We investigate high resolution imaging polarimetry of HD 169142 taken in the R' and I' bands with the SPHERE/ZIMPOL instrument for an accurate quantitative measurement of the radiation scattered by the circumstellar disk. We observe a strong dependence of the disk polarimetry on the atmospheric turbulences, which strongly impact the AO performance. With our non-coronagraphic data we can analyze the polarimetric signal of the disk simultaneously with the strongly variable stellar PSF, correct for the convolution effects to determine the intrinsic polarization of the disk with high precision. We also extract the disk intensity signal and derive the fractional polarization. We compare the scattered flux from the inner and outer disk rings with the corresponding thermal dust emissions measured in the IR and estimate the ratio between scattered and absorbed radiation. We obtain ratios between the integrated disk polarization flux and total system flux of 0.43% for the R' band and 0.55% for the I' band. This indicates a reddish color for the light reflection by the dust. The inner disk ring contributes about 75% to the total disk flux. The obtained fractional polarization for the bright inner disk ring is 23.6% for the I' band and similar for the R' band. The ratio between scattered disk flux and star flux is about 2.3%. This is much smaller than the derived IR excess of 17.6% for the disk components observed in scattered light. This indicates that only a small fraction of the radiation illuminating the disk is scattered; most is absorbed and reemitted in the IR. We conclude that accurate, quantitative measurements of the scattered light from circumstellar disks are possible with ground based high contrast AO systems, if the PSF convolution effects are properly taken into account, and this provides important new constraints on the properties of the scattering dust.
One Hundred Years of Venus Polarimetry: PICSARR Observations of the Phase Curves
University of New South Wales（新南威尔士大学）；Monterey Institute for Research in Astronomy（蒙特雷天体物理研究所）；SETI Institute（搜寻地外文明研究所）；California State University, Long Beach（加州州立大学长滩分校）
Imaging the LkCa 15 system in polarimetry and total intensity without self-subtraction artefacts
European Southern Observatory（欧洲南方天文台）；Indian Institute of Astrophysics（印度天体物理研究所）；Pondicherry University（本地治里大学）；University of Potsdam（波茨坦大学）；University of Galway（高威大学）；The University of Tokyo（东京大学）
Near-Infrared Imaging Polarimetry of Inner Region of GG Tau A Disk
通过使用Subaru/HiCIAO进行无掩模偏振成像，在$H$波段成功探测到GG Tau A系统周围盘内部区域的偏振散射光，空间分辨率约为0.07 $\arcsec$，揭示了这颗年轻双星周围复杂的内部盘结构。本文报告了在GG Tau Ab以北观测到的弧形结构和在GG Tau Aa周围延伸到距离主星约28 AU的拱星结构的一部分。GG Tau Ab周围的斑点噪声将其盘半径限制为<13 AU。根据环联星环的大小和围绕着GG Tau Aa的星周盘，联星轨道的半长轴可能是62天文单位。目前的观测结果与以前的ALMA和近红外（NIR）H $_2$发射观测结果的比较表明，北弧可能是一个大的流光的一部分，从环联星环流动，以维持拱星盘。根据先前的研究，GG Tau Aa周围的拱星盘有足够的质量，可以维持足够的时间来行星形成;因此，我们的研究表明，行星可以在近距离（距离$\lesssim$ 100 AU）的年轻双星系统中形成。
High-contrast Polarimetry Observation of T Tau Circumstellar Environment
我们使用安装在斯巴鲁望远镜上的HiCIAO仪器在H波段对T Tau进行了高对比度偏振观测，揭示了接近0. $\arcsec$ 1来自恒星T Tau N和T Tau S。发现整个T Tau系统被星云状的包层所包围，在这些包层中检测到几个与流出有关的结构。我们分析了这个三重年轻恒星系统的每个组件附近的拱星结构的详细偏振模式，并确定对拱星盘和外流结构的约束。我们认为T Tau N星周盘的近正面不大于0。$\arcsec$ 8，或117 AU，在西北部，基于在这个方向上存在一个洞，并且不大于0。$\arcsec$ 27，或40非洲联盟，在南部。新结构“N5”延伸到约0. $\arcsec$ 42，或59天文单位，在恒星的西南方，被认为是圆盘的一部分。我们认为T Tau S被一个半径约为0. $\arcsec$ 3，或44天文单位，位置角约为30 $^\circ$，与T Tau S双星的轨道不一致。在分析了流出相关结构的位置和偏振矢量模式后，我们认为T Tau S应该触发众所周知的东西流出，也可能是西南旋进流出“线圈”和可能的南流出的原因。
Detecting alien living worlds and photosynthetic life using imaging polarimetry with the HWO coronagraph
IRSOL, Universitá Svizzera italiana（瑞士意大利大学）；University of Bern（伯尔尼大学）；SETI Institute（SETI研究所）；NASA（美国国家航空航天局）；ESO（欧洲南方天文台）；University of Central Florida（中佛罗里达大学）；Leiden Observatory, Leiden University（莱顿大学）；Technical University Delft（代尔夫特理工大学）
