星形成ゼミ

楠根貴成（国立天文台）

The star formation newsletter No.322

56. Illuminating the Tadpoleʼs metamorphosis I: MUSE observations of a small globule in asea of ionizing photons
57. Laser experiment for the study of accretion dynamics of Young Stellar Objects: designand scaling
58. CHIMPS: Physical properties of molecular clumps across the inner Galaxy
59. Investigating the nature of the extended structure around the Herbig star RCrA using
integral ﬁeld and high-resolution spectroscopy
60. Weak and Compact Radio Emission in Early High-Mass Star Forming Regions: II. The
Nature of the Radio Sources
61. Dust Polarization Toward Embedded Protostars in Ophiuchus with ALMA. III. Survey
Overview
62. Global 3D radiation-hydrodynamic simulations of gas accretion: The opacity dependent
growth of Saturn-mass planets
63. Complex Organic Molecules in Star-Forming Regions of the Magellanic Clouds
64. Modeling deuterium chemistry in starless cores: full scrambling versus proton hop
65. Using Herschel and Planck observations to delineate the role of magnetic ﬁelds inmolecular cloud structuredpole globule and the HH 900 jet+outflow system ([S ii]=red, H↵=green, [O iii]=blue). A
http://arxiv.org/pdf/1909.02079
rojet that lie projected
onto the western limn of HH 900 are labeled. Right: Three-color image
t+outflow system: the molecular outflow ([C i]=red), the atomic jet ([Fe ii]=green), and the56. Illuminating the Tadpoleʼs metamorphosis I: MUSE observations of a small globule in asea of ionizing photons

Illuminating the Tadpole’s metamorphosis I: MUSE observations of a small globule ina sea of ionizing photons

1
2,3
ReiterAnna
F. McLeod,for
PamelaD.elements
Klaassen1 , Andrés E. Guzmán4 , J.E. Dale5 , Joseph C.
The integration Megan
time
Table, 1.
Ionization
potentials
detected
6
7
Mottram and Guido Garay
al on-source integra1
in the ESO esorex
UK Astronomy Technology Centre, ROE, Blackford Hill, Edinburgh, EH9 3HJ, UK; 2 Department of Astronomy,
eilbacher et al. 2012)
University of California Berkeley,94720, USA; 3 Department of Physics and Astronomy, Texas Tech
NameBerkeley,first CA
second(eV)79409,(eV)
University, PO Box 41051, Lubbock, TX
USA; 4 National Astronomical Observatory of Japan, 2-21-1 OsUSE spectra showedawa, Mitaka, Tokyo 181-8588, Japan; 5 Centre for Astrophysics Research, University of Hertfordshire, College Lane,
TadpoleH
13.6—
Tadpolemetamorphasis
metamorphasis 55
me of the wavelength
Hatfield, AL10 9AB, UK; 6 Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; 7
He
24.6
54.4
Departamentode Astronoma, Universidad
de Chile,
Camino el Observatorio 1515, Las Condes, Santiago, Chile
his would result
in
C
11.3
24.4
ps of emission E-maillines contact: megan.reiter at stfc.ac.uk
N
14.5
29.6
., H , He I 4921,
O
13.6
35.1
We present new MUSE/VLT observationsof a small
globule in the Carina H ii region that hosts the HH 900 jet+outflow
emission line ratios.
S
10.4
23.3
system. Data were obtained with the GALACSI ground-layer adaptive optics system in wide-field mode, providing
y-pixel continuum fit
Cl
13.0
23.8
spatially-resolved maps of diagnostic emission lines. These allow us to measure the variation of the physical properties
Ar
15.8
27.6
he lunar and stellar
Tadpole metamorphasis
3in the globule and jet+outflow system.
Wefind high temperatures(Te ≈ 104 K), modest
extinction (AV ≈ 2.5 mag),Ca
6.1 −3 11.9
esulting continuumand modest electron densities (neFe≈ 2007.9cm ) intheionizedgas.
Higherexcitation
lines
trace the ionized outflow;
16.2
r analyses discussed
both the excitation and ionizationNiin the7.6outflow18.2
increase with distance from the opaque globule. In contrast, lower
4−3
excitation lines that are collisionally de-excited at densities >∼10 cm trace the highly collimated protostellar jet.
Assuming the globule is an isothermal sphere confined by the pressure of the ionization front, we compute a BonnorEbert mass of ∼ 3.7 M⊙ . This is two orders of magnitude higher than previous mass estimates, calling into question
gas globules
like [Fe likeii], [Caii], and [Niii] tracetothe
bipowhether small
the Tadpole
contribute
thecollimatedbottom of the
IMF. Derived globule properties are consistentlarthatjet hasthatbeen
threads
the center byof thethe ionization
wide-angle
with a cloud
and/orthroughwill be compressed
front on its surface. At the estimated globule−7 Reiter−1et al. 2015a). The spectral
outflowrate(seeofFigure
1 andphotoevaporation
∼
5
×
10
M
,
the
globulewillbecompletely
ablated in ∼ 7 Myr. Stars that form in⊙ yr
USE, with more thanresolutionof MUSE
allowsinto
us tovelocitydi↵erences
globules likethe Tadpole
will emerge
theresolve
H ii laterand may
help resolve some of the temporal tension between
and forbidden emis& and
50 km
s 1 , enabling a kinematic analysis of the faster pordisk survival
enrichment.
atoms. A full list oftions
ofMUSE
theimage
jet+outflow
system.
In 900thefollowing
sections,
we [O iii]=blue). A
Figure1. Left:of the Tadpole globuleand the HH
jet+outflow
system ([Sii]=red, H↵=green,
Acceptedby
MNRAS
n Table A1. Detected
second YSO (PCYC 838) and possible microjet that lie projected onto the western limn of HH 900 are labeled. Right: Three-color image
derivethephysicalproperties
ofmolecular
the tadpole-shaped
globulehighlightingdi↵erent
componentsof the jet+outflow
system: theoutflow ([C i]=red), the atomicjet ([Fe ii]=green), and theion states in thehttps://arxiv.org/pdf/1909.12666
gas, ionized outflow ([O i]=blue).
and the HH 900 jet+outflow system.
potentials . 13.6 eV
Table 1. Ionization potentials for detected elements
nd ionization poten- posure to reduce instrument artifacts. The integration timefor each exposure was 240 s, for a total on-source integraLaser
experiment
for the study of accretion dynamics of Young Stellar Objects: design
time of 720 s. Data were reduced in the ESO esorex
f is generally seenin tionenvironment
MUSE pipeline (Weilbacher
et al. 2012)
Name
first
secondand scaling
3.1 of theExtinction/ Reddening
ackground. Emission
using standard calibrations.
(eV)
(eV)
1,2 to lunar contamination,
3 the MUSE spectra4 showed
55Due
G. Revet
,
B.
Khiar
,
J.
Béard,R.
Bonito,S.
Orlando,—M.V. Starodubtsev2 , A. Ciardi6 and J.
the ionization front
H
13.6
We
use
the
Balmerincreased
fluxestowards
theblue regimedecrementof the wavelength to estimate the line-of-sight
He
24.6
54.4
coverage with respect to the red. This would result inFuchs1,2,7
ially resolved MUSE
C
11.3
24.4
as
falselyextinction
high fluxes of integrated
maps of emission lines
N
14.5
29.6
nes, we measure1 thethatportion Écoleof the spectrum(e.g., H , He I CEA:
4921,
O
13.6
35.1 UPMC Univ Paris 06: Sorbonne Universités
LULI in
CNRS,
Polytechnique,
Université Paris-Saclay; 10.4
4
M.
Reiteretemission
al. 2line ratios.
[O iii] 4959,5007) leading to erroneousS
23.3
the ionization frontE(HH↵) continuum
2.5of Applied ClPhysics,(H↵/H- F-91128
Palaiseaucedex,
France;Institute46)intUlyanov Street, 603950 Nizhny Novgorod,
We correct
this by performinga pixel-by-pixel
fit
13.0
23.8
E(B V) = removes both the lunar and= stellar⇥log10Ar
15.8
27.6
3 subtraction, which (Hy irradiated HHRussia;
900 and
)
(H↵)
(H
)
(H↵)
)
Flash
Centerfor
Computational
Science,
Department
Astronomy& [FeAstrophysics,
Universityof
Ca (H↵/H
6.1 of 11.9
obs
continuasimultaneously.
We
use
the
resultingcontinuum1.257 (Fitzpatrick4 1999), this becomesnear-IRii] emission.The
Reiteret al. (2015a)
argue that
Fe
7.9
16.2
5
cube to performthe nebular
analyses discussed
Chicago,subtracted
IL, UnitedStates;LNCMI,UPR 3228, CNRS-UGA-UPS-INSA,
31400
Toulouse,
France;
INAF(Istituto
4 cm 3 ) are required to
Ni
7.6
18.2
(1) highdensities
in
the
jet
core
(&
10
in this paper.
6
2.86
bright in the globule
Nazionale diAstrofisica)- Osservatorio
Astronomico di Palermo, (2)Palermo,shield
Italy;theLERMA,de Paris,
Fe+ fromObservatoire
further ionization.
Nisini et al. (2002,
E(BV) = 1.99⇥ log107(H↵/H
gle outflow originallywhere( ) is thevalueof the )extinction
at[NiUniv.
aii] trace
given
PSL Research
University,
CNRS,
Sorbonne
University,
UPMC
Paris
06,bipoF-75005,
Paris,
France;obs
gas like [Fe ii],curve[Caii], andthecollimated
2005)
also
derivedsmaller
electronELI-NP,
densities
from
[S
ii]
FigureA
image
showingthe
theslices
slicesthroughthroughthe
theglobule
globuleparallel
parallelandandperpendicularperpendiculartotothe
thejet+outflow.
jet+outflow.We
Weplotplotthethevariation
variation
Figure2.2.Athe[S[Sii]ii]image
showinglar
jetNuclearthat threadsEngineering,
throughthe2013).
center 30of thewide-angle
3 RESULTS
alongthethejet+outflow
jet+outflow(red(redline;line;plots
plotsshown
shownononthe
theleft)left)and
andperpendicularperpendiculartotoitit(blue(bluedotted
dottedline;
line;plots
plotsshown
shownononthe
theright)
right)ofofthe
the
along
“Horia Hulubei”
InstituteforPhysics
Reactorului
Street,RO-077125,
Bucharestrom HST. Forbidden
wavelength(see
the Appendix
ofand
Momcheva
etal.withcomparedto those
determinedfrom thenear-IR[Fe
ii]
whereNational
we haveassumedCase
B recombinationforgas
outflow (see Figure
1 andReiteret al. 2015a). lines
The spectral
following
physicalparameters(see
Sections
3.1
and
3.2):
(a)
A
;
(b)
n
;
(c)
T
;
(d)
the
degreeofionizationas
traced
by
theHe
Hei i
e
e
V
following physical parameters (see Sections 3.1 and 3.2): (a) AV ; (b) ne ; (c) Te ; (d) the degree of ionization as traced by the
We detect ⇠ 50 emission lines with MUSE, with more than
6678
Å
/ ([S
ii] 6717
6717+6731/2)
6731/2)ratio
ratio(black(blackline)line)andandthethe[S[Siii]iii] 9068
9068/ /[S[Sii]ii] 6717
6717ratio
ratio(gray(graydotted
dottedline).
line).Vertical
Verticaldasheddashedgray
graylines
lines
resolution of MUSE
allowsus(H↵)
to resolve =velocity di↵erences
4
2
3
Magurele,
Romaniacited in high-density
Assuming
typicalMilky
Wayextinction,
(H
)
6678
Å
/
([S
ii]
+
lines. Bautista et al. (1994) argue that the optical [Fe ii]
T hydrogen= 10 recombination
K and nelines= and10forbidden
cm emisfor which we
expect an ina dozen
1

天体：

Tadpole globule ＆ HH 900 jet+outﬂow @ Carina Nebula

観測：

AO-assisted MUSE

MUSEの広いスペクトルレンジによって、・物理パラメータの変化を、系での位置の関数として見ることが可能

電離ガスに対してsensitiveなトレーサーを使ったところ、減光量はAv~2.5 magと測定& 50 km s , enabling a kinematic analysis of the faster por-

show
the
approximate
positionofofthe
theglobule
globuleedges.
edges.
showtheapproximate
positiontions of the jet+outflow
In the followinglines
sections,reveal
weeven higher densities, originating from regions
trinsicguilhem.revet
flux
ratio (H↵/H)A1.
= 2.86 (Osterbrock& system.
FerlandE-mail contact:
u-bordeaux.fr
intDetectedlines detected with
MUSE is presented atin Tablederive the physical properties of the tadpole-shaped globuleemissionlines represent
ionization
statesratio
in the gas,with ne ⇡ 105 107 cm 3 . We detect multiple [Fe ii] emission
2006).
The multiple
observed
flux
in andthe Tadpole
and aroundthe HH 900 jet+outflow
system.
A new experimental
designedinvestigate
the accretion dynamics in newly born stars is presented. It takes
although the majorityset-up
have ionization
potentials to. 13.6eVlines in the MUSE data (see Table A1); all trace the same
globuleareionization(H↵/H)obs ⇡ 4.6 6.4, correspond(see Table
for aandlist of outflow
first and second
potenadvantage
a 1tadpole-shaped
magnetically
produced by coupling a laser-generated expanding plasma to a 2×105 G
tials).ofThe
globulecollimateditself is generallystream
seen incollimated morphology seen in the near-IR. Using diagnostic
ing
to
E(B
V)
⇡
0.4
0.7.
To
convertthecolor
excesstoan
3.1
Extinction/
Reddeningsilhouette againstapplied
the bright nebular
background.
Emission(20 T ) externallymagnetic
field.
The stream is used as the accretion column and is launched onto an obstaclelines extinction,
like H↵, [N ii], andii] trace thewe findthat
thewe[Sadopt
RVionization= 4.4 ±front
0.2 (Hur2012),
which
000,
1–18
(2019)We useettheal.
Balmerdecrement
to estimate thediagramsline-of-sight from Bautista & Pradhan (1998),MNRAS
1–18(2019)
target that
theWithstellar
surface.
hasas been used to investigate
in details the accretion dynamics, as MNRAS000,
on the mimics
globule surface.
these spatiallyresolved This
MUSE setup
extinction
ratio [Fe ii] 7155/ 8617 suggests ne > 104 cm 3 , provided
gives of2.4. AVemission. 2.8lines,mag,with athemedianAV ⇡ 2.5 mag. The
observations
diagnostic
we measurevariationin the physicalconditions in is
the slightly
ionization frontE(H RH↵)= 4.8, as
2.5
(H↵/H
)int
that
photoexcitation
also contributes to the emission. Linesestimated
extinction
higherE(Bif V)
we= use⇥log10V =both in the globule and the externally irradiated HH 900
(H ) (H↵) (H ) (H↵)(H↵/H )obs
with lower
criticaldensities,
like the classic nebular tracers
othersystem.
authors have found for Carina (e.g., Smith 40
1987, 2002).
jet+outflow(1)
Many of the emission lines that are bright in the globuleusedto estimate the temperature and density of the ionizedThe
we outflow
estimateusing where
the Balmer
decrement
ionization front
alsoextinction
trace the wide-angle
originally( ) is the valueof the extinction curve
at a given
discoveredH↵ images
HST.estimatedForbidden
wavelength(seeettheal.
Appendixof Momcheva outflow,
et al. 2013). will be de-excited in regions with such high densiis ⇠ in2narrowband
mag lower
thanfrom
thatby
Reiter(2015a)globuleでもjet+outﬂow系でも、高密度（ne ~ 200 cm-3）・高温度（Te ~ 10^4 K）
sion lines from at least seven di↵erent atoms. A full list of

