SFN #350 13-17
担当：土井 聖明 (総研大D1)

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13. A new planet candidate detected in a dust gap of the disc around HD
163296 through localised kinematic signatures. An observational validation of
the Discmine
14. A population of transition disks around evolved stars: Fingerprints ofplanets? Catalog of disks surrounding Galactic post-AGB binarie
15. Ammonia mapping observations toward the Galactic massive star-forming
region Sh 2-255 and Sh 2-25
16. Dynamics of magnetic ux tubes in accretion disks of Herbig Ae/Be star
17. Breaking Orion’s Veil bubble with fossil out ows

A new planet candidate detected in a dust gap of the disc around HD 163296 throughlocalised kinematic signatures. An observational validation of the Discminer

Andres F. Izquierdo, Stefano Facchini, Giovanni P. Rosotti, Ewine F. van Dishoeck, Leonardo Testi F We report
the robust detection of coherent, localised deviations from Keplerian rotation possibly associated with the presence of two giant
planets embedded in the disc around HD 163296. The analysis is performed using the DISCMINER channel-map modelling
framework on 12 CO J = 2 1 DSHARP data. Not only orbital radius, but also azimuth of the planets are retrieved by ourtechnique. One of the candidate planets, detected at R = 94 ± 6 au, = 50 ± 3 (P94), is near the centre of one of the gaps
in dust continuum emission, and is consistent with a planet mass of 1 MJup . The other planet, located at R = 261 ± 4 au,= 57 ± 1 (P261), is in the region where a velocity kink was previously observed in 12 CO channel maps. Also, we provide asimultaneous description of the height and temperature of the upper and lower emitting surfaces of the disc, and propose theline width as a solid observable to track gas substructure. Using azimuthally averaged line width profiles we detect gas gaps at
R = 38 au, R = 88 au, and R = 136 au, closely matching the location of their dust and kinematical counterparts. Furthermore,
we observe strong azimuthal asymmetries in line widths around the gas gap at R = 88 au, possibly linked to turbulent motions
driven by the P94 planet. Our results confirm that the DISCMINER is capable of finding localised, otherwise unseen velocity
perturbations thanks to its robust statistical framework, but also that it is well suited for studies of the gas properties andvertical structure of protoplanetary discs.

Supplement Series, 257:1 (29pp), 2021 November

A population of transition disks around evolved stars: Fingerprints of planets? Catalog
円盤中での惑星検出に関する論文
of disks surrounding Galactic post-AGB binaries

Jacques163296の円盤で惑星の兆候が見つかった(また)Kluska, Hans Van Winckel, Quentin Coppée, Glenn-Michael Oomen, Devika Kamath, Valentin Bu・HD
jarrabal, Michiel Min F Post-asymptotic giant branch (post-AGB) binaries are surrounded by massive disks of gas and dustthat are similar to protoplanetary disks around young stars. We assembled a catalog of all known Galactic post-AGB binaries
・94
auと261
auにそれぞれ見つかったwith disks. We explore the correlations between the diﬀerent observables with the aim of learning more about potential disk-

binary interactions. We compiled spectral energy distributions of 85 Galactic post-AGB binary systems. We built a color-color
diagram to diﬀerentiate between the diﬀerent disk morphologies traced by the infrared excess. We categorized the diﬀerent
disk types and searched for correlations with other observational characteristics of these systems. Between 8 and 12that is,disks having no or low near-infrared excess. We find a strong link between these transition disks and the depletion of refractoryelements on the surface of the post-AGB star. We interpret this link as evidence of a mechanism that stimulates the dust
and gas separation within the disk and that also produces the transition disk structure. We propose that such a mechanism islikely to be due to a giant planet carving a hole in the disk, eﬀectively trapping the dust in the outer disk parts. We propose
disk evolutionary scenarios, depending on the presence of such a giant planet in the disk. We advocate that giant planets can・この手法からは方位角も分かる

・対応する位置にガスのギャップもある背景
円盤中の惑星は発見が難しい(例: PDS 70 (右上), AB Aur(右下))
惑星が作る円盤中の構造から惑星が間接的に検出されてきた・ダストの構造 (e.g., Isella et al. 2016)
・ガスの構造・密度構造

ALMA プレスリリースより

・速度構造
・公転速度 (Teague et al. 2018)
・鉛直運動 (Teague et al. 2019)
・局所的な摂動 (Pinte et al. 2018)↑今回はこれ
本研究の特徴・惑星の位置(r, phi)が分かる
すばる プレスリリースより

