THE	  STAR	  FORMATION	  NEWS	  LETTER:	  No.	  244	  7	  April	  2013	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  	  担当 麻生	  (東大)	  	  	  	  	  	  2013/4/26	
Forma&on	  and	  evolu&on	  of	  interstellar	  ﬁlaments;	  Hints	  from	  velocity	  dispersion	  mea-­‐	  surements	  	  D.	  Arzoumanian,	  Ph.	  Andre,	  N.	  Pere3o,	  and	  V.	  Konyves	  	  D. Arzoumanian et al.: Formatiol Aquila,	  Polaris星間雲の速度分散を調べた。	  
l T=10	  K,	  幅0.1	  pcでは熱的臨界線密度Mline,crit=2cs2/Gは、中心柱密度8e+21	  cm–2	  (Av~8)に相当。	  (cf.	  星形成threshold	  Av=6~9)	  l IRAM	  30	  mでC18O	  2–1,	  13CO	  2–1,	  N2H+	  1–0	  	  	  	  	  	  	  à乱流を求めて水素の音速と合わせた。	  
l NH2<8e+21	  subcriZcal	  à	  cs<σtot<2cs	  (NH2に依らない)	  ,	  unbound	  乱流でフィラメントが支えられている。	  
l NH2>8e+21	  super	  criZcal	  l à	  σtot∝NH2,obs0.35	  ,	  bound	  重力収縮、Σ0が多くなるとσtotも大きくなり~0.1	  pcを維持。	  
l Σ0はevoluZonary	  indicatorになる。	

0.3and0.1
0.05
3.4.RDensity
velocity
Pl (pc)
Qi

0.3

0.4

0.5

all models, the syste
Reverse	  dynamical	  evolu&on	  of	  Eta	  Chamaeleon&s	  For	  Plummer
model

Christophe	  Becker,	  Estelle	  Moraux,	  Gaspard	  Duchene,	  Thomas	  ! distribut
3.4. Density andvelocity
3NsysρPl (r) =1 + (r/R
Maschberger	  and	  Warrick	  Lawson	  3 systems arePl
For all models,the4πR
Plummer model

Pll η	  ChameleonZs、6-­‐9	  Myr,	  d=94	  pc,	  18	  systems	  in	  r=0.5	  pc	   where Nsys! is the initial" nu3Nsys
2 −5/2ρPl (r) =The 3velocities
1 + (r/RPl )of eacl m<0.1	  Mo,	  rbinary>50	  AUが少ない。	  
4πRPlseparaZon	  30	  AU以下は18%	  (cf.	  TW	  Hydrae	  assoc.	  58%)	   cording to this density dis
wherenumber/Einitial
Eof
Qi N=sysEiskinthe
pot wherekinl universal	  IMFから力学進化だけで再現できるか？	  
Thevelocitiesofeachindividter and Epot the gravitati
thiswithdensity
distributionl モデルパラメーター(初期状態)はNsys,	  RPl,	  Qで指定。	   cording
thustoleft
threefree p
A&A 552, A46 (2013)

Number of systemsl 成功率の分布を見ると最適解がありそうだが、同時刻ではないのでダメ。	  
l binary選び方、brown	  drarfの分布を変えてもダメ。	  
l 初めからm<0.1	  Mo,	  rbinary>50	  AUを少なくすると成功。	  
l 結論)	  力学進化は重要ではない	  

	0.3
0.1
0.05
0.03
0.01
0.005

Ekin is the to
Q = Ekin /E
potofwhere
Halostars
tems
N,
thePlummer
rasys
ter and Epot the gravitational 1.00
ener
thus left with three free parametertems Nsys , the Plummer radius RPli
Number of massive stars

3.5. Parameter grid

3.5.FromParameter
grid
the shapeof the IM

N= 50 by the requirem

Fromsys
the shape of the IMF, 0.10
we70 20 3040 "50. To60 70
1M
coveraw
N 20 30 40 50 60 70 20 30 40 50 60 thanNsys = 50 by the requirement to hav
Number of VLMOs
Binary fraction weNumberof widebinaries
testedNsys
fromtothan 1 M
a wide20range" . To cover
0.3
to fitwe estimatedtested Nsys from20 atoconstan
70. The0.1
estimatedto of
fit astar
constant
surfacevations
forming
re0.05
vations
ofstarforming
regions(A
to 1.0 pc for 50 systems.
0.03
to 1.0 pc for 50 systems. The0.01
stushowedthatadense
initia0.01
showed that a dense initial configu
to ejectenoughmembers
0.005
to ejectenoughmembers
from thRof VLMOs.
Todynfa
the thelacklackof VLMOs.
To favour
N 20 30 40 50 60 70 20 30 40 50 60 70 20 30 40 50 60 70
RPhysical	  proper&es	  of	  ou>lows:	  Comparing	  CO-­‐	  and	  H2O-­‐based	  parameters	  in	  Class	  0	  sources	  	  P.	  Bjerkeli,	  R.	  Liseau,	  B.	  Nisini,	  M.	  Tafalla,	  P.	  Bergman,	  G.	  Melnick	  and	  G.	  Rydbeck	  l アウトフローのejecZon	  mechanismはCO以外で調べても同じなのか？	  
l Herchel、H20(110–101)	  557	  GHz,	  H20	  212–101	  1670	  GHz	  l Class0天体、L1448,	  L1157,	  VLA	  1623	  l COはcold	  entrained	  ambient	  gas	  l H2,	  H2Oはshocked	  gas	  (H2OはCOよりH2をtraceできる)	  l td=Llob/vmax	  (mom1速度だとtdを過大評価、vmaxは過去のCOに一致)	  P. Bjerkeli et al.: Physical properties of outflows from Class 0 sourcesl oullow	  age	  ~103	  yr	  (衝撃波散逸より長く、freeze-­‐outより短い)	  L1157

