO,
2 H andthe
3 CNmillion
dust
evolution.
To maintainan temperatures
inner disk, the(⇠minimum
grain
in the models
therefore
be virial
smallerthancalculated.
Estimatesof kinetic
30 50 K),
sizessizeof emission
regions(⇠ 0.2 needs
3.1 pc)toand
masses0.1µm.
are thatThesmallthey diﬀused
and cores
draggedalong with
with increasing
the gas throughout
the gap
are obtained.
linearewidthsin the threedecrease
distance fromthe opened
center.
(⇠ 70 Only
4600 whenM ) grains+by
The small grains
in opticallythe inner thickdisk growintoandit, but
the constantreservoirof dust(1-0)
HCN(1-0)
is observed,
indicating
In thefourplanets.
cores, asymmetry
in the transported
profiles of thelines and
HCOdriftparticlesthat ofaresystematic
trapped atmotions
the outer
edgetheof linethe gap
and that
continuously
fragment allows
thecaused
inner disk
to refill on
the presencealongof sight.
In twocases, the asymmetry
can beby contraction+
million-year
Our flux
at millimeter
wavelengthof these models
with ALMA
observations.
and H13 CO(1-0), obtained
within agree
the frameworkof thenon-LTEof gas. Thetimescales.
model spectral
mapspredictionsof HCO+ (1-0)
Thesemodelspredict a model,
spectralareindex
of 3.2
theobserved
outer andones.
3.6 inThe
the radial
inner disk.
Ourcalculations
turbulent
sphericallysymmetric
fittedintointhe
profilesof simple
densityanalytical(/ r 1.6 ),
0.2
show
that(/
theemissionin the velocity
inner disk
recentlyobserved corewith have
the James
Webb SpaceThe
Telescopemay
velocityr water), andcontraction(/thatr0.5 )wasin theG268.42–0.85
been calculated.
contraction
originatefrom thesegrainsthatinflow
through
the fallgap,of grow,anda drift
towardinnermost), and in diskthevelocity profile
diﬀersice-coatedfrom thatsmall
expectedboth
the caseof freegas onto
protostar
(/the
r 0.5
regionsreachthecollapse
water snowline.
case of toglobalcore(contraction velocity does not depend on distance). A discussion of the obtained results isprovided.
correction for our YSO catalog relative to Spitzer surveys of Orion A. The G351 SFE is ⇠ 1.8 times lower than that ofBenchmarking
the theIRDC
G351.77-0.53:
GaiaWeDR3
distance,
distribution,
andstar
medianvalue for local clouds.
measureSFR andmass
gas masses
to estimate theeﬃciency
48. Orion A and lower thancontent
Survivalthe✏↵ .long-livedof PDS
70 previously proposed mean local relation, and ⇠ 4.7⇥
We find thatinner✏↵ is ⇠disk
1.1 dexbelow theperfree-fall oftime,
47. formation
S.
D. Reyes-Reyes,
A. observations
M.
Stutz, S.
T. Megeath,Fengwei
Xu, R.
H.doÁlvarez-Gutiérrez,
H.
Paola
Pinilla,Benisty,
Rens
Waters,Bae,
StefanoFacchini
The N.
K7 Sandoval-Garrido,
T
Tauri in
star
70
below
Orion
A. Myriam
These
indicatethat Jaehan
local
SF-relations
notcaptureFvariations
present
thePDS
Galaxy.
-L.
Liu
Fthe
While
intensively
studied,it remains
unclearhow
thestar planet
formation(SF) in
Dark Clouds
remains
best
laboratory
for and/or
investigatingtheinfluenceof
giant
formation
onInfrared
the structureof the (IRDCs)
parentalWe
speculatethat
cloud youth
magnetic
fieldsmight
account
for theG351
ineﬃciency.
comparesnearbyclouds.discoveries
We studyisG351.77-0.53
G351),
cluster-forming
IRDC.
disk. Onetoofthat
the ofmost
intriguingthe detection(henceforthof a resolved
inneradisk
from ALMAfilamentary
observations
thatWe
beginupbyto
characterizing
its youngobject (YSO)
content.thisBasedon disk
the average
extends
the orbit of PDS
70b. stellar
It is challenging
to explain
inner
becauseparallax
most of ofthelikely
dustmembers,
particles
Observations
oftrappedspiralstreamercandidate
proto-browndwarf
a Gaiadistanceof ⇠2.0
0.14 kpc,
theliteratureambiguity.