手法
CO (J=2-1)のchannel mapをモデリング・DISKMINER packageを使用
・まずは滑らかな円盤モデル
・ケプラー回転する2次元(r,z)円盤
モデルとの残差を見て惑星を探す
モデルと比較する点・速度のズレ (惑星が作る運動を探す)
・線幅 (惑星が作る面密度ギャップを探す)

Figure 1. Selected channel maps from DSHARP 12CO J = 2–1 data of the HD 163296 disk (top row), compared to those from the best-ﬁt model found by the

結果

The Astrophysical Journal, 928:2 (19pp), 2022 March 20

Izquierdo et al.

・惑星1
r = 94

6 au、φ = 50

3ダスト面密度ギャップに対応
・惑星2
r = 261

4 au、φ = 57

1

Pinte et al. 2018のkinkの再確認
・速度構造のズレから位置が2次元で分かる
・対応する位置の線幅=ガス面密度が低くなってる(確認)Figure 8. Summary of the main results of this work. The green crosses mark the inferred location of the P94 and P261 planets, and the blue–red contours, ranging
from ±0.15 to ±0.30 in steps of 0.05 km s−1, are nearby velocity residuals associated with the detections. The background colors are azimuthally averaged line width
residuals to highlight the location of gas gaps. In light red and blue are overlaid the kinematic ﬁlamentary structures extracted from centroid velocity residuals on theupper surface of the disk. The quarter circle on the right is a zoom-in around the P94 perturbation, whose nearby velocity contours are this time colored according totheir magnitude. The green ellipse centered on the P94 cross indicates the spatial error of the detection.

the channels that cross the δυ ≈ 0.15 km s−1 ﬁlament on theinto account. Both effects strengthen the idea that this localizedA population of transition disks around evolved stars: Fingerprints of planets? Catalog
of disks surrounding Galactic post-AGB binaries

Jacques Kluska, Hans Van Winckel, Quentin Coppée, Glenn-Michael Oomen, Devika Kamath, Valentin Bujarrabal, Michiel Min F Post-asymptotic giant branch (post-AGB) binaries are surrounded by massive disks of gas and dustthat are similar to protoplanetary disks around young stars. We assembled a catalog of all known Galactic post-AGB binaries
with disks. We explore the correlations between the diﬀerent observables with the aim of learning more about potential diskbinary interactions. We compiled spectral energy distributions of 85 Galactic post-AGB binary systems. We built a color-color
diagram to diﬀerentiate between the diﬀerent disk morphologies traced by the infrared excess. We categorized the diﬀerent
disk types and searched for correlations with other observational characteristics of these systems. Between 8 and 12that is,disks having no or low near-infrared excess. We find a strong link between these transition disks and the depletion of refractoryelements on the surface of the post-AGB star. We interpret this link as evidence of a mechanism that stimulates the dust
and gas separation within the disk and that also produces the transition disk structure. We propose that such a mechanism islikely to be due to a giant planet carving a hole in the disk, eﬀectively trapping the dust in the outer disk parts. We propose
disk evolutionary scenarios, depending on the presence of such a giant planet in the disk. We advocate that giant planets can
successfully explain the link between the transition disks and the observed depletion of refractory materials. If the planetaryscenario is confirmed, disks around post-AGB binaries could be a unique laboratory for testing planet-disk interactions andtheir influence on the late evolution of binary stars. The question of whether such planets are first- or second-generation bodies
remains to be considered. We argue that these disks are ideal for studying planet formation in unprecedented parameter space.

post AGB星のbinaryに付随する円盤統計・post AGB星には(原始惑星系円盤のような)円盤が付随している
6

・さまざまな観測から85個のpost AGB星の観測を集めて統計を取る
・8-12%のターゲットは遷移円盤状の円盤、中心星の金属が枯渇している傾向
・惑星によるダストトラップが働いている？

背景
AGB星は大きくなってガスを放出する
ガスの放出に伴って周りにthickな円盤(原始惑星系円盤に近い)を作る
円盤進化と惑星形成を別の視点から捉えられる(原始惑星系)円盤進化の疑問
・円盤進化(散逸)はどのように進むか
full disk → transition disk → 散逸
↑これは必須か?
AGB星の円盤の統計を取って、円盤進化の議論につなげる手法・結果A&A 658, A36 (2022)

