ALMA Imaging of Circumstellar Disks: Where and When do Planets Form?

星周盘的 ALMA 成像：行星形成的地点和时间？

• 批准号: 1907486
• 负责人: Jonathan Williams
• 金额: $ 35.53万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1907486&HistoricalAwards=false
• 关键词: ALMA; Imaging; Circumstellar; Disks; Where

Both stars and planets form out of clouds of gas and dust. Astronomers have recently discovered that a majority of, if not most, stars have planets, but many of these planetary systems look very different than our own Solar System. This investigator has already surveyed hundreds of young planetary systems using the ALMA array of millimeter telescopes. He will continue this work and search high resolution images from the array for signs of planet formation close to the parent stars. A graduate student and undergraduates will be involved in the work. The investigator will build a small radio telescope for use in undergraduate classes. He is also writing a textbook about the gas and dust from which stars form, and regularly speaks to classes at junior high schools.With baselines up to 13 km, ALMA can achieve a remarkable angular resolution of 0.02 arcseconds at a wavelength of one millimeter. This corresponds to radial scales of 1.5 au at the typical distance of nearby star-forming regions. It is now feasible to image disks and measure basic properties at the scales where most planets are found. Most studies to date have focused on the brightest disks to achieve high signal-to-noise ratios. However, the high optical depths in these bright disks prevent us from seeing into the innermost few au where most planets are found to reside. The PI will study fainter disks to investigate disk structure at solar system scales as their emission should not be saturated even in the smallest ALMA beam if they indeed have low masses.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

恒星和行星都是由气体和灰尘云形成的。天文学家最近发现，大多数恒星都有行星，但是许多行星系统看起来与我们自己的太阳系大不相同。该研究者已经使用毫米望远镜的Alma阵列对数百个年轻的行星系统进行了调查。他将继续这项工作，并从阵列中搜索高分辨率图像，以查找靠近父星的行星形成的迹象。研究生和本科生将参与这项工作。研究人员将建造一个小型射电望远镜，用于本科课程。他还写了一本教科书，讲述了恒星形成的气体和灰尘，并定期与初中的课程交谈。在最高13公里的基线的情况下，Alma可以在一毫米的波长下实现0.02弧形的显着角度分辨率。这对应于附近恒星形成区域的典型距离处的1.5 au的径向尺度。现在可以在发现大多数行星的尺度上测量磁盘并测量基本属性是可行的。迄今为止，大多数研究都集中在最明亮的磁盘上，以达到高信噪比。但是，这些明亮的磁盘中的高光学深度使我们无法看到大多数行星居住的最内向的AU。 PI将研究虚弱的磁盘以调查太阳系尺度上的磁盘结构，因为即使在最小的Alma梁中确实具有低质量，它们的排放也不应饱和。这奖反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来支持的。

项目成果

A Tale of Two Transition Disks: ALMA Long-baseline Observations of ISO-Oph 2 Reveal Two Closely Packed Nonaxisymmetric Rings and a ∼2 au Cavity

• DOI: 10.3847/2041-8213/abbcce
• 发表时间: 2020-10
• 期刊: The Astrophysical Journal Letters
• 作者: Camilo Gonz'alez-Ruilova;L. Cieza;A. Hales;S. P'erez;A. Zurlo;C. Arce-Tord;S. Casassus;H. C'anovas-H.

Protostellar and Protoplanetary Disk Masses in the Serpens Region

• DOI: 10.3847/1538-4357/ac8ff0
• 发表时间: 2022-04
• 期刊: The Astrophysical Journal
• 作者: Alexa R. Anderson;Jonathan P. Williams;N. Marel;C. Law;L. Ricci;J. Tobin;Simin Tong

The Anatomy of an Unusual Edge-on Protoplanetary Disk. II. Gas Temperature and a Warm Outer Region

• DOI: 10.3847/1538-3881/abeb1e
• 发表时间: 2021-03
• 期刊: The Astronomical Journal
• 作者: Christian Flores;G. Duchêne;S. Wolff;M. Villenave;K. Stapelfeldt;Jonathan P. Williams;C. Pinte;D. Padgett;M. Connelley;G. V. D. Plas;F. Menard;M. Perrin

Constraining disk evolution prescriptions of planet population synthesis models with observed disk masses and accretion rates

• DOI: 10.1051/0004-6361/201936488
• 发表时间: 2019-09
• 期刊: Astronomy & Astrophysics
• 影响因子: 6.5
• 作者: C. Manara;C. Mordasini;L. Testi;J. Williams;A. Miotello;G. Lodato;A. Emsenhuber

Are inner disc misalignments common? ALMA reveals an isotropic outer disc inclination distribution for young dipper stars

• DOI: 10.1093/mnras/stz3361
• 发表时间: 2020-02-01
• 期刊: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
• 影响因子: 4.8
• 作者: Ansdell, M.;Gaidos, E.;Rizzuto, A. C.
• 通讯作者: Rizzuto, A. C.