Using
areobtain
expected
to be
atand
the±outeredgeresolving
ofon
the agap
openedbydistance
PDS 70b
and PDS
70c. our
By Herschel-derived
performing dust
49. weB.
Riaz,
D.
Stamatellos,
M. Machida
FofSpiralsand (withinstreamers
hallmarks
mass
accretion
duringtheearly
wemeasurea totalgas
mass
10200transfer
M
11 arepc2 )theandthe averageline-mass
profileof theentireN(Hevolutionmodelsin combination
withradiative
simulations
that
match
theof gasdisk
massesobtainedfrom2 ) map,
0.62
stagesstar formation.
We
the70,
firstweobservations
large-scale
spiralanda streamer
towards
alargervery
young
M thatpc 1when.ofAta w
0.63 pc,
ourprofilehigherand ishasa steeperfilament,which
we modelmodels
as present=of1660(w/pc)
recent ofthermo-chemicalPDS
findthe< minimum
grain
size
inisthemodelsthanbrowncandidatein itsearlyformation
stages.
These
for during
the first
the influence
power-law
index
than
profilesextracted
in particles,
Orion
A and
most
of itsdisk
substructures.
Based
on
the
inside0.1µm, dwarf
there
is
an
eﬃcient
filtrationof dustandthe observations
inneris show,
depleted
thetime,firstYSOs
millionyeartheofof
external
environmentthat resultsinasymmetricmassviafilaments
onto
a candidate
proto-brown
filament
area,
weToestimate
theeﬃciency(SFE)
andaccretion
SF
rate(SFR).
calculatea factor
ofto5 beincompletenessdust evolution.
maintain
an SF
inner
disk, theminimum
grain
size
infeedingthe Wemodelstherefore
needs
smaller
than
dwarf
the
The
impactof thestreamerhas produced
emission
inwithwarm
close
to the0.1µm.inOnly
whengrains
are
that
small
they surveys
diﬀusedanddraggedalong
thecarbon-chain
the thangap
openedcorrection
for making.
our
YSO
catalogrelative
toare
SpitzerofOrion
A. The
G351
SFE
isgas
⇠ throughout
1.8 timesspecies
lower
that
of
candidate
proto-browndwarf.
Two
contrasting
scenarios,a pseudo-disk
twistedbybut
corerotationandtheby theAplanets.
Thethansmalltransported
theinner diskgrow
and SFR
drift
into
it,
the
constant
reservoirof dustof
Orion
and
lower
thegrains
medianvalue
for inlocal
clouds.
We
measureand gasmassesto estimate
thecollisioneﬃciency
dense
cores,
canthesestructures.
The
arguesfor the presence
ofmeanaallows
strongfield
inparticlesthat
arebothtrappedtheoutergapformer
and17that
continuously
fragment
themagnetic
inner disk
to refill
on
We at
find
that
✏↵ edgeis ⇠ of1.1the
dex
below
the
previously
proposed
local
relation,and⇠ brown
4.7⇥
perfree-falltime,✏↵ . explain
dwarf
formation
while observations
thesuggeststhat
minimalmagnetic field
allowslarge-scaleand clumps
to form
million-yeartimescales.
Ourlatter
flux predictions
at amillimeter
wavelengththesemodelsagree spirals
withpresent
ALMA
below
Orion
A. Theseindicatethatlocal SF-relations
doofnot
capturevariations
inobservations.
the Galaxy.
Thesemodelspredict
a proto-brown
spectralindex
of
3.2 in theouterand account
3.6 in the
disk. Oursimple analytical calculations
far
fromthe candidate
dwarf.