85天体のpost AGB binaryを集めてcolor-color diagramから分類
Fig. 5.
Distribution of the targets with respect to the infrared to stellar
横軸MIR(W1-W3) 縦軸NIR(H-Ks)

luminosity ratio that is color-coded. The dashed gray lines represent theboundaries of the object categories.

full disk

Fig. 5. Distribution of the targets with respect to the infrared to stellar
luminosity ratio that is color-coded. The dashed gray lines represent theboundaries of the object categories.

a potential incolors (e.g., W
all the possib
but, rather, tocan populate
observed targ
following parmorphology:
surface densi
density powedisk paramet
large grains, adisk inclinatio
eter in range
Table 2). We tfull disk mod
the color-coloFig. B.1.
5.3. Results

full disk

TDtransition disk

color diagrams for models and targets. Top: positions ofFig. 3. Examples of SEDs of post-AGB binaries. Top panel:Fig. 4. Color-color diagrams for models and targets. Top: positions of
IRAS 08544-4431-like(orange) and AC Her-like (blue)
IRAS 08544-4431. Lower panel: IRAS 18281+2149 (AC Her). Labels
the models of IRAS 08544-4431-like (orange) and AC Her-like (blue)
show the sources of photometric data points (see also Sect. 4). We usedolor-color
diagram.
The dashed
gray
lines
represent
Fig.the
6. Medianinfraredexcessin SEDs.
Solid
themediandisks
in the color-color
diagram.
The
dashedgray linesthe
represent
Fig. 6. Medianinfraredexcessin SEDs.
Solidlines
linesrepresent
represent themedianthese well-studied objects as prototypes for objects where the inner rim
tween thedifferent
categories
defined
in
the
text.
BotSED
category
normalized
at 1atµm.
Theareenveloped
enveloped
boundaries between the different categories defined in the text.
Bot-for each
SED foreach category
normalized
1 µm.
TheSEDs
SEDs areofby
theby
disk starts at sublimation radius (top panel) and objects where
locationsdisksof thecolor-coded
observed disks
color-codedwith their assigned
this inner rim is further out (bottom panel). The wavelength where thean area representing
the 25th-to-75th
percentilesSED
SED ofof thetom:
observed
withtheir assigned
an area representing
the 25th-to-75th
percentiles
ofeacheachcategory.
category.
excess starts to appear is used as observational signature.
categories.
A black
T = 5500
is plotted
illustration to
A black body
ofbodyT = of5500
K is Kplotted
forforillustration
tomimic
mimica stellar
a duststellar

The synthetic
disk paramete(Fig. 4, top)tom). There icover a narrow
and transition
between 0.0 ahave also teston the positio
out the addit
models haveand their mid
it is necessar
flux to modea component
however, thatferometric sa
emission to r
extended com
not incorpora

Fig. 5. Distribution of the targets with respect to the infrared to stellar
luminosity ratio that is color-coded. The dashed gray lines represent theboundaries of the object categories.

結果・結論
金属量と比較
・遷移円盤ほど金属量が枯渇している→ 惑星により中心星への降着が止まっている？
J. Kluska et al.: A population of transition disks around evolved stars

BinaryInner dust rim due todust sublimation

Perturbation by a
substellar companion in
the disk

Not depleted
Gas

Cat.
& Cat. 1
Kluskaet al.:
A0populationof transition disks around evolved stars
Fig. 4. Color-color diagrams for models J.and
targets.
Top:
positionsof[H-Ks] > 0.3 & [Fe/H] > -1
the models of IRAS 08544-4431-like (orange) and AC Her-like (blue)
disks in the color-color diagram. The dashed gray lines represent the Fig. 6. Median infrared excess in SEDs. Solid lines represent the median
Depletedboundaries
between the different categories defined in the text. Bot- SED for each category normalized at 1 µm. The SEDs are enveloped byPlanet?
Gas
Cat.their
2 & Cat.
3
tom: locations of the observed disks color-coded withassigned
an area representing the 25th-to-75th percentiles SED of each category.
[H-Ks] < 0.3 & -3 < [Fe/H]<-1 A black body of T = 5500 K is plotted for illustration to mimic a stellar
categories.
Trapped dust
photosphere.
Not depleted
Gas

Disk evolution
Low density disk?

Debris disk?

