The Star Formation Newsletter#334, 15-21
島 和宏 (京都)2021/01

#15

#16

#17

#18

#19
#20

#21

#15

https://arxiv.org/abs/2009.12549

Motivation:

massive cluster の初期条件が知りたい

How:
OMC-1 region の N2H+ (J=7-6) line emission を観測
Result:The ﬁrst detection

なぜN2H+ か？
低密度n(H2) ~ 102 cm-3

高密度n(H2) > 104 cm-3

原始星誕生or 外部輻射

H+3 + CO ! HCO+ + H2 .

On the other hand, N2 H+ is destroyed +via proton trNH
存在比2CO:
N2 H+ + CO ! HCO+ + N2

低COに阻害される
as well as via dissociative recombination:

N2 H+ + e ! NH + H or N2 + H.
3

http://www.apex-telescope.org/telescope/efficiency

COはダストに吸着
Article number, page 4 of 8

高ダストが溶けてCOが戻ってくる低これまでN2H+ (J=1-0): 93 GHzn(H2) < 106 cm-3

さらに高密度n(H2) ~ 107 cm-3

N2H+ (J=3-2): 279 GHz

high-J transitionsの観測が必要

N2H+ (J=7-6): 652 GHz

Atacama Pathﬁnder EXperiment (APEX)(Credit: ESO)

V. Belitsky et al.: SEPIA – a New Single Pixel Receiver at the APEX Telescope
Table 1. Summary of the SEPIA ALMA Band 5 specifications and performance.

ItemTechnologyRF bandIF band
IF bandwidth
SSB noise temperature
Sideband rejection ratio
Cross-polarization

Characteristics/Specs
2SB SIS mixers, dual polarization
157.36–211.64 GHz
4–8 GHz4 ⇥ 4 GHz
< 50 K> 10 dB< 23 dB

Comment

Swedish-ESO PI Instrument for APEX (SEPIA)
For each sideband

Averaged over RF band < 45 K
Averaged over IF > 16 dB
At the cartridge RF window

Fig. 6. Atmospheric transmission at Llano de Chajnantor (Paine 2017)
for the frequency ranges of the band 5 (upper panel) and band 9 (lowerpanel) receivers.

Fig. 5. Left: Picture of the SEPIA ALMA Band 9 pre-production receiver cartridge. Top right: Typical co-polar beam pattern in a Band 9cartridge (polarization 0 in cartridge #63, picture from Baryshev et al.
(2015), with the secondary telescope mirror indicated (white circle).
Bottom right: Noise temperatures of the SEPIA Band 9 cartridge.

To determine the beam coupling efficiencies for Band 5, weobserved Mars on UT 2016 April 6 and 7 at 208 GHz, and Jupiteron UT 2016 August 11 at 170 GHz. The respective apparent sizesof these planets were 12.700 for Mars and 31.400 for Jupiter. Fromthe same planet observations, we derive deconvolved beam sizesof about 28.600 at 208 GHz and 31.700 at 170 GHz. This means
the apparent size of Jupiter matched the beam size, while Mars
was an unresolved source (semi-extended in the Herschel/HIFIBelitsky et al. (2018)

A&A proofs: manuscript no. O M C1_SEPI A660
target: OMC-1 region @ theOrion Nebula Cluster (ONC)

Fig. 1. New SEPI A660 observations along the O M C-1 region. From left to right: (a) V ISTA-IR K s band (Meingast et al. 2016), (b) APE XMeingastal.X-SEPI(2016)(thiswork)
SEPI A660 N 2 H + (7–6),
and (c)etAPE
A660 C 18 O (6–5) maps (this work). A ll molecularmaps
are convolved into a common Nyquist
grid with a final resolution of 10". The intensity the H41↵ emission tracing the extension of the O N C HII nebula (red contours, Hacar et al.
2020) is indicated in the V ISTA image. Panels b and c display equally spaced contours (black) every W(N 2 H + (7 6)) = 2.5 K km s 1 and#20

https://arxiv.org/abs/2009.08857

Motivation:

星形成の初期条件が知りたいHow:
H2D+ 110-111 と N2H+ 4-3 でgas dynamicsを推定
Result:the Larson-Penston ﬂow モデルとよく一致opacity at 1.3 mm κ1.3 mm=0.009 cm2 g−1 (corresponding todust grains with thick icy mantles and 106 yr of coagulation;
Ossenkopf & Henning 1994), consistent with recent ﬁndings(Chacon-Tanarro et al. 2019), the kernel mass can be found using
D 2S1.3 mm

H2D+ 110-111

N2H+ 4-3A&A proofs: manuscript

Article number, page 5 of 32of H2 D+ line emission as observed with JCMT towards the cores L1521f, L183,
L1517B,
L694-2,and L1544.
+Fig.
2. Spatial
distributionof The
N2 Hred4-3 as observed with JCMT towa
the 850 µm emission. The area filled with light green indicates the clear (>3 ) detections and the possible detections
emission detections. The area filled with light green indicates the cle
ape and peak velocity position.

shape and peak velocity position.

Fig. 5. As Fig. 3, but for L1517B.

FialcoanArticle number, page 5 of 32

stribution of H2 D+ line emission as observed with JCMT towards the cores L1521f, L183, L1517B, L694-2, and L1544. The rede peak of the 850 µm emission. The area filled with light green indicates the clear (>3 ) detections and the possible detections
the line shape and peak velocity position.

thermal成分より大きな線幅 -> gas dynamicsが見えてるTatim
coemission observations in the optically thin regime that can trace
those kinematics are therefore crucial. The models of interest aredescribedpre-stellar
below.
coreのproﬁleを仮定

LPモデル

SISモデル1.08LPSIS

QE-BES0.5

7

実線:
rom the literature
agani 密度proﬁleet al. 2007;

6log velocity (km/s)

0.0

log density (cm 3)d velocity structure
ture. The dynamied in Sect. 5.2. For
ure is equal to thents of high volume
f 100.
0⇥20 observations,ed shells for eachu for all cores exu due to its larger
city structures are
Keto et al. (2015)
in more detail in

0.5
5

1.0
1.5

点線:
速度proﬁleemission using RATRAN.

