星形成ゼミ
2016/11/18
SFN #286 6-10
工藤哲洋（長崎大）

Late veneer and late accretion to the terrestrial planets
R. Brassera,1,∗, S. J. Mojzsisb,c,1,∗, S. C. Wernerd,1 , S. Matsumurae,2, S. Idaaa Earth Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan

arXiv:1609.01785

b Department of Geological Sciences, University of Colorado, UCB 399, 2200 Colorado Avenue, Boulder, Colorado 80309-0399, USA

地球型惑星が微惑星の衝突で形成される過程において，月の強親
鉄元素に基づき，微惑星の質量や進化に対する制限を，N体計算とモンテカルロ計算で調べた．

r Geologicaland Geochemical Research, Research Center for Astronomy and Earth Sciences, Hungarian Academy of Sciences, 45 Budaö
•
H-1112 Budapest, Hungary
d The Centre for Earth Evolution and Dynamics, University of Oslo, Sem Saelandsvei 24, 0371 Oslo, Norwaye School of Science and Engineering, Division of Physics, Fulton Building, University of Dundee, Dundee DD1 4HN, UK•

地球の強親鉄元素はおおよそ1回の衝突で生じた（月形成）．

ally accepted that silicate-metal (‘rocky’) planet formation relies on coagulation from a mixture of sub-Mars siz
os and• (smaller)
planetesimals that dynamically emerge from the evolving circum-solar disc in the first few mill
レイトベニアの時（月形成の時）に火星へのコンドライト供給は
ar System. Once the planets have, for the most part, assembled after a giant impact phase, they continue to be bo
火星質量の0.06%．
tude of planetesimals
left over from accretion. Here we place limits on the mass and evolution of these plan
onstraints from the highly siderophile element (HSE) budget of the Moon. Outcomes from a combination of Nlo simulations of planet formation lead us to four key conclusions about the nature of this early epoch. First, mato lunarratio requires either that the late veneer on Earth consisted of a single lunar-size impactor striking• HSE
月形成以降，地球への微惑星衝突頻度は小さかった
5 Ga, or that it originatedfrom theimpact that created the Moon. An added complication is that analysis of luna
-6
-1
ME Myr）．冥王代の気候は考えられているよりも温暖
he Moon（<10does not preserve
convincing
evidence for a late veneer like Earth. Second, the expected chondrit
t on Marsだった可能性がある．
is 0.06 weight percent. Third, the flux of terrestrial impactors must have been low (! 10−6 M⊕ Myr−1
melting of Earth’s crust after 4.4 Ga, and to simultaneously match the number of observed lunar basins. This con Hadean eon which is more clement than assumed previously. Last, after the terrestrial planets had fully forPreprint typeset using LTEX style emulateapj v. 5/2/11

THE MASSIVE PROTOSTELLAR CLUSTER NGC6334I AT 220 AU RESOLUTION: DISCOVERY OF FURTHER
MULTIPLICITY, DIVERSITY AND A HOT MULTI-CORE
C. L. B ROGAN 1 , T. R. H UNTER 1 , C. J. C YGANOWSKI 2 , C. J. C HANDLER 3 , R. F RIESEN 4 , R. I NDEBETOUW 1,5
Accepted for publication in ApJ