We
speculate
that
cloud
youth and/or
magnetic
fieldsmight
forinner
the G351
ineﬃciency.
show that the water emission in the inner disk that was recently observed with the James Webb Space Telescope may
originate from these ice-coated small grains that flow through the gap, grow, and drift toward the innermost disk
FAUST
XIII.theDusty
cavityand moleculardrivenby IRS7B in
the Corona Australisofspiraland streamer
on a shockcandidate
proto-brown
dwarf
49.
regions to reachwatersnowline.
50. Observations
clusterB.
Riaz, D. Stamatellos, M. Machida F Spirals and streamers are the hallmarks of mass accretion during the early
FAUST
et al.
Fobservations
The origin ofofthe
chemical diversity
observedaroundlow-mass
protostars
stagesof collaboration
star formation.- G.
WeSabatinipresent thefirsta large-scale
spiral anda streamer
towards
a veryyoung
Benchmarking
theearliest
G351.77-0.53:
Gaia
mass
and
starofprobably
residesin thehistoryof thesestages.
systems.
We DR3aim
to distance,
investigate
theimpactof protostellar
feedbackondwarf
candidate
inIRDCits early
formationThese
observations
show,
for
thedistribution,
firsttime, the influence
48. brownformation
contentthechemistryand grain
growthcircumstellar
mediumof multiple
stellarsystems.
In athecontext of
the ALMA
external
environmentthat
resultsininthe
asymmetricmassaccretion
via feeding
filaments
onto
candidate
proto-brown
S. D. inReyes-Reyes,A.
M.
Stutz,S.
T.
R.
H. Álvarez-Gutiérrez,
N. andSandoval-Garrido,
H2 CO,
SiO andclose
continuum
Large
Program
FAUST,
weimpact
present(50producedau)Xu,
observations
ofinCH3 OH,
dwarf
the making.
Theof high-resolution
theMegeath,streamer Fengwei
hasemissionwarm
carbon-chain
speciesto H.
the-L. Liu Fat
Whileintensively
it remains
unclear
how
star
(SF)
Infrared
Dark
Clouds(IRDCs)emission
1.3 mmand3 studied,mm
towards
the Corona
Australis
starformation
cluster.
Methanolemission
revealsanarc-like
candidate
proto-browndwarf.
Two
contrasting
scenarios,
a thepseudo-disk
twistedby incorerotationandthe collisionofcomparestothatof
nearbyclouds.
We
study
G351.77-0.53(henceforthG351),acluster-forming
filamentary
IRDC.
structure
atcan
⇠1800
from theprotostellar
IRS7Bargues
along thedirection
perpendicular
to the majorof thedense
cores,
bothauexplain
these
structures.system
The former
for thepresenceof a strong magnetic
fieldaxisin brown
We beginbyits youngobject(YSO)
content.
Basedonthattheaveragea parallax
of likely
members,
disc.
The
arccharacterizing
is while
locatedtheedge
ofstellar
twoelongated
continuum
structures
definecone
emerging
fromdwarf
formation
theatlattersuggeststhata minimal
magnetic
fieldallowslarge-scale
spiralsandclumpstoIRS7B.
form
we
obtainaGaia
distance
of
⇠
2.0
±
0.14
kpc,
resolvingtheliterature
distance
ambiguity.
Using
our
Herschel-derived
Thefromregionthe proto-browncone is probedby H2 CO, while the eastern wall of the arc shows bright emission in SiO, afar
the insidecandidatedwarf.
measurea totalmass ofthe
10200
M (withinpc2 ) and theaverageradio
line-mass
profilewithof theentireat
N(H2 ) map,
typicalshockwetracer.
Takingintogasaccount
association
with11a previously
detected
jet imaged
JVLA
0.62
1
pc shock. At w< 0.63our andprofileis higher dust
and hasa steeper
we modelas =for1660(w/pc)
6filament,
cm, thewhichmolecular
arc reveals
the first timeM
a bow
drivenbypc,
IRS7B
a two-sided
cavityopened
21
2
FAUST
XIII.