Tadpole globuleからの距離に比例して、outﬂowの励起と電離度は明らかに増加tively). This leads to a corresponding reduction in theted photoevaporation rate, ⇠ 5 ⇥ 10 7 M yr 1 , and
原子輝線： globuleからの距離が増えるにつれousﬂowの励起が変化することが明らかに
e in theestimated globule lifetime.
t the same time, the structure of the wide-angle outmerging from the Tadpole demonstrates that signifimass may be lost to jet entrainment. The outflow is
globuleに近いinner
outﬂowで、[C I] 8727Åを検出
the same width as the globule itself with dusty
fila（イオン化ガスをトレース）
extending into the outflow from the western edgeofobule (Smith et al. 2010). The mass-loss rate in theoutﬂowにおいて、[O III]や[S III]のような高い励起線
d outflow is comparable to the photoevaporation rate,
での吸収： ダストの存在を示唆
7 M yr 1 (from Smith et al. 2010;weow ⇠ 6 ⇥ 10
hat the lower outflow velocity measured by Reiter et al.
=> HH 900 outﬂowは完全にイオン化していないこと
is o↵set by the higher density we measure with thedata in Section 3.2). However, this mass-loss rateを示唆
isr limit as it only accounts for the ionized gas and does
clude the partially ionized gas traced by [C i] and H2
HH 900 outﬂowを通り抜けるcollimated jetが、高密度トレーサーで見える：
molecules or dust in the outflow (see Section 4 andjet中の密度： Reiter+15aで見積もられたものよりもオーダーで高いかも
et al. 2015a, Paper II).
is difficult to constrain how much mass-loss from
12jet M. Reiter et al.
nment contributes to destruction of the globule, given
12 jet（だけ。outﬂowは含まず）の力学エネルギー：
M. nature
Reiter etme-variableof al.
accretion and outflow as wellasdensities
in the jet (see Section 4.1). Assuming the Tad
3 GMcertainties
in the entrainment efficiency. As a roughH ii region
Tadpoleの重力結合エネルギーの３倍以内
the(similar
gravitationalbindingenergyduring
U = thedensities
in the jet (see Section 4.1). Assuming the Tadpoleis a sphere,
to the proplyds
in Orion)
5 R
2 to thete,iswecomparethekinetic
energy
of
the
jet
43
3
G
M
supernova
era inusing
Carina.
a sphere, the gravitational binding energy U = 5 R isU ⇡ 6⇥ 10 erg
MBE estimated in Section 6.2.
The Tadpole is one of the largest objects in the Grenational
the globule. HH 900 is one ofU ⇡ 6binding⇥ 1043 ergenergy
using Mof
BE estimated in Section 6.2. Thekinetic energy of the jet alone is within a factor of 3 o(2014) catalog in both its physical extent andenergyof 900のエネルギー
thejet alone iswithina factorof 343oferg
thegravitational
st kinetic
energeticjets
in Carina,
withE&
1.5⇥10(Re-man & Gahm
HHbindingenergywhatof theglobule.
The globsimil
estimated mass. It is unclear
fractionof the othergravitationalbindingenergyoftheglobule.
The
similarity
al. 2017b), and likely higher given evidence for higher
6

M. Reiter et al.

Figure 3. Emission line intensity tracings parallel (left) and perpendicular (right) to the HH 900 jet+outflow system. Cuts are made at
the same locations shown in Figure 2. We have added a small o↵set to the normalized intensity; horizontal gray dotted lines indicate themean flux level. Vertical dashed gray lines shown the approximate edges of the globule.

NGC 1976, near the Trapezium). Typical ratios are lower in
the nebular gas surrounding the Tadpole (⇠ 0.24) and lower
still in the globule and outflow (⇠ 0.20). There is a clear
trend of increasing ionization with distance from the centerof the globule. In both tracers, the ratio at the terminus of
the contiguous outflow is ⇠ 1.5⇥ greater than the ratio measured in the least ionized gas in and immediately around theglobule (see Figure 2).
Most of the lines that we detect in the outflow haveionization potentials < 13.6 eV; emission lines from more
highly ionized elements requiring more energetic photons are
significantly fainter. Notable exceptions to this trend are: (1)Neutral carbon, [C i] 8727, which is significantly brighter
than the possible C ii 6578 line, despite the fact that theionization potential of C is 11.3 eV. Both lines are seen onlyin the immediate vicinity of the globule. (2) Highly ionizedlines like [S iii] and [Ar iii], are seen in the entire outflow

and both bow shocks. Both require photon energies > 20 eV
to achieve the second ionization, although we do not detect
lines like He+ that also have ionization potentials in thisrange. (3) The detection of [N ii] but not [N i], even though
the ionization potential of N is 14.534 eV.

We can simultaneously compare ionization and shock
excitation in the gas using the diagnostic diagram shownin Figure 4. More highly ionized gas will have smaller[O ii]/[O iii] ratios; shock excitation will enhance the ratio S23 = ([S ii] 6717+ [S ii] 6731+ [S iii] 9068) / H . We
plot the line ratio measured in individual pixels in Figure 4
using separate colors to distinguish between di↵erent components of the system. Points in the Tadpole system occupy
a smaller portion of parameter space than sampled in theOrion Nebula Cluster (the ONC, see Mc Leod et al. 2016).
The most highly ionized gas in this study overlaps with thelower excitation proplyds in Mc Leod et al. (2016). At the
MNRAS 000, 1–18 (2019)

Figure 3. Emission line intensity tracings parallel (left) and perpendicular (right) to the HH 900 jet+outflow system. Cuts are made at
the same locations shown in Figure 2. We have added a small o↵set to the normalized intensity; horizontal gray dotted lines indicate themean flux level. Vertical dashed gray lines shown the approximate edges of the globule.

NGC 1976, near the Trapezium). Typical ratios are lower in
the nebular gas surrounding the Tadpole (⇠ 0.24) and lower
still in the globule and outflow (⇠ 0.20). There is a clear
trend of increasing ionization with distance from the centerof the globule. In both tracers, the ratio at the terminus of
the contiguous outflow is ⇠ 1.5⇥ greater than the ratio measured in the least ionized gas in and immediately around theglobule (see Figure 2).
Most of the lines that we detect in the outflow haveionization potentials < 13.6 eV; emission lines from more
highly ionized elements requiring more energetic photons are
significantly fainter. Notable exceptions to this trend are: (1)Neutral carbon, [C i] 8727, which is significantly brighter
than the possible C ii 6578 line, despite the fact that theionization potential of C is 11.3 eV. Both lines are seen onlyin the immediate vicinity of the globule. (2) Highly ionizedlines like [S iii] and [Ar iii], are seen in the entire outflow

and both bow shocks. Both require photon energies > 20 eV
to achieve the second ionization, although we do not detect
lines like He+ that also have ionization potentials in thisrange. (3) The detection of [N ii] but not [N i], even though
the ionization potential of N is 14.534 eV.

Tadpole metamorphasis

9

We can simultaneously compare ionization and shock
excitation in the gas using the diagnostic diagram shownin Figure 4. More highly ionized gas will have smaller[O ii]/[O iii] ratios; shock excitation will enhance the ratio S23 = ([S ii] 6717+ [S ii] 6731+ [S iii] 9068) / H . We
plot the line ratio measured in individual pixels in Figure 4
using separate colors to distinguish between di↵erent components of the system. Points in the Tadpole system occupy
a smaller portion of parameter space than sampled in theOrion Nebula Cluster (the ONC, see Mc Leod et al. 2016).
The most highly ionized gas in this study overlaps with thelower excitation proplyds in Mc Leod et al. (2016). At the
MNRAS 000, 1–18 (2019)

Figure 7. Top: Position-velocity diagram of the wide-angle outflow ([O i] 6300 Å; colorscale) and collimated jet ([Fe ii] 7155 Å; contours)
taken through the same tracing shown in Figure 2. Bottom: The peak velocity at each position of the jet/outflow determined from a
Gaussian fit to the line profile.

Figure 7. Top: Position-velocity diagram of the wide-angle outflow ([O i] 6300 Å; colorscale) and collimated jet ([Fe ii] 7155 Å; contours)
taken through the same tracing shown in Figure 2. Bottom: The peak velocity at each position of the jet/outflow determined from a
Gaussian fit to the line profile.

HH 900 outﬂowの西周縁に位置するYSOのスペクトルを抽出

Figure 8. Spectrum of the YSO, PCYC 838 (see Figure 1), that lies in the western limb of the outflow (top). Ca i absorption suggests
a G or F spectral type, although model fits suggest M? ⇠ 2.5 M (left; see Section 5). Strong Ca ii emission suggests ongoing accretion(right).

周辺からのcontaminationで、正確なスペクトル型が取れないが、近赤外線Ca II の3つの明るいemission：

MNRAS 000, 1–18 (2019)

強いaccretionが行われていることを示唆
Figure 8. Spectrum of the YSO, PCYC 838 (see Figure 1), that lies in the western limb of the outflow (top). Ca i absorption suggests
a G or F spectral type, although model fits suggest M? ⇠ 2.5 M (left; see Section 5). Strong Ca ii emission suggests ongoing accretion(right).

HH 900 outﬂow+jetを駆動しているprotostar：=> Povich+11で示唆されている星周円盤の証拠と一致
Tadpole globuleに埋もれていてMUSEでは検出不可

MNRAS 000, 1–18 (2019)globuleのBonnor-Ebert質量を見積もった ~3.7 Msun：

以前の結果よりも100倍ほど大きい

均一な密度のglobuleを仮定して、柱密度を見積もった N(H) ~ 6 x 10^23 cm^-2 （Av >~ 450 mag）-> HH 900の駆動源が近赤でも見えないほどglobuleが濃いことと矛盾しない

ionization frontでの電子密度は以前の見積もりよりも低い-> より小さな光蒸発rate、より長いglobuleのsurvival timeとなる（光蒸発がglobuleを壊すと仮定）
globuleの冷たい分子ガスの観測でこれらの見積もりが可能（Papar II参照）
Tadpole globuleが先行研究よりもオーダーでmassiveである強い証拠を示した

Accepted by Astronomy & Astrophysics

source, and investigating the origin of the emitting lines in lightof images of the jet-like structure observed in the SPHERE data.

https://arxiv.org/pdf/1909.04714

59. Investigating the nature of the extended structurearound the Herbig star RCrA using
2.1. SPHERE data
Investigating the nature of the extended structure around the Herbig
star with
RCrA
using
R CrA was observed
SPHERE(Beuzit et al. 2019) in four
integraland high-resolution
spectroscopy
integralfield ﬁeld
and high-resolution
spectroscopydi↵erent epochs, in coronagraphic mode, as described in Mesa
et al. (2019). In this paper, we use the observation of the night3
4
Elisabetta Rigliaco1 , R. Gratton1 , D. Mesa1 , V. D’orazi1 , M. Bonnefoy2 , J.2018-06-19
M. Alcala’
Antoniucci, INfrared survey ofas part, S.
of theSHINE (SpHere
5
1
4
5
6
1
1et al. 2017) guaranteed
5
Exoplanets
ChauvinF. Bacciotti , M .Dima , B. Nisini , L. Podio , M., Barbieri , R. Claudi , S. Desidera , A. Garufi , time observations,since they
were taken12
in,better
weather
conditions and reached
E. Hugot7 , M. Janson8,9 , M. Langlois10 , E.L. Rickman11 , E. Sissa1 , M. Ubeira
Gabellini
G. vanderdeeper contrast
with respect to the other sets of observations.
18
Plas2 , A. Zurlo13,14,18 , Y. Magnard15 , D. Perret16 , R. Roelfsema17 and L. Weber
The instrument was used in IRDIFS EXT mode, allowing si-

multaneous
2 observation with the integral-field spectrometer IFS
INAF/Osservatorio Astronomico di Padova, Vicolo dell’osservatorio 5, 35122 Padova;
Univ. Grenoble Alpes,(Claudi et al. 2008) and with the dual band di↵erential imager
3
CNRS, IPAG, 38000 Grenoble, France;
INAF-Osservatorio Astronomico di Capodimonte,
Salita16,2008). In this mode,and spectrograph
IRDISMoiariello(Dohlen et al.

1

IFS provides di↵raction-limited observations covering the Y andHerbig Ae/Be star R CrA周辺の広がった構造について調べた
H bands (0.95-1.65 µm), with a spectral resolution of ⇠30 in-

使用データ：

side the 1.700 ⇥ 1.700 field of view. The IRDIS sub-system, alsodi↵raction-limited, was set in its dual-band imaging mode (DBI,
Vigan et al. 2010) to simultaneously observe with the K1 and K2
Rigliaco et al.: Investigating the nature of the extended structure around the Herbig star RCrA
filters (K1=2.110 µm and K2=2.251 µm, width 0.1 µm) with a
11.000 ⇥ 11.000 field toofshedview.
observingmode
newDetails
light onon
thistheinterestingsource.
In thisandsection, we
describe the
R CrA acquired
recentyears withdata reduction are reported
inobservations
Mesa et al.of (2019).
Data in
were
acSPHERE
and SINFONIat VLT (summarizedin Table 1), andquired in pupil stabilizedmode,with a sequenceof acquisition,
FEROS at the 2.2 m telescope in La Silla. We focus here on thewhile the field of view
(FOV)
rotated.
This
allowsapplication
elongatedstructure
alreadyreportedin Mesa
et al. (2019), andof angular di↵erential
imaging(ADI,2006) spectrum
to re- of theidentified
in Figure
1, Marois
analyzinget
theal.
emissionsource,andinvestigating
theoriginoftheemittinglines in lightduce the impact of speckle noise: in general, we use an approachofimagesofthejet-like
structureobserved
inthe
SPHERE
based on a principal component analysis (PCA, Soummer etal. data.
2012) for di↵erential imaging. The IFS data allows a further
SPHEREdata cube. The IFS image, obspectral dimension 2.1.
of thehyper-data
tained using a PCARdone
along
temporaland spectral
CrA wasobservedwith SPHERE(Beuzit channels
et al. 2019) in four
(ASDI) simultaneously,with
10 inprincipal
components(Mesa in Mesa
di↵erent
epochs,coronagraphic
mode, as described
et al.
In this highlighted
paper, we use theet al. 2015) by Mesaet (2019).
al. (2019),
theobservation
presence ofofthe night
2018-06-19
as part of thedirection,
SHINE (SpHere
INfrared
an elongated structurein the north-east
as wellas thesurvey of
Exoplanets - Chauvin et al. 2017) guaranteed time observations,hint of a disk seen almost
edge-onin theimage.
In thefollowing
since they
were taken
in better
weather
conditions
and reached
we refer to this ”elongatedstructure”,
deferringinterpretation
deeper contrast
with respect
to theitsothersets of observations.
to the next sections.The instrument was used in IRDIFS EXT mode, allowing simultaneous observation with the integral-field spectrometer IFS
In the present (Claudi
paper, etwe
preferuse
al. 2008)
andto
with
the images
dual band obtaineddi↵erential imager
with a PCA done separately
on thedi↵erent
channelsand spectrograph
IRDIS(Dohlenspectral
et al. 2008).
In this mode,
IFS
providesdi↵raction-limited
observations
covering(monochromatic PCA) in order to retrieve all the informationthe Y andH
bands(0.95-1.65
µm),
with
a
spectralresolutionof ⇠30 incoming from every channel; 00this makes
it possible to highlightside the 1.7 ⇥ 1.700 field of view. The IRDIS sub-system, also
the di↵erent wavelengths
sampledintheimage.
In
addition,wedi↵raction-limited, was set in its dual-band imaging mode (DBI,
also used images thatareet obtained
subtracting
a radialViganal. 2010) to simply
simultaneously
observe with
the K1 andFig.
K2 1: Top panel: Median image obtained using monochromatic(K1=2.110byµmthe
andself-subtraction
K2=2.251 µm, width
0.1µm) witha PCA with 1 principal component for spectral channel
profile and that are filters
not00a↵ectedof
non00
11.0 ⇥ 11.0
field of
Details onimaging.
the observing
andSPHERE-IFS image, showing the continuum emission. The
uniform imaged structures
typicalof view.
di↵erential
Themodeon
data reduction are reported in Mesa et al. (2019). Data werebrightac- source at about 0.3 arcsec south-east from the center, idenmedian IFS image quired
showing
thestabilized
continuumin Yofandin pupilmode,emission
with a sequenceacquisition,
H band and the mostprominentof theHeliumat tified with B, is the M-star companion detected by Mesa et al.
while
the field ofline
viewemission(FOV) rotated.
This
allows application
which appears elongated as a consequence of the di↵erof
angulardi↵erential
imaging(ADI,
Maroisetal.
2006)
re1.083µm is shown in Figure 1. Figure 2 shows the continuum to(2019),
duce
impactspecklenoise: inand
general,use an approach
ential imaging adopted. Solid and dashed lines refer to the meemission obtained inK1theandK2ofwith
IRDIS,
the wesubtracbased on a principal component analysis (PCA, Soummer et
al. PA and aperture of the ”elongated structure” as measured indiantion of the K1-K2 filters.
2012) for di↵erential imaging. The IFS data allows a further
spectral dimension of the hyper-data cube. The IFS image,Sect.
ob- 3.2, respectively. Bottom panel: Same image as top panel,but only in channels containing Helium I at 1.083 µm line. The
tained using a PCA done along temporal and spectral channels
2.2. SINFONI data(ASDI) simultaneously, with 10 principal components (Mesa
white solid and dashed lines show the PA of the extended strucet al. 2015) by Mesa et al. (2019), highlighted the presenceof as discussed in Sect. 3. The white circle shows the size of
ture,
anCrA
elongatedin withthe north-east
direction,
as well as the
A H-band image of R
was structure
obtained
the AO-fed
integralthehint of a disk seen almost edge-on in the image. In the followingcoronagraph used.
field spectrograph SINFONI(Eisenhauer et al. 2003; Bonnet
we refer to this ”elongated structure”, deferring its interpretation
et al. 2004) operating
between
1.45–1.85 µm with a resolution
to thenext sections.

