J/ApJ/845/36 Complex network for solar active regions (Daei+, 2017)
Complex network for solar active regions.
Daei F., Safari H., Dadashi N.
<Astrophys. J., 845, 36 (2017)>
=2017ApJ...845...36D 2017ApJ...845...36D
ADC_Keywords: Sun ; Stars, flare
Keywords: Sun: activity ; Sun: flares
Abstract:
In this paper we developed a complex network of solar active regions
(ARs) to study various local and global properties of the network. The
values of the Hurst exponent (0.8-0.9) were evaluated by both the
detrended fluctuation analysis and the rescaled range analysis applied
on the time series of the AR numbers. The findings suggest that ARs
can be considered as a system of self-organized criticality (SOC). We
constructed a growing network based on locations, occurrence times,
and the lifetimes of 4227 ARs recorded from 1999 January 1 to 2017
April 14. The behavior of the clustering coefficient shows that the AR
network is not a random network. The logarithmic behavior of the
length scale has the characteristics of a so-called small-world
network. It is found that the probability distribution of the node
degrees for undirected networks follows the power law with exponents
of about 3.7-4.2. This indicates the scale-free nature of the AR
network. The scale-free and small-world properties of the AR network
confirm that the system of ARs forms a system of SOC. Our results show
that the occurrence probability of flares (classified by GOES class
C>5, M, and X flares) in the position of the AR network hubs takes
values greater than that obtained for other nodes.
Description:
The solar monitor (www.solarmonitor.org) records the solar data
observed by several solar space observatories and missions (e.g.,
GOES, GONG, ACE, STEREO, SDO, etc.).
4227 solar active regions (ARs) during 1999 January 1 to 2017 April 14
used for building the AR network are listed in table 1. See section 2
for further details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 24 36362 Solar active regions data (4227 unique ARs)
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See also:
J/ApJS/91/461 : EUV spectrum of solar active region (Thomas+, 1994)
J/A+A/304/563 : Cool X-ray flares of Sun with GOES (Phillips+, 1995)
J/ApJ/543/1016 : EUV spectrum of AR from SERTS-97 (Brosius+ 2000)
J/ApJ/721/901 : Solar quiescent filament channels (Su+, 2010)
J/ApJ/757/94 : Solar flares observed with GOES and AIA (Aschwanden, 2012)
J/ApJ/759/69 : Solar electron events (1995-2005) with WIND/3DP (Wang+, 2012)
J/ApJ/759/141 : Emission measures in solar active regions (Warren+, 2012)
J/ApJ/774/L27 : Solar flares predictors (Yang+, 2013)
J/A+A/555/A123 : 3D-MHD model of a solar active region corona (Bourdin+, 2013)
J/ApJ/786/19 : Statistical analysis of solar active regions (Barnes+, 2014)
J/A+A/574/A37 : Movies of 2012-10-16 solar flare (Dalmasse+, 2015)
J/ApJ/831/105 : Global energetics of solar flares. IV. CME (Aschwanden, 2016)
http://www.solarmonitor.org/ : Solar Monitor home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Region [8419/12650] National Oceanic and Atmospheric
Administration (NOAA) number
7- 16 A10 "Y/M/D" Date Date of the observation
18- 20 I3 deg Lat [-89/66] Heliographic latitude
22- 24 I3 deg Lon [0/359] Heliographic longitude
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Mar-2018