ABSTRACT
arXiv:1609.07470
We present VLA and ALMA imaging of the deeply-embedded protostellar cluster NGC6334I from 5 cm
•to 原始星の星団NGC6334IをALMAとVLAを使って高分解能で観測1.3 mm at angular resolutions as fine as 0.′′ 17 (220 AU). The dominant hot core MM1 is resolved into
seven components at 1.3 mm, clustered within a radius of 1000 AU. Four of the components have brightness
した（分解能0.17秒：220AU）．
temperatures> 200 K, radii∼ 300 AU, minimum luminosities ∼ 104 L⊙ , and must be centrally heated. We
term this new phenomenon a "hot multi-core". Two of these objects also exhibit compact free-free emission! at longer wavelengths, consistent with a hypercompact HII region (MM1B) and a jet (MM1D). The spatial
kinematics of the water maser emission centered on MM1D are consistent with it being the origin of the high•velocity
bipolar molecular outflow seen in CO. The close proximity of MM1B and MM1D (440 AU) suggests a
MM1というコアは７つの構造に分かれる(1000AUの範囲にある)．
proto-binary or a transient bound system. Several components of MM1 exhibit steep millimeter SEDs indicativeof 内４つは中心に熱せられている（”hoteither unusual dust spectral properties or time variability. In addition
to resolving MM1 and the other hot coremulti-core”）．さらにそ(MM2) into multiple components, we detect five new millimeter and two new centimeter sources. Water masers
areの内の２つ（B，D）にはジェットとHII領域が付随し，protodetected for the first time toward MM4A, confirming its membership in the protocluster. With a 1.3 mm
brightness temperature of 97 K coupled with a lack of thermal molecular line emission, MM4A appears to bea highly
optically-thick 240 L⊙ dust core, possibly tracing a transient stage of massive protostellar evolution.
binaryが示唆される．
The nature of the strongest water maser source CM2 remains unclear due to its combination of non-thermal
continuum and lack of dust emission.
! radio
Subject headings: stars: formation — infrared: stars — ISM: individual (NGC6334I) — radio continuum: ISM– submillimeter: ISM•

その他，MM2などもいくつかの構造に分解される．MM4Aから
1. INTRODUCTION
disks, particularly in the context of binary and multiple sys水メーザーが観測されたので，原始星の星団のメンバーと確認さ
tems. These observations must be undertaken at wavelengths
Massive star formation is a phenomenon of fundamental
long enough to penetrate the high column of obscuring dust.
importanceれた．
in astrophysics, but our understanding of thisprocess is hampered by the heavy extinction and large distances to the nearest sites. Over the past decade, several

The NGC6334 region, known as the Cat’s Paw Nebula, contains multiple sites of high mass (M∗ >8 M⊙ ) star formation(Straw & Hyland 1989; Persi & Tapia 2008; Russeil et al.

NGC6331Iの中心部
The Massive Protocluster NGC6334I

MM1

8Brogan et al.

5

F IG . 4.— Sequence of source fitting for MM1 with all images shown on the same color stretch. Panel a) raw image; b) raw image after removing three
approximate Gaussians (denoted by their half-power contours) in order to fit for components C, E, F and G; c) raw image after removing the fitted components
for C, E, F and G leaving the emission from A, B and D; d) same as C after removing the final fit for B; e) the total model; f) the residual between the raw image
and the total model.

10メーザ源を重ねた

Brogan et al.

F IG . 2.— Zoomed view of the central 10′′ of NGC6334I, with the colorscale showing the (a) 1.5 cm, (b) 7 mm, (c) 3 mm, and (d) 1.3 mm images at their native
resolutions (see beams in lower right corner of each panel). On each panel, a single white 7 mm contour is shown for reference, at a contour level 0.6 mJy beam−1(4σ). For previously known sources (labeled in cyan) that are now resolved into multiple components, the components are labeled alphabetically in orange. As
in Fig. 1, newly discovered sources are labeled in magenta. Only sources detected at the wavelength shown in colorscale are labeled in panels (a), (b), and (c).
Panel (c) also shows the locations of 22 GHz H2 O masers as black + symbols (see § 3.3) and panel (d) shows the locations of 6.7 GHz (Class II) CH3 OH masers
as magenta × symbols (see § 3.4).

