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Related papers: Automatic Detection of Magnetic delta in Sunspot G…

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Delta ($\delta$)-spots are active regions (ARs) in which positive and negative umbrae share a penumbra. They are known to be the source of strong flares. We introduce a new quantity, the degree of $\delta$ (Do$\delta$), to measure the…

Solar and Stellar Astrophysics · Physics 2022-10-26 A. A. Norton , P. J. Levens , K. J. Knizhnik , M. G. Linton , Y. Liu

Since the Solar Dynamics Observatory (SDO) began recording ~ 1 TB of data per day, there has been an increased need to automatically extract features and events for further analysis. Here we compare the overall detection performance,…

Solar and Stellar Astrophysics · Physics 2011-09-05 Cis Verbeeck , Paul A. Higgins , Tufan Colak , Fraser T. Watson , Veronique Delouille , Benjamin Mampaey , Rami Qahwaji

We study the predictive capabilities of magnetic feature properties (MF) generated by Solar Monitor Active Region Tracker (SMART) for solar flare forecasting from two datasets: the full dataset of SMART detections from 1996 to 2010 that has…

Solar and Stellar Astrophysics · Physics 2018-12-07 Katarina Domijan , D. Shaun Bloomfield , Francois Pitie

Sunspots, which harbor both magnetic polarities within one penumbra, are called delta-spots. They are often associated with flares. Nevertheless, there are only very few detailed observations of the spatially resolved magnetic field…

Solar and Stellar Astrophysics · Physics 2013-12-19 Horst Balthasar , Christian Beck , Rohan E. Louis , Meetu Verma , Carsten Denker

We present an automated system for detecting, tracking, and cataloging emerging active regions throughout their evolution and decay using SOHO Michelson Doppler Interferometer (MDI) magnetograms. The SolarMonitor Active Region Tracking…

Solar and Stellar Astrophysics · Physics 2010-07-01 Paul A. Higgins , Peter T. Gallagher , R. T. James McAteer , D. Shaun Bloomfield

The automated detection of solar features is a technique which is relatively underused but if we are to keep up with the flow of data from spacecraft such as the recently launched Solar Dynamics Observatory, then such techniques will be…

Solar and Stellar Astrophysics · Physics 2015-05-20 Fraser Watson , Lyndsay Fletcher

Active regions (AR) appearing on the surface of the Sun are classified into $\alpha$, $\beta$, $\gamma$, and $\delta$ by the rules of the Mount Wilson Observatory, California on the basis of their topological complexity. Amongst these, the…

Solar and Stellar Astrophysics · Physics 2016-03-09 Piyali Chatterjee , Viggo Hansteen , Mats Carlsson

In this dataset we provide a comprehensive collection of magnetograms (images quantifying the strength of the magnetic field) from the National Aeronautics and Space Administration's (NASA's) Solar Dynamics Observatory (SDO). The dataset…

Solar and Stellar Astrophysics · Physics 2024-02-13 Laura E. Boucheron , Ty Vincent , Jeremy A. Grajeda , Ellery Wuest

Using SDO/HMI and SDO/AIA data for sunspot groups of the 24th solar cycle, we analyzed magnetic properties and He II 304 emission in leading and following sunspots separately. Simultaneous examination of umbral magnetic properties and…

Solar and Stellar Astrophysics · Physics 2015-11-24 Iu. S. Zagainova , V. G. Fainshtein , V. N. Obridko

$\delta$-sunspots, with highly complex magnetic structures, are very productive in energetic eruptive events, such as X-class flares and homologous eruptions. We here study the formation of such complex magnetic structures by numerical…

Solar and Stellar Astrophysics · Physics 2015-06-17 Fang Fang , Yuhong Fan

Sunspots harboring umbrae of both magnetic polarities within a common penumbra (delta-spots) are often but not always related to flares. We present first near-infrared (NIR) observations (Fe I 1078.3 nm and Si I 1078.6 nm spectra) obtained…

Solar and Stellar Astrophysics · Physics 2015-06-18 H. Balthasar , C. Beck , R. E. Louis , M. Verma , C. Denker

Active region NOAA 11035 appeared in December 2009, early in the new solar activity cycle. This region achieved a delta sunspot ($\delta$-spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and…

Solar and Stellar Astrophysics · Physics 2016-02-17 Sarah A. Jaeggli

Sunspots, as seen in white light or continuum images, are associated with regions of high magnetic activity on the Sun, visible on magnetogram images. Their complexity is correlated with explosive solar activity and so classifying these…

Computer Vision and Pattern Recognition · Computer Science 2015-03-16 Kevin R. Moon , Jimmy J. Li , Veronique Delouille , Fraser Watson , Alfred O. Hero

The purpose of this letter is to address a blind-spot in our knowledge of solar active region statistics. To the best of our knowledge there are no published results showing the variation of the Mount Wilson magnetic classifications as a…

Solar and Stellar Astrophysics · Physics 2016-03-23 Sarah A. Jaeggli , Aimee A. Norton

Identifying solar active regions (ARs), which consist of one or more pairs of magnetic patches with opposite polarities, is essential due to their significant role in dynamic solar atmospheric phenomena. In this study, we analyze ARs during…

Solar and Stellar Astrophysics · Physics 2025-09-16 Zahra Tajik , Hasan Rezaei , Mehdi Simiari , Hossien Safari

We describe a new tool developed for solar flare forecasting on the base of some sunspot group properties. Assuming that the flare frequency follows the Poisson statistics, this tool uses a database containing the morphological…

Solar and Stellar Astrophysics · Physics 2019-05-16 M. Falco , P. Costa , P. Romano

Recent studies indicate that a small number of rogue solar active regions (ARs) may have a significant impact on the end-of-cycle polar field and the long-term behavior of solar activity. The impact of individual ARs can be qualified based…

Solar and Stellar Astrophysics · Physics 2024-05-13 Ruihui Wang , Jie Jiang , Yukun Luo

Proper motions in a sunspot group with a delta-configuration and close to the solar disc center have been studied by employing local correlation tracking techniques. The analysis is based on more than one hour time series of G-band images.…

The increased amount of information provided by ongoing missions such as the Solar Dynamics Observatory (SDO) represents a great challenge for the understanding of basic questions such as the internal structure of sunspots and how they…

Solar and Stellar Astrophysics · Physics 2013-10-29 R. Gafeira , C. C. Fonte , M. A. Pais , J. Fernandes

Sunspot groups and bipolar magnetic regions (BMRs) serve as an observational diagnostic of the solar cycle. We use Debrecen Photohelographic Data (DPD) from 1974-2014 that determined sunspot tilt angles from daily white light observations,…

Solar and Stellar Astrophysics · Physics 2015-06-23 Bruce H. McClintock , Aimee A. Norton , Jing Li
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