The First Census of Accreting Proto-Planets inside the Gaps of Transitional Dust Disks

目前已知有数千颗富含气体的系外行星。这些都不是真正的原行星，它们在形成时迅速吸收周围区域的气体。研究人员已经开发出一种方法来探测正在形成的行星中氢气的添加。这种方法可以用于搜索位于恒星周围的尘埃盘中的空白区域或间隙，这些区域预计会形成行星。这个团队有一个独特的仪器系统，他们设计并测试了这个系统，现在正在智利的一个6.5米望远镜上使用。他们首次探测到氢气被吸入一颗形成中的行星，这颗行星的大小是木星的两倍，位于尘埃盘的间隙中。这个项目的核心是应用他们的技术在25个附近的、年轻的、有已知间隙的圆盘中寻找原行星。他们计划了解气态巨行星是如何形成、成长并影响其形成的尘埃盘的。这个项目增加了我们对行星形成方式的了解，符合国家利益。研究人员将在这个研究项目中培训本科生、研究生和博士后科学家。首席研究员将在图森地区的小学和中学以及图森地区的10个退休社区发表关于原行星调查结果的公开演讲。虽然现在已知有数千颗富含气体的系外行星，但没有一颗是真正的原行星，它们是快速吸积气体的。智利6.5米麦哲伦望远镜上的MagAO系统是唯一一个在最强可见气体吸积发射线（H-alpha）上发布0.03弧秒分辨率图像的自适应光学系统。过渡盘是指有防尘间隙的磁盘。一个流行的假设是，这些间隙可以被间隙中的多个（2-3）大质量吸积行星清除。该团队首次明确探测到一颗质量约为木星两倍的原行星，位于LkCa 15过渡盘间隙的h - α。该团队将利用他们在原行星直接成像方面学到的所有经验，扩大他们的观测研究，对附近的原行星进行首次普查。他们期望了解低质量气态巨行星在哪里形成、生长，以及它们如何影响宿主盘/间隙。该团队将利用MagAO的独特能力，同时拍摄h - α（波长= 656nm），连续体（642nm）和Ks （2147nm）图像，使用新的同步差分成像光学系统（名为GAPplanetS+）对原行星进行调查。他们将调查所有25个最近的（~ 150pc），最年轻的（~ 1myr），最亮的（R12等）大间隙（130mas）过渡盘，以进行第一次原行星普查。研究人员将在这个研究项目中培训本科生、研究生和博士后科学家。首席研究员将在图森地区的小学和中学以及图森地区的10个退休社区对GAPplanetS+调查结果进行公开讲座。

Thousands of gas-rich exoplanets are now known. None of these are true protoplanets that are rapidly adding gas from the areas surrounding them as they form. The investigators have developed a method of detecting the addition of hydrogen gas into a forming planet. This method can be used to search the empty regions or gaps in dust disks located around stars where planets are expected to be forming. The team has a unique instrumental system that they designed, tested, and now use with a 6.5-m telescope in Chile. They have made the first detection of hydrogen gas being drawn into a forming planet about twice the size of Jupiter in the gap of a dust disk. This project centers on applying their technique to search for protoplanets in 25 disks that are nearby, young, and have known gaps. They plan to learn how gas giant planets form, grow, and affect the dust disks in which they are forming. This project serves the national interest by increasing our understanding of how planets form. The investigators will train and include undergraduate and graduate students, and post-doctoral scientists, in this research project. The principal investigator will give public lectures on results from the protoplanet survey at Tucson area elementary and middle schools, as well as 10 Tucson area retirement communities.While thousands of gas-rich exoplanets are now known, none are true protoplanets that are rapidly accreting gas. The principal investigator's MagAO system on the 6.5-m Magellan Telescope in Chile is the only adaptive optics system that has published 0.03 arcsec resolution images at the strongest visible gas accretion emission line (H-alpha). Transitional disks are disks that have dust-poor gaps. One popular hypothesis is that these gaps could be cleared by multiple (2-3) massive accreting planets in the gap. This team has made the first definite detection of an approximately 2x Jupiter mass accreting protoplanet at H-alpha in the gap of the LkCa 15 transitional disk. The team will expand their observational studies by leveraging all the lessons they have learned about direct imaging of protoplanets to make the first census of nearby accreting protoplanets. They anticipate understanding where low mass gas giant planets form, grow, and how they affect their host disks/gaps. The team will utilize MagAO's unique ability to take simultaneous H-alpha (wavelength = 656nm), continuum (642nm), and Ks (2147nm) images to carry out a survey for protoplanets with the new simultaneous differential imaging optics, named the GAPplanetS+. They will survey all 25 nearest (~150 pc), youngest (~1 Myr), brightest (R12 mag) large gap (130mas) transitional disks for the first census of protoplanets. The investigators will train and include undergraduate and graduate students, and post-doctoral scientists, in this research project. The principal investigator will give public lectures on results from the GAPplanetS+ survey at Tucson area elementary and middle schools, as well as 10 Tucson area retirement communities.