可視分光データ（FEROS）・近赤外補償光学画像（SPHERE & SINFONI）
41

R CrAについて大変興味深い系
・明るい、かなりmassive、とても若い・三重星- 中心の連星の間隔：個別成分の半径の数10倍

この半径は星周円盤のsurviveに対して重要
磁気遠心力駆動ジェットのシナリオの中で考えられている
今回、R CrA周辺の広がった構造の詳細な探査が可能となった
データにより明らかになった複雑な全体構造：(i) collimated ジェット(ii) wide cavity(iii) 中心系近傍のショック領域

In the present paper, we prefer to use images obtainedwith a PCA done separately on the di↵erent spectral channels(monochromatic PCA) in order to retrieve all the information
coming from every
channel;thismakes it possible
to highlight
Rigliaco
et al.:
Investigating
the natureof the extended structure around the Herbig star RCrA
the di↵erent wavelengths sampled in the image. In addition, we
Fig. 1: Top panel: Median image obtained using monochroalso used images that Table
are obtained
simplysubtracting
a radial-obtained
1: Logof theobservations
with SPHERE and SINFONI
profile and that are not a↵ected by the self-subtraction of non- matic PCA with 1 principal component for spectral channel
uniform imaged structures typical of di↵erential imaging. The on SPHERE-IFS image, showing the continuum emission. The
source atSpectral
about 0.3 resolution
arcsec south-east
from the center,
idenInstrument
band emissionFOV
SpaxelWavelength
coverage
medianDate
IFS image showing
the continuum
in Y and brightwith2 B, is the M-starby Mesa et al.
H bandand the most prominentline emissionof 1.7the00Helium
2018-06-19
IFS
Y-H⇥1.700 at tified
7.49mas⇠30 companion detected
0.95–1.65µm(2019), whichappears elongated as a consequence of the di↵er2
1.083µm
is shown in Figure
shows11.0
the 00continuum
2018-06-19
IRDIS1. Figure
K1,2K2⇥11.000 12.25mas—
2.11µm,2.25µm
ential imaging
adopted. Solid and dashed lines refer to the meemission
obtained inSINFONIK1 and K2 with H
IRDIS, and
00 subtrac2
2018-09-11
0.8the⇥0.80012.5mas1.45–1.85µm
dian
PA and aperture of⇠3000
the ”elongated structure”
as measured intion of the K1-K2 filters.
Sect. 3.2, respectively. Bottom panel: Same image as top panel,but only in channels containing Helium I at 1.083 µm line. The

3

(i) Collimateされたガスジェット：水素（with SINFONI）と[He I] (with SPHERE)輝線で検出

Rigliaco et al.: Investigating the nature of the extended structure around the Herbig star RCrA

wigglingパターンを示す：

Rigliaco et al.: Investigating the nature of the extended structure around the Herbig star RCrA

Rigliaco et al.: Investigating the nature of the extended structure around the Herbig star RCrA

連星系の周期と一致

Rigliaco et al.: Investigating the nature of the extended structure around the Herbig star RCrA

Fig. 6: Spectra extracted from SPHERE-IFS data, once a radial
profile, has been subtracted. Top left panel (a): spectrum (meancontrast versus wavelengths) extracted in area where”elongatedstructure” is identified, normalized for stellar peak. The locationof the Helium and Hydrogen (Pa ) line emission are labeled.
The blue line shows the linear curve utilized to normalize thespectrum, and reported in the bottom panel. Bottom left panel(b): spectrum normalized to linear fit indicated in top panel. The
grey-shaded area shows the telluric band. Top right panel (c):same as panel (a), but for a region closer to the disk identified by
Mesa et al. (2019). Bottom right panel (d): same as panel (b) for
disk.a radial
d from SPHERE-IFS data, once

Fig. 7: Peak position of Hydrogen and Helium lines fromSINFONI and SPHERE-IFS data, respectively, as a function of
distance from central objects. Dots indicate the sigma of theGaussian distribution used to obtain the peak position within theslice. The solid blue line is the fit of the wiggle if it is producedby the orbital motion of the jet around the binary system at thecenter. The blue fit in the three panels is the same, however in thepanel showing SINFONI data it is adjusted in order to accountfor the di↵erence in phase between SPHERE and SINFONI observations and for the di↵erent instrument resolution.

cted. Top left panel (a): spectrum (meangths) extracted in area where”elongated Fig. 7: Peak position of Hydrogen projected
separationlines
betweenfrom
two consecutive blobs on the sameand Helium
continuum emission does not have a wiggling pattern, even if is side of the jet will then give the helix pitch. As we have seen
normalized for stellar peak. The
location
SINFONI and SPHERE-IFS data, respectively, as a function of
appears
non-uniform.
previously, the jet transverse velocity determined in this way isdrogen (Pa ) line emission are labeled.
Another point distancecoming fromfrom
the analysisof theSPHERE-IFS
centralobjects.
Dots 760
indicateof thekm s 1 .theThe sigma
combinationof the luminosity and radial veimages in thethe di↵erent
channelsis that the emission
by obtain
the gas thee linear curve utilized to normalize
locitymaps
make it possible
determine all the parameters ofGaussiandistribution
used topeak
position
withintothe
shown by Hei line is not centered on the continuum emission. the model (see Figure 8). The PA is the mid-angle of the jet onin the bottom panel. BottomThis
leftis panel
slice.
The
solid
blue
line
is
the
fit
of
the
wiggleif
itisproduced
clear comparing the top and bottom panels of Fig. 1: the the sky plane (PA=67 , in the usual convention starting fromd to linear fit indicated in top Hei
panel.
The is notbyexactly
the orbital
motionof the jetemisaroundthetoward
binarysystematbetween
the the mean jet radial velocemission
co-locatedto the continuum
northeast).
The ratio
appearingto thesouth
direction,
almostat thebor- iss the telluric band. Top rightsion,
panel(c): shifted
center.
The
blue
fit in thethreepanelssame,
however
in sets
thethe inclination angle at which
ity theand thetransverse
velocity
der of the continuum emission, suggesting it is produced in the the helix is seen. We find i=3.3 , meaning that the jet is seenr a region closer to the disk
identified
Rigliaco
et al.: Investigatingby
the nature of the extended
structure around the
Herbig star RCrA data it is adjusted in order to accountshowing
SINFONI
external layer of panel
the ”elongatedstructure”.
Moreover, the Hei very close to the sky plane. This suggests that the disk of R Cra
om right panel (d): same as panel(b) isforspatiallyfor resolved
the di↵erence
phaseperpendicubetween SPHERE
andedge
SINFONIemissionalong the indirectionis seen almost
on. In thisobmodel, the radial velocity di↵erlar to the jet elongation,yielding
a medianjet di↵erent
semi-apertureof ence between
servations
andfor theinstrument
resolution.
opposite sides of the helix (e.g. box 1 and box 2

Fig. 3: False-color images obtained from SINFONI data cube in line emission. In green, the summed emission from the Hydrogenlines, in blue, the sum of the emission from the H2 lines, and in red, the sum of the emission from the [Fe ii] lines. Bottom-rightpanel shows the composite image obtained from the sum of the other three panels. The boxes show the regions where we extracted
the spectra for the ”jet” and ”cavity”, shown in Figure 4. Solid and dashed lines as in Figure 1: they indicate to the ”elongatedstructure” PA and aperture as identified from IFS and IRDIS continuum images.

幾何学モデルを使ってwigglingパターンを再現を試みる
速度~770 km/s、観測者に対するinclination ~3.3 のジェット（塩水表面をなぞる螺旋形）

可視禁制線（with FEROS）で見られるHVC：

fast-collimated ジェットに付随（曲がったcavityに沿う）⇠10 au.

in Figure 8) is due to a projection e↵ect, because they are moving with a di↵erent inclination with respect to the line of sight,
and then sets the cone aperture angle. The observed di↵erence
3.4. Geometrical projectedmodel of theseparation
wiggling jet between two consecutiveon the sameof ⇠18 km blobss 1 is reproduced
by a semi-aperture of the cone ofes not have a wiggling pattern, even if is side of the jet will then give the helix
Fig.
5: As
FEROS
spectrum
RCrA.
Topis panels: regions
pitch.
wehaveseen, pointing
toa verywell
collimatedof
jet. Once
this angle
We constructed a geometrical model of the wiggling jet of ⇠1.2
fixed,
theobserved
distance
betweenthe blobs
and thepanels:
jet axis regions around
R CrA, as observed
in
the
Hi
lines
in
the
SINFONI
spectrum.
around H↵in and
H islines.
Bottompreviously, the jet transverse velocity determined
this way
We modeled two observed quantities:
the luminosity and the ra- determines the radius of the base of the cone rB ⇠5.3 au.
ng from the analysis of the SPHERE-IFS[Oi]
6716/6731
and [S
760
km s 1 . The
combination of the luminosity
and radial
ve-ii] 4068/6716/6731 forbidden lines. The
The radial velocities were derived by crossMost interestingly, the model also sets the phase when thechannels is that the emission dialby velocity
the gasmaps.locity
maps
make itand
possibleto determine
all thetheparametersof at inGaussian
profilespanels refer to the mulcorrelation, and themaps ofthe intensities
radial velocities
jetcoloredcrossedbinaryorbitalplane
the theepochbottomof the SINFONI
ot centered on the continuumofemission.
the Hi lines arethe
shownin the (seetop panelsof Figure
8. In PAorderis theobservation(at a distanceofbarycenter
theHVC, in blue, themodel
Figure8). Themid-angleof thedeconvolution:
jet5.3onau from the intiple
component
green,ofthe
model
quantities, we assume that the jet is describ- central binary). Of course this is an idealization of the real jet
the top and bottom panels of toFig.
1: thesethe twothe
sky plane (PA=67 , in the usual convention
from
LVC, inred,starting
sumofcomponents.
ing a helix
on the surface of a truncated cone, which is seen trajectory
becauseitthe
is unlikely
thatthethe twojet is launchedfrom thisctly co-located to the continuum
emistowardangleeast).
ratio between
the meanjet radialwith an inclinationnorthi and position
PA Thewith respect
the sky position.
However,
this canvelocstill be useful in understanding theo the south direction, almost plane.
at theSincebor-the inclinationis verysmall, the jet
velocity setson thethejet
geometry withrespect
to the central binary. We found that
ity and thetransverse
velocity
inclination
angle
at whichmission, suggesting it is producedin thesky plane
is set by
the
ratio
of
the
separation
betweenthehethis
phase
is
0.35,
where
the
zero point is when the binary pri5: FEROS
spectrum We
of RCrA.
Topi=3.3
panels: regions
the Fig.
helix
is seen.
find, meaning that the jet is seenaroundH↵ andH lines.
Bottompanels: regionsthat
around mary
lix pitch
orbitalperiod.
In theassumptions(R CrAAa) is in opposition.
Forthe binarybetween the ”elontinuum
emission,
pointing
tocomparison,a misalignment
longated structure”. Moreover,
the andHeithe binary[Oi]6716/6731
and[S ii] sky
4068/6716/6731
forbiddenlines.
The
very
close
to
the
plane.
This
suggests
that
the
disk
of
R
Cra
the
jet
is
opticallythin,
theregionswherethespiralcrossesthemodelconstructed
in
Sissa
et
al. (2019) tells us that at the sameSpectra perpendicufrom SINFONI dataalongelongatedstructurecoloredGaussianthe
profilesin the bottom panels
refer to the mulgatedaxis
inofthecontinuum
and the gas emission.
solved alongFig.
the 4:direction
tiple
component
deconvolution:in thegreen,
thethisHVC,
inblue, the epoch,plane of the sky is
havea greater
depth
alongon.
line
of sight,
thestructure”
R CrA
Aa wasat seena phase0.459.
The di↵erenceseenalmostedge
Inmodel,
theradialvelocitydi↵erfor bothjet”jet”
andthethey”cavity”
components.
Theof the between
in red, the sum of
the twolocations
components.
yielding a mediansemi-apertureofThis
misalignment
can
noted
hence
are seenas LVC,blobs
in the luminosity
these
two 1
phasesquite2alreadysmall, and be
mayclearlybe justified
by in Fig. 1, where
ence
between
oppositeimage.
sidesWeofidenthe helix
(e.g.
box
and isbox
Hydrogen recombinationlines from
theFigure
Brackett
seriesare Thein- consideringtified two consecutive
blobs in
8 as box1
and box2.
delay of the(bottom
jet due to thetime required
reach
the He thei emission
panel)
does tonot
share the same PA(ii) 広いcavity：

sured the aperture from the IFS continuum image (Fig. 1, top
panel). The position angle (PA) of the ”elongated structure”
The SPHERE images of R CrA (IRDIS and IFS) obtained using spans from ⇠30 to ⇠70 , with a median PA of ⇠50 . The samethe monochromatic PCA with 1 principal component are shown PA and ”elongated structure” aperture is shown in the IRDISin Figures 1 and 2. In Figure 6, we show the median spectrum image, where the contour plot of the ”elongated structure” isfrom the IFS data cube. It represents the average signal within also shown. The furthest region of the ”elongated structure”
the area where we identify the ”elongated structure” normalized marked by the contours appear slightly bent toward south. We
to the stellar peak. The spectrum is dominated by continuum notice, moreover, that the dust ”cavity” region, as identified inemission: however, there is some evidence of the contribution the SINFONI image, extends outside the ”elongated structure”
due to the emission line of Heliumat 1.083 µm, and slight hints
from theIFStheandIRDISand line imRigliaco et al.: Investigating the nature ofastheidentified
extended structurearoundHerbigstar continuum
RCrA
of Paschen when the spectrum is normalized to the continuum ages. In particular, the axis of the emission in the dust ”cavity”(Fig. 6, left bottom panel). The steepness of the observed spec- region has a PA of ⇠100 .
trum shows that the ”elongated structure” continuum emission
The continuum emission of the ”elongated structure” obhas a redder color than the stellar emission. For comparison, we served in the IFS image, which represents the approaching partalso extracted the spectrum in the region where the almost edge- to the observer, covers all the IFS field of view, meaning that iton disk was pointed out by Mesa et al. (2019) (panels (c, d) in extends up to ⇠120 au from the central system. From the IRDIS
Fig. 6). We notice that while the reddening of the spectrum in the image, the radial extent of the approaching part of the observed
direction of the disk is in agreement with the spectra extracted ”elongated structure” extends up to 2.600 from the central objects
for other disks around Herbig stars (e.g., HD 100546, Sissa et al. (400 au at the R CrA distance), remaining as wide as ⇠30 up
2018 and SAO 206462, Maire et al. 2017), the spectrum along to ⇠300 au. Optically visible jets from TTSs are known to begin
the ”elongated structure” appears steeper. We must consider that with wide (10-30 degree) opening angles close to the source, andthe circumstellar environment around RCrA is a↵ected by high are rapidly collimated to within a few degrees in the innermost
extinction (e.g., Bibo et al. 1992; Sissa et al. 2019), and a gradi- 50-100 au (Ray et al. 2007; Frank et al. 2014a). Wider structures,ent of extinction within the region itself, hence the reddening of as the one observed in the continuum emission around R CrA,
the spectrum might be due to this e↵ect. However, the scattering might be consistent with shells of ambient gas swept up by theproperties of dusty grains of di↵erent size might also play a role jet bow-shock and a surrounding slower wider-angle component.
in this context.
This wide-angle wind and the swept-up outflow expand more
We analyze the aperture of the ”elongated structure”. slowly, carving out a cavity, which widens over time into the
Following on from the analysis of Mesa et al. (2019), we mea- envelope and the surrounding cloud (Frank et al. 2014a).
3.2. ”Elongated structure” size