the most confused emission toward the center of MM1 using three Gaussian components to represent MM1A, MM1B,
and MM1D (the fitted 7 mm positions and sizes of components MM1B and MM1D were used in this initial guess). The
resulting residual image (shown in Fig. 4 as "Subtract A, B,
D") was then used to fit the now less-confused emission from
MM1C, MM1E, MM1F, and MM1G with single component
Gaussians. The fitted parameters for MM1C, MM1E, MM1F,
and MM1G were then in turn subtracted from the original im-sion of MM1A, MM1B, and MM1D. An estimate for the
1.3 mm emission from MM1B was then extrapolated from thewell constrained 7 mm fit for this source (see Table 2) using
a spectral index of 3.05 (see Fig. 3), and subtracted from the"Subtract C, E, F, G" residual image. This left a residual image ("Subtract B, C, E, F, G") with only emission from MM1A
and MM1D, now spatially distinct, from which fits were obtained for these two components. Subtracting the resulting
fitted parameters for MM1A and MM1D from the "Subtract

F IG . 5.— The locations of the H2 O masers are shown on zoomed 1.3 mm images (greyscale) f
In each panel the 311 H2 O masers are over-plotted as color coded + symbols. The velocity colo
km s−1 (color-coded green), the average velocity for MM1 found by Zernickel et al. (2012). On

矢印は双極分子流の方向−1

Ambipolar diffusion regulated collapse of filaments threaded byperpendicular magnetic fields
C. A. Burge1 , S. Van Loo1 , S. A. E. G. Falle2 , and T. W. Hartquist1
16879v1 [astro-ph.GA] 22 Sep 2016

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•

School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK

arXiv:1609.06879

Received date; accepted date

磁場に垂直に貫かれたフィラメント状分子雲が ambipolar
ABSTRACT
diﬀusionのために中心部にコアを形成する数値シミュレーショ
Context. In giant molecular clouds (GMCs), the fractional ionisation is low enough that the neutral and charged particles are weakly
coupled. A consequence of this is that the magnetic flux redistributes within the cloud, allowing an initially magnetically supportedン（2次元並進対称，等温，MHD，adaptivemesh）．
regionto collapse.
Aims. We aim to elucidate the eﬀects of ambipolar diﬀusion on the evolution of infinitely long filaments and the eﬀect of decaying
turbulenceon that evolution.
Tomisaka(2014) の平衡解を初期条件．
Methods. First, in ideal magnetohydrodynamics (MHD), a two-dimensional cylinder of an isothermal magnetised plasma with initially

uniform density was allowed to evolve to an equilibrium state. Then, the response of the filament to ambipolar diﬀusion was followed
using an adaptive mesh refinement multifluid MHD code. Various ambipolar resistivities were chosen to reflect diﬀerent ratios of
Jeans length to ambipolar diﬀusion length scale. To study the eﬀect of turbulence on the ambipolar diﬀusion rate, we perturbed theequilibrium filament with a turbulent velocity-7
field quantified by a rms sonic Mach number, Mrms , of 10, 3 or 1.
Results. We numerically reproduce the density profiles for filaments that are in magnetohydrostatic and pressure equilibrium with
their surroundings obtained in a published model and show that these equilibria are dynamically stable. If the eﬀect of ambipolar-8 these filaments lose magnetic support initiating cloud collapse. The filaments do not lose magnetic flux.
diﬀusion is considered,
Rather the magnetic flux is redistributed within the filament from the dense centre towards the diﬀuse envelope.
The rate of the collapse is inversely proportional to the fractional ionisation and two gravitationally-driven ambipolar
diﬀusion regimesneutralion
for the collapse are observed as predicted in a published model. For high values of the ionisation coeﬃcient, that is X ≥ 10−7 , thegas is strongly coupled to the magnetic field and the Jeans length is larger than the ambipolar diﬀusion length scale. Then thecollapse is governed by magnetically-regulated ambipolar diﬀusion. The gas collapses at velocities much lower than the sound speed.
For X ! 10−8 , the gas is weakly coupled to the magnetic field and the magnetic support is removed by gravitationally-dominatedambipolar diﬀusion. Here, neutrals and ions only collide sporadically, that is the ambipolar diﬀusion length scale is larger than theJeans length, and the gas can attain high collapse velocities.
When decaying turbulence is included, additional support is provided to the filament. This slows down the collapse of the filament
even in the absence of a magnetic field. When a magnetic field is present, the collapse rate increases by a ratio smaller than for the
non-magnetic case. This is because of a speed-up of the ambipolar diﬀusion due to larger magnetic field gradients generated by the
turbulence and because the ambipolar diﬀusion aids the dissipation of turbulence below the ambipolar diﬀusion length scale. The

