Active region magnetograms for solar flare prediction: Extra images dataset

In this dataset, we provide a comprehensive collection of magnetograms from the National Aeronautics and Space Administration's (NASA's) Solar Dynamics Observatory (SDO).  The dataset incorporates data from three sources and provides SDO Helioseismic and Magnetic Imager (HMI) magnetograms of solar active regions as well as labels of corresponding flaring activity.  This dataset will be useful for image analysis or solar physics research related to magnetic structure, its evolution over time, and its relation to solar flares.  The dataset will be of interest to those researchers investigating automated solar flare prediction methods, including supervised and unsupervised machine learning (classical and deep), binary and multi-class classification, and regression.  This dataset contains those images that were removed from the preconfigured datasets (see usage notes below).

Methods
This dataset incorporates data from three main sources. First, in order to focus the image collection on ARs, we used the NOAA Space Weather Prediction Center (SWPC) Solar Region Summaries (SRS) (ftp://ftp.swpc.noaa.gov/pub/warehouse/) and parsed those text data to extract the date an AR appeared on disk and the number of days it was visible on disk.  Additionally, the SRS provide latitude and longitude of ARs which we use to postprocess the dataset. Second, we download magnetogram images from SDO/HMI using the Joint Science Operations Center (JSOC) interface (http://jsoc.stanford.edu/ajax/lookdata.html) at a cadence of 720 seconds, centered at the NOAA AR centroid (tracked according to the Carrington rate), and with a spatial extent of 600x600 pixels. Third, we used the SWPC Event Reports (ER) (ftp://ftp.swpc.noaa.gov/pub/warehouse/) to extract the AR number, peak flare time, and flare size in order to provide labels for those researchers investigating a supervised classification or regression problem.

本数据集收录了美国国家航空航天局（National Aeronautics and Space Administration, NASA）太阳动力学天文台（Solar Dynamics Observatory, SDO）的完整磁场图集合。该数据集整合了三类来源的数据，包含太阳活动区的SDO日震与磁场成像仪（Helioseismic and Magnetic Imager, HMI）磁场图，以及对应的耀斑活动标注。
本数据集可应用于与磁场结构、其时间演化规律及其与太阳耀斑的关联相关的图像分析或太阳物理研究。对于致力于自动化太阳耀斑预测方法探索的科研人员而言，本数据集具备较高的研究价值，其覆盖的研究方向涵盖监督与无监督机器学习（经典机器学习与深度学习）、二元分类与多分类任务以及回归分析。本数据集包含从预配置数据集（详见下文使用说明）中筛选得到的图像。

方法
本数据集整合了三类核心来源的数据。
第一，为将图像采集范围聚焦于太阳活动区，我们使用了美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）空间天气预测中心（Space Weather Prediction Center, SWPC）发布的《太阳区域摘要》（Solar Region Summaries, SRS）（数据地址：ftp://ftp.swpc.noaa.gov/pub/warehouse/），并对其中的文本数据进行解析，以提取太阳活动区在日面上出现的日期及可见天数。此外，《太阳区域摘要》还提供了太阳活动区的经纬度坐标，我们将其用于数据集的后处理流程。
第二，我们通过联合科学运行中心（Joint Science Operations Center, JSOC）的官方接口（http://jsoc.stanford.edu/ajax/lookdata.html），以720秒的采样频率从SDO/HMI下载磁场图图像。图像中心对齐于NOAA太阳活动区的质心（按卡林顿自转速率进行跟踪），空间尺寸为600×600像素。
第三，我们借助SWPC事件报告（Event Reports, ER）（数据地址：ftp://ftp.swpc.noaa.gov/pub/warehouse/）提取太阳活动区编号、耀斑峰值时刻与耀斑规模信息，以此为开展监督分类或回归任务的研究人员提供标注数据。