IRDISやIFS SPHEREの連続光で見える

N-E方向に最大400 AUに広がる不均一な構造（~30 の広がり）
cavity wallは散乱光で見える

in Figure8) ispointing
dueto ato
a projectione↵ect, because they are movemission,
misalignment
between the”elondicated, together with the [Fe ii]tinuumandH2 axislines.
The
spectraareas thetocontinuum(top panel). The same happens forstructure”
seen in the inclination
continuum and the gaswith
emission.respect
ing gatedwitha di↵erent
the line of emission
sight,
This misalignment can already be clearly noted in Fig. 1, whereextracted from the two boxes shownin
Figure3.
the[Fe ii] and H2 lines shown in Figure 3, where the
He i emission
panel) does
not share the samePAand thethensets (bottom
the coneaperture
angle.
TheHydrogen,observed di↵erence
as the continuum emission (top panel). The same happens forl of the wiggling jetlines are not
emittedthe Hydrogen,lines shown in Figureby
3, wheretheof ⇠18km [Fes ii]1 andis Hreproduced
a semi-apertureof thecone atof the same PA as the continuum in Y-Hlines are not emitted at the same PA as the continuum in Y-H
andjet.
K Oncebandsthisfromthe IFSbands from the IFS
IRDIS
images.
Both collimatedHelium and,Kpointing
toandaa wiggling
very
well
angle
is and IRDIS images. Both Helium andmetrical model of the wiggling jet of ⇠1.2andHydrogenemissionsdisplay
patternwithaprojected
Morphology
Hydrogenemissionsdisplay a wiggling pattern with a projectedhalf-opening
angle of 5 – 6 . Itdistanceis not surprising between
to see a wiggle thethe observed
blobs andthe jet axis
the Hi lines 3.3.
intheMorphology
SINFONI spectrum. fixed,
3.3.
The
overallmorphology of the observed ”elongated structure” in the jet of young stars: it has been detected in both the otherin luminosity
the continuum emission
IFS raand IRDISdetermines
im- young stars where
was observed
thea jetradiusof withtheSPHERE,
base namelyof thehalf-opening
cone rB ⇠5.3angle
au. of 5 – 6 . It is not surprising to see a wiggle
ed quantities:asagesseentheandfromthe
appears non-uniform and discontinuous along the radial RY Tau (Garufi et al. 2019) and ZCMa (Antoniucci et al. 2016).
TheMoreover,overallmorphologyof the”elongatedstructure”
inthethejetphaseof young
extent.
the
SINFONIimage
a wiggling
pat- observed
Contrary tointerestingly,
these previous
studies, wherethebinarityof the also
cenradial velocities
were
derivedby shows
crossMost
the
model
sets
whenstars:
the it has been detected in both the othertern in the Hydrogen lines. We analyzed the wiggling as a func- tral object was assumed from the wiggle of the observed jet, forasofseen
infromthecontinuum
emission
from
and
IRDIS
imyoung
wherea jet was observed with SPHERE, namelytion
the distancethe central
binary by focusing
both crossed
R CrA weknow
the central
systemis a binary
star(Sissaps of the intensities
andradialvelocities
jetthethatIFS
binaryorbitalplaneat theepochstarsof theSINFONIon the emission lines and on the continuum emission. We em- et al. 2019). We checked that the rotation period of the binaryn in the top panels
ofmethodFigureIn orderobservation
distanceof di↵erence
5.3
aube-fromployedusedby8.
Antoniucci
et al. (2016):
we discontinuous
system (66 days)(atis in aagreementwith thethe
phaseagesthe same
appears
non-uniform
and
along
radial
RY theTaubarycenter(Garufi et ofal. the2019) and ZCMa (Antoniucci et al. 2016).
considered a set of contiguous slices orthogonal to the jet axis tween the two observations, SINFONI and SPHERE-IFS, which
ntities, we assume
jetpixelisdistribution
describcentral
binary).
Ofin atime.
coursethisperiodisanthe real
jet studies, where the binarity of the cenandin each thatsliceMoreover,wethe
fitted thewith a Gaussianareshiftedby ⇠twomonthsIf the observedof
the idealization
extent.
the SINFONI
image
shows
wiggling
patContrary tooftheseprevious
function in order to obtain the profile peak positions as a func- wiggling (190 mas) is linked to the period of the central binary
ace of a truncated
cone,
which
seen
trajectory
becauseit theis velocity
unlikely
thetral
jet islaunched
from this from the wiggle of the observed jet, fortionof theindistance
the star. We isappliedthis method
toanalyzed
system, we could
then wiggling
measurejet thatprojected
tern
thefrom
Hydrogenlines.
Wetheasof thea funcobject
was assumed
the SPHERE-IFS channels containing the He i line at 1.083µm, on the sky, which we found to be ⇠760 km s . This corresponds
d position anglePA
respect
theBrackett
skyseries
position.
thiscantostill
bekmusefulin understanding
totionthe SINFONI
channels
containing theto a radial However,component
respect
us ofboth⇠130
ofwiththedistancefromthelines
centralbinaryof thebyvelocity
focusing
R CrA
we know thatthe
the central system is a binary star (Sissa
at 1.555µm, 1.641µm, 1.681µm, 1.736µm, and to the IFS aver- s , if we consider that the disk is seen almost edge-on and thation is very small,jet velocity
onand
the
jet
with
respect
thecentralWeWe
foundthat that the rotation period of the binaryageemission.
The results
are shownin Fig.on
7, where
thecontinuum
jet is then seen withanemission.
inclinationof ⇠10 to
on
the
plane
of theet binary.
al. 2019).
checkedoncontinuum
thetheemission
lines
thegeometryWeemthe plots from the gas components are shown in the top pan- sky (see below). We also notice that the wiggling is not visible inratio of the els,
separation
thein thehethis
0.35,
where
the panel
zero
point
is whenbinarypri-agreement with the phase di↵erence beand the continuum
emission is method
shownbottompanel.
continuumis
emission.
Aset
shown
bottomofwe
Fig.
7,
ployedthebetween
same
used
bythephase
Antoniuccial.in the(2016):
system(66thedays)is in
We first notice that the ”elongated structure” seen in the gaseous the model obtained from the emission lines (blue solid line), usorbital period.
In (boththeHelium
assumptions
mary(RsameCrAAa)fromistheto
ingas lines,
opposition.
comparison,binarycomponent
Hydrogen)is atthata median PAof slicesing thePA measured
does
reproduceFor
considereda andsetof contiguous
orthogonal
thejetnot axis
tween
the two theobservations,
SINFONI and SPHERE-IFS, which⇠65 , higher than the median PA (⇠50 ) found from the con- the shape of the observation, pointing to the conclusion that thethe regions where
spiralthe themodel
constructed in
Sissa
et al. (2019)aretells
us thatthe sameand inthe
eachslicecrosses
we fitted
pixel distribution
witha Gaussian
shiftedbyat⇠twomonths in time. If the observed period of thea greater depth
along intheorderline toof obtainsight, theepoch,
thepeak
R CrA
Aa wasa phaseof 0.459. (190
The di↵erence7function
profilepositionsas ata funcwigglingmas) is linked to the period of the central binary
blobs in the luminosity
We from
iden- thebetween
these
two phases
is quite tosmall,system,
and mayjustifiedtion of theimage.
distancestar. We
appliedthis method
webecould
thenbymeasure the velocity of the jet projected
Fig. 4: Spectra from SINFONI data along the elongated structure
for both ”jet” and the ”cavity” components. The locations of the
8 the Brackett series are inHydrogen recombination lines from
dicated, together with the [Fe ii] and H2 lines. The spectra are
extracted from the two boxes shown in Figure 3.

62

fast-collimated ジェットはcavityの南側を向いているように見える=> 広いcavityの中心を示していない、おそらく歳差運動に起因
1[Fe II]輝線：

1

cavity wallに沿って検出

Fig. 8: Top panels: Intensity and velocity map of HI lines obtained from SINFONI data. The intensity map is obtained by measuring
the sum of the intensity of the HI lines in each pixel, and the velocity map is obtained from the cross-correlation function of theimage using a correlation mask. Bottom panels: intensity and velocity maps of model. Box1 and box2 identify the two consecutive
blobs that are used to build the geometrical model of the wiggling, as discussed in the text.
a distance of 5.3 au from the star at a constant speed of 700
km s 1 , 12 days, that corresponds to a phase di↵erence of 0.18.
Of course, the jet trajectory is likely shorter than one passing
through this ideal point. Even if these values contain some uncertainties (e.g. in the exact jet trajectory and velocity and in the=> より遅いwindに起因（disk wind）。可視禁制線で見られるLVCも生む