Dusty
cavityandmolecular
shock
driven
by
IRS7B
in
the
CoronaAustralis
power-lawindex thanextracted
in Orion
A andanmostof itsHsubstructures.
Based on the YSOs
theof
cm inside, a mass
the mass-loss
process.profiles
For eachcavity wall,
we derive
average
2 column density of ⇠7⇥10
50. bycluster
filament 3area,andSF rate(SFR).
Weobservations
calculate a provide
factor ofthe
5 incompletenessM , weandestimate
a lower thelimitSFoneﬃciency
the dust (SFE)
spectralindex
of 1.4.
These
first evidence of
⇠9⇥10
FAUST
G. Sabatini
et al. Fof thebychemical
observedimplications
around low-mass
protostars
a shock collaboration
and a conical -dust
cavity opened
byThe
the origin
jet driven
IRS7B, diversity
with important
for thechemicalprobably
residesthegrowthearliestinhistoryof theseofsystems.
We aimto investigate the impact of protostellar feedback onenrichment
and ingrain
the envelope
Solar Systemanalogues.
the chemistry and grain growth in the circumstellar medium
17 of multiple stellar systems. In the context of the ALMA

51.

Zúñiga, Nuria Calvet, Cesar Briceño, Ricardo López-Valdivia, Marina Kounkel, Guy S. Stringfellow, Keivan
Foreground
Dust
Properties
towards
the Cao,
ClusterG. Stassun, Marc
Pinsonneault,
Lucia
Adame, Lyra
KevinNGC
Covey,7380
Amelia Bayo, Alexandre Roman-Lopes,
Sadhana
JeewanC. Pandey,
Thiem
Neelama Panwar,
Biman
J. Medhi,
VishalShashikiran
ChristianSingh,
Nitschelm,
RichardR. LaneF Hoang,
We developed
grid of stellar
rotationmodelsfor Joshi,
low-mass
and solarGanesh
F Usingstarlight
we present
propertiesof foregrounddust towards
cluster NGC
7380< M⇤ the< 1.2M). Thesemodels incorporate
the star-disk
interaction
type ClassicalT Tauristarspolarization,(CTTS) (0.3M

embeddedin Hii region
Sh 2-142.
of starlightare rotation
carried out
four
using
and magnetosphericejectionsto Observations
investigate theevolutionpolarizationof the stellar
ratein asa filtersfunctionof antheimaging
mass ofpolarimeterwith afield
104-cmARIES
telescope.
vectorsof starsaligned along
theparameters
Galactic, the magnetic(B⇤ ),and stellar
windPolarization(Ṁwind ). We
compiled
andaredeterminedstellarthe star M⇤equippedmagnetic
field. Towards
east andsoutheastvelocity
regions,v thedustmass
structureappearsin M
otherregionsstellarthan
mass
for 208 CTTS,
such as the
projected
rotationalsin(i),
accretion
ratemuchṀacc ,denser⇤ , ages, and(inferred
extinction
contours
colourimage) anda isalso reflectedvalue
in polarization
distribution.
estimatedfrom
rotational
periods
usingandTESS
data.composite
We also estimatedrepresentativeof the mass-loss
rate forWe
ourfindthatusing
the polarization
degree line.
and extinction
to increase
and indication
foragreethe presence
a dustsamplethe [O I] spectral
Our resultstend
confirmthat vwith
sin(i)distancemeasurements
in CTTS
with theofrotation
layer
a distancearoundkpc. inWethe
have
identified eight potential
candidates
exhibiting
intrinsic
polarizationbyrates atprovidedby ofourspin 1.2
modelsaccretion-powered
stellar winds(APSW)
picture.