電離が強い（X > 10 ) とゆっくりとしたコア形成，電離が弱いp（X < 10 ）と速くコアが形成される．
⇢i = 30X ⇢n
乱流（散逸する）があるとコア形成はよりゆっくりとなる．

pled toightenin thehat, innt thanacrossollapsed. Therocessed amen, we
ainder

初期条件の密度（色）と磁力線(Tomisaka 2014)

A&A proofs: manuscript no. AA201629039
最大密度の時間変化

is given by
tφ =

νﬀ tﬀ
χK
≈ 2.141.4
πG

where νﬀ = tﬀ /tni isthe average collisionthat isionisation fraction atdiscollapse
in- of filaments threaded by perpendicular magnetic fields
tion is given by χ =anel ofproportional to X if
cal. As
oupled to
free-fall time. Usinghe dystraighten
we find tφ ≈ 125tﬀ,Sadients
ent in there- in≈ 1.25tﬀ,S for X = 1
teralthat,rrent
staticthanfactor of two with tρ,theS acrossuseplain the near-propo
6. Normalised density contours, ρ/ρS , for X = 10−8 (blue), X =hecollapse
Os- Fig.
−7−6
10 (red) and X = 10 (green). The top panel shows the density confilament. However,than Thea figuration for a central density of ≈ 250ρ , while the bottom shows it
peed.
S
break down at someely
de- for ≈ 1000ρS . The contour line show normalised densities of 1, 3, 10,
d process
密度が1000倍に成長した時の密度と磁力線
cannot exceed the fr
nated am- 30, 100 and 300.
riven, weportant
mum collapse times
A&A proofs: manuscript no. AA201629039
emainder
最大密度の時間変化（乱流ありM=10）
ament
the magnetic flux su
ollapse 密度
ues to zero and we fithat isehs,magEq. 12, we expect th
ment
is ininitial
Bailey & Basu (201m panel ofg. 5b).
ntical. As
tion fraction for theament.
rt, the dybility analysis shows
he engradients
to-flux ratios equiva
aroundentral reespethe average ion-neu
earstatic00ρS , thethe free-fall collapse
Fig. 6. Normalised density contours, ρ/ρS , for X = 10−8 (blue), X =ordifd the Os磁力線
This break is als
10−7 (red) and X = 10−6 (green). The top panel shows the density conlid thanfor a figurationore
for a central density of ≈ 250ρS , while the bottom shows ittion of gas and the m
atelyws
thede- for ≈ 1000ρS . The contour line show normalised densities of 1, 3, 10,
hmic todensity, ρ/ρS , of the equilibrium configuration for the models listed in Table 1. The density range is from 0.1 to7 show the density p
mass
30, 100 and 300.
nd
C3c
which
have
a
maximum
density
of
1000
and
300,
respectively.
Thedashedlines
showcontourlines
fordensity
X = 10−6 , 10−7 andmportant
is col30,
50, 100, 200, 300 and 500. The magnetic field lines are shown by the solid lines.
filamentof 250ρS and 1000ρ
renorrnstancollapse
at diﬀerent times fo
then0ρ
to magbe
to represent an insta
and leads
a denser fila≈ 32 with ρS = pext /T 0 the surface causes the cloud to lose magnetic flux Fig.
Sinitial
itsonly
5. (a)toNormalised
central density, ρ/ρS as a function of time for
1/2
orment centre than expected from its initialconditions.
ithin≈ 5tﬀ,S (where tﬀ,S = (1/4πGρS )Fig. 5b).
ambipolar
diﬀusion regulated collapse of model C3b. (b) Ratio of line (1000ρS ) phase of th
ample
uated
with
the
surfacedensity).
Contrary
filament.
Figure 2 shows the equilibrium density
and magnetic
fieldwith the black dot the value of the equilibrium the profiles and field
mass
line
mass
bution.
Fig. to10.critical
Similarfigureas Fig. 5, but with a turbulent velocity field ofion,
dsthetheen-filament does not oscillate as it configuration for the models listed in Table
1.
Comparingthese
profile.
Thesquaresshow
the ratio when
the Thecentraldensityis 1000 ent collapse rates, inapse isM= 10 added to the equilibrium
filament.
purpleline showsrms