layer of the ”elongated structure”. They have low velocities, andare narrow and not resolved in the SINFONI spectrum. The ratio between the intensity of the lines at 1.64 and 1.53 µm is adiagnostic of density (Nisini et al. 2005). The observed ratio of
about four corresponds to a density of about 104 cm 3 . This isTable 3: Radial velocities and FWHM for spectral lines detected possible to see the far side of the disk. Also, the separation bein SINFONI spectra. vc and FWHM were derived by cross- tween the central binary components projected along the jet axis
correlationand fitting of the following lines. Hydrogen: Brackett is very small (about 0.3-0.4 mas) and can thus be neglected here.
(iii)
中心星に近いショック領域：
series lines from H(11-4) up to H(21-4); [Feii]: 1.53347, Since the scope of spectro-astrometry is to explore regions very
1.59948, 1.66377, 1.67688, 1.711132; H2 : 1.70150, 1.71427, close to the center of the system, we used the images obtained
より高密度域で、H2（with SINFONI）や[Fe II]@7155Å(with FEROS)を生成
1.72902,
1.73202.
by subtraction
a radial the
profile.
imageswerearoundcorrected
forstar RCrA
Rigliaco et al.:ofInvestigating
nature ofThethe extended
structure
the Herbig
the telluric lines and then cross-correlated with digital masks for
Table 3: Radial velocities and FWHM for spectral lines detected possible to see the far side of the disk. Also, the separation beComponentvc
FWHM
HI and[FeFWHMii] (resultsfor H2bylines
less clear). The resultin SINFONI spectra.
vc andwere derived
cross-were
tween the central binary components projected along the jet axis
(km s 1 )(km s 1 )ing data
cube is lines.
then Hydrogen:made ofBrackett
cross correlation- thatcorrelation and fittingof the following
is very smallfunctions(about 0.3-0.4mas) and can thus be neglected here.
Star
series lines fromup to H(21-4);
1.53347,is, H(11-4)
the z-coordinate
now[Feii]:
represents
radialvelocities.
then roSince
the scope ofWe
spectro-astrometry
is to explore regions very
1.59948,1.66377,
1.67688,
1.711132;H:
1.70150,
1.71427,H-14.8±4.0 435±142close tothey-axis,
center ofandthe system,
we used the images obtained
tated
these
images
so
that
the
jet
is
along
the
col1.72902, 1.73202.
by subtraction of a radial profile. The images were corrected for”Jet”
lapsed the images along the jet. This isweobtainedbidithehow
telluric
lines
and then cross-correlatedwith digital masks forH-39.9±2.4393± 7
mensional images,
where the axes are HI
radialvelocity
andforo↵setComponentvc
FWHM
and [Feii] (results
H2 lines were less clear). The resultH (box 1)-29.7±3.0
383± 9
1
1
)
(km
s )
is then madeof cross correlation functions - thatalong the (kmjets withrespect
to the peaking
of datathecubecontinuum
emisH (box 2)-45.3±2.7
410± 9Star
is, thez-coordinate
now
represents
radial velocities. We then rosion.
We
thenfittedGaussians
in
o↵set
as
a
functionofradialH-14.8±4.0 435±14H2+0.7±4.9174±12tated these images so that the jet is along the y-axis, and col”Jet”
velocity
andcomparedtheposition
of
the
peak
with
the
value
lapsed the images along the jet. This is how we obtained bidi”Dust Cavity”
H-39.9±2.47weobtainedfor the393±
continuum(that, weremindimages,
readers,
mensional
wherereprethe axes are radial velocity and o↵set[Feii]-0.2±4.5
208±12H(box
1)-29.7±3.0383±9
これら輝線の速度・FWHM：
along thejetHVCとLVCの間にある
withrespect
to the peak of the continuum emisposition of
the
there
is no
relevant
Hsents(box 2) the -45.3±2.7
410±
9 warm disk). SinceH-6.6±8.1
423±26sion. We then fitted Gaussians in o↵set as a function of radial
H2variation +0.7±4.9
174±12 of this peak withof the position
velocity,
wesimplyvelocity and compared the position of the peak with the value”Dust Cavity”
considered-0.2±4.5
the average
fortheHI
lines is(that, we remind readers, repreweobtained
obtained forcontinuum[Feii]
208±12values. The peak
the positionof theHo↵set by about-6.6±8.1four
423±26
mas in the oppositesents
direction
to thejet:warm
thisdisk). Since there is no relevant
variationof the positionof this peak with velocity, we simply
The relative intensity of the di↵erent H2 lines agree, within indicates that the bulk of the H emissioniscausedbymaterial
considered the average values. The peak obtained for HI lines is10%, with what was expected from collisional excitation at a very close to the central binary, likely tracing
accretion.
o↵set bythe
aboutfour mas inThis
the opposite direction to the jet: thistemperature of about 15000 K, and it is very di↵erent from
Thewhatrelative intensityofthedi↵erentH
lines
agree,
withinindicates
thatotherthe bulkof thethe
H emission is caused by material
agrees with the large 2value of the FWHM.
On the
hand,
10%,
with
what
was
expectedfromcollisional
excitationata
was expected from fluorescence models (Black & van Dishoeck peak for [Fe ii] is o↵set by about two masvery inclose
todirection
the central binary,
likely tracing the accretion. This
the
of
the
temperature of about 15000 K, and it is very di↵erent from what agrees with the large value of the FWHM. On the other hand, the1987).
Namely, mainly
low-excitation lines are observed,
and
R
CrA：
未だよく理解されていないHerbig星周囲のジェットの構造の研究ができる、非常に面白い天体
jet,fluorescenceindicating
that,(Blackin thiscase,the bulk
offorthecomes
was expected frommodels& van
Dishoeckpeak[Feemissionii] is o↵set by
about two mas in the direction of thethe high-excitation lines, which are also expected to 1987).
be strong
Namely, mainly
are observed,
either low-excitationfrom the jetlines
or fromregionsand
closejet,toindicating
the disk,
atinaboutsixthe bulk of the emission comesthat,
this case,the high-excitationlines, which are also expected to be strong either from the jet or from regions close to the disk, at about six
due to fluorescence, are absent. The high-temperature gas
can be mas
(⇠
1
au)
from
the
star
projected
along
the
jet
axis.
duelocatedto fluorescence, are absent. The high-temperature gas can be mas (⇠ 1 au) from the star projected along the jet axis.
全体シナリオ：
heatedby shocks (Shull & Beckwith磁気遠心駆動ジェットの一般的な予測とよく一致
1982) that may beheated by shocks (Shull & Beckwith 1982) that may be locatedclose to the base of the jet or in the regions where thiscloseinteracts
to the base of the jet or in the regions where this interacts
4. Proposed
scenarioand discussion
with the disk. Radial velocities and FWHM of the Hydrogenwith the anddisk. Radial
velocities and FWHM
of the Hydrogenand 4. Proposed scenario and discussion
H2 linesin the ”jet” area are in agreement with the values foundH2 lines in the=>”jet”しかし、三重連星ということでシナリオは複雑に。
area are in agreement with the values
found
this section,
we discussa scenario where all the features,
In thiswe spectrum,
discuss suggestinga scenarioInwhere
all thefeatures,for the [Fe ii] at 7155
Å linesection,in the FEROS
structures, and properties seen and analyzed in the ”elongated
for the [Fe ii] at 7155 Å line in the FEROS spectrum, suggesting
5
3
that
this
line
(that
requiresdensities
as
high
as
⇠10
cm
,
Nisinistructures,andproperties
seen
andanalyzedinthe”elongatedstructure” are taken into account. The proposed scenario is supthat this line (that requires densities as high as ⇠105 cmet 3al., Nisini2005) might
be also producedin the intosame account.
post-shock The
re- proposed
structure”
are taken
is supported by atscenario
least a similarcase, the T Tauri star FS Tau B obgion
near
the
star.
et al. 2005) might be also produced in the same post-shock re- ported by at least a similar case, the Tserved
bystar
Eislö↵el& Mundt(1998), who imaged the ”elongated
Tauri
FS
Tau
B
obWe notice that the H2 lines, which should dominate the K1- structure” as the wide outer edgesof windblown cavities and thegion near the star.
非常に若い星からのジェットの理解において、この特殊な天体との関連を考えるとさらなる観測が必要
servedby
Eislö↵el&Mundt(1998),
who
imagedthe”elongatedband in the IRDIS image, are not detected. To stress this point, narrower jet flowing inside the cavity in H↵.
We notice that the H2 lines, which should dominate
theK1we performed thesubtractionasof thethe wide
K1-K2outer
IRDISedges
image,ofas windblown
structure”
cavities
andwetheThe schematic
pictureconsider is obtained from the comshownpoint,
in Fig. 2 narrower(bottom panel).
On the other
hand,thefainter
H2 inplementaryband in the IRDIS image, are not detected. To stress thisdetailed analysis of the SPHERE (IRDIS and IFS)
jet
flowing
insidecavityH↵.
すなわち、
are detectedin the H-band SINFONI spectrum. This non- images and spectra, of the SINFONI data, and of the optical
we performed
the subtraction of the K1-K2 IRDIS lines
image,
asschematic
picturedue
wetoconsider
obtained from the comdetection of H2 in the The
K1-K2
image is essentiallythe fact is
FEROS spectrum. The system appears to be composed of at least
shown in Fig. 2 (bottom panel). On the other hand, fainterH
2 hasplementarythat SPHERE
been designeddetailed
for detecting
continuum
analysisof emisthe SPHERE(IRDIS
andIFS) seen in scattered light, and atwoelements:
a dustycomponent
・可視・近赤外線での高分解能分光
lines are detectedin the H-band SINFONI spectrum. sion,
Thisitnonis not optimized
detecting(extended)
lineSINFONI
emission. gaseous
imagesforand
spectra,of thedata, andof thedetected
opticalcomponent,in emission atomic lines of forbidspectralof SINFONI is two orders of magnitude den species ([O i], [He i] and [Fe ii]) and Hydrogen lines. Whatdetection of H2 in the K1-K2 image is essentially due The
to thefactresolution
FEROS
spectrum.
The
systemappearstobecomposed
of
at
least
higher: this makes it possible
to detect emission lines with a sur- we have called ”elongated structure” until now, which is seen
・回折限界integral-ﬁeld分光（e.g.,
SPHERE、MUSE、ERISなど）
that SPHERE
has been designed for detecting continuum
emis- twoorders
elements:
a dustycomponent
seenininscatteredscattereda IRDIS images, as well as inface luminosity twoof magnitude
fainter.
We verified thatlight light,
in the and
IFS andsion, it is not optimized for detecting (extended) line theemission.
non-detectiongaseous
if the brightest
H2 emission
line inin
theemission
K1- the atomic
component,
detected
ofisforbidSINFONIlines
image,
dominated by continuum emission andband (at 2.12µm, (S(1)(1-0))) is compatible with the detection of is most likely a cavity carved out into the circumstellar enviThe spectral
resolution of SINFONI is two orders of magnitudeの追観測が、異なるlineが放射される領域に対して有効
den species([O i], [He i] and [Fe ii]) and Hydrogen lines. What
the brightest
line in the H-band (at 1.74µm, (S(7)(1- ronment; the dust on the cavity walls is illuminated by the cenhigher: this makes it possible to detect emission lines witha sur-H2 emission
we have called ”elongated structure” until
now, which is seen0))).
tral binary and scatters light toward us. The jet flowing inside
face luminosity
two orders of magnitude fainter.
We verified that in scattered light in the IFS and IRDIS・fast-collimatedジェットの解釈に使われる力学モデル
images,as wellasHVC
in of the optical forbidden lines
the cavity
is detectedin thethe non-detection if the brightest H2 emission line in the K1- the SINFONI image, is dominated by andin the broademission
Hydrogen andlines. The jet is very collimated andcontinuum
3.6. Spectro-astrometry: information on the verycentral
band (at 2.12µm, (S(1)(1-0))) is compatible with the detectionof is most likely a cavity carved out intoshows
wiggling pattern in
the Hydrogen and [H i] lines, which
the acircumstellar
enviregionsin agreement with the orbital period of the central binary. The
the brightest H2 emission line in the H-band (at 1.74µm, (S(7)(1- ronment; the dust on the cavity walls isis illuminatedthe cenSome information about the very central region of the system LVC of the opticalby
forbiddenlines suggests the presence of gas
0))).
ジェットの発生領域：
ALMAを使ってのジェットの高空間分解能・高分解分光観測
and scatterslight&toward
Themorejet flowing
insidecan be obtainedtral
usingbinary
spectro-astrometry(Whelan
Garcia us.
movingslowly, most
likely a disk wind. SINFONI data al2008) on the SINFONI
data.isWedetectedshould remindlows
us to spatiallyresolvethe [Fe ii] emission, which appears
the cavity
in thereaders
HVCthatof theopticalforbidden
lines
例えば、ジェットの回転速度を決定に使われる
be located at the edge of the cavity, consistent with a layered
the bulk of the emission from R Cra in the near-IR is due to to
and
in
the
broad
Hydrogenlines.
The
jet
is
very
collimatedand3.6. Spectro-astrometry: information on the verycentral
the warm disk (Sissa et al. 2019). Interferometric observations disk wind as well. This structure is captured in the schematicshows
a wiggling
patternin 2009)
the Hydrogen
andof [Hi] CrAlines,
which that is shown in Figure 9. The
with the instrument
AMBER
at VLTI (Kraus
et al.
indi- picture
the R
environment
regions

58. CHIMPS:
Physicalproperties
ofclumps
molecular
across the inner Galaxy
CHIMPS: Physicalpropertiesof molecularacross theclumps
inner Galaxy
Andrew J. Rigby1,2 , Toby J. T. Moore2 , David J. Eden2 , James S. Urquhart3 , Sarah E. Ragan1 , Nicolas
Peretto1 , Rene Plume4 , Mark A. Thompson5 , Malcolm J. Currie6 and Geumsook Park7
1School of Physics & Astronomy, Cardiﬀ University, Queens Building, The Parade, Cardiﬀ, CF24 3AA, UK; 2
Astrophysics Research Institute, Liverpool John Moores University, IC2, Liverpool Science Park, 146 Brownlow Hill,
3
Liverpool;
Centrefor Astrophysics
and Planetary Science, The University of Kent, Canterbury,CT2 7NH, UK;
13CO
(3-2)
& C18O(3-2)のCHIMPSデータとCOHRS
13COKent(3-2)データを組み合わせるためにLTE解析
4
Department of Physics and Astronomy, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4,
Canada; 5 Centre for Astrophysics
Research, Science & Technology Research Institute, University of Hertfordshire,を使用して、13CO(3-2)の励起温度・光学的厚み・柱密度を、voxel-by-voxel基準で決定した。
College Lane, Hatfield, Herts AL10 9AB, UK; 6 RAL Space, Rutherford Appleton Laboratory, Harwell Oxford, Didcot,
Oxfordshire OX11 0QX, UK; 7 Korea Astronomy and Space Science Institute, 776 Daedeokdae-ro, Yuseong-gu, Daejeon
34055, Republic of Korea

FELL
WALKERアルゴリズムを使って13CO (3-2)データでのソースを抽出
E-mail contact: rigbya at cardiﬀ.ac.uk

The latest
generation of high-angular-resolution unbiased Galactic plane surveys in molecular-gas tracers are enabling=>
4999候補天体から3664分子クランプを同定
the interiors of molecular clouds to be studied across a range of environments. The CO Heterodyne Inner Milky Way
Plane Survey (CHIMPS) simultaneously mapped a sector of the inner Galactic plane, within 27.8◦ ≤ ℓ ≤ 46.2◦ and◦高密度クランプや分子雲を持つアソシエーションを介して、クランプまでの力学的距離を決定|b| ≤ 0.5
, in 13 CO (3–2) and C18 O (3–2) at an angular resolution of 15 arcsec. The combination of the CHIMPS data
12
with CO (3–2) data from the CO High Resolution Survey (COHRS) has enabled us to perform a voxel-by-voxel
local-thermodynamic-equilibrium (LTE) analysis, determining the excitation temperature, optical depth, and column
density of 13 CO at each ℓ, b, v position. Distances to discrete sources identified by FellWalker in the 13 CO (3–2)
emission
maps were determined, allowing the calculation of numerous physical properties of the sources, and we present
分子クランプ集団の3553の物理性質を調べた
the first source catalogues in this paper. We find that, in terms of size and density, the CHIMPS sources represent
an intermediate population between large-scale molecular clouds identified by CO and dense clumps seen in thermal
CHIMPSとCOHRSデータ間での距離決定や一致はある
dust continuum emission, and therefore represent the bulk transition from the diﬀuse to the dense phase of moleculargas. We do not find any significant systematic variations in the masses, column densities, virial parameters, mean
excitation temperature, or the turbulent pressure over the range of Galactocentric distance probed, but we do find ashallow increase in the mean volume density with increasing Galactocentric distance. We find that inter-arm clumps(1) CHIMPSクランプの質量・半径・密度・励起温度・力学的
life-time：
have significantly narrower linewidths, and lower virial parameters and excitation temperatures
than clumps locatedin spiral arms. When considering the most reliable distance-limited subsamples, the largest variations occur on the
分子雲（GalacticRing(1-0)でトレース）と高密度クランプ（ATLASGALのダスト連続光clump-to-clump scale, echoing
similarSurveyの13CO
recent studies that suggestthat the star-forming process is largely insensitive
to the Galactic-scale environment, at least within the inner disc.

でトレース）の中間に位置する
Accepted by Astronomy & Astrophysics

https://arxiv.org/pdf/1909.04714得られた平均体積密度や質量-半径面の観点から、

CHIMPSクランプがそれらの間の分子雲サブ構造の中間フェーズを表すと解釈
Investigating the nature of the extended structure around the Herbig star RCrA using
integral field and high-resolution spectroscopy

Elisabetta Rigliaco1 , R. Gratton1 , D. Mesa1 , V. D’orazi1 , M. Bonnefoy2 , J. M. Alcala’3 , S. Antoniucci4 ,45(2) 平均クランプ励起温度は~5̶25K）1, S. Desidera1 , A. Garufi5 ,F. Bacciotti5 , M .Dima1 , B. Nisini, L. PodioK（平均は11.5, M., Barbieri6 , R. Claudi
7
8,9
10
11
1
E. Hugot , M. Janson , M. Langlois , E.L. Rickman , E. Sissa , M. Ubeira Gabellini12 , G. van der
Plas2 , A. Zurlo13,14,18 , Y. Magnard15 , D. Perret16 , R. Roelfsema17 and L. Weber18
1
INAF/Osservatorio Astronomico
di Padova, Vicolo dell’osservatorio 5, 35122 Padova; 2 Univ. Grenoble Alpes,(3) 平均乱流圧：
熱的圧力の約60倍
3

CNRS, IPAG, 38000 Grenoble, France;

INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello 16,

41

TOPCAT, an interactive
graphical
viewerand editor app
an astronomical
imaginganddata-visualizationa mean value
11.5 K. vol- tion has also made use of2003),
12
tween approximatelyume,
5–25with
K throughout
theofsurveyed
data software Clerk
2005), Telescopeand SAOImageDS9(Joye& Mandelhas historicallybeen
operated by tiii)value
The ofmedianturbulent pressure is a factor offor⇠tabular
60 larger
than (TaylorMaxwell2003), an astronomical imaging
anddata-visualization
application.
The
James Cume, with a mean
11.5 K.
Centreonbehalfofthe
ScienceandTechnology
Facilities
0.41
thethermalpressure.
(4)TheCHIMPSクランプのfullサンプルのサイズ-線幅の関係はσhas historically
been operated
byCouncil
the Jointν R Telescope
σiii)
median turbulent pressure is a factor of ⇠ 60 larger than Clerk Maxwell
Kingdom,
the National
Research
ofAstronomy
Canada and theiv)
Thesize–linewidth
relation
of
the
full
sampleof
CHIMPS
Centreonbehalfofthe
ScienceandTechnology
Facilities
CounciloftheUnitedisationfor
Scientific
Research.
This
researchused
the facili
the thermal pressure.
0.41
Kingdom,the
National
Research
Councilof
Canadaandthe
Netherlands
Organclumpsis/R,
similartothecanonical
relationshipv
Astronomy
Data
Centreoperatedbythe
National
Research
これは銀河系分子雲の標準的な関係に似ている。
iv) The size–linewidth
relation of the full sample of CHIMPS isation for Scientific Research. This research used the facilities of the CanadianMilky Way
molecular clouds, but we find a steeper slope with the support of the Canadian Space Agency, and has ma
0.41
clumpsis v / R for, similar
to0.63σとなりより急になる
Astronomy Data Centre operated
by theData
National
Research
Councilsoftwareof Canada
0.63the canonical relationship
が、距離限界のサンプルを考える時はσν aRdistance-limited
Astrophysical
System.
The Starlink(Currieof/R
when
considering
samplev
Space
Agency,
and
has
made
use
of
the
NASA
for Milky Way molecular clouds, but we find a steeper slope with the support of the Canadian
rently supported by the East Asian Observatory.
thatought to abedistance-limited
more robust against
distance-related
0.63
Astrophysicalbiases.
Data System. The Starlink software (Currie et al. 2014) is curof/
R
when
considering
samplev
サイズー密度の関係はより緩やかになる
rently typicallysupported by
the East Asian Observatory.
size–density
relationship is shallower
obthat ought to be moreTherobustagainst distance-relatedbiases. than
0.84
0.68
served, withand v ob/ n̄(H2 )for the full
フルサンプル：v / n̄(Hthan
2 ) typically
The size–density
relationshipis shallowerand) distance-limited
0.84
0.68 respectively.
Referencesserved, 距離限界サンプル：
with v / n̄(Hand v / n̄(Hsamples,for the full
2
2)
v) We
do notrespectively.
see any evidence for a significant systematicand distance-limited
samples,
References
Allen, C. W. 1973, Astrophysical Quantities (University o
trend
with
Galactocentric
distance
of
the
clump
masses,Press, 3rd ed.)v) We do not see any evidence for a significant systematic
Allen, C. W. 1973,
AstrophysicalQuantities (Universityof London,
Athloneradii,
mean
columndensities,
excitation
temperatures,
turAstropy
Collaboration,
Price-Whelan,
A. M., Sipőcz,
B. M.,(5)trend
クランプの質量・半径・平均柱密度・励起温度・乱流圧・ビリアルパラメータと銀河中心からの距離にwith Galactocentric distance of the clump masses,
Press,
3rded.)
123
bulentpressures,orvirialparameters.
There
is
a
shallow
radii, mean column densities, excitation temperatures, tur- Astropy Collaboration, Price-Whelan,
A. M., Sipőcz,
B. M., et
AJ, 156,は、系統的傾向は見えない
Robitaille,
T. al.
P., 2018,
Tollerud,
E. J., et a
the averageTherevolumeas a func- Astropy Collaboration,
123
bulent pressures, or trend
virialfor
parameters.
is adensity
shallowto increase
A33
of Galactocentric
distance,a factorof ⇠ Collaboration,
2 increase Robitaille,
Astropy
Tollerud, E.
al. 2013, C.,
A&A,
trend for the averagetion
volumedensity to increase
as witha funcBarnes, A.T.T.,P.,Longmore,
S. J.,
N.,etBattersby,
et al.558,
2017, Movertheprobed
range
(4
<
R
<
8
kpc).
A33
GC
P. J., Muller, E., Indermuehle, B., et al. 2015, ApJ, 8tion of
Galactocentric distance, with a factor of ⇠ 2 increase Barnes, A. T., Longmore,Barnes,
平均体積密度では、銀河中心からの距離に対して増えている傾向がわずかに見える
S. N., Battersby,
C., et al.
2263
vi)Comparisonofthephysicalproperties
ofclumpslocatedBergin,E. A. & Tafalla,
M.2017,
2007,MNRAS,
ARA&A,469,
45, 339over the probed range (4 < RGC < 8 kpc).
Barnes,that
P.4J.,<
Muller,B., etAstronomy
al. 2015, ApJ,
6
RGCE.,<Indermuehle,
8 kpcの範囲で約2倍にBerry,
D. S. 2015,
and812,Computing,10, 22spiralarms andregions reveals
clumpsvi) Comparison of the within
physicalproperties
ofinter-arm
clumps locatedBergin, E. A. & Tafalla, M.
2007,
ARA&A,
45,
339
Blitz,
L.
&
Stark,
A.
A.
1986,
ApJ,
300,
L89
residing
withininter-arm
have, onaverage,lower
Berry,
D. S. 2015,
Astronomy
andwithin spiral arms andinter-arm
regionsrevealsregionsthat clumps
Boggs,
P. Computing,T. & Rogers,10,J. 22
E. 1990, in Statistical analysis ofvelocity
dispersions,virialparameters,
andexcitation
temBlitz,
L.
&
Stark,
A.
A.
1986,
ApJ,
300,
L89
models and applications: proceedings of the AMS-IMS(6)residing
spiral armとinterarmのクランプで物理量を比較
within inter-arm
regions have, on average, lower
Boggs,
P. T. & Rogers,
J. E.research
1990, inconference
Statistical held
analysismeasurement
peratures.
Thisdi↵erenceinlinewidths
isin
agreement
with
Juneof
10-16,
1989, Vol.error
112, 186
velocity dispersions, virial parameters, and excitation temmodels
andapplications:proceedingsoftheAMS-IMS-SIAM
joint
summerBonnell,I.
A.,
Smith,
R.
J.,
Clark,
P.
C.,
&
Bate,
M. R. 2the smoothed
particleof Duarteinter-armの中のクランプ：
平均的に速度分散・ビリアルパラメータ・励起温度が小さい（低い）。
peratures.
This di↵erencein linewidths
is inhydrodynamics
agreement withsimulation
research conference held 2339
June 10-16, 1989, Vol. 112, 186& Dobbs (2016),
andof
theDuartedi↵erenceBonnell,in virial
paramI. A.,
Smith, R.Braiding,J., Clark,C.,
P. Burton,C., & Bate,
M.Blackwell,
R. 2011, MNRAS,
410, PASthe smoothed particleCabralhydrodynamics
simulation
M. G.,
R., et al. 2015,
eters
isconcordantwiththefindingsofPettittetal.
(2018).
2339
16のSPHシミュレーションによく合う
Brand, J. & Blitz, L. 1993, A&A, 275, 67
Cabral &線幅の違いはDuarte-Cabral
Dobbs (2016), and the di↵erence&in Dobbs
virial paramvii) The median value of the radius distribution
forC.,clumps
Braiding,
Burton, M. G.,
Blackwell,R., etR.al.E.,
2015,
PASA,
J. V., Hills,
Smith,
H., et32,
al.e020
2009, MNRAS, 3
eters is concordant with the findings of Pettitt et al. (2018). Brand, J. & Blitz, L. 1993,Buckle,
A&A,
275,
67
ビリアルパラメータの違いはPettitt+18で見つかったものと一致
withinthe
Sagittarius
spiralarm
issignificantly
higherthan
Caputo, F., Marconi, M., Musella, I., & Pont, F. 2001, A&Avii) The median value of the radius distribution for clumps Buckle, J. V., Hills, R. E.,Churchwell,Smith, H., etE.,al.Babler,
2009, MNRAS,
399, M.
1026
B. L., Meade,R., et al. 2009, PAof thespiralthanarm, though
we can not Musella,
within the Sagittariusthat
spiralarmScutum-Centaurus
is significantly higher
Caputo, F., Marconi, M., Colombo,
I.,D.,& Hughes,Pont, F. 2001,
A&A,
372,
A., Schinnerer, E.,544
et al. 2014, ApJ, 7
exclude thepossibility
that thispartiallya result of E.,
detectBabler, B.
L., Meade,R., et al. 2009,
121, 213 A., et al. 2
Colombo,D.,M.
Rosolowsky,
E., PASP,
Duarte-Cabral,that of the Scutum-Centaurus
spiralarm, thoughweiscannot Churchwell,ingthatmore
structurenearer Sagittarius(7)exclude
Sagittarius
spiralarm内クランプの半径分布の平均値はScutum-Centaurus
Colombo, D., arm.
Hughes, A., Schinnerer,E., et al. 2014, ApJ, 784, 34290 armのよりもかなり高い
the possibility
thisextended
is partiallya resultinofthe
detectColombo,
D.,
Rosolowsky,
E.,
Duarte-Cabral,A., etSeries
al. 2019,
MNRAS, 483,viii) Even considering the modest variations in some properties Combes, F. 2000, Advancedin Astrophysics
and Cos
ing more
extendedstructureinthenearerSagittarius
arm.
より近いSagアームのより広がった構造を検出している結果の可能性は排除できていないが4290
Currie,M.
J.,Berry,
D.
S.,
Jenness,
T.,
et
al.
2014,
in Astro
thatvariations
vary within Galactocentric
or betweenviii) Even considering thefoundmodestsome propertiesdistance,
Combes, F. 2000, Advanced theSeriesin
Astrophysics
andCosmology,
10,
143
Pacific Conference Series, Vol. 485, Astronomical Dat
and inter-arm
regions,
the variation
inM.
allJ.,properCurrie,
Berry, D. S., Jenness,T., etXXIII,
al. 2014,
in Astronomical
Society 391
offound that vary withspiral-arm
Galactocentric
distance,or between
and Systems
ed. N.
Manset & P. Forshay,
ties
from
clump-to-clump
isfar
greaterthananysystematic
the Pacific Conference Series, Vol. 485, Astronomical Data Analysis Softwarespiral-arm and inter-arm regions, the variation in all properand
Systems
XXIII,
Manset & P. Forshay, 391
environmental
dependence.
Thissuggeststhattheimpactof ed.6 N.https://astropy.org/
ties from clump-to-clump is far greater than any systematic

4
LNCMI, UPR 3228,
https://arxiv.org/pdf/1909.12666
5

CNRS-UGA-UPS-INSA, 31400 Toulouse, France
INAF (Istituto
Nazionaledi Astrofisica)
Osservatorio
Astronomico
di Palermo,
Palermo,Italydesign
57. Laser
experiment
for thestudy of -accretion
dynamics
of Young
Stellar
Objects:
6
LERMA,
Observatoire
dedynamics
Paris, PSL
Research
CNRS,
Laser experiment
for the studyof accretionof Young
StellarUniversity,
Objects: designandscalingand scaling Sorbonne University, UPMC Univ. Paris 06, F-75005, Paris, France
7 1,2 , B. Khiar3 , J. Béard4 , R. Bonito5 , S. Orlando5 , M.V. Starodubtsev2 , A. Ciardi6 and J.
G. Revet
1,2,7 ELI-NP, ”Horia Hulubei” National Institute for Physics and Nuclear Engineering,Fuchs
30 Reactorului Street, RO-077125, Bucharest-Magurele, Romania
1
LULI - CNRS, École Polytechnique, CEA: Université Paris-Saclay; UPMC Univ Paris 06: Sorbonne Universités- F-91128 Palaiseau cedex, France; 2 Institute of Applied Physics, 46 Ulyanov Street, 603950 Nizhny Novgorod,3
A newexperimental
set-up designed
to investigate
the&accretion
in ofnewly born stars is
Russia;Flash
Center for Computational
Science, Departmentof Astronomy
Astrophysics,dynamics
The University
4
5
Chicago, IL, UnitedStates; advantage
LNCMI, UPR 3228,
31400 Toulouse,
France;produced
INAF (Istitutopresented.
It takesof aCNRS-UGA-UPS-INSA,
magnetically collimatedstreamby coupling a laser6
Nazionale di Astrofisica) - Osservatorio Astronomico di Palermo,
Palermo, Italy; LERMA, Observatoire de Paris,
5
generated
expanding plasma to a 2 ⇥ 10 G (20 T ) externally applied magnetic field. The stream
PSL Research University, CNRS, Sorbonne University, UPMC Univ. Paris 06, F-75005, Paris, France; 7 ELI-NP,
is“Horia
usedas theaccretioncolumnandis launchedonto
an obstacle
targetthat mimics the stellar
Hulubei”
National
Institute forPhysics andNuclearEngineering, 30
Reactorului
Street, RO-077125,
BucharestMagurele,
Romania
surface. This setup has been used to investigate in details the accretion dynamics, as reported in
E-mail[1].
contact:
guilhem.revet
at u-bordeaux.fr of the stream are detailed and a link between the experimental
Ref.
Here,
the characteristics
A new experimental
set-upanddesigned
to investigate
the accretion
dynamics
in newlystars is presented.
It takes
plasmaexpansion
a 1D
adiabatic
expansion
model
isbornpresented.
Dimensionless
numbers areadvantage of a magnetically collimated stream produced by coupling a laser-generated expanding plasma to a 2×105 G
also
in magnetic
order totheexperimental
and itsontocloseness(20 T )calculated
externally appliedfield.characterize
The stream is usedas theaccretion column flow
and is launched
an obstacle to the ideal MHD
target thatWe
mimicsthe stellar
surface. between
This setup has
used to investigate
in detailsdynamics
the accretion anddynamics,
regime.
build
a bridge
ourbeenexperimental
plasmathe asone taking place in
the Classical T Tauri Stars (CTTSs), and we find that our set-up is representative of a high plasma
40
CTTS accretion case.

INTRODUCTION

ccretion of matter occurs in a variety of astronomiobjects. Examples include black holes in the center
Active Galactic Nuclei (AGNs), pulsars, binary stars
h as white dwarfs accreting material from their comion star, and isolated low mass, pre-main-sequences.
he accretion in Classical T Tauri Stars (CTTSs)
ceeds through matter extracted from the inner edge
an accretion disk which is connected to the star

diagnostics that they can use, o↵er a platform to help understanding accretion plasma dynamics, with both timeand space resolution.
Up to now, in the context of accretion shocks, experiments were used to model the impact of a plasma flow
onto an obstacle using the so-called shock-tube setup as
detailed for example by Cross et al. [5]. This consists increating a plasma expansion at the rear surface of a target irradiated on its front surface by a high power laser(ILaser ⇠ 1014 W cm 2 ). This laser irradiation launchesa shock that propagates in the target, comes out at its

60. Weak and Compact Radio Emission in Early High-Mass Star Forming Regions: II. The
Nature of the Radio Sources

7 Max-Planck-Institute für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
WEAK AND COMPACT RADIO EMISSION IN EARLY HIGH-MASS STAR FORMING REGIONS: II. THE NATURE OF
8 School of Physical Sciences, University of Tasmania, Private Bag 37, Hobart, Tasmania 7001, Australia
THE RADIO SOURCES
9 INAF-Istituto di Astrofisica e Planetologia Spaziale, Via Fosso del Cavaliere 100, I-00133 Roma, Italy
1,2,3

3,10

4

5

4

6

4

ROSERO, P. H OFNER, S. K URTZ , R. C ESARONI , C. C ARRASCO -G ONZ ÁLEZ , E. D. A RAYA , L. F. RODR ÍGUEZ , K. M.
10 Adjunct V.
74,7 Lopezville Road,
8 Socorro, NM9 87801, USA.
Astronomer at the National Radio7 Astronomy Observatory,
1003
M ENTEN , F. W YROWSKI , L. L OINARD

arXiv:1905.12089v1 [astro-ph.GA] 24 May 2019arXiv:1905.12089v1 [astro-ph.GA] 24 M

6 Physics Department, Western Illinois University, 1 University Circle, Macomb, IL 61455, USA, S. P. E LLINGSEN , S. M OLINARI

1 National Radio Astronomy Observatory, 1003 Lopezville Rd., Socorro, NM 87801, USA
2 Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA

ABSTRACTIn this study we analyze 70 radio continuum sources associated with dust clumps and considered to be candidates for the earliest stages of high-mass star formation. The detection of these sources was reported by Rosero
5 INAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italyet al. (2016), who found most of them to show weak (<1 mJy) and compact (< 0.00 6) radio emission. Herein, we
6 Physics Department, Western Illinois University, 1 University Circle, Macomb, IL 61455, USA
used the observed parameters of these sources to investigate the origin of the radio continuum emission. We
7 Max-Planck-Institute für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
foundthat at least ⇠ 30% of these radio detections are most likely ionized jets associated with high-mass pro8 Schoolof Physical Sciences, University of Tasmania, Private Bag 37, Hobart, Tasmania 7001, Australia
9 INAF-Istituto
tostars,
but fore the
mostSpaziale,
compact
sources
we100,
cannotdi Astrofisica
Planetologia
Via Fossodel Cavaliere
I-00133 discard
Roma, Italy the scenario that they represent pressure-confined
10 Adjunct Astronomer at the National Radio Astronomy Observatory, 1003 Lopezville Road, Socorro, NM 87801, USA.
HII regions. This result is highly relevant for recent theoretical models based on core accretion that predict thefirst stages of ionization from high-mass stars
to be in the form of jets. Additionally, we found that properties
ABSTRACT
suchInasradio
luminosity
a functionof thebolometricluminosityof ionized
jetsfrom low and high-mass
thisthestudy
we analyze
70 radioascontinuum
sources
associatedwith dust
clumps and consideredto becandistarsdates
areforextremely
Ourdata improve
uponofprevious
studiesby providing
the earliest well-correlated.
stages of high-mass starformation.
The detection
these sources
was reported
by Rosero further evidence of a00
et al. (2016),
whoof them to show(<1 mJy) and compact (< 0. 6) radio emission. Herein, we
commonoriginforfoundjetsmost
independently
ofweakluminosity.
used the observed parameters of these sources to investigate the origin of the radio continuum emission. We
Keywords:
formationtechniques:
high sensitivity
techniques:interferometricfound thatIonizedat least ⇠Jets
30% –ofstars:
these radio
detections– aremost likely ionizedjets associated–withhigh-mass pro3 Physics Department, New Mexico Tech, 801 Leroy Pl., Socorro, NM 87801, USA