Dust

Gas

Cat. 3
inclination there is no obvious differences between
the different[H-Ks] < 0.3 & [Fe/H] > -1
categories (Fig. D.3). It only seems that there is a greater num- 6.5. Depletion tracers
ber of short-period orbits for category 3 than in others. But given
the low number of targets, this needs to be further confirmed. We We investigated whether the chemical depletion observed onCat. 4Gas?
conclude that the disk structure in the dust doessignificantly[H-Ks]not< 0.3& [W1-W3] < 2.3 the surface of post-AGB binaries can be linked to the disk
structure. We selected three depletion tracers: [Fe/H], which is
influence the orbital properties of the binary and vice-versa.

A36, page 8 of 24
Dust
Dynamical
truncation sublimation
radiusradiusRadiusÜ. Kavak et al.: Breaking Orion’s Vei

Breaking Orion’s Veil bubble with fossil outflows

1.5 pc
4 40

150

M43
20

100

Trapezium Stars

Dec (J2000)

Dec (J2000)

5 00

Tmb dv [K km s 1 ]200

NGC 1977rBa

Anisotropic Infall and Substructure formation in Embedded Disks

250

n
rio
O

U Kavak, J. R. Goicoechea, C. H. M. Pabst, J. Bally, F. F. S. van der Tak, A. G. G. M. Tielens F The roleof feedback in the self-regulation of star formation is a fundamental question in astrophysics. The Orion Nebula is the nearest
site of ongoing and recent massive star formation. It is a unique laboratory for the study of stellar feedback. Recent SOFIA[CII] 158 µm observations revealed an expanding bubble, the Veil shell, being powered by stellar winds and ionization feedback.
We have identified a protrusion-like substructure in the Northwest portion of the Orion Veil Shell that may indicate additional
feedback mechanisms that are highly directional. Our goal is to investigate the origin of the protrusion by quantifying its
possible driving mechanisms. We use the [CII] 158 µm map of the Orion Nebula obtained with the upGREAT instrument
onboard SOFIA. The spectral and spatial resolution of the observations are 0.3 km/s and 16 arcsec, respectively. We consider
three possible origins for this protrusion: Fossil outflow cavities created by jets/outflows during the protostellar accretion phase,pre-existing clumpiness in the OMC-1 core, and the stellar wind during the main sequence phase. Based on the energetics andthe morphology, we conclude that the northwestern part of the pre-existing cloud was locally perturbed by outflows ejected frommassive protostars in the Trapezium cluster. This suggests that the protrusion of the Veil is the result of mechanical rather
than radiative feedback. Furthermore, we argue that the location of the protrusion is a suitable place to break the Orion Veilowing to the photo-ablation from the walls of the protrusion. We conclude that the outflows of massive protostars can influence
the morphology of the future HII,region and even cause breakages in the ionization front. Specifically, the interaction of stellar
winds of main-sequence stars with the molecular core pre-processed by the protostellar jet is important.

40

50

M42

Aleksandra Kuznetsova, Jaehan Bae, Lee Hartmann, Mordecai-Mark Mac Low F The filamentary nature of accretion streams found around embedded sources suggest that protostellar disks experience heterogenous infall from the star-forming0
environment, consistent with the accretion behavior onto star-forming cores in top-down star-cluster formation simulations. This
Ü. Kavaket al.: Breaking
Orion’s Veil bubble
with fossil outflows
h
m
m
m
m
m
5 37
36
35
34
33
may produce disk substructures in the form of rings, gaps, and spirals continuing to be identified by high-resolution imaging
RA (J2000)
surveys in both embedded Class 0/I and later Class II sources. We present a parameter study of anisotropic infall, informedby the properties of accretion flows onto protostellar cores in numerical simulations, and varying the relative specific angular
Outflow-1
1
momentum of incoming flows as well as their flow geometry. Our results show that anisotropic infall perturbs the disk andFig. 1. Left: The integrated (between 5 and +14 km s ) intensity [C ii] 158
on board SOFIA. The positions of NGC 1977, Trapezium stars, M42, M43, an
readily launches the Rossby wave instability (RWI). It forms vortices at the inner and outer edge of the infall zone where
Outflow-2
region from the map including the area of interest for this study,
the protrusionmaterial is deposited. These vortices drive spiral waves and angular momentum transport, with some models able to driveis the edge of the expanding Veil shell. Faint emission extends well beyond th
2
stresses corresponding to a viscosity parameter on the order of ↵ ⇠ 10 . The resulting azimuthal shear forms robust pressure
Section 3 for more detail about the kinematics and componentsof the protrus
Outflow-3

