SunRISE Proposal: Precision Solar Disk Photometry--A Tool for Understanding Changes in the Sun's Luminosity

这项建议将继续不断努力， 测量太阳表面亮度的大范围变化 太阳圆盘 一种独特的专业仪器， 大熊星座太阳观测站已经建成， 初步数据已经获得。 一系列的 精确的光度数据，PI将进行一些 调查：1）PI将比较测量的纬度-和 随时间变化的亮度变化 不断的测量。 更完整的空间信息 从光度计得到的将用于更好地了解 负责短期和长期太阳能的物理机制 光度变化 例如，测量的平均纬度-和 >-依赖亮度结构（这里>是通常的日心 角）与测量的光斑对比度函数一起，可以 直接测量光斑对太阳辐射的贡献 光度变化。 此外，如果太阳的光度变化 确定（使用我们的光度数据）仅限于 活动纬度，然后精确的地面测量， 这里提出的那些可以成为空间的极好替代品- 基于太阳常数测量，当后者不可用时。 2)PI将更好地测量极赤道 温度差，做一些努力，以分开的周期- 依赖的磁信号从假定的时间无关） 差动旋转信号 这样的测量将限制 太阳的差异旋转模型。 3)pi将 精确测量太阳极附近的亮度变化， 为了更好地了解极地磁场 和极性光斑。 对大范围亮度进行精确测量 太阳的结构是迄今为止一个基本上未被探索的领域， research. 测量数据集可以帮助 对理解和监测太阳的活动有着重要意义 光度变化 #

This proposal will continue an ongoing effort to precisely measure large-scale solar surface brightness variations across the solar disk. A unique and specialized instrument to make these measurements has been constructed at Big Bear Solar Observatory, and preliminary data have been acquired. With a timeseries of precision photometric data, the PI will conduct a number of investigations: 1) The PI will compare measured latitude- and time-dependent brightness variations with time-dependent solar constant measurements. The more complete spatial information gotten from the photometer will be used to better understand the physical mechanisms responsible for short- and long-term solar luminosity variations. For example, measured average latitude- and >-dependent brightness structure (here > is the usual heliocentric angle), together with the measured facular contrast function, can be used to directly measure the contribution of faculae to solar luminosity changes. Further, if the Sun's luminosity variations are determined (using our photometric data) to be confined to the active latitudes, then precision ground-based measurements such as those proposed here could make an excellent substitute for space- based solar constant measurements, when the latter are unavailable. 2) The PI will make a better measurement of the pole-equator temperature difference, making some effort to separate the cycle- dependent magnetic signals from the presumably time-independent) differential rotation signal. Such a measurement will constrain models of the Sun's differential rotation. 3) The PI will accurately measure brightness variations near the solar pole, in order to get a better understanding of the polar magnetic fields and polar faculae. Making precision measurements of the large-scale brightness structure of the Sun is to date a largely unexplored area of research. The data set of measurements could contribute significantly to the understanding and monitoring of the Sun's luminosity variations. #