A gas density drop in the inner 6 AU of the transition disk aroundthe Herbig Ae star HD 139614
Further evidence for a giant planet inside the disk?
A. Carmona1,2,3,?,?? , W.F. Thi4 , I. Kamp5 , C. Baruteau1 , A. Matter6 , M. van den Ancker7 , C. Pinte8,9 , A. Kóspál2 , M.
Audard10 , A. Liebhart11 , A. Sicilia-Aguilar12 , P. Pinilla13 , Zs. Regály2 , M. Güdel11 , Th. Henning14 , L.A. Cieza15 , C.
Baldovin-Saavedra11 , G. Meeus3 , and C. Eiroa3,16
Université de Toulouse, UPS-OMP, IRAP, 14 avenue E. Belin, Toulouse, F-31400,
France e-mail:arXiv:1609.06708
andres.carmona@irap.omp.eu
2
Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, P.O. Box 67, H-1525
Budapest, Hungary
3
Departamento de Fı́sica Teórica, Universidad Autónoma de Madrid, Campus Cantoblanco, 28049, Madrid, Spain
4
Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse 1, D-85748 Garching bei München, Germany
5
Kapteyn Astronomical Institute, Postbus 800, 9700 AV, Groningen, The Netherlands
6
Laboratoire Lagrange, Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Boulevard de l’Observatoire, CS 34229,
06304 Nice Cedex 4, France.
7
European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany
8
UMI-FCA, CNRS/INSU, France (UMI 3386), and Dept. de Astronomı́a, Universidad de Chile, Santiago, Chile
9
Univ. Grenoble Alpes, IPAG, 38000, Grenoble, France; CNRS, IPAG, 38000, Grenoble, France
10
Department of Astronomy, University of Geneva, Ch. d’Ecogia 16, 1290 Versoix, Switzerland
11
University of Vienna, Department of Astronomy, Türkenschanzstrasse 17, 1180, Vienna, Austria
12
SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS, UK
13
Leiden Observatory, Leiden University, P.O. Box 9513, 2300RA Leiden, The Netherlands
14
Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany
15
Núcleo de Astronomı́a, Facultad de Ingenierı́a, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile
16
Unidad Asociada Astro-UAM/CSIC

6708v2 [astro-ph.SR] 17 Oct 2016

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Herbig Ae 星 HD 139614 の円盤をCOの回転振動輝線で観測した（ESO/VLT CRIRES）．
HD 139614 の円盤の内側（2.3-5.3AU）にはダストの分布にギャップがあることが知られているが，ガス(CO)にはギャップはなかった．ただし，ガス表面密度は内側（<6AU）で極端に少な
く，表面密度の分布は半径の増加関数であった．
ABSTRACT
Context. Quantifying the gas surface density inside the dust cavities and gaps of transition disks is important to establish their origin.
Aims. We seek to constrain the surface density of warm gas in the inner disk of HD 139614, an accreting 9 Myr Herbig Ae star witha (pre-)transition disk exhibiting a dust gap from 2.3±0.1 to 5.6±0.3 AU.
その結果，4AUあたりに木星質量程度の惑星が示唆される．
Methods. We observed HD 139614 with ESO/VLT CRIRES and obtained high-resolution (R⇠90 000) spectra of CO ro-vibrationalemission at 4.7 µm. We derived constraints on the disk’s structure by modeling the CO isotopolog line-profiles, the spectroastrometricsignal, and the rotational diagrams using grids of flat Keplerian disk models.
Results. We detected = 1 ! 0 12 CO, 2!1 12 CO, 1!0 13 CO, 1!0 C18 O, and 1!0 C17 O ro-vibrational lines. Lines are consistent10

