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Title: PATHWAYS OF LARGE-SCALE MAGNETIC COUPLINGS BETWEEN SOLAR CORONAL EVENTS

Abstract

The high-cadence, comprehensive view of the solar corona by SDO/AIA shows many events that are widely separated in space while occurring close together in time. In some cases, sets of coronal events are evidently causally related, while in many other instances indirect evidence can be found. We present case studies to highlight a variety of coupling processes involved in coronal events. We find that physical linkages between events do occur, but concur with earlier studies that these couplings appear to be crucial to understanding the initiation of major eruptive or explosive phenomena relatively infrequently. We note that the post-eruption reconfiguration timescale of the large-scale corona, estimated from the extreme-ultraviolet afterglow, is on average longer than the mean time between coronal mass ejections (CMEs), so that many CMEs originate from a corona that is still adjusting from a previous event. We argue that the coronal field is intrinsically global: current systems build up over days to months, the relaxation after eruptions continues over many hours, and evolving connections easily span much of a hemisphere. This needs to be reflected in our modeling of the connections from the solar surface into the heliosphere to properly model the solar wind, its perturbations, andmore » the generation and propagation of solar energetic particles. However, the large-scale field cannot be constructed reliably by currently available observational resources. We assess the potential of high-quality observations from beyond Earth's perspective and advanced global modeling to understand the couplings between coronal events in the context of CMEs and solar energetic particle events.« less

Authors:
; ;  [1];  [2]
  1. Lockheed Martin Advanced Technology Center, 3251 Hanover Street, Palo Alto, CA 94304 (United States)
  2. Department of Mathematical Sciences, Durham University, Science Laboratories, South Road, Durham DH1 3LE (United Kingdom)
Publication Date:
OSTI Identifier:
22131035
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 773; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AFTERGLOW; DISTURBANCES; EXTREME ULTRAVIOLET RADIATION; HELIOSPHERE; MAGNETIC FIELDS; RELAXATION; SIMULATION; SOLAR CORONA; SOLAR WIND

Citation Formats

Schrijver, Carolus J., Title, Alan M., DeRosa, Marc L., and Yeates, Anthony R. PATHWAYS OF LARGE-SCALE MAGNETIC COUPLINGS BETWEEN SOLAR CORONAL EVENTS. United States: N. p., 2013. Web. doi:10.1088/0004-637X/773/2/93.
Schrijver, Carolus J., Title, Alan M., DeRosa, Marc L., & Yeates, Anthony R. PATHWAYS OF LARGE-SCALE MAGNETIC COUPLINGS BETWEEN SOLAR CORONAL EVENTS. United States. doi:10.1088/0004-637X/773/2/93.
Schrijver, Carolus J., Title, Alan M., DeRosa, Marc L., and Yeates, Anthony R. Tue . "PATHWAYS OF LARGE-SCALE MAGNETIC COUPLINGS BETWEEN SOLAR CORONAL EVENTS". United States. doi:10.1088/0004-637X/773/2/93.
@article{osti_22131035,
title = {PATHWAYS OF LARGE-SCALE MAGNETIC COUPLINGS BETWEEN SOLAR CORONAL EVENTS},
author = {Schrijver, Carolus J. and Title, Alan M. and DeRosa, Marc L. and Yeates, Anthony R.},
abstractNote = {The high-cadence, comprehensive view of the solar corona by SDO/AIA shows many events that are widely separated in space while occurring close together in time. In some cases, sets of coronal events are evidently causally related, while in many other instances indirect evidence can be found. We present case studies to highlight a variety of coupling processes involved in coronal events. We find that physical linkages between events do occur, but concur with earlier studies that these couplings appear to be crucial to understanding the initiation of major eruptive or explosive phenomena relatively infrequently. We note that the post-eruption reconfiguration timescale of the large-scale corona, estimated from the extreme-ultraviolet afterglow, is on average longer than the mean time between coronal mass ejections (CMEs), so that many CMEs originate from a corona that is still adjusting from a previous event. We argue that the coronal field is intrinsically global: current systems build up over days to months, the relaxation after eruptions continues over many hours, and evolving connections easily span much of a hemisphere. This needs to be reflected in our modeling of the connections from the solar surface into the heliosphere to properly model the solar wind, its perturbations, and the generation and propagation of solar energetic particles. However, the large-scale field cannot be constructed reliably by currently available observational resources. We assess the potential of high-quality observations from beyond Earth's perspective and advanced global modeling to understand the couplings between coronal events in the context of CMEs and solar energetic particle events.},
doi = {10.1088/0004-637X/773/2/93},
journal = {Astrophysical Journal},
number = 2,
volume = 773,
place = {United States},
year = {Tue Aug 20 00:00:00 EDT 2013},
month = {Tue Aug 20 00:00:00 EDT 2013}
}
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