H-alpha Off-limb Carrington Synoptic Charts

Abstract:

Observations of solar prominences (and filaments) reveal complex structures, with significant differences in
morphology, lifetime, and complexity of their magnetic field environment. Studies of these
solar features are important for understanding not only their origin but also their role as precursors of
energetic events such as flares and coronal mass ejections.
The Global Oscillation Network Group (GONG) operated by the National Solar Observatory provides, among
other products, high-cadence broad-band intensity measurements centered in the core of
H-alpha spectral line. Prominences and filaments are quite visible in these 2Kx2K images, that have
been obtained since 2010. We recently
started a project to produce an archive of H-alpha off-limb Carrington Synoptic Charts to be used
for systematic studies of prominences. Charts are produced to show both spatial and temporal variability
of these features in four radius zones covering 1.01 to 1.11 solar radii. Here we describe the applied methodology
and show some preliminary results. Potential applications of interest to the solar and heliospheric communities
are also briefly discussed.