Photometric Studies of Magnetic Faculae and Photospheric Heat Flow

最近对航天器总太阳辐照度测量进行的分析非常令人信服地表明，活动区域和网络中的光斑对太阳周期内的辐照度变化十分重要。此外，光斑的红外测光技术对这些磁性结构中的加热机制提出了新的限制。在这里资助的计划的一个要素是在红外中进行准确的光度观测，以便能够更详细地研究结构中最深的层。将结果与光斑和太阳黑子通量管的MHD模型进行比较，应该是对导致光斑过度亮度的机制的一个强有力的新诊断。第二个目标是评估活动区和网络光斑对太阳周期总辐照度的贡献。它的目的是利用从存档的KPNO磁图获得的光球层分布，以及它们的磁通量与对比度之间的经验关系，这将通过可见光和近红外的光度学得出。这些研究的结果将大大促进对太阳光度调制机制及其与光球磁活动的关系的理解。总体目标是了解太阳光度变化，因为它们可能适用于陆地变化(例如。气候)。代理数据可能允许重建最近过去的太阳历史。

Recent analyses carried out on spacecraft total solar irradiance measurements have shown quite convincingly the importance of faculae in active regions and network for irradiance variation over the solar cycle. Also, infrared photometry of faculae places new constraints on the mechanisms responsible for heating in these magnetic structures. One element of the program funded here consists of accurate photometric observations in the infrared to enable a study of the deepest layers in the structures in more detail. Comparison of the results with mhd models of facular and sunspot flux tubes should be a powerful new diagnostic of the mechanisms that lead to facular excess brightness. A second aim is to evaluate the contribution of active region and network faculae to total irradiance over the solar cycle. It is intended to use photospheric distribution obtained from archival KPNO magnetograms, and an empirical relation between their magnetic flux and contrast that will be derived through photometry in the visible and near IR. The results of these studies should considerably advance understanding of solar luminosity modulation mechanisms and their relation to photospheric magnetic activity. The overall aim is to understand solar luminosity variations as they might apply to terrestrial changes (eg. climate). Proxy data might permit reconstruction of solar history in the recent past.