An Observational Study of Magnetic Fields in the Galaxy and Beyond

特洛兰博士研究的主要目标是测量许多星际环境中的磁场强度，并利用这些信息更好地了解磁场在我们的银河系和其他星系中的作用。人们很早就知道星际物质受到弱磁场的渗透。人们还知道，这些场可以在星际物质的动力学和演化中发挥重要作用，包括恒星的形成过程。目前还不清楚的是，在各种星际环境中，磁场的强度有多大。对领域优势的详细了解很重要。这些磁场对星际云的影响很大程度上取决于磁能与星云中其他相关能量的比率。增加场强和增加气体密度之间的关系可以揭示更多关于收缩过程的细节。在银河系尺度上，磁场强度可能与星系中新恒星形成的总体速度密切相关。特洛兰试图扩大先前对射电频率塞曼效应的观察，塞曼效应是唯一已知的测量星际物质局部区域磁场强度的技术。最近阿雷西博300米射电望远镜的升级和即将完成的100米绿岸望远镜为研究星际磁场强度提供了许多新的机会。在这个项目中，塞曼效应将在各种星际物种的谱线中进行研究，包括HI、OH(基态和激发态)、CCS、C4H、CH和H2O。这个项目应该会大大增加我们对各种银河系星际环境中的磁场的了解。该项目还可能提供第一次直接测量我们所在星系以外的星系中的磁场。

The principal objective of Dr. Troland's research is to measure magnetic field strengths in many interstellar environments and to use this information to better understand the role of magnetic fields in our Galaxy and in others. It has long been known that interstellar material is permeated by weak magnetic fields. It is also known that these fields can play an important role in the dynamics and evolution of interstellar material, including the process of star formation. What is not well known is the strength of the field in a wide variety of interstellar environments. A detailed knowledge of field strengths is important. The effects of these fields on interstellar clouds depend crucially upon the ratio of magnetic energies to other relevant energies in the clouds. The relationship between increasing field strength and increasing gas density can reveal much about the details of the contraction process. On the galactic scale, magnetic field strengths may be closely related to the overall rate at which new stars form in a galaxy.Dr. Troland seeks to expand upon previous observations of the radio frequencyZeeman effect, the only known technique for measuring magnetic field strengths inlocalized regions of interstellar material. The recent upgrade of the Arecibo 300 meter radio telescope and the impending completion of the 100m Green Bank Telescope offermany new opportunities to study interstellar magnetic field strengths. In this project, theZeeman effect will be studied in spectral lines of a variety of interstellar species includingHI, OH (ground and excited states), CCS, C4H, CH and H2O. This project shouldprovide a significant increase in our knowledge of magnetic fields in a wide variety ofgalactic interstellar environments. This project may also provide the first directmeasurements of magnetic fields in galaxies beyond our own.