Observational characteristics
of AR 12192
Xin Huang, Huaning Wang
National Astronomical Observatories,
Chinese Academy of Sciences

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Main Contents• BackgroundWhy we analyze AR 12192• Event Analysis
What are the differences between AR 12192
and other active regions with confined flares• Forecasting Can we forecast this event• Conclusions
 What can we learn from this event &What can we do in the future work
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Background• Preliminary Analysis of Latest Events
Selected events for detailed analysis
Large active region without CMEs: Activities ofNOAA/AR12192
”NOAA/AR12192 had area larger than that of AR10486 at
the moment of the Halloween event in October, 2003 andproduced many M-class and X-class flares. However, solar
energetic particle events and geomagnetic storms were notproduced by activity of AR12192.”• AR12192 is the largest sunspot group in 24 years. It produces 6
GOES X-class flares (Sun et al 2015)• We have developed a solar events forecasting model
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Space Weather Event Report @AOSWA3Event Analysis• Confined flare or eruptive flare(Wang & Zhang 2007 ApJ)

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Rise time <13minute
Decay time >9 minute4

Event Analysis• Confined flare or erupted flare(Cheng et al 2011 ApJ)AR 10720

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Event Analysis• Confined flare or erupted flare(Cheng et al 2011 ApJ)

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Event Analysis• AR 12192• X 16 Flare :2014.10.22 14:02(begin)
14:50(end) 14:28(maximum) S14E13

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Event Analysis• AR 12192• Nonlinear force-free coronal magnetic field extrapolation basedon the direct boundary integral formulation(He &Wang 2008 JGR)

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Event Analysis• AR 12192• Decay index at height of 10 Mm: 0.4
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Distance (Mm)

5040302010

Cheng et al 2011 ApJ00

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150
100
Rise Time (Minutes)

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Forecasting• Predictors••••

Length of Neutral Line
Summation of photospheric magnetic free energy density
Decay Index at the height of 10 Mm
Transverse magnetic flux ratio between the summation from0Mm to 10Mm and the summation from 10Mm to 20Mm
• Distance between the center of longitudinal magnetogram
and the center of photospheric magnetic free energy density(Dmf)• Distance Ratio between Dmf and Dpn (Dpn is the distance
between positive magnetic field and negative magnetic field)

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10Forecasting• Modela b c <-- classified as
25 4 2 | a = 080%
4 20 7 | b = 164%
1 6 24 | c = 277%
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11Forecasting• Test for AR12192

a b c <-- classified as000|a=0010|b=1000|c=2

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Summary• AR12192 is similar with other active region with confinedflares• Nonpotential parameters are used to forecast weather or not
solar flare happens• The potential location of solar flare& the overlying coronal magnetic field
are important to determine it is confined oreruptive flare• AR 12192 remind us we need consider solar flares andCMEs together• The forecasting capability remains probabilistic
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Thanks！

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