200150Dec offset (")

100500−50−100−150
100

500−50RA offset (")−100

X-­‐Ray	  Determina&on	  of	  the	  Variable	  Rate	  of	  Mass	  Accre&on	  onto	  TW	  Hydrae	  	  N.	  S.	  Brickhouse,	  S.	  R.	  Cranmer,	  A.	  K.	  Dupree,	  H.	  M.	  Guenther,	  G.	  J.	  
M.	  Luna	  and	  S.	  J.	  Wolk	  The Astrophysical Journal Letters, 760:L21 (5pp), 2012 December 1

1.2

G-Ratio [(f+i)/r]l TW	  HyaからのNe	  IX吸収線を観測し、星への11.1
accreZon	  rateを直接調べる。	  
2l 3つの時刻のデータ	  1.0l Mg	  XI,	  Ne	  X,	  Ne	  IX,	  O	  VIII,	  Fe	  XVII	  (cooling	  column	  0.9of	  the	  shock)	  3l Mg	  XII,	  Si	  XIII,	  Si	  XIV	  (stellar	  corona)	  0.81.5x102.0x102.5x103.0x103.5x10l O	  VII	  (post	  shock)	  T (K)
1.2
6.4l à 時刻3でTeが高く、N6.3
Hが小さい。	  neは一定。	  
6.28
13l NHの変化はaccreZon	  preshock	  streamがX線を吸1.17
収していることを支持。	   211.0l Teは距離(truncated	  radius)のみで変わり、Mdot,	   62B*で決まる。	   0.96.636.55l モデルでMdot,	  B*,	  f	  (hot	  spot	  ﬁlling	  factor)を振っ
0.8
1x10
2x10
3x10
4x10て、Te,	  ne,	  NHを合わせた	  N (cm )
1.5x102.0x102.5x103.0x103.5x104.0x10T (K)l 時刻3ではB*は変わらず、Mdotとfが小さくなった。	  
l X線を使うとMdotは過小評価されがちだが、可視光の結果を合った。	  
666

The Astrophysical Journal Letters, 760:L21 (5pp), 2012 December 1

664.0x106

Brickhouse et al.

eHe α/He β

G-Ratio [(f+i)/r]

Figure 1. Theoretical G-ratio (i.e., ratio of forbidden plus intercombination t
resonance line fluxes) for Ne ix as a function of Te (solid curve) from AtomDB(Foster et al. 2012; Chen et al. 2006). Overplotted are the observed ratios wit
1σ errors (vertical error bars) for the individual observations (open circles
numbered in time order) and for the summed spectrum (solid circle). Horizonta
error bars (dashed lines) show how the errors on the observed ratios translate tthe errors on Te .

Ion

Table 1Emission Line Fluxes

λref a(Å)

Flux (Uncorrected for Absorption)(10−6 photons cm−2 s−1 )Pointing 1b666666e

Figure 1. Theoretical G-ratio (i.e., ratio of forbidden plus intercombination toresonance line fluxes) for Ne ix as a function of Te (solid curve) from AtomDB(Foster et al. 2012; Chen et al. 2006). Overplotted are the observed ratios with
1σ errors (vertical error bars) for the individual observations (open circles,numbered in time order) and for the summed spectrum (solid circle). Horizontal
error bars (dashed lines) show how the errors on the observed ratios translate tothe errors on Te .

