A Novel and Powerful Way to Measure Coronal Magnetic Fields for the DKIST Era

太阳物理学中尚未解决的主要问题之一是太阳日冕如何被加热到100多万度的温度。该项目将在该机构的边缘、活跃区域和日冕无散射天文台（SOLARC）望远镜上开发和安装新的仪器。该仪器将在红外线下工作，并将利用一种新的方法来观察日冕中的弱发射线。这些测量结果将用于推导日冕中的磁场，然后将其与预测日冕加热的现有数值模型进行比较。这个项目将支持下一代太阳科学家的培训。该项目将包括一名博士后研究员，并计划吸纳研究生和本科生的暑期实习生。在这个项目中，PI将建造一个安装在SOLARC望远镜上的新仪器。这种新仪器将利用一种基于允许-禁止线对和汉勒效应的新方法，这比以前的技术有两个显著的优势。首先，它只依赖于测量线极化发射信号，通常比以前使用的圆极化发射线大两个（或更多）数量级。其次，它使用较长的红外（IR）波长的发射线，在那里来自地球大气的散射光大大减少。然后将观测到的日冕矢量磁场与磁流体动力学（MHD）模型进行比较，以更好地了解日冕内部的加热机制。开发工作还应该提供一种强大的方法，可以直接应用于Daniel K. Inouye太阳望远镜（DKIST）红外仪器的高空间分辨率能力。

One of the major unsolved problems in solar physics is the question regarding how the solar corona is heated to temperatures over a million degrees. This project will develop and install new instrumentation on the institution's Scatter-free Observatory for Limb, Active Regions and Coronae (SOLARC) telescope. This instrumentation will operate in the infrared and will take advantage of a new approach to observing weak emission lines in the corona. These measurements will be used to derive the magnetic fields in the corona which will, in turn, be compared to existing numerical models that predict coronal heating. This project will support the training of the next generation of solar scientists. The PI will involve a postdoctoral researcher in the project and also plans to incorporate summer interns on the graduate and undergraduate level. In this project, the PI will construct a new instrument to be installed on the SOLARC telescope. This new instrument will take advantage of a novel approach that is based on permitted-forbidden line pairs and the Hanle effect, which has two significant advantages over previous techniques. First, it only relies on measuring linearly polarized emission signals which are typically two (or more) orders of magnitude larger than previously used circularly polarized emission lines. Second, it uses emission lines at longer infrared (IR) wavelengths where the scattered light from Earth's atmosphere is greatly reduced. The observed coronal vector magnetic fields will then be compared to magnetohydrodynamic (MHD) models to better understand the heating mechanisms within the corona. The development effort should also provide a powerful method that can be applied directly to the high spatial resolution capabilities of the Daniel K. Inouye Solar Telescope's (DKIST's) IR instruments.