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SH21B-2403 (12/15/2015, 8:00-12:20, Moscone South – Poster)
New Publicly Available tool for Simulating Coronal
Mass Ejections
Igor V. Sokolov1, Richard E. Mullinix2, Aleksandre Taktakishvili2,
Anna Chulaki2, Meng Jin3, Ward B. Manchester1, Bart van der
Holst1 and Tamas Gombosi1
1. CLaSP, University of Michigan, Ann Arbor MI
2. CCMC, Goddard Space Flight Center, Greenbelt MD
3. Lockheed Martin Solar and Astrophysics Lab, Palo Alto CA
Thanks to Maria M. Kuznetsova and Spiro Antiochos
Abstract
2
We present and demonstrate a new tool, EEGGL (Eruptive Event
Generator using Gibson-Low configuration) for simulating CMEs
Coronal Mass Ejections).
CMEs are among the most significant space weather events,
producing the radiation hazards (via the diffuse shock acceleration
of the Solar Energetic Particles – SEPs), the interplanetary shock
waves as well as the geomagnetic activity doe to the drastic
changes of the interplanetary magnetic field within the “magnetic
clouds” (“flux ropes”). Some of these effects may be efficiently
simulated using the “cone model”, which is employed in the real-
time simulations of the ongoing CMEs at the NASA-Goddard Space
Flight Center. The cone model provides a capability to predict the
location, time, width and shape of the hydrodynamic perturbation
in the upper solar corona (at ~0.1 AU), which can be used to drive
the heliospheric simulation (with the ENLIL code, for example). At
the same time the magnetic field orientation in this perturbation is
uncertain within the cone model, which limits the capability of the
geomagnetic activity forecast.
Abstract (continued)
3
The new EEGGL tool recently developed at the Goddard Space
Flight Center in collaboration with the University of Michigan
provides a new capability for both evaluating the magnetic field
configuration resulting from the CME and tracing the CME through
the solar corona. In this way not only the capability to simulate the
magnetic field evolution at 1 AU may be achieved, but the also the
more extensive comparison with the CME observations in the solar
corona may be achieved.
Based on the magnetogram and evaluation of the CME initial
location and speed, the user may choose the active region from
which the CME originates and then the EEGGL tools provides the
parameters of the Gibson-Low magnetic configuration to
parameterize the CME. The recommended parameters may be used
then to drive the CME propagation from the low solar corona to 1 AU
using the global code for simulating the solar corona and inner
heliosphere. The Community Coordinated Modeling Center (CCMC)
provides the capability for CME runs-on-request, to the heliophysics
community.
Demo for CME 2012-07-12
4
We demonstrate how the new tools are used to simulate a halo CME
2012-07-12 (https://kauai.ccmc.gsfc.nasa.gov/DONKI/view/CME/14/1)
StereoCAT is used to find CME Speed
5
StereoCAT (http://ccmc.gsfc.nasa.gov/analysis/stereo/) is developed at
the CCMC. By tracing the CME front, we find CME Speed=1300km/s.
StereoCAT finds CME Start time
6
CME start time = Snapshot Time – D/(CME speed) = 13:51
D
Snapshot time
StereoCAT guesses CME place of birth
7
Latitude is -20o. Estimates for (HEEQ) longitude are +/- 6o
8
The new tool, EEGGL (Eruptive Event Generator using Gibson-Low
configuration – see Splash page
http://ccmc.gsfc.nasa.gov/analysis/EEGGLInfo/EEGGL.html
and the tool itself: http://ccmc.gsfc.nasa.gov/analysis/EEGGL/) has
been recently developed at the CCMC (Goddard Space Flight
Center) in collaboration with the University of Michigan.
Based on the magnetogram and evaluation of the CME initial
location, speed, and start time the user may
choose the active region from which the CME originates;
then the EEGGL tools provides the parameters of the Gibson-Low
magnetic configuration to parameterize the CME;
the recommended parameters may be used then to drive the CME
propagation from the low solar corona to 1 AU using the global code
for simulating the solar corona and inner heliosphere. To achieve this,
the EEGGL has a link to the run submission web page, which helps
the user to fill in the request form for a simulation run.
Newly Developed EEGGL tool
EEGGL tool (historic events): chose AR
9
For a start time, 2012-07-12.13:51 calculate CR number 2125 and
Carrington longitude 83. Find AR in the synoptic magnetic map for
CR2125 near the point with longitude 83+/-6o and latitude -200
CME origin point as found from StereoCAT
Find Parameters for GL configuration
10
Choose and mark bipolar configuration of solar spots in this AR
1.Mark positive and negative spots
2.Click “Recommended parameters”
Fill in Form to Request Simulation Run
11
With the found parameters for GL configuration request a run.
1. Parameters are found
2. Request SWMF run
Submit Your Run and Wait
12
SWMF/AWS☼M Model
Radiative cooling
Radiative cooling
Heat conduction
Heat conduction
w+
w+
w−
w−
Heat conduction: Spitzer (r<5Rs) + Hollweg (r>5Rs)
Radiative cooling from CHIANTI
Wave pressure gradient accelerates and heats
Two (Ti, Te) or three (Ti||, Ti⟘, Te) temperatures
Turbulent energy transport along field lines:
±=2
L?rw⌥
⇢L?pB= 150 kmpT
R=min{Rimb ,max [±]}
8
>
>
<
>
>
:
⇣12qw
w+⌘w+4w
01
4w<w
+<4w
⇣2qw
w+1⌘w+1
4w
Sokolov&et&al.,&ApJ,&764,&23&(2013).&
van&der&Holst&et&al.,&ApJ,&782,&81&(2014).&
Rimb =s[(VA·r) log VA]2+B
B·(r⇥u)2
(Π/B)=1.1×106Wm−2T−1
Threaded Field Line Model
Recognize that between 1Rs and 1.15Rs u || B and u≪Vslow,VA,Vfast
Inner boundary of AWS☼M-R is at 1.15Rs
Each boundary cell center is connected to the upper chromosphere by a
magnetic field line
Quasi-steady-state mass, momentum and energy transport is solved
along the connecting field line (1D equations!)
The AWSoM-R model simulates Solar Corona (SC) on the AMR grid of
~3 million cells and Inner Heliosphere (IH) in on the AMR grid of about
35 million cells with an improved resolution within the region in which
the CME propagates.
The Gibson-Low configuration is superimposed with the
observationally constrained parameters, to simulate CME
The simulation on 120 CPUs on the CCMC cluster hilo takes 17 hours
for the state prior to eruption and then 16 hours to simulate 4-10 hours
of the CME evolution in the SC and then about 3 days of its evolution
in the IH.
Future Work
15
Acknowledgement
The collaboration between the CCMC and University of Michigan is
supported by the NSF SHINE grant 1257519 (PI Aleksandre
Taktakishvili)
The work performed at the University of Michigan was partially
supported by the National Science Foundation grant AGS-1322543.!
We would also like to acknowledge high-performance computing
support from Yellowstone (ark:/85065/d7wd3xhc)!provided by
NCAR's Computational and Information Systems Laboratory,
sponsored by the National Science!Foundation.
We will add a capability to simulate real-time CMEs based on
the existing automated real-time simulation system .