Pointing 2b

Pointing 3b

Mg xi
9.17 212.5 ±210.4
1.7
2.4 ± 0.
21 ± 0.5
21Ne x9.71
1.8 ± 0.8 -2
3.1 ± 0.5
2.8 ± 0.
HNe x
10.24
7.0 ± 0.7
9.0 ± 2.0
8.7 ± 0.
Ne ix 2. Ratio of11.00
7.3 ± 0.7 line (Heα)6.6± 1.0
7.9 ± 1.
Figurethe flux of the resonanceto thatof Heβ as a functionofNehydrogencolumn
for given
6.21.
ix
11.54density (dashed19.9 ± curves)
1.5
23.7 ±log
1.8[Te ] (K) from
24.2 ±toNe
6.6xas labeled.12.13
Absorption models
McCammon(1983)
63.8 ±are
3.1from Morrison
74.1 ±&3.3
77.2
± 3.
and
are from Fosteral. (2012). Overplotted
Felinexviiemissivities
12.27
3.2 ±et0.8
4.7 ± 1.0 are the observed
2.1 ± 0.
ratioserror ±bars)
observations(openNe ixwith 1σ errors
13.45(vertical128.3
6.9for the individual
144.7 ± 7.0
187.8
± 8.
circles, numbered in time order) and for the summed spectrum (solid circle).
Ne ix
13.55
93.5 ± 5.5
97.8 ± 5.9
115.4 ± 6.
Observed points are placed on the curve appropriate for their Te as determined
Ne ix
13.70Horizontal47.4± bars4.0 (dotted50.4± show
3.4 how the53.9
± 4.
from
their G-ratios.
errorlines)
errorsWe have preferred to analyse the observed spectrum as it is, andhave tried to obtain information also from the secondary spectrum.
This was not trivial, mostly because no usual spectroscopic methods for the parameter determinations can be applied to the closecompanion. In fact, neither hydrogen lines nor elements with lines
in two different ionization stages are independently observable. Webased our parameters for the secondary mostly on the Ca I line at
6122.21 Å which is a good luminosity indicator (Cayrel et al. 1996).
The two components for this line are rather well separated and freeof blends. Unfortunately, the other two lines of the Ca I triplet at6102.73 Å and 6161.30 Å are blended.
The composite synthetic spectrum normalized to the continuum (PS) was computed according to the relation (Lyubimkov &Samedov 1987)

The	  Herbig	  Ae	  SB2	  System	  HD	  104237	  	  C.R.	  Cowley,	  F.	  Castelli,	  and	  S.	  Hubrig	  λλλc

λc

2
P2P2S2S

λλc

Figure 3. Observed (black) and calculated Ca I λ6122.21, with log (g) =3.7 (light grey), and log (g) = 4.0 (dark grey). The main feature is due to theprimary. Absorption from the same line in the secondary star (see the text)
is to the violet.

SP

Table 2. Adopted parameters for primary and secondary atmospheres.

eff−1−1

Primary
Secondary−1tefft−1I

composite profiles computed for Teff = 8250 K and log (g) = 4.2
for the primary and for both Teff = 4800 K, and log (g) = 3.7 andTeff = 4500 K and log (g) = 4.0 for the secondary. In the first case,the ratio of radii is RS /RP = 1, in the second case it was deduced
from the relation
MS gP
RS2=·.
MP gS
RP2(2)

for a mass ratio MP /MS = 1.29 (Böhm et al. 2004). The too broadwing of the secondary star profile computed for log(g) = 4.0 isevident.
The adopted parameters for the two components (Table 2) were
well suited to reproduce several primary–secondary pairs of profiles
as Fe I at 4950.11, 4969.92, 5002.793, 5393.17, 5576.09, 6065.48,6252.56, 6335.33 Å, Ca I 6717.68 Å, and several others.

Teff Klog (g)ξ turb8250 ± 200
4800 ± 200

4.2 ± 0.25
3.5− ≤ 3.7

2.5 ± 11.0 ± 1

Downloaded from http://mnras.oxfordjournals.org/ at National Astronomical Observatory of Japan on April 18, 2013l 分光連星Herbig	  Ae	  HD	  104237	  (DX	  Cha)	  l weak	  absorpZon	  lineからabundanceを測った。	  
l モデル大気	  (ATLAS9)から主星はTeﬀ=8250	  K,	  重力加速度log	  g=4.2	  F (P )R + F (S)RF (P S)=.
(1)
F (P S)
F (P )R + F (S)Rl 観測された等価幅(連星同士が混ざる)とモデルからの真の等価幅を使うとWe use the subscript ‘λc’ to indicate the continuum at a wavelength
λ. F for the primary (P) and secondary (S) have units of energy per星の半径比がわかる。	  
unit area per sec per Ångström. R are the stellar radii.
After some experimentation with alternate models and differentl 等価幅からabundanceもわかる。	  
radii ratios, we selected a ratio R /R = 1 (see Section 4.4), andthe parameters T = 4800 K and log (g) = 3.7 for the secondary.
was deduced from theA rotational velocity v sin (i) = 12 kml 25元素調べて、ほとんどsolar	  vsalue	  comparison of the observed and computed profiles. We thank thereferee, Barry Smalley, who pointed out that the same v sin (i) andl Zrが最もenhanced、Liもenhanced	  macroturbulence (8 and 9 km s , respectively) would have nearly
the same combined profile as a v sin (i) of 12 and no macroturbul Liは他のHerbig	  Aeでは見つかっていない。	  
lence. This would be the case if the stars were tidally locked.
A microturbulent velocity ξ = 1.0 km s and solar abundancesl Herbig	  AeはmagneZc	  p/CP	  starになると考えられているが、化学的には
K, log (g) = 4.0 and assumed
were assumed. FBA
used
T = 4500
solar abundances and a microturbulent velocity ξ = 2 km s .
indicaZveではない。(solarまたはmild	  oo)	  withtheFig. 3 compares the observed Ca profile at 6122.21λÅ	  B