4 Instituto de Radioastronomı́a y Astrofı́sica, Universidad Nacional Autónoma de México, Morelia 58090, México

tostars, but for the most compact sources we cannot discard the scenario that they represent pressure-confined
HII regions. This result is highly relevant for recent theoretical models based on core accretion that predict thefirst stages of ionization from high-mass stars to be in the form of jets. Additionally, we found that properties
1. INTRODUCTION
such as the radio luminosity as a function of the bolometricluminosity of ionized jets from low and high-massstars are extremely well-correlated. Our data improve upon previous studies by providing further evidence of aYoung high-massstarsfor(M
8 M ) probedin cm-wavelength interferometric studies typically appear as fairly bright (fluxcommon origin
jets independentlyof luminosity.
densities of ⇠Keywords:
few mJyIonized
to Jy)Jets
regions
ionizedgas that areto their size and emission measure, e.g., compact,– stars: offormation– techniques:
highclassified
sensitivity –according
techniques: interferometricultracompact (UC), and hypercompact (HC) HII regions (e.g., Kurtz 2005). It is generally thought that once nuclear burning
has begun the star produces enough UV radiation to photoionize the surrounding gas. However, theories of the earliest stages
1. INTRODUCTION
remain poorly constrained by observations mainly
due to the characteristics of the regions where they are born, which are highly
Young high-mass stars (M8 M ) probed in cm-wavelength interferometric studies typically appear as fairly bright (fluxdust-obscured, distant (& 1 kpc) regions that undergo rapid evolution, and they reach the zero-age main sequence (ZAMS) while
densities of ⇠ few mJy to Jy) regions of ionized gas that are classified according to their size and emission measure, e.g., compact,
still heavily
accreting.
Inhypercompact
fact, an evolutionary
sequencefor 2005).
high-mass
stars has
not thatyetoncebeennuclear
establishedultracompact(UC), and(HC) HII regions(e.g., Kurtz
It is generally
thoughtburning (e.g., Sánchez-Monge
has begunTan
the starproducesenoughUV radiation
to photoionize
the hassurroundinggas. However,theoriesof the earliest stages
et al. 2013a;
et al.
2014),
althoughsignificant
progressbeen achieved
on bothobservational
and theoretical fronts (e.g.,
by observations
mainlydueof
to objects
the characteristicsof the regions
theyevolution
are born, whichhighlyMotteremain
et al. poorly
2018).constrained
The identification
and
study
in the earlystageswhereof theirwillarehelp
us to discriminate among
dust-obscured, distant (& 1 kpc) regions that undergo rapid evolution, and they reach the zero-age main sequence (ZAMS) while
proposedmechanisms
theirformation;sequence
the twomain scenarios
being
core
accretion
scaled-up version of low-mass
still heavily
accreting. forIn fact,
an evolutionary
for high-massstars has not
yet beenestablished(e.g.,(i.e.,Sánchez-Monge

DUST POLARIZATION TOWARD EMBEDDED PROTOSTARS IN OPHIUCHUS WITH ALMA. III. SURVEY

61. Dust Polarization Toward Embedded Protostars
OVERVIEW in Ophiuchus with ALMA. III. Survey
DUST POLARIZATION TOWARD EMBEDDED PROTOSTARS IN OPHIUCHUS WITH ALMA. III. SURVEY

1
OVERVIEW
Overview
Sarah I. Sadavoy1†,2 , Ian W. Stephens1 , Philip C. Myers, Leslie Looney3 , John Tobin4 , Woojin Kwon5,6 , Benoı̂t
7

8

9

10,11

1
1
4
, Dominique, ThomasHenningHennebelle
Sarah I. Commerçon
Sadavoy1†,2 , Ian
W. StephensSegura-Cox, Philip C. Myers, Leslie
Looney3,, Patrick
John Tobin, Woojin Kwon,5,6 , Benoı̂t7
8
9(Dated: Received; accepted)
Commerçon , Dominique Segura-Cox, ThomasHenning , Patrick Hennebelle10,11 ,DraftversionSeptember
9, 2019(Dated:Received; accepted)

Draft version September 9, 2019

ABSTRACTABSTRACT
We present
0.25
resolution
(35
au)
ALMA
1.3
mm dust polarization observations for 37 young stellar
00
We present 0.25 resolution (35 au) ALMA 1.3 mm dust polarization observations for 37 young stellar
objectsobjects(YSOs)
in themolecular
dataencompass
encompass
all theembedded
protostars(YSOs)
in Ophiuchus
the Ophiuchus
molecularcloud.
cloud. These
These data
all theembedded
protostars
in the incloud
and several
FlatFlatandandClass
producethe
thelargest,largest,homogeneous
the cloudand several
ClassIIIIobjects
objects toto produce
homogeneous
studystudyof dustof dust
polarizationon
disk
scales
to
date.
The
goal
of
this
study
is
to
study
dust
polarization
morphologies
polarization on disk scales to date. The goal of this study is to study dust polarization morphologies
down
to scales.
disk scales.
that
14/37(38%)(38%) of thearearedetectedin polarization
down todisk
We We
findfindthat
14/37
the observed
observedYSOs
YSOs
detectedin polarization
atoursensitivity.
Nine
of
these
sourceshave
uniform
polarization
anglesandfoursourceshave haveat our sensitivity. Nine of these sources have uniform polarization angles and four sources
azimuthalpolarization
structure.
We
find
that
the
sourceswithuniform
polarization
tend
to
have
azimuthal polarization structure. We find that the sources with uniform polarization tend to have
inclinations(> 60) thanthosewith
with azimuthal
azimuthal polarization
(<(<
60 60
). Overall,
the majority
steepersteeper
inclinations(> 60) thanthosepolarization). Overall,
the majority(9/14) of the detected sources have polarization morphologies and disk properties consistent with
(9/14)dustof thedetected processes
sources havepolarization
morphologies
andsources
disk mayproperties
consistentself-scatteringin opticallythick disks.
The remaining
be instead
tracing withdust self-scattering
processes
in
opticallythickdisks.
The
remainingsourcesmaybeinsteadmagnetic fields. Their inferred field directions from rotating the polarization vectors by 90 are mainlytracing
magnetic
fields.
inferredfield
from rotating
thetoroidal
polarization
vectors bytoward
90 arepoloidalor Theirhourglassshaped.
Wedirections
find no evidenceof a strong
field component
anymainlyof ourdisks. For the
23 YSOs
areno
undetectedroughly halfthem have 3-sigma
poloidalor hourglass
shaped.
Wethatfindevidenceinofpolarization,a strong toroidal
fieldofcomponent
toward anyof <232%.
These
also tend toinhave
inclinationsroughly< 60 andare generallyof our upperdisks.limits
For theYSOs
thatsources
are undetected
polarization,
halftheyof themhave 3-sigmacompact.
Since
lower
inclination
sources
tend
to
have
azimuthalpolarization,
these
YSOs
may generallybeupper limits of < 2%. These sources also tend to have inclinations < 60 and they are
undetectedinpolarizationdue
tounresolved
polarization
structure
withinourbeam.
Weproposecompact. Since lower inclination sources tend to have azimuthal polarization, these YSOs may bethat disks with inclinations > 60 are the best candidates for future polarization studies of dust selfundetectedin polarization
duewillto generally
unresolved
structure
withinbeam.
Weproposescatteringas these systems
showpolarization
uniform polarization
vectors
thatourdo notrequirevery
that disks
inclinations
60 release
are thecandidates
for futureimages
polarization
studies
ofwithdust selfhigh withresolution
to resolve.>Wethebestcontinuum
and polarization
for all thesourcesscatteringasthesesystemswill
generallyshow
uniform
polarization
vectorsthat
donot
requirevery
this publication. Data from the entire survey can be obtained from Dataverse.
high resolution to resolve. We release the continuum and polarization images for all the sources withthis publication. Data from the entire survey can be obtained from Dataverse.

iv:1909.02591v1 [astro-ph.SR] 5 Sep 2019

909.02591v1 [astro-ph.SR] 5 Sep 201900

1. INTRODUCTION

Interstellar magnetic fields in molecular clouds aremost often characterizedthrough sensitive observations
1. INTRODUCTION
of dust polarization. The polarization signature is atInterstellar
fieldsdustin grains
molecular
clouds alignaretributedmagnetic
to non-sphericalthat partiallymost often
observations
with characterized
their short axesthroughparallel sensitive
to an external
magnetic
due to radiative
torques(RATs) fromanof dust fieldpolarization.
Thealignment
polarization
signature
is atradiation dust
field (Andersson
al. 2015). alignThus,
tributedanisotropic
to non-sphericalgrains thatetpartiallydust shortpolarization
is expected
the morphology
with theiraxes parallelto to
an trace
external
magneticoftheplane-of-sky
magnetic
field,
withthepolarization
field due to radiative alignment torques (RATs) from ananisotropic† radiation
field (Andersson et al. 2015). Thus,
Hubble Fellow
1 Harvard-Smithsonian Center for Astrophysics, 60 Garden
dust polarization is expected to trace the morphology
Street, Cambridge, MA, 02138, USA
2 Departmentof the plane-of-sky
magnetic
field,
with thepolarization
for Physics,
Engineering
Physics
and Astro-

vectors parallel to the field direction from dust extinction and perpendicular to the field direction from thermal dust emission.
vectors
thepolarization
field direction
One keyparallel
goal of to
dust
studiesfrom
is to dust
trace extinction and field
perpendicular
to thefrom thermagnetic
structure fromthe field
scalesdirectionof molecularmal dust
emission.
clouds(⇠ 10pc) to the scales of planet-forming disks
One
key
goal
of dustdust
polarization
is to trace(. 100 au). In particular,
polarization studies
observations
atearly stages
the star formation
processare ofnecesmagnetic
fieldof structurefrom thescalesmolecularsary
tounderstand
the
role
of
magnetic
fieldsin
both
star
clouds (⇠ 10 pc) to the scales of planet-forming disks
anddiskau).
formation.
Numerous
observationsof embed(. 100
In particular,
dust
polarization
observations
ded young stars, hereafter protostars, show polarization
at early stages of the star formation process are neceson the scales of their surrounding dense cores or densesary to understandthe etrolemagnetic
in both starenvelopes(e.g., Matthews
al.of
2009;
Dotson fields
et al. 2010;
and etdisk
formation.
of embedHull
al. 2014;
GalametzNumerous
et al. 2018).observations
These detections

Lund Observatory, Box 43, Sölvegatan
27, SE-22100 Lund,of
Sweden,e-mail:schulik@astro.lu.se
radiation-hydrodynamic
simulations
gas
accretion:
62. Global
3D
radiation-hydrodynamic
simulationsofgas
accretion: The opacity dependent
Max-Planck Institut für Astronomie, Königsstuhl 17, 69117 Heidelberg, Germany
Laboratoire
Lagrange,
UMR7293,planets
Universitéde la Côte d’Azur, Boulevardde la Observatoire, 06304 Nice Cedex 4, Franceof Saturn-masspacity growthdependent
growthof Saturn-massplanets
1
2
3

Received ...

M. Schulik,1 A. Johansen,1 B. Bitsch,2 E. Lega3

ABSTRACTy, Box 43, Sölvegatan 27, SE-22100 Lund, Sweden, e-mail: schulik@astro.lu.se
tut für Astronomie,
69117andHeidelberg,
TheKönigsstuhl
full spatial 17,
structure
temporalGermany
evolution of the accretion flow into the envelopes of growing gas giants in their nascent discs
ange, UMR7293,isUniversitéde la Côted’Azur, Boulevardde la Observatoire,
06304 Nice
Cedexapproach
4, Franceof computing the formation of gas giants byonly accessible
in simulations.
Such simulations
are constrainedin theirdimensionality, resolution, consideration of self-gravity, energy treatment and the adopted opacity law. Our study explores how anumber of these parameters a↵ect that measured accretion rate of a Saturn-mass planet. We present a global 3D radiative hydrodynamics framework using the FARGOCA-code. The planet is represented by a gravitational potential with a smoothing length at thelocation of the planet. ABSTRACT
No mass or energy sink is used, instead luminosity and gas accretion rates are self-consistently computed.
We find that the gravitational smoothing length must be resolved by at least 10 grid cells to obtain converged measurements of thecture and temporal
the accretion
growinggas giantsenvelopesin their nascentdiscs with previous studies, and continue togasevolution
accretionofrates.
Secondly,flow
we intofind thegasenvelopes
accretion of
rates
into planetarycompatiblen simulations. Suchsimulations
in ourtheirplanetary
approachenvelopesof computing
the formationof gasgiantsby gas accretion rates are formally in
explainthose viaaretheconstrained
structure ofand their
luminosities.
Ourmeasuredolution, considerationof self-gravity,
energy treatment
and theopacity entropy
law. Ourloss
study
how a over the simulation time-scale, but
the stageof Kelvin-Helmholtz
contraction
dueadopted
to the modest
thatexplores
can be obtained
ameters a↵ect thatrate of a Saturn-mass
We duringpresentlate
a global
3D radiativehydrodyourmeasured
accretion accretion
rates are compatible
with thoseplanet.
expected
run-awayaccretion.
Our detailed simulations of the gas flow into
using the FARGOCA-code.
is represented
a gravitational
potential
a smoothingthe
lengthat thethe envelopeTheof planeta Saturn-massplanetbyprovides
a frameworkforwithunderstanding
generalproblem of gas accretion during planet
et. No mass or energy
sink
is
used,
insteadluminosity
andgasaccretion
rates
areself-consistently
computed.
formation and highlights circulation features that develop inside the planetary envelopes. Those circulation features feedback into thevitational smoothinglengthmust be andresolved
by atfurther
least 10
grid cells toconverged
the of the envelope.
envelope
energetics
can have
implications
forobtaintransporting
dustmeasurements
into the innerof
regions
Secondly, we find gas accretion rates into planetary envelopes compatible with previous studies, and continue toKeywords.envelopes
giant planet– simulations– radiationgas
hydrodynamics
e structure of ourplanetary
andformation
their luminosities.
Our measured
accretion rates are formally in-Helmholtz contraction due to the modest entropy loss that can be obtained over the simulation time-scale, but
are compatible with those expected during late run-away accretion. Our detailed simulations of the gas flow into
aturn-mass planet provides a framework for understanding the general problem of gas accretion during planet
1. Introduction
can destabilize, become turbulent and thus influence further discights circulation features that develop inside the planetary envelopes. Those circulation features feedback into theevolution via changing the strength of turbulence or regulating
and can have further implications for transporting dust into the inner regions of the envelope.