CO p=1-0

26

10

10
3

24

102

10 3

102

1022

103

104

24

1022

ラインの形を再現出来ない（上の図：v=8km/s のあたり）．
10 3

1020

1020

4

600

100

C18O p=1-0

1026

200

1026

10

10

21

300 400
Tgas [K]

500

600

10
10

10
-1
-2

100

R
R [A

12
Line
Flux Density
Cumulative
Flux opC

0.4800100 16200
300 400
0.3600Tgas [K]500

1000.015 41080
0.01010260

600

CO P(9)13

CO R(4)

C18O R(6)

0

10
40
0.005
10-2
20
00.00010-4
1
1 1

10
R [AU]R [AR

12Cumulative
Flux 13C
CO Density
P(9)
Flux

[erg s cm sr ]100
0.80.015
0.6
80

-1

ln(F/iguAul)[erg s-1 cm-2 sr-1]

12

13

18

ln(F/iguAul)%

12

m-2 sr-1]

only two line fluxes are available and no reliable estimate of the

-2

0.4

600.010

0.2

40
0.005
-0.2
20

-1

o

ガス表面密度が内側（<6AU）で少なくなるモデルがベストフィット．
%[K][erg s-1 cm-2 sr-1]

2010
gas0.0=
1 1

The numbers inside the contour indicate n-times the value of13the[erg s-1 cm-2 sr-1]

NH [cm-2]0.120012
Gas temperature
Flux Density
CO P(9)-2 18

Gas column density [g cm10]
24

12
CO
R(4)
2 Gas temperature
Flux minimum
Density 12CO P(9)Cumulative Flux 12CO (P9) Flux Density
CO depth
Line optical
.
0
800
0.015
10
0.4
100
-68
b)
red
10
12
1023
CO P(9)
104
10-1
80
22
0.3
-69
13
10
600
-2
CO R(4)10210.010 2
60
18
10
-3
C
O R(6)
10
Fig. 5. Line-profiles predicted for models
with a gap in10the inten0.2
-70
20
10
-4
40
400
10 distribusity distribution: a) line-profiles 10
expected
for a intensity
19
-5
0.1
100 -714.2. Average temperatureand column density
10
20
0.005
182.5 AU to 6 AU, in orange thetion with a gap devoid of gas from
10
10-6
200
17
0
-2 -72
contribution from 1.2 to 2.5 AU,10inblue the contribution from0.06 The detection of ro-vibrationalemissionof the10CO 2850
isotopologs
1
10
1
10
1
10
3150 3450 3750 4050
to 15 AU, and in red the total line-profile;Rb)similar plot but for C18RO[AU]and0 C17 O indicates that Rthe
0.000
[AU]
[AU]
[K]
-4
emitting medium
mustEube
10
1
10
1
10
13
13
13
a gap devoid of gas of width 1 AU extending
from 5 to 6 AU.Flux Density
Gas temperature
COwarm.
R(4)Cumulative
Flux
CO R(4)CO10
dense and
ToRconstrain
theaveragetemperatureand col1
[AU]
800
0.015
100
-68 R [AU]
Error bars on the spectrum are 1 .
[AU]
umn density of the gas 80
probed in the CRIRES spectra, we R
mod18
Line
Flux
DensityC
O R(6)
12
13 optical depth
18
600
-69
eled the CO, CO and C O line fluxes0.015
using a simple semi0.010
60
CO P(9)104 model
infinite slab
in LTE
with a single gas temperatureand col400-70
CO R(4)1740
umn density.
We
did not model the C O observations because
0.005
C O R(6)
200
-71
102
0.010
20
-2

