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Title: Active Longitude and Coronal Mass Ejection Occurrences

Abstract

The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. Wemore » concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.« less

Authors:
; ;  [1]; ;  [2]
  1. Solar Physics and Space Plasmas Research Centre (SP2RC), School of Mathematics and Statistics, University of Sheffield Hounsfield Road, Hicks Building, Sheffield S3 7RH (United Kingdom)
  2. Department of Physics, Indian Institute of Technology (Banaras Hindu University), Varanasi (India)
Publication Date:
OSTI Identifier:
22661259
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 838; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DISTRIBUTION; ERUPTION; HELICITY; MAGNETIC FIELDS; MASS; ROTATION; SIMULATION; SOLAR ATMOSPHERE; SOLAR FLARES; SUN; SUNSPOTS

Citation Formats

Gyenge, N., Kiss, T. S., Erdélyi, R., Singh, T., and Srivastava, A. K., E-mail: n.g.gyenge@sheffield.ac.uk. Active Longitude and Coronal Mass Ejection Occurrences. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA62A8.
Gyenge, N., Kiss, T. S., Erdélyi, R., Singh, T., & Srivastava, A. K., E-mail: n.g.gyenge@sheffield.ac.uk. Active Longitude and Coronal Mass Ejection Occurrences. United States. doi:10.3847/1538-4357/AA62A8.
Gyenge, N., Kiss, T. S., Erdélyi, R., Singh, T., and Srivastava, A. K., E-mail: n.g.gyenge@sheffield.ac.uk. Mon . "Active Longitude and Coronal Mass Ejection Occurrences". United States. doi:10.3847/1538-4357/AA62A8.
@article{osti_22661259,
title = {Active Longitude and Coronal Mass Ejection Occurrences},
author = {Gyenge, N. and Kiss, T. S. and Erdélyi, R. and Singh, T. and Srivastava, A. K., E-mail: n.g.gyenge@sheffield.ac.uk},
abstractNote = {The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. We concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.},
doi = {10.3847/1538-4357/AA62A8},
journal = {Astrophysical Journal},
number = 1,
volume = 838,
place = {United States},
year = {Mon Mar 20 00:00:00 EDT 2017},
month = {Mon Mar 20 00:00:00 EDT 2017}
}
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