their own depth (Hallam & Paardekooper 2017). The gap structem as well as in extrasolar planetary systems. As the most ture also feedbacks on the planet. Gaps slow planetary migration
massive planetary class, their gravity determines the evolution through the parent disc (Lin & Papaloizou 1986) and both gapof planetary systems after their formation (Davies et al. 2014). depth and migration speed can a↵ect accretion independently
cangiant
destabilize,
becometurbulentthus influence(Dürmann& Kleyfurther
2017; disc
Kanagawa et al. 2018). Migrating gas
Ever since the first discovery of gas
exoplanets(Mayor& andevolution via changing the strength of turbulence or regulating
Queloz 1995), their occurence rates and correlations with host giants will also excite the orbits of other planets in the systemown depth (Hallam & Paardekooper 2017). The gap strucportant classplanets inthebeenSolarmapped
Sys- theirstar ofproperties
have
observationally. It is clear now (Raymond et al. 2016) and change their migration speed (Masturealso
on the planet. Gaps slow planetary migration
asolar planetarysystems.
Asprimarily
the mostaround stars feedbacks
that gas giants
orbitthat are rich in heavy set & Snellgrove 2001). They can further influence the evoluthrough the parent disc (Lin & Papaloizou1986) throughand bothtrailing
gap swarms of pebbles that accumution of systems, their gravity
determines
the1997;
evolution
elements(Gonzalez
Fischerdepth& Valenti
2005;
Mayor
et
al.
and migration speed can a↵ect
late ataccretion
their gapindependently
edge and form seed locations for the growth ofter their 2011);
formation
et al. 2014).
this(Davies
is particularly
pronouncedforgas
giantsoneccen(Dürmann
&
Kley
2017;
Kanagawaetal.
2018).
Migrating2018). It is thus an important priority
overy of tricgas giant& from planet-planet scattering in new planets (Ronnet et al.gas
orbitsexoplanetsthat likely(Mayor
resulted

Gas giants
form an– importantclass of planets in the Solar Sysplanet formation– simulations
radiation hydrodynamics

arXiv:1909.06843v1 [astro-ph.GA] 15 Sep 20199

Chalmers University of Technology, Onsala Space Observatory, 43992, Onsala, Sweden; 10 Department of Astronomy,of Virginia,
PO Molecules
Box 400325, Charlottesville,
VA 22904, Regions
USA; 11 National
Radio
Astronomy Observatory,
63. University
Complex
Organic
in Star-Formingof theMagellanic
Clouds12
520 Edgemont Rd, Charlottesville, VA 22903, USA;
Astronomisches Rechen-Institut, Zentrum für Astronomie der
⇤,†,†
¶
k
Universität
Heidelberg,
Heidelberg
Germany;
Departmentof PhysicalMarta
Sewiło,Steven69120
B. Charnley,
Peter
Schilke,13§ Vianney
Taquet,Joana Science, Graduate School of Science,
14?
#,@r,††NAOJ, National Institutes of Natural
Osaka
Prefecture
University,
Osaka599-8531,
Japan;4 Remy
ChileIndebetouw,
Observatory,
M. Oliveira,Takashi
Shimonishi,
Eva Wirström,
15
Sciences,
Osawa,
Mitaka,181-8588,
Japan;
National
Astronomical Observatory of Japan, 2-21-1 Os‡‡?
¶¶
Jacob2-21-1
L. Ward,Jacco
Th. Tokyo
van Loon,
Jennifer
Wiseman,
Sarolta16awa, Mitaka,
Max-Planck-Institutfür Radioastronomie,
Auf dem Hügel 69 D-53121 Bonn,§§,kkTokyo 181-8588, Japan;§§??
##
Zahorecz,
Toshikazu
Onishi,
Akiko
Kawamura,
C.-H.
Rosie
Chen,
17
Germany; Nagoya University,
School of Science, Furo-cho, Chikusa-ku,
Nagoya, JP 464-8602@@§

Regions of the Magellanic Clouds

Yasuo Fukui,

and Roya Hamedani Golshan

E-mail contact: marta.m.sewilo at nasa.gov†CRESSTand Small
Exoplanets
and Stellar
Astrophysics
Laboratory,
NASA dwarf
GoddardSpace
The LargeIIand
Magellanic
Clouds(LMC and
SMC), gas-richcompanionsof the Milky Way, are the nearest
FlightCenter,Greenbelt,
MD
20771,
USA
laboratories for detailed studies on the formation and survival of complex organic molecules (COMs) under metal poor
‡Department of Astronomy, University of Maryland, College Park, MD 20742, USA
conditions.
To date, only methanol, methyl formate, and dimethyl ether have been detected in these galaxies – all¶Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771,
three toward two hot cores in the N113 star-forming region in the LMC, the only extragalactic sources exhibitingUSA
complexhotcore
chemistry.
We
describea small and diverse sample of the LMC and SMC sources associated with
§I. Physikalisches Institut der Universität zu Köln, Zülpicher Str. 77, 50937, Köln,
COMs or hot core chemistry, and Germany
compare the observations to theoretical model predictions. Theoretical models
accounting
for the physicalconditions
andLargo
metallicity
of 5,
hot50125
molecular
cores
kINAF, Osservatorio
Astrofisico
di Arcetri,
E. FermiFirenze,
Italyin the Magellanic Clouds have been able
to broadly ?Lennard-Jones
account for the Laboratories,
existing observations,but failST5
to reproduce
Keele University,
5BG, UK the dimethyl ether abundance by more than anorderof magnitude.
discuss
prospects Sciences,
for researchin thefield of complex chemistry in the low-metallicity#Frontier
ResearchWe
Instituteforfuture
Interdisciplinary
TohokuUniversity,
environment.
The detection
COMsSendai,in theMiyagi,
Magellanic
Cloudshas important implications for astrobiology. The
Aramakiazaaoba
6-3, of
Aoba-ku,
980-8578,
Japan
metallicityof theMagellanic
is similar
to galaxies6-3,
in Aoba-ku,
the earlier
epochs of the Universe, thus the presence@AstronomicalInstitute,
TohokuClouds
University,
Aramakiazaaoba
Sendai,
Miyagi,
980-8578,
Japan
of COMs in the LMC and SMC indicates that a similar prebiotic chemistry leading to the emergence of life, as it
4Departmentof Space,
andinEnvironment,
Chalmers
Universityof Technology,
happenedon Earth,is Earthpossible
low-metallicity
systemsin the earlier
Universe.
Onsala Space Observatory, 43992, Onsala, Sweden
rDepartment of Astronomy, University of Virginia, PO Box 400325, Charlottesville, VA
22904, USA
44††National Radio Astronomy Observatory, 520 Edgemont Rd, Charlottesville,
VA 22903,
USA‡‡Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg,
Mönchhofstr. 12-14, 69120 Heidelberg Germany¶¶NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, USA§§Department of Physical Science, Graduate School of Science, Osaka Prefecture
University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
kkChile Observatory, National Astronomical Observatory of Japan, National Institutes of
Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan??National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588,
Japan##Max-Planck-Institut fu?r Radioastronomie, Auf dem Hügel 69 D-53121 Bonn, Germany@@Nagoya University, School of Science, Furo-cho, Chikusa-ku, Nagoya, JP 464-8602

iv:1909.04341v1 [astro-ph.GA] 10 Sep 2019terium 1chemistryin starless cores: full scrambling
Max-Planck-Institute for Extraterrestrial Physics (MPE), Giessenbachstr. 1, 85748 Garching, Germany
versusproton hop
e-mail:osipila@mpe.mpg.de
64. Modeling
deuteriumchemistry in starless cores: full scrambling versus proton hop
2
Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland
O. Sipilä1 , P. Caselli1 , and J. Harju2, 1Received / Acceptedr Extraterrestrial Physics (MPE), Giessenbachstr. 1, 85748 Garching, Germany
mpg.deP.O. Box 64, 00014 University of Helsinki, Finland

ABSTRACT

We constructed two new models for deuterium and spin-state chemistry for the purpose of modeling the low-temperature environment
prevailing in starless and pre-stellar cores. The fundamental diﬀerence between the two models is in the treatment of ion-molecule
proton-donationABSTRACT
reactions of the form XH+ + Y −→ X + YH+ , which are allowed to proceed either via full scrambling or via direct
proton hop, i.e., disregarding proton exchange. The choice of the reaction mechanism aﬀects both deuterium and spin-state chemistry,odels for deuterium
andthisspin-state
the purposeof modelingtheon
low-temperatureenvironmentWe applied the new models to the starless core H-MM1,
and inwork chemistry
our mainforinterest
is on
the eﬀect
deuterated ammonia.
pre-stellar cores. The fundamental diﬀerence between the two models is in the treatment of ion-molecule
severaldeuterated
forms
of ammonia
investigationslightly favors the proton hop mechanism over full++of the form XHwhere+ Y −→X + YH, which areallowedto proceed have
either been
via fullobserved.
scramblingOuror viadirectscrambling
becausetheammonia
D/H
ratiosarebetterfit
bytheformermodel,
althoughneither model can reproduce the observed
ng proton exchange. The choice of the reaction mechanism aﬀects both deuterium and spin-state chemistry,
interest is on the
on deuterated ammonia.
appliedthe newmodelsatovalue
the starlesscoreExtending
H-MM1, the proton hop scenario to hydrogen atom abstraction
NHeﬀect
ratio of We
3 (themodelspredictof ∼2).
2 D ortho-to-paraorms of ammonia
have
been
observed.
Ourinvestigationslightlyfavorstheprotonhopmechanism
reactions yields a good agreement for the spin-state abundance ratios,overbutfullgreatly overestimates the deuterium fractions of ammonia.
mmonia D/H ratios
arebetterfit
bytheformermodel,
althoughneithermodel
canreproducetheobserved
However, one can find a reasonably good agreement with the observations with this model by increasing the cosmic-ray ionizationof 3 (the models predict a value of ∼2). Extending the proton hop scenariohydrogen atom abstraction−17 toover abundance
the commonly-adopted
value of ∼10
s−1 . Wealso findthat the deuterium fractions of several other species, such as
reement for therate
spin-state
ratios, but greatly overestimates
the deuterium
fractionsof ammonia.
the byadoptedproton-donation
reaction mechanism. Whether the full scrambling or proton hop
2 CO, H2 O,
3 , are sensitive
easonably goodHagreement
withandthe CHobservations
with this tomodel
increasing
the cosmic-ray ionization−17 −1dopted value of
∼10
s
.
We
also
find
that
the
deuterium
fractionsofseveralotherspecies,suchnew
as laboratory and theoretical studies for various reacting
mechanism dominates may be dependent on the reacting system, andsensitive to theadoptedproton-donation
reactionmechanism.
Whetherthefullscramblingor
protonhop
systems are needed to constrain chemical models.

y be dependent on the reacting system, and new laboratory and theoretical studies for various reacting
strain chemicalKey
models.
words. astrochemistry – ISM:abundances – ISM:clouds – ISM:molecules – radiative transfer

ry – ISM:abundances – ISM:clouds – ISM:molecules – radiative transfer

1. Introduction

protons gives rise to two spin states where the nuclear spin wave-

protons gives rise to two spin states where the nuclear spin wavefunction
is either antisymmetric (para-H2 ; rotational quantum
functionreactions
is either antisymmetric(para-Hrotational
quantum
2 ;of
Ion-molecule
proton-donation
are
at
the
heart
n reactions are at the heart of number J = 0, 2, 4...) or symmetric (ortho-H ; Jnumber
J = 0, 2, 4...) or symmetric (ortho-H2; J = 1, 3, 5...);= 1, 3, 5...);
2
instates
the behaveinterstellar
medium(ISM)n the low-temperatureinterstellar medium chemistry(ISM) these
thesestates behave as distinct chemical species that (practically)
as distinct chemical species that(practically)
One (Herbst
particular&moleculethat is1973).
KlempererOne
particularmoleculethatiscannot be converted from one form to the other by radiationor bycannot beconverted from one form to the other by radiation or by
ns is formed
ammonia,throughwhich is suchan im-reactions
ammonia,
which
is an diﬀerence
im- inelastic
inelastic is
collisions.
The ∼170
K energy
between collisions.
theThe ∼170 K energy diﬀerence between therobing the gas temperature in the J = 0 and 1 rotational levels is an important source of chemical
portant
diagnostic
toolfor
probingthegastemperatureinthevely used for this purpose (e.g., energy in dense clouds, and allows in particular the
J =exothermic
0 and 1 rotational levels is an important source of chemical
ISM, andhas been
extensively used for this purpose (e.g., energy
ences therein).
Ammonia
is a relain dense clouds, and allows in particular the exothermic
reactional. 2017,
main Friesen
gas-phaseet
formation
andandde- references therein). Ammonia is a rela- reaction
since been
identified:formationandH+3its+ mainHD ←→H2 D+ + Hformation(5)
tivelysimpleitsmolecule
gas-phase2 + 232 K and dehermicstructionhydrogen pathways
atom abstraction+
have longsince been
its formation+
H2 D+ + H2 + 232 K(5)
3 +to proceedalso identified:in the backward
reaction nearH10
K.HD
H2 D←→
begins with the slightly endothermic
abstractionis the main hydrogen
driver of atom
deuterationin cold clouds (e.g.
+to proceedreaction(1) Rodgers & Charnley 2001). Spin-state and deuterium
chemistry also in the backward reaction near 10 K. H2 D

Max Planck
Institute forand
Astronomy,Königstuhl
17, 69117, Heidelberg,
Germany. soler@mpia.de
65. 1.
Using
Herschel
Planckobservations
to delineate
the role of magnetic ﬁelds in
Received
26 APRcloud2019 / Accepted
07 AUG 2019
molecular
structure:1909.04862v1 [astro-ph.GA] 11 Sep 2019

ABSTRACT

We present a study of the relative orientation between the magnetic field projected onto the plane of sky (B? ) on scales down to
0.4 pc, inferred from the polarized thermal emission of Galactic dust observed by Planck at 353 GHz, and the distribution of gas
column density (NH ) structures on scales down to 0.026 pc, derived from the observations by Herschel in submillimeter wavelengths,
toward ten nearby (d < 450 pc) molecular clouds. Using the histogram of relative orientation technique in combination with tools
from circular statistics, we found that the mean relative orientation between NH and B? toward these regions increases progressively
from 0 , where the NH structures lie mostly parallel to B? , with increasing NH , in many cases reaching 90 , where the NH structures
lie mostly perpendicular to B? . We also compared the relative orientation between NH and B? and the distribution of NH , which ischaracterized by the slope of the tail of the NH probability density functions (PDFs). We found that the slopes of the NH PDF tailare steepest in regions where NH and B? are close to perpendicular. This coupling between the NH distribution and the magnetic
field suggests that the magnetic fields play a significant role in structuring the interstellar medium in and around molecular clouds.
However, we found no evident correlation between the star formation rates, estimated from the counts of young stellar objects, andthe relative orientation between NH and B? in these regions.
Key words. ISM: general, dust, magnetic fields, clouds – stars: formation – Submillimetre: ISM

1. Introduction
The physical processes that regulate the formation of stars are
one of the main open subjects of research in contemporary astrophysics (for a review see McKee & Ostriker 2007; Dobbs et al.
2014; Molinari et al. 2014). Interstellar magnetic fields are along-standing candidate for the control of the star formation process (see, e.g., Mouschovias et al. 2006). Observations indicatethat in flux-freezing conditions, the interstellar magnetic fields,
gas pressure, cosmic-ray pressure, and gravity are the most important forces on the di↵use gas (Heiles & Crutcher 2005). It
is likely that magnetic fields are responsible for reducing thestar formation rate in dense molecular clouds (MCs) by a factor
of a few by strongly shaping the interstellar gas (Hennebelle &Inutsuka 2019, and references therein). However, observing themagnetic fields in and around MCs and determining their exact
influence is a difficult task.

The magnetic field strength can be assessed indirectly from the linear polarization observations using theDavis-Chandrasekhar-Fermi method (DCF, Davis 1951;
Chandrasekhar & Fermi 1953), which combines estimations of
the density, velocity dispersion, and polarization angle dispersion toward the studied regions (see, e.g., Houde et al. 2009;
Pattle et al. 2017a). An alternative to directly estimating themagnetic field strength is to statistically study the magnetic fieldorientation and its correlation with the observed column density,
NH , distribution. Recent studies of numerical simulations ofmagnetohydrodynamic (MHD) turbulence indicate that there isa relation between the statistical trends of relative orientation
between NH and B? and the initial magnetization of the MCs(Soler et al. 2013; Chen et al. 2016; Soler & Hennebelle 2017).
The observational study of this trend toward ten nearby MCs
reveals based on the Planck observations that on spatial scales
ranging from tens of parsecs to 0.2 pc, turbulence is trans-