オリオンのbubble veilの構造にある突起部の論文
・オリオンにあるexpanding bubbleをいろんな観測(後述)で調べた

・bubbleの西側にある突起の要因を調べる
7

・過去の大質量星形成期に吹いたout owによるものか

Trapezium
Stars

Shell in Spitzer 8 µm emission
SPIRE (250, 350, and 500 µm), Firstandimages.
In this study, we investigate the origin of the protrusion
Redshifted
Kelvin-Helmholtz
Lobe velocity-resolved SOFIA [C ii]
using
maps and compare them toInstabilities
the dust, CO and PAH emission. Finally, we use
the energetics
West Rimof the protrusion to assess the driving mechanism.
We organize the paper as follows. In Section 2 we describe
East Rim 12
the observations of [Cii], CO, and 13 CO as well as dust emission. In Section 3 we derive observational results on the general
O

rio
n

Ba

r

O
ex riontens Bario ’snflProtrusion(Second Shell)

bo
C+
arr
wa
wi
ray
1.8
14

背景・観測設定
大質量星の星間ガスへのフィードバックは星形成に大きな影響
bubbleや周囲を観測観測装置、波長、観測対称・SOFIA, 158 um=[CII]輝線 ← 分子が乖離する領域を観測するのに必要
・IRAM, 1.3 mm=12CO, 13CO ← 分子ガス
・ESO/MPI 2.2m鏡, 656 nm=Hα ← 電離ガス
・Hershel, 70-500 um ← ダスト熱放射
・Spitzer, 8um ← FUVに照らされるPDR表面A&A proofs: manuscript no. aanda

200

5 00

10
Dec (J2000)

突起部のPV図から運動を推定
・6 km/sと12 km/sのblue shift成分がある

1

2

3

4

5

6

9
8
7

150
125
100

30
29
28
27
26
25
24

20

bubbleの広がる速度(13 km/s)より遅い

75
50

23

22
21
20
19
18
17
16

30

過去(星形成段階)に吹いたout owによるもの
降着円盤を通したou owを通した大質量星形成が起きていたか

5h35m00s

34m30sTmb dv [K km s 1 ]

結果・議論

175

15
14
13
12
11
10

25
00s

33m30s00s

0

RA (J2000)

Ü. Kavak et al.: Breaking Orion’s Veil bubble with fossil outflows

8400.00 600.00 800.00
Offset [arcsec]

1000.00r

Kelvin-Helmholtz
Instabilities
West Rim6

10.0

ciated with structures deeper in OMC 1 that are not exposed to
FUV radiation.

0.0

In contrast, the [C ii] line shows a di↵erent behavior than CO,with the exception of position 2. In addition to the OMC, whichemits predominantly at VLSR = +9 km s 1 (i.e., red-dotted line in
Fig. 4), we identify two other components on the [C ii] emission.
To investigate the origin of these components, we have integrated the [C ii] emission between 5 and +3 km s 1 (blue is-10.0

East Rim

0.00

Article number, page 6 of 20
fl

0
8

20.0

Ba

O
ex riontens Bar
io ’s
n

ffl

200.002

200.00400.00Tmb [K]

Redshifted
Lobe

rio
n

Cut 8

Fig. 3. Top: Selected crosscuts along the green arrows are overlaid on the integrated [C ii] intensity map. The number of the crosscuts is indicatedat the starting point of the cut. Bottom: The middle and bottom panels show the pv diagram generated along the magenta crosscuts (cuts 8 and23, respectively). The pv diagram with horizontal green lines in both panels show the [C ii] emission produced by the FUV-illuminated surfaceof OMC and the arcuate white and yellow lines trace the shell expanding at 12 km s 1 and 6 km s 1 , respectively. The remaining pv diagrams in
Fig. B.9 and B.10 have the same scale in both axes. A 12 CO-PV diagram along the crosscut 23 is shown in Fig. B.8 for comparison with [C ii].