Gas column density [g cm ]24

[K]0.2400R [AU]

1010-30.2400220
10-4Fig. 6. red contour plot of the modeledrotational
diagrams for
10
12131019180.1200CO, CO,and C O using a single
and surface
10-5 temperature
18
2
10
-6
density slab
model. The combined10 red contour plot is obtained
1017
0.0 0
by simultaneously
using
all
the
data
of
the
three
isotopologs. The
1
10
1 1
10 10
2
cross indicates the locationof the red minimum in eachpanel.
R [AU]R [AU]R [AU]

30

0.3600

10-2
10-3
10-4

%s-1 cm-2 µm-1][10-10 erg

-10 0
10 20
Velocity [km s-1]

10-1

10
10-6

10 2

[erg s-1 cm-2 sr-1][K]

NH [cm-2]

NH [cm-2]

Normalized Flux

10

1.0
-20

10
1020

10

3

1020

1016 1023
100 22
200

1.1

-30

600

best-fit 10grid model: ↵NH inner10=+2.0

10 2

4

1.2

22

1020
1018

500

combined
21

1018
1017
1

3

1.3

22

10

_ = -1.8
1.2 to 4.0 AU
5.0 to 15 AU
mergedno gap104001024 CO ro-vibrational
A. Carmona et al.:emission in the transition
disk HD 139614.
-5
1019

1024

gap from 4 to 5 AU

10
300
1023
1022

o

a)

500

[erg s cm-2 sr-1]

30

400

0.48000-10 erg s-1 cm-2 µm-1]

-10 0
10 20
Velocity [km s-1]

300

103

-20

200

Gas teFlux Density0[erg s-1 cm-2 sr-1]
[K]

10

100

-2

Gas column density [g cm ]
24

16

10 3

-30

16

%

1.0

R

-1

10

1019

1018

10

1018

NH [cm-2]

1.1

1021
1020
1018
1017
1

10 2

10

NH [cm-2]

1.2

13

CO p=1-0

10•10 大きなギャップを仮定すると，_ = -1.8
1.2 to 2.5 AU
6.0 to 15 AU
mergedno gap1.3
Normalized Flux

1226

NH [cm-2]

gap from 2.5 to 6 AU

1024
1023
1022

0.0

-40

-20

0

20

0
Velocity [km s-1]
0.000
1
10
13
1 CORR(4)
[AU]
0.4
R [A
0.3
Cumulative Flux C

100
0.2

80

0.1

60

0.0

1

858v1 [astro-ph.SR] 15 Sep 2016

TRANSVERSE VELOCITY SHIFTS IN PROTOSTELLAR JETS: ROTATION OR VELOCITY ASYMMETRIES?
Fabio De Colle 1 , Adriano H. Cerqueira2 , Angels Riera3
Draft version September 19, 2016•!
•arXiv:1609.04858
ABSTRACT
Observations of several protostellar jets show systematic di↵erences in radial velocity transverseto the jet propagation direction, which have been interpreted as evidence of rotation in the jets. In
this paper we discuss the origin of these velocity shifts, and show that they could be originated byrotation in the flow, or by side to side asymmetries in the shock velocity, which could be due toasymmetries in the jet ejection velocity/density or in the ambient medium. For typical poloidal jet
velocities (⇠ 100 200 km s 1 ), an asymmetry & 10% can produce velocity shifts comparable tothose observed. We also present three dimensional numerical simulations of rotating, precessing andasymmetric jets, and show that, even though for a given jet there is a clear degeneracy between thesee↵ects, a statistical analysis of jets with di↵erent inclination angles can help to distinguish between
the alternative origins of transverse velocity shifts. Our analysis indicate that side to side velocities
asymmetries could represent an important contribution to transverse velocity shifts, being the mostimportant contributor for large jet inclination angles (with respect the the plane of the sky), and can
not be neglected when interpreting the observations.
Subject headings: hydrodynamics – shock waves – methods: numerical – stars: formation – ISM:
Herbig-Haro objects – ISM: jets and outflows – ISM: individual (HH 30, DG Tau,CW Tau, RW Aur, Th 28)

