WoU-MMA: Linear and Circular Polarization as a Probe of the Relativistic Jets of Blazars

WoU-MMA：线偏振和圆偏振作为耀变体相对论射流的探针

• 批准号: 2108622
• 负责人: Alan Marscher
• 金额: $ 51.92万
• 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: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2108622&HistoricalAwards=false
• 关键词: WoU; MMA; Linear; Circular; Polarization

This project will study blazars, the most luminous long-lived objects in the universe. Blazars are powered by matter from stars and interstellar gas clouds falling toward super-massive black holes at the centers of some galaxies. The infalling matter and rotation of the black hole create jets of high-energy particles and magnetic fields that flow outward at nearly the speed of light. The project will help to explain (1) how the jets are formed and accelerated, (2) whether the radiating particles are mostly "normal" matter or equal amounts of matter and anti-matter, and (3) how much energy is contained in the jets. The project will utilize multi-messenger observations at different wavelengths to probe the physical conditions in the jets of nearly 40 blazars. The project will improve our understanding of extreme conditions in the universe. It also will contribute to public appreciation of science through presentations at libraries and high schools. It will also advance the scientific training of students through visits of Native-American school students to Boston University’s Perkins Telescope, involvement of undergraduate students in the data analysis and interpretation, availability of a free textbook on extragalactic astronomy and cosmology written by the PI, and development of an exercise for college-level introductory astronomy classes. This award addresses/advances the goals of the Windows on the Universe Big Idea. Blazars are galactic nuclei with relativistic jets of magnetized, high-energy plasma produced by actively accreting super-massive black holes. The study will provide detailed information needed to characterize the magnetic field pattern in blazar jets, which is directly related to the dynamics of the jets. This will be accomplished by measuring the polarization of blazar jets both in extremely high-resolution images at microwave frequencies of 43 and 86 GHz, and from the entire jet at visible and X-ray frequencies. Cross-comparison of the linear polarization of blazars from millimeter-wave to X-ray wavelengths will trace the magnetic field pattern from about 10 parsecs to sub-parsec scales and test hypotheses regarding the particle acceleration processes that cause the extreme luminosities and variability of blazars. Comparison of the 43 and 86 GHz linear and circular polarization with computer simulations will facilitate a determination of both the relative amount of anti-matter (positrons) and the total kinetic power of the jets, which controls the impact that the jet can have on its galactic environment. The amount of anti-matter determines whether the particles in the jet are produced at the base of the jet near the black hole or injected from outside the jet. The project will train undergraduate STEM students in scientific data analysis and interpretation, make available a free textbook on extragalactic astronomy and cosmology written by the PI, and develop an exercise for college-level introductory astronomy classes.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.

这个项目将研究耀变体，这是宇宙中最明亮、寿命最长的物体。耀变体的动力来自恒星和星际气体云的物质，这些物质落向一些星系中心的超大质量黑洞。落入黑洞的物质和黑洞的旋转产生了高能粒子和磁场的喷流，这些粒子和磁场以接近光速的速度向外流动。该项目将有助于解释(1)喷流是如何形成和加速的；(2)辐射粒子主要是“正常”物质还是等量的物质和反物质；(3)喷流中包含多少能量。该项目将利用不同波长的多信使观测来探测近40个耀变体喷流的物理状况。该项目将提高我们对宇宙极端条件的理解。它还将通过在图书馆和高中的演讲，促进公众对科学的欣赏。它还将通过以下方式促进学生的科学训练：让美国原住民学校的学生参观波士顿大学的珀金斯望远镜，让本科生参与数据分析和解释，提供由PI编写的免费星系外天文学和宇宙学教科书，以及为大学水平的天文学入门课程开发练习。该奖项旨在解决/推进宇宙之窗大构想的目标。耀变体是由活跃的超大质量黑洞产生的磁化高能等离子体的相对论喷流形成的星系核。这项研究将提供描述耀变体喷流磁场模式所需的详细信息，这与喷流的动力学直接相关。这将通过测量43 GHz和86 GHz微波频率的极高分辨率图像以及可见光和x射线频率的整个喷流的偏振来完成。对耀变体从毫米波到x射线波长的线偏振进行交叉比较，将追踪从大约10秒差距到亚秒差距尺度的磁场模式，并测试有关导致耀变体极端亮度和可变性的粒子加速过程的假设。将43 GHz和86 GHz的线偏振和圆偏振与计算机模拟进行比较，将有助于确定反物质（正电子）的相对数量和喷流的总动能，后者控制着喷流对银河系环境的影响。反物质的数量决定了喷流中的粒子是在靠近黑洞的喷流底部产生，还是从喷流外部注入。该项目将培训STEM专业的本科生进行科学数据分析和解释，提供PI编写的免费星系外天文学和宇宙学教科书，并为大学水平的天文学入门课程开发练习。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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

Observations of 4U 1626-67 with the Imaging X-Ray Polarimetry Explorer

使用成像 X 射线偏振测量探测器观察 4U 1626-67

• DOI: 10.3847/1538-4357/ac98c2
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Marshall Herman L. et al.

X-ray polarimetry of X-ray pulsar X Persei: another orthogonal rotator?

X射线脉冲星X Persei的X射线偏振测量：另一个正交旋转体？

• DOI: 10.1093/mnras/stad1961
• 发表时间: 2023
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Mushtukov, A A;Tsygankov, S S;Poutanen, J;Doroshenko, V;Salganik, A;Costa, E;Marco, A Di;Heyl, J;Monaca, F La;Lutovinov, A A
• 通讯作者: Lutovinov, A A

X-Ray Polarization Observations of BL Lacertae

BL 蜥蜴的 X 射线偏振观测

• DOI: 10.3847/2041-8213/aca281
• 发表时间: 2022
• 期刊: The Astrophysical Journal Letters
• 作者: Middei Riccardo;Liodakis Ioannis;Perri Matteo;Uemura Makoto;他144名
• 通讯作者: 他144名

Polarized x-rays from a magnetar

来自磁星的偏振 X 射线

• DOI: 10.1126/science.add0080
• 发表时间: 2022
• 期刊: Science
• 影响因子: 56.9
• 作者: Hasegawa Takeshi;Greve Annika;Gravley Darren M.;Kusu Chie;Kaneda Yasuaki;Shibata Shohei;Okada Makoto;K?sik Szabolcs;Mochizuki Nobutatsu;Turner Gillian;Taverna Roberto et al.
• 通讯作者: Taverna Roberto et al.

X-ray polarization evidence for a 200-year-old flare of Sgr A*

200 年前 Sgr A* 耀斑的 X 射线偏振证据

• DOI: 10.1038/s41586-023-06064-x
• 发表时间: 2023
• 期刊: Nature
• 影响因子: 64.8
• 作者: Marin, Frédéric;Churazov, Eugene;Khabibullin, Ildar;Ferrazzoli, Riccardo;Di Gesu, Laura;Barnouin, Thibault;Di Marco, Alessandro;Middei, Riccardo;Vikhlinin, Alexey;Costa, Enrico
• 通讯作者: Costa, Enrico