SHARP Near-Real-Time Cylindrical-Equal-Area Data

SHARP Near Real Time data in the Cylindrical Equal Area (CEA) Cartesian coordinate.

SHARP stands for Space-weather HMI Active Region Patch. A SHARP is a DRMS series that contains (1) various space-weather quantities calculated from the photospheric vector magnetogram data and stored as FITS header keywords, and (2) 31 data segments (described in detail below), including each component of the vector magnetic field, the line-of-sight magnetic field, continuum intensity, doppler velocity, error maps and bitmaps. The data segments are not full-disk; rather, they are partial-disk, automatically-identified active region patches. SHARPs are calculated every 12 minutes. Often, there is more than one active region on the solar disk at any given time. Thus, SHARPs are indexed by two prime keys: time, T_REC, and HMI Active Region Patch Number, HARPNUM.

The hmi.sharp_720s_cea_nrt and hmi.sharp_cea_720s data have been projected and remapped to a Cylindrical Equal Area (CEA) Cartesian coordinate system centered on the tracked active region. The size of the nrt regions will evolve with time. At each time step the definitive SHARPs will enclose the maximum extent of the region during it's disk passage. The three prime vector components are Bx, By, and Bz. HARP maps of 8 additional quantities are also provided at each time step: the three estimated component errors, the line-of-sight magnetogram, a Dopplergram, the continuum intensity, a map of the active pixels, and an estimate of the confidence in the disambiguation.

SHARP近实时数据集位于圆柱等面积（CEA）笛卡尔坐标系中。SHARP代表空间天气HMI活动区域块。SHARP是一系列DRMS数据，包括（1）从光球矢量磁图数据计算得出的各种空间天气量，并以FITS头关键字的形式存储，以及（2）31个数据段（以下将详细描述），包括矢量磁场的各个分量、视向磁场、连续强度、多普勒速度、误差图和位图。这些数据段不是全圆盘，而是自动识别的部分圆盘活动区域块。SHARPs每12分钟计算一次。通常，在任一给定时间，太阳盘上会有多个活动区域。因此，SHARPs通过两个主要键进行索引：时间，T_REC，和HMI活动区域块编号，HARPNUM。

hmi.sharp_720s_cea_nrt和hmi.sharp_cea_720s数据已投影并重映射到以追踪活动区域为中心的圆柱等面积（CEA）笛卡尔坐标系。nrt区域的大小将随时间演变。在每一步时间中，最终的SHARPs将包围区域在磁盘上的最大范围。三个主要矢量分量是Bx、By和Bz。在每一步时间中，还提供了8个其他量的HARP图：三个估计分量误差、视向磁图、多普勒图、连续强度、活动像素图和区分置信度估计。