Vlsr [km/s]

O

4

0.0

0.00

Protrusion(Second Shell)First Shell

10.0

-10.0

Outflow-3
TrapeziumStars

6
Tmb [K]

Outflow-2

Vlsr [km/s]

Outflow-1

20.0

first component), +3 and +12 km s 1 (green is second component or OMC itself), and +12 and +15 km s 1 (red is third
component). Note that the first component shifts to somewhat
higher and lower velocities and that part of the profile of the firstemission structure may be confused by emission of the OMC 1
core surface that dominates the total emission. We are therefore not able to use a fixed integration range for this component.
The integration range is assumed based on positions 1 and 12 in

600.004

Cut 23800.001000.00

20

Ammonia mapping observations toward the Galactic massive star-forming region Sh
2-255 and Sh 2-257

Mikito Kohno, Toshihiro Omodaka, Toshihiro Handa, James O. Chibueze, Takumi Nagayama, Ross A. Burns,
Takeru Murase, Ren Matsusaka, Makoto Nakano, Kazuyoshi Sunada, Rin I. Yamada, John H. Bieging F We
performed NH3 (J, K) = (1, 1), (2, 2), and (3, 3) mapping observations toward the Galactic massive star-forming region Sh 2-255
and Sh 2-257 using the Nobeyama 45-m telescope as a part of the KAGONMA (KAgoshima Galactic Object survey with theNobeyama 45-metre telescope by Mapping in Ammonia lines) project. NH3 (1,1) has an intensity peak at the cluster S255 N, is
distributed over 3 pc ⇥ 2 pc and is located between two HII regions. The kinetic temperature derived from the NH3 (2, 2)/(1, 1)
ratio was ⇠ 35 K near the massive cluster S255 IR. These clusters also show emission with a large line width of ⇠ 3-4 km
s 1 . Based on the reported data we suggest that NH3 gas in these regions is aﬀected by stellar feedback from embedded YSO
clusters in S255 IR and S255 N. We also detected NH3 (1,1) emission in a region west of the main gas clump at the location ofa concentration of Class II YSOs adjacent to the HII regions Sh 2-254. The presence of Class II YSOs implies ⇠ 2 Myr of starformation, younger than Sh 2-254 (⇠ 5 Myr), thus we suggest that star formation in the western region could be influenced by
the older HII region Sh 2-254.

Dynamics of magnetic
flux tubes in accretion disks of Herbig Ae/Be stars
野辺山45mを使用した大質量星形成領域のNH3観測
Sergey A. Khaibrakhmanov, Alexander E. Dudorov F The dynamics of magnetic flux tubes (MFTs) in the accretion

disk of typical Herbig Ae/Be star with fossil
large-scale
magnetic field is modeled taking into
the buoyant and drag(a) NH
NH3 (2,2)(b)account
3 (J,K)=(1,1)
forces, radiative heat exchange with the surrounding gas, and the magnetic fieldof the disk. The structure of the disk isNsimulated using our magnetohydrodynamic (MHD) model, taking into account the heating of the surface layers of the disk withthe stellar radiation. The simulations show that MFTs periodically rise from the innermost region of the disk with speeds up
W
B actionto 10 12 km s 1 . MFTs experience decaying magnetic oscillations under theof the external magnetic field near the
disk’s surface. The oscillation period increases with distance from the star and initial plasma beta of the MFT, ranging fromseveral hours at r = 0.012 au up to several months at r = 1 au.
A The oscillations are characterized by pulsations of the MFT’s
characteristics including its temperature. We argue that the oscillations can produce observed IR-variability of Herbig Ae/Bestars, which would be more intense than in the case of T Tauri stars, since the disks of Herbig Ae/Be stars are hotter, denser
and have stronger magnetic field.

Breaking Orion’s Veil bubble with fossil outflows

U Kavak, J. R. Goicoechea, C. H. M. Pabst, J. Bally, F. F. S. van der Tak, A. G. G. M. Tielens F The roleof feedback in the self-regulation of star formation is a fundamental question in astrophysics. The Orion Nebula is the nearest
site of ongoing and recent massive star formation. It is a unique laboratory for the study of stellar feedback. Recent SOFIA
C the Veil shell, being powered by stellar winds and ionization feedback.
[CII] 158 µm observations revealed an expanding bubble,
We have identified a protrusion-like substructure in the Northwest portion of the Orion Veil Shell that may indicate additional
feedback mechanisms that are highly directional. Our goal is to investigate the origin of the protrusion by quantifying its
possible driving mechanisms. We use the [CII] 158 µm map of the Orion Nebula obtained with the upGREAT instrument
onboard SOFIA. The spectral and spatial resolution of the observations are 0.3 km/s and 16 arcsec, respectively. We consider
three possible origins for this protrusion: Fossil outflow cavities created by jets/outflows during the protostellar accretion phase,pre-existing clumpiness in the OMC-1 core, and the stellar wind during the main sequence phase. Based on the energetics andthe morphology, we conclude that the northwestern part of the pre-existing cloud was locally perturbed by outflows ejected from(c) NH3 (3,3)
NN