ジェットの軸の左右で視線速度に差がある物があり，ジェットの回転と解釈されている．

ジェット軸の左右でジェットの速度に非対称性（~ 10%）があれば，回転はなくても視線速度の差は説明出来る．

!
•

1. INTRODUCTION

timation of the amount of angular momentum extracted
from the star-disk system. This is a key parameter thatcan be used to understand the origin of protostellar jets,
Bacciotti, theF. etgeneralal. (2002)
and might also help to understandmechanism responsible for the production of astrophysical jetsat di↵erent scales.
Recent observations of HH jets show transverse velocity shifts in several emission lines. Davis et al. (2000)
first observed a shift in the H2 lines for the molecular
jet HH 212. Bacciotti et al. (2002) observed the DG Tau
micro-jet, much closer to the central source and in atomic
lines, finding a similar shift in several emission lines.

モデル計算と数値シミュレーションから定量的
Astrophysical jets can be found in a variety of physicalscales, energies and environments. For instance, planeに検証し，左右の視線速度の差を回転とは断定
tary
nebulae, cataclysmic variables, neutron stars and supernovae sometimes show bipolar jets (e.g., Livio 1999).
In
active galactic nuclei, we can see accretion powered
出来ないことを主張．
jets emanating from the central engine (Yuan & Narayan
2014). In star forming regions, jets are ubiquitous andcan be found associated with young stellar objects ranging from brown dwarfs to high mass stars (e.g., Li et al.
2014).
Star forming regions like Orion and Taurus show aジェットの傾き角による輝線の見え方の違い
3

shifts in protostellar jets

Rotationy, v),
, can
t per
lving

1

0.2
0

he in2flow ,
magscopeo(4)

sivity
ocity
< r0
vz is
a despectetriesn theby a/Rj ),
nsity
ults.
tione exh reransed as

Normalized Flux

(3)

=10o

0.8
0.6
0.4

(2)

t ver) by

Asymmetry1-100

傾き角が小さいと回転の効果が重要
で，傾き角が小さいと速度の非対称
性が重要

=45o

0.8
0.6
0.4
0.2
0
1
0.8
0.6
0.4
0.2
0

=80o

0

100

200

0

100
-1

200

Radial velocity [km s ]Fig. 2.— Intensity profiles of synthetic emission lines computed inpositions symmetric with respect to the jet axis (black, full line andred, dashed lines), for a jet with rotation (left panels) and with velocity asymmetries (right), for inclination angles ✓ = 10 , 45 , 80
(upper, middle, lower panels respectively) with respect to the planeof the sky. The radial velocity di↵erences, given by the shifts in thesynthetic emission lines, depend strongly on the jet inclination angle. In particular, rotation (asymmetry) produces a larger velocity
shift for small (large) jet inclination angles.

観測結果と合わせるためには，v ⇠ 5 km s

流体の数値シミュレーションで境界

1

Figure 2 also shows that the TVS produced by rotation and velocity asymmetry strongly depend on the jet
inclination angle. In fact, the velocity gradient between
two fluid elements located at positions symmetric withrespect to the jet axis (i.e. at = 0, y = y0 and y = y0 )is given (see equation 1) by:vz ⇠ 15 km svr = vr (y0 , 0) vr ( y0 , 0) == 2v (r0 ) cos ✓ + vz sin ✓からジェットを噴出させ，そのシミュ
1(5)（ジェットの速度
~
100
km/s）
for a

orrewith

where vz = vz (y0 , 0) vz ( y0 , 0) is the transverse gradient of the jet velocity.
If the jet is nearly axisymmetric, vz ⌧ v . In this

レーション結果から輝線を求め，同様の結論を得ている．