––—

4
cón-Tanarro et al.
e derived using ra2.0
as (e.g., N2 H+ ) or32.5), and are specificdefinition isother2
3.0
e of temperatures,
123
45
6perature variations
log radius (au)emperature profile
htness of the line,. In this study, we Fig. 8. The density (solid line) and velocity (dashed line) profiles ofy dependent on the ->a prestellar
core predicted by the three dynamical models: LP flowline emissionを再現できるかRATRANで計算
s of the gas, rather (green), SIS (red), and QE-BES (blue), as presented in Keto et al.
(theCarloradiativetransfercode)of the Montemodelled profiles
was adopted
to model theH2 D+emperature; there- (2015). Each

cript no. prestellar_cores_acceptedA&A proofs: manuscript no. prestellar_cores_accepted#16

https://arxiv.org/abs/2010.06825

Motivation:連星系の形成シナリオが知りたいHow:young proto-binary systemの回転軸を観測
Result:misaligned = disk fragmentationでは説明できない

連星系の形成シナリオ (classical modal)
disk fragmentation

turbulent fragmentation

回転軸はそろってる

回転軸はそろわないVLA 1623 (Class 0 object)

Hara et al.

70°

e 1. The continuumALMA
maps1.3m
of VLA
1623. The contours
in7.3
(a)mm
andcontinuum(b) show the 7.3 mm concontinuum
JVLAon obtained with The Karl G. Jansky Very Large Array (JVLA) observations in (Kawabe et al.

twin outflow from vla 1623

33

twin outflow from vla 1623

Figure 15. The front view including each disk of the protostellar binary and its binary orbit
the CB disk.

separation ~ 36 au

12high-velocity
ALMA
CO(2-1) 12 CO maps. The blue and red colors
Overlay of the low-velocity 12 CO(2–1)
on theperiod ~ 460 yrb) represent blueshifted and redshifted intensities integrated between VLSR =-34.5 to -10.5 km

misaligned by 70°5 to 31.5 km s 1 . The cyan and magenta contours superposed on 2-color image in (a) and (b)emission integrated over intervals from VLSR =-10.5 to -0.5 km s 1 , and from 6.5 to 14.5 km
1twin outflow from vla 1623

3342

twin outflow from vla 1623

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eenewannohoii(12high-velocitya12) CO
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in red colors
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dbOverlay of the low-velocity 12 CO(2–1)
on themaps.
andfih)csoa(tm.
aeT(stsandeirnnlnge
1 annsitioiag ~ 460 yre b periodaiaedhsynt
Moispe c =-34.5-Vb) represent blueshifted and redshifted intensities integrated
VTLSRl. to -10.5
d l between
ws kmhekPeoadhhepeas).
th)smoafDdb(misalignedby 70°t(eoejmn (a) andn (b)urilos5 to 31.5 km s 1 . The cyan and magenta contours superposed
on2-color
imageinoairaebitdflinn ct
mereutodfa
rearcul km ws th1e, andhefromelnaemission integrated over intervals from VLSR =-10.5 to -0.5
6.5
to 14.5 km
cli
Tt.
hosfinestioestab1ulinne#17

https://arxiv.org/abs/2009.05052

8CMZ OOM TEAMCMZにあるcompact sourceのカタログ285個 > 6σFigure 4. The average mass of compact sources per unit area surveyed from the robust catalog as a function of Galactic longitude (top) andlatitude (right) with leaf contours (in red) and the surveyed area footprint (blue) over the Herschel N(H2 ) map from Battersby et al (in prep)(bottom). Clouds/regions are also labeled by their colloquial names. We detect high concentrations of mass in compact sources per area
surveyed in Sgr B2, Sgr C, the Dust Ridge, the 20 and 50 km s-1 clouds, the Brick, and the three little pigs, while other regions of high column
density lacking a similar degree of compact substructure. This is quantified in Paper I (Section 5.4) as a compact dense gas fraction, calculated
as both SMA flux divided by Bolocam Galactic Plane Survey flux or SMA mass divided by Herschel mass. For an in-depth look at the compact
dense gas fraction of these clouds, we refer the reader to Paper I.

816個 > 4σ

4.3. Physical properties

weight µH2 = 2.8 (e.g. Kauffmann et al. 2008), and mH is the#18

https://arxiv.org/abs/2009.07837

pebble が protoplanet に突っ込んだらどうなるか？

https://arxiv.org/abs/2009.11868

V. M. Kalari et al.
64

30

LMC65
Declination(J2000)

2

#1966

Magellanic Bridge

SMC67
68
69
70
71

6h

5h

4h
3h
RightAscension(J2000)

2h1h

あんまり違いはない？

Figure 1. The position of MB-C in the sky from an archive Digital Sky Survey image, along with the position of the Large and SmallMagellanic Clouds labelled and seen as overdensities in the optical image. Overlaid are H i contours from the Parkes All Sky Survey(Meyer et al. 2004) at levels of 1, 10, 25, 50 and 100 counts. MB-C is marked by the solid circle, showing its relative isolation from the#21

https://arxiv.org/abs/2007.09160

Orion Complexの形成シナリオについて

7