W 2-257. Blue, green
W Fig. 1. (a) Three color composite image of Sh 2-255 and Sh

respectively. (b) 12 CO J =2-1 integrated intensity map obtained by Bieging et alcluster S255 IR and S255 N, respectively. The yellow boxes show the NH3 mappin
size of H II regions are obtained from Mizuno (1982) and Chavarrı́a et al. (2008).

massive proto-cluster (Cyganowski et al. 2007; Zeml

Recently, high-resolution (∼ 0.1 pc scale) o

clouds were carried out using radio interferometers (eNH3 mapping observations (∼ 10 pc scale) aiming t

interactions in high-mass star formation remain limite

the interaction between H II regions and molecular clping observations toward the Sh 2-255 and Sh 2-257

the older HII region Sh 2-254.

Dynamics of magnetic flux tubes in accretion disks of Herbig Ae/Be stars

Sergey A. Khaibrakhmanov, Alexander E. Dudorov F The dynamics of magnetic flux tubes (MFTs) in the accretion
disk of typical Herbig Ae/Be star with fossil large-scale magnetic field is modeled taking into account the buoyant and dragforces, radiative heat exchange with the surrounding gas, and the magnetic field of the disk. The structure of the disk issimulated using our magnetohydrodynamic (MHD) model, taking into account the heating of the surface layers of the disk withthe stellar radiation. The simulations show that MFTs periodically rise from the innermost region of the disk with speeds up
to 10 12 km s 1 . MFTs experience decaying magnetic oscillations under the action of the external magnetic field near the
disk’s surface. The oscillation period increases with distance from the star and initial plasma beta of the MFT, ranging fromseveral hours at r = 0.012 au up to several months at r = 1 au. The oscillations are characterized by pulsations of the MFT’s
characteristics including its temperature. We argue that the oscillations can produce observed IR-variability of Herbig Ae/Bestars, which would be more intense than in the case of T Tauri stars, since the disks of Herbig Ae/Be stars are hotter, denser
and have stronger magnetic field.

Breaking Orion’s Veil bubble with fossil outflows

U Kavak, J. R. Goicoechea, C. H. M. Pabst, J. Bally, F. F. S. van der Tak, A. G. G. M. Tielens F The roleof feedback in the self-regulation of star formation is a fundamental question in astrophysics. The Orion Nebula is the nearest
site of ongoing and recent massive star formation. It is a unique laboratory for the study of stellar feedback. Recent SOFIA[CII] 158 µm observations revealed an expanding bubble, the Veil shell, being powered by stellar winds and ionization feedback.
We have identified a protrusion-like substructure in the Northwest portion of the Orion Veil Shell that may indicate additional
feedback mechanisms that are highly directional. Our goal is to investigate the origin of the protrusion by quantifying its
possible driving mechanisms. We use the [CII] 158 µm map of the Orion Nebula obtained with the upGREAT instrument
onboard SOFIA. The spectral and spatial resolution of the observations are 0.3 km/s and 16 arcsec, respectively. We consider
three possible origins for this protrusion: Fossil outflow cavities created by jets/outflows during the protostellar accretion phase,pre-existing clumpiness in the OMC-1 core, and the stellar wind during the main sequence phase. Based on the energetics andthe morphology, we conclude that the northwestern part of the pre-existing cloud was locally perturbed by outflows ejected frommassive protostars in the Trapezium cluster. This suggests that the protrusion of the Veil is the result of mechanical rather
than radiative feedback. Furthermore, we argue that the location of the protrusion is a suitable place to break the Orion Veilowing to the photo-ablation from the walls of the protrusion. We conclude that the outflows of massive protostars can influence
the morphology of the future HII,region and even cause breakages in the ionization front. Specifically, the interaction of stellar
winds of main-sequence stars with the molecular core pre-processed by the protostellar jet is important.

Anisotropic Infall and Substructure formation in Embedded Disks

Aleksandra Kuznetsova, Jaehan Bae, Lee Hartmann, Mordecai-Mark Mac Low F The filamentary nature of accre-