Measuring Cosmic Magnetism with the Low Frequency Radio Array

这项提议计划通过亚利桑那州立大学和德国长波联盟的合作，对宇宙磁性进行低频无线电测量。每年，该计划将资助两名一年级研究生和五名高级本科生，他们将利用欧洲一种引人注目的新射电望远镜--低频阵列(LOFAR)进行研究。由于其灵敏度、分辨率和频率覆盖范围，LOFAR将允许星际磁场测量比以前更好的数量级。磁场贯穿宇宙，设定星系中恒星形成的标准，控制星系团的演化，并改变所有星系形成的星际介质。然而，人们对它们的特性知之甚少。LOFAR是新一代望远镜中的第一台，它工作在10至240兆赫的极低频率范围内。磁场主要是通过它们与宇宙射线的相互作用来探测的，只有这些低频望远镜才能在远离宇宙射线源和银河系空间深处进行灵敏的测量，这些低频对应于低宇宙线能量。有了这个了不起的新工具，IRES学生开展的项目将有助于打开一扇了解磁性宇宙的新窗口。在星系尺度上，他们将探索恒星形成和磁性之间的联系，以及围绕星系的磁场的起源。在星系团尺度上，他们将探索热跟踪介质的未知物理，以及在其中发现的同步辐射气泡的演化。在宇宙尺度上，他们将揭示连接所有星系的气网的磁性。他们将共同填补一个基本问题的关键部分：宇宙在最大尺度上的结构是什么？

Part 1This proposal plans to carry out low-frequency radio measurements of cosmic magnetism through a collaboration between Arizona State University and the German Long Wavelength Consortium. Each year, the program will fund two first-year graduate students and five advanced undergraduates, who will carry out research with the Low Frequency Array (LOFAR), a remarkable new European radio telescope. Due to its sensitivity, resolution, and frequency coverage, LOFAR will allow for intergalactic magnetic field measurements orders of magnitude better than previously possible.Part 2Magnetic fields thread the Universe, setting the criteria for star formation in galaxies, controlling the evolution of galaxy clusters, and altering the intergalactic medium from which all galaxies formed. Yet very little is known about their properties.LOFAR is the first of a new generation of telescopes that operates in the extremely low frequency range between 10 and 240 MHz. Magnetic fields are primarily detected by their interactions with cosmic rays, and only telescopes at these low frequencies, whichcorrespond to low cosmic ray energies, are able to make sensitive measurements far away from cosmic ray sources and out in the depths of intergalactic space. With this remarkable new tool, the projects carried out by IRES students will help to open a new window on the magnetic universe. On galaxy scales, they will probe the connection between star formation and magnetism and the origin of the magnetic fields that surround galaxies. On galaxy cluster scales, they will probe the unknown physics of the hotintracluster medium and the evolution of the synchrotron emitting bubbles found within it. On cosmic scales they will uncover the magnetic properties of the web of gas that connects all galaxies. Together they will be filling in a key piece of the fundamental question: what is the structure of the Universe on the largest scales?