Automatic Detection of Magnetic delta in Sunspot Groups

TL;DR

This paper introduces SMART-DF, an automated system that detects magnetic delta sunspot groups in near-real-time using SDO/HMI data, improving flare prediction by early identification of complex active regions.

Contribution

The paper presents a novel automated algorithm, SMART-DF, for detecting magnetic delta configurations in sunspot groups using magnetogram data, enhancing real-time flare forecasting capabilities.

Findings

Detected 21 of 23 NOAA-identified delta spots in 2011-2012.

Identified 5 delta regions not reported by NOAA.

Operates in near-real-time for early flare prediction.

Abstract

Large and magnetically complex sunspot groups are known to be associated with flares. To date, the Mount Wilson scheme has been used to classify sunspot groups based on their morphological and magnetic properties. The most flare prolific class, the delta sunspot-group, is characterised by opposite polarity umbrae within a common penumbra, separated by less than 2 degrees. In this article, we present a new system, called the Solar Monitor Active Region Tracker - Delta Finder (SMART-DF), that can be used to automatically detect and classify magnetic deltas in near-realtime. Using continuum images and magnetograms from the Helioseismic and Magnetic Imager (HMI) onboard NASA's Solar Dynamics Observatory (SDO), we first estimate distances between opposite polarity umbrae. Opposite polarity pairs having distances of less that 2 degrees are then identified, and if these pairs are found to share a common penumbra, they are identified as a magnetic delta configuration. The algorithm was compared to manual delta detections reported by the Space Weather Prediction Center (SWPC), operated by the National Oceanic and Atmospheric Administration (NOAA). SMART-DF detected 21 out of 23 active regions (ARs) that were marked as delta spots by NOAA during 2011 - 2012 (within +/- 60 degrees longitude). SMART-DF in addition detected five ARs which were not announced as delta spots by NOAA. The near-relatime operation of SMART-DF resulted in many deltas being identified in advance of NOAA's daily notification. SMART-DF will be integrated with SolarMonitor (www.solarmonitor.org) and the near-realtime information will be available to the public.