In addition,
we usedemploying
three distinct
criteria
to distinguishbetweenstarstoofexplore
intrinsicthe
polarizationinterstellar
polarizedstars.
the Approximate
BayesianComputation(ABC)
techniqueconnectionand
betweenthe model
parameters
For
polarizedproperties
stars, we findthat theWemaximum
degreewithagethe might
color excess
and has byaandinterstellar
the observationalof CTTS.
find thatpolarization
the evolutionof vincreases
sin(i) withbe regulated
strongscatter,withmean value
1.71±0.57%. The peak wavelength spans 0.40 0.88µm with the mean value ofvariationsin (1)
thetheintensityof Bof⇤ and (2) the fraction of the accretion flow ejected in magnetic winds, removing
0.56±0.07µm, suggestinggrain sizes
in youngest
the regionstars
as thediﬀuseinterstellar
medium.
The
polarization
angular momentum
from similar
these systems.
Thein average
our sample
(⇠1
Myr)
show
a
medianbranching
ratio
0.61
/A
/
A
.
Our
observational
results
arefound
eﬃciency
is
also
found
to
decreasewithvisualextinctionasPV⇠ 0.01Vand 1000
G, respectively, for stars with ages & 3
Ṁwind /Ṁacc ⇠ 0.16 and median B⇤ ⇠ 2000 G, in contrast to max
tobeconsistentwiththepredictions
bytheradiative
torquealignment
theory.
Myr.

52. Rotational Evolution of Classical T Tauri Stars: Models and Observations
Javier Serna, Giovanni Pinzón, Jesús Hernández, Ezequiel Manzo-Martínez, Karina Mauco, Carlos G. RománMultiple Outflows around a Single Protostar IRAS 15398 3359
53. Zúñiga,Nuria Calvet, Cesar Briceño, Ricardo López-Valdivia, Marina Kounkel, Guy S. Stringfellow, Keivan

Jinshi Sai, Hsi-Wei Yen, Masahiro N. Machida, Nagayoshi Ohashi, Yusuke Aso, Anaëlle J. Maury, Sébastien
G. Stassun, Marc Pinsonneault, Lucia Adame, Lyra Cao, Kevin Covey, Amelia Bayo, Alexandre Roman-Lopes,
Maret F We present the results of our mosaic observations of a single Class 0 protostar IRAS 15398 3359 with
Christian Nitschelm, Richard R. Lane F We developed a grid of stellar rotation models forlow-mass and solar0

Atacama Compact Array (ACA) in the CO J = 2-1 line. 18
The new observations covering a ⇠ 2 square region revealed). These models incorporate the star-disk interaction
type Classical T Tauri stars (CTTS) (0.3M < M⇤ < 1.2M
elongated redshifted and blueshifted components, which are located at distances of ⇠ 3000 -7500 on the northern andand magnetospheric ejections to investigate the evolution of the stellar rotation rate as a function of the mass ofsouthern sides of the protostar, respectively, in addition to the previously observed primary and secondary outflows.
the star M⇤ , the magnetic field (B⇤ ), and stellar wind (Ṁwind ). We compiled and determined stellar parameters
These elongated components exhibit Hubble-law like velocity structures, i.e., an increase of velocity with increasingfor 208 CTTS, such as projected rotational velocity v sin(i), mass accretion rate Ṁacc , stellar mass M⇤ , ages, anddistance from the protostar, suggesting that it is the third outflow associated with the protostar. Besides, a new
estimated rotational periods using TESS data. We00also00 estimated a representative value of the mass-loss rate for ourredshifted component is detected at radii of ⇠ 40 -75 on the northwestern side of the protostar. This redshifted
sample using the [O I] spectral line. Our results confirm that v sin(i) measurements in CTTS agree with the rotation
component also exhibits a Hubble-law like velocity profile, which could be the counterpart of the secondary outflow
rates provided by our spin models in the accretion-powered stellar winds (APSW) picture. In addition, we usedmostly detected at blueshifted velocities in a previous study. The three outflows are all misaligned by ⇠ 20-90 , and
the Approximate Bayesian Computation (ABC) technique to explore the connection between the model parameters
the dynamical timescale of the primary outflow is shorter than those of the other outflows approximately by an orderand the observational properties of CTTS. We find that the evolution of v sin(i) with age might be regulated byof magnitude. These facts hint that the outflow launch direction has significantly changed with time. The outflow
variations in (1) the intensity of B⇤ and (2) the fraction of the accretion flow ejected in magnetic winds, removing
direction may change if the rotational axis and the magnetic field are misaligned, or if the dense core is turbulent. We
angular momentum from these systems. The youngest stars in our sample (⇠1 Myr) show a median branching ratio
favor the second scenario as the origin of the multiple outflows in IRAS 15398 3359 based on a comparison betweenṀwind /Ṁacc ⇠ 0.16 and median B⇤ ⇠ 2000 G, in contrast to ⇠ 0.01 and 1000 G, respectively, for stars with ages & 3
the observational results and numerical simulations.
