Understanding Magnetic Fields in the Milky Way Galaxy and in Star Forming Clouds

了解银河系和恒星形成云中的磁场

• 批准号: 1814531
• 负责人: Dan Clemens
• 金额: $ 49.95万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-10-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1814531&HistoricalAwards=false
• 关键词: Understanding; Magnetic; Fields; Milky; Way

The magnetic field that threads through the gas and dust in the Milky Way Galaxy has been mapped by the awardees using their own instrument, Mimir. Mimir was built over a decade ago with support from NSF, NASA, and the W.M. Keck Foundation. Mimir measures the polarization of infrared light produced by the dust in the Milky Way. Most of the dust (and gas) is found in large clouds that drift through space. These clouds collapse under their own weight to form new stars. Careful analysis of the polarized light from these dusty clouds teaches us about the magnetic fields that control the shapes and sizes of each cloud. The magnetic fields also affect the way the clouds collapse to make stars. Much of the data has already been collected. The awardees now need funding to support the careful examination of the data. The data will be used, together with observations from other telescopes such as the Stratospheric Observatory for Infrared Astronomy (SOFIA) and NSF's Atacama Large Millimeter Array (ALMA), to test models of Milky Way clouds and star formation. Students from Boston University will be trained on how to take the Mimir data and examine the polarimetry results. A graduate student will use Mimir, SOFIA and ALMA data to complete their PhD project. Undergraduate students (including many who are not majoring in astronomy) will be brought to Arizona to operate Mimir on the Perkins telescope. These telescope trips often inspire students to follow careers in science. Other students will participate in the observing by videoconference. The team will also pursue outreach opportunities at the Boston Museum of Science, where the Department of Astronomy at Boston University holds weekly open nights. Mimir is being used by the awardees to survey the magnetic field structure along the galactic plane and in various star forming regions via background starlight polarization measurements in the near-infrared H-band. Their survey, dubbed the Galactic Plane Infrared Polarization Survey (GPIPS), covers 76 square degrees of the inner disk and probes up to 20 magnitudes of extinction. Complementary mid-IR polarization measurements are used to probe star forming clouds up to 50 magnitudes of extinction. Various well-known techniques (Zeeman splitting, the Davis-Chandrasekhar-Fermi method, etc.) will be used on these and complementary archival data to infer field strengths and orientations across the surveyed areas. Analysis of these data will provide quantitative tests of models of galactic B-fields and constrain theories of star formation in dense molecular clouds.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.

获奖者使用他们自己的仪器Mimir绘制了穿过银河系气体和尘埃的磁场图。MIMIR是十多年前在NSF、NASA和W.M.凯克基金会的支持下建造的。MIMIR测量了银河系尘埃产生的红外光的偏振。大部分尘埃(和气体)存在于漂浮在太空中的大型云层中。这些云在自身重量的作用下坍塌，形成新的恒星。仔细分析来自这些尘埃云的偏振光，我们就会了解控制每一颗云的形状和大小的磁场。磁场还会影响星云坍塌形成恒星的方式。大部分数据已经收集完毕。获奖者现在需要资金来支持对数据的仔细检查。这些数据将与红外天文平流层天文台(SOFIA)和美国国家科学基金会的阿塔卡马大毫米阵列(ALMA)等其他望远镜的观测结果一起用于测试银河系云和恒星形成的模型。波士顿大学的学生将接受培训，学习如何获取MIMIR数据并检查偏振测量结果。一名研究生将使用Mimir、Sofia和ALMA的数据来完成他们的博士项目。本科生(包括许多非天文学专业的学生)将被带到亚利桑那州，在珀金斯望远镜上操作MIMIR。这些望远镜之旅往往会激励学生追随科学职业。其他学生将通过视频会议参与观察。该团队还将在波士顿科学博物馆寻求外展机会，波士顿大学天文学系每周都会在那里举办开放日。获奖者正在使用MIMIR通过近红外H波段的背景星光偏振测量来测量沿银河系平面和不同恒星形成区域的磁场结构。他们的测量被称为银河平面红外偏振测量(GPIPS)，覆盖了内盘76平方度的区域，探测到了高达20等的灭绝。互补的中红外偏振测量被用来探测恒星形成的云，最高可达50级的消光。各种著名的技术(塞曼分裂、Davis-Chandrasekhar-Fermi方法等)将在这些和补充的档案数据上使用，以推断调查地区的实地力量和方向。对这些数据的分析将提供对星系B场模型的定量测试，并约束致密分子云中恒星形成的理论。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Multiwavelength Polarimetry of the Filamentary Cloud IC 5146. II. Magnetic Field Structures

丝状云 IC 5146 的多波长偏振测定。 II．

• DOI: 10.3847/1538-4357/ab5c1c
• 发表时间: 2020
• 期刊: The Astrophysical Journal
• 作者: Wang, Jia-Wei;Lai, Shih-Ping;Clemens, Dan P.;Koch, Patrick M.;Eswaraiah, Chakali;Chen, Wen-Ping;Pandey, Anil K.
• 通讯作者: Pandey, Anil K.

Magnetic Fields and Star Formation around H II Regions: The S235 Complex

• DOI: 10.3847/1538-4357/abe9b1
• 发表时间: 2021-03
• 期刊: The Astrophysical Journal
• 作者: R. Devaraj;D. Clemens;L. Dewangan;A. Luna;T. Ray;J. Mackey

The Galactic Plane Infrared Polarization Survey (GPIPS): Data Release 4

• DOI: 10.3847/1538-4365/ab9f30
• 发表时间: 2012-06
• 期刊: The Astrophysical Journal Supplement Series
• 作者: D. Clemens;L. Cashman;C. Cerny;A. M. El-Batal;K. Jameson;R. Marchwinski;J. Montgomery;M. Pavel;A. Pinnick;B. Taylor

Magnetized filamentary gas flows feeding the young embedded cluster in Serpens South

• DOI: 10.1038/s41550-020-1172-6
• 发表时间: 2020-08
• 期刊: Nature Astronomy
• 影响因子: 14.1
• 作者: T. Pillai;D. Clemens;S. Reissl;P. Myers;J. Kauffmann;E. Lopez-Rodriguez;F. Alves;G. Franco;J. Henshaw;K. Menten;F. Nakamura;D. Seifried;K. Sugitani;H. Wiesemeyer

Probing Interstellar Grain Growth through Polarimetry in the Taurus Cloud Complex

• DOI: 10.3847/1538-4357/abc6b0
• 发表时间: 2020-10
• 期刊: The Astrophysical Journal
• 作者: J. Vaillancourt;B. Andersson;D. Clemens;V. Piirola;Thiem C. Hoang;E. Becklin;Miranda Caputo Lincoln Laboratory-Miranda-Capu