Imaging the disk around IRAS20126+4104 at subarcsecond resolution
R. Cesaroni1, D. Galli, R. Neri and C.M. Walmsleycesa_24.pdf
The existence of disks around high-mass stars?
大質量星形成は、ディスクを通じた降着という中小質量星形成の道筋のスケールアップ
か？
理論的には大質量原始星の周りに円盤があるべき。B 型星に少数見つかっているのみ。
IRAS 20126+4104
the IRAM six-element array at Plateau de Bure

高励起、うすい遷移

v8=1 CH3CN(12 11) transitions, CH313CN isotopomer
NE
速度差小SW
速度差大低励起先行研究
Cesaroni et al. 2005 CS 観測

7Msol, ~0.03pc 円盤

Keto&Zhang (2010), CH3CN and NH3 マップなし M> 8.3 Msol M~10.7Msol
CS より高密度トレーサ
PV 実線 M=7Msol 破線 M=10Msol のケプラー回転円盤内非軸対称構造

遷移ことの強度ピークの速度と位置の関係

ジェットと円盤の共回転性

水メーザ

Study of background star polarization and polarization efficiency of three selected Bokglobules CB56, CB60 and CB69
A. Chakraborty, H.S. Das, and D. Paul1405.6269.pdf
偏光度-減光関係
pv/Av ∝ AVα, where α = −0.56 ± 0.36 (CB56),−0.59±0.51 (CB60) and −0.52±0.49 (CB69).
考えられる理由 poor grain alignment, grain growth, and or changes in grain shape orcomposition (Gerakines et al. (1995))
Whittet et al 2008 interstellar polarization efficiency の変化αで整列のモデルが決められる？
V バンドで Bok グロビュールの偏光効率の測定を行った。

Near Infrared Spectroscopy of Young Brown Dwarfs in Upper Scorpius
P. Dawson, A. Scholz, T.P. Ray, D.E. Peterson, D. Rodgers-Lee, V. Geers
1405.3842.pdf
forming brown dwarfs: (Whitworth et al. 2007)(1) turbulent fragmentation of molecular clouds, producing very-low-mass prestellar
cores by shock compression; 乱流分裂による極小の星なしコア形成による(2) collapse and fragmentation of more massive prestellar cores; 普通の星なしコアの収縮中の分裂(3) disk fragmentation; ディスク分裂(4) premature ejection of protostellar embryos from their natal cores; 初期原始星の動的放出(5) photoerosion of pre-existing cores overrun by Hii regions HII 領域による原始星コアの蒸発
UpSco 多くの褐色矮星を含む(Preibisch et al. 2002), 距離 145±2 pc、重元素～太陽組成、固有運動測定

Class II

H-peak
H2OClass III

IRTF＋SpeX spectrograph 0.8 - 2.5 μm.
H-Peak Index: the ratio of the fluxes measured in the intervals between 1.675-1.685 μm and 1.495-1.505 μm
SpT = −0.84 + 7.66 × HPI
H2O index: the ratio of the fluxes in the intervals between 1.550-1.560 μm and 1.492-1.502 μm
H2O = 0.75 + 0.044 × SpT(どちらも H2O absorption band at 1.3-1.5 μm and the peak in flux at 1.68 μm)
Sp 型

24 個について M5 ～L1,Class II （WISE 衛星の観測より 5，11，12）

The VLT/NaCo Large program to probe the occurrence of exoplanets and brown dwarfs
in wide orbits: I- Sample definition and characterization S. Desidera et al.
1405.1559.pdf
NaCo Nasmyth Adaptive Optics System (NAOS) Near-Infrared Imager andSpectrograph (CONICA)で search for planets and brown dwarfs in wide orbits around86 stars を行った。
To improve target age determination のために FEROS and CORALIE spectrographs at
La Silla Observatory で高分散分光を行った。
結果(1)The median distance and age of our program stars are 64 pc and 100 Myr,
respectively.
(2)Nearly all the stars have masses between 0.70 and 1.50 M⊙, with a median value of1.01 M⊙.
(3)The typical metallicity is close to solar, with a dispersion that is smaller than that ofsamples usually observed in radial velocity surveys.
(4)Several stars are confirmed or proposed here to be members of nearby young moving
groups. Eight spectroscopic binaries are identified.

isochrones for 5, 12, 30,70, and 200 Myr

The VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs
at wide orbits: II- Survey description, results and performances by G. Chauvin et al.
1405.1560.pdf
the statistical analysis of the occurence and orbital distributions of giant planets andbrown dwarf companions at wide (> 5 − 6 AU) orbits.
NaCo at VLT to explore the occurrence rate of giant planets and brown dwarfs between
typically 0.1 and 8”.

性能 primary star-companion brightness ratios as small as 10−6 at

1.5”
76 stars were observed

結果(a) one companion candidate or more were detected for 43 targets(b) For the 29 systems with at least 2-epochs observations (including the Moth system),With the exception of HD8049 B, we did not identify any new comoving companions.
(c) Considering the survey detection limits, a preliminary upper limit on the frequencyof giant planets for semi-major axes of [10,2000] AU:(1) typically less than 15% between 100 and 500 AU (for M>5 MJup),(2) and less than 10% between 50 and 500 AU (for M>10 MJup)
considering a uniform input distribution and with a confidence level of 95%.