Myr.

Modeling JWST MIRI-MRS Observations of T Cha: Mid-IR Noble Gas Emission Trac54.
Multiple
Outflows
around a Single Protostar IRAS 15398 3359
53. ing a Dense
Disk Wind

Jinshi Sai, Hsi-Wei Yen, Masahiro N. Machida, Nagayoshi Ohashi, Yusuke Aso, Anaëlle J. Maury, SébastienAndrew D. Sellek, Naman S. Bajaj, Ilaria Pascucci, Cathie J. Clarke, Richard Alexander, Chengyan Xie, Giulia
Maret F We present the results of our mosaic observations of a single Class 0 protostar IRAS 15398 3359 with
Ballabio, Dingshan Deng, Uma Gorti, Andras Gaspar, Jane Morrison F [Ne II] 12.81 µm0 emission is a well-used

Atacama Compact Array (ACA) in the CO J = 2-1 line. The new observations covering a ⇠ 2 square region revealed
tracer of protoplanetary disk winds due to its blueshifted line profile. MIRI-MRS recently observed T Cha, detecting
elongated redshifted and blueshifted components, which are located at distances of ⇠ 3000 -7500 on the northern andthis line along with lines of [Ne III], [Ar II] and [Ar III], with the [Ne II] and [Ne III] lines found to be extended
southern sides of the protostar, respectively, in addition to the previously observed primary and secondary outflows.
while the [Ar II] was not. In this complementary work, we use these lines to address long-debated questions about
These elongated components exhibit Hubble-law like velocity structures, i.e., an increase of velocity with increasing
protoplanetary disk winds regarding their mass-loss rate, the origin of their ionization, and the role of magneticallydistance from the protostar, suggesting that it is the third outflow associated with the protostar. Besides, a new
driven winds as opposed to photoevaporation. To this end, we perform photoionization radiative transfer on simple
redshifted component is detected at radii of ⇠ 4000 -7500 on the northwestern side of the protostar. This redshiftedhydrodynamic wind models to map the line emission. We compare the integrated model luminosities to those observed
component also exhibits a Hubble-law like velocity profile, which could be the counterpart of the secondary outflow
with MIRI-MRS to identify which models most closely reproduce the data and produce synthetic images from these tomostly detected at blueshifted velocities in a previous study. The three outflows are all misaligned by ⇠ 20-90 , andunderstand what information is captured by measurements of the line extents. Along with the low degree of ionization
the dynamical timescale of the primary outflow is shorter than those of the other outflows approximately by an order
implied by the line ratios, the relative compactness of [Ar II] compared to [Ne II] is particularly constraining. Thisof magnitude. These facts hint that the outflow launch direction has significantly changed with time. The outflow
requires Ne II production by hard X-rays and Ar II production by soft X-rays (and/or EUV) in an extended (& 10 au)
direction may change if the rotational axis and the magnetic field are misaligned, or if the dense core is turbulent. We
wind that is shielded from soft X-rays - necessitating a dense wind with material launched on scales down to 1 au.
favor the second scenario as the origin of the multiple outflows in IRAS 15398 3359 based on a comparison between
Such conditions could be produced by photoevaporation, whereas an extended MHD wind producing equal shielding
the observational results and numerical simulations.
would likely underpredict the line fluxes. However, a tenuous inner MHD wind may still contribute to shielding theextended wind. This picture is consistent with constraints from spectrally-resolved line profiles.