Summary of NASA LWS TR&T
Focus Team:
“Predict Emergence of Solar Active
Regions Before they are Visible”
• Goals and measures of success: The goal of this
Focused Science Topic is to develop, test, and refine
techniques for the detection of active regions before they
are visible, the exploration of techniques to determine
whether preemergent or newly emerged active regions will
grow and become flare-productive, and to explore how
such knowledge could be incorporated into downstream
predictive models of the outer corona and heliosphere.
The prime measure of success for this work will be to
demonstrate a statistically significant ability to predict
the location of new active regions before they are visible
on the surface of the Sun and also their evolution.
The Team = everyone funded under this
focus topic
• MSU: PI Stein, Nordlund, Georgobiani,
Schaffenberger, Benson
• Stanford: Science PI Kosovichev, Scherrer, Zhao
• CoRA Near-side team: PI Birch, Braun, Leka,
Barnes, Crouch, Werne, & Lindsey
• CoRA Far-side team: PI Lindsey
• NSO: PI Hill, Gonzalez-Hernandez, Komm,
Burtseva
Summary of Yesterday’s Meeting
Irene: Calibrating Far-Side images
Rudi: Vertical flows in emerging active regions
Olga: Time-distance of an emerging active region
KD: Target selection, preparing data sets to test prediction methods
Graham: Discriminant analysis (Statistical
Bob: Progress on simulations
Junwei: Time-distance far-side imaging. Time-distance emerging AR.
Sasha: “Compare inversions results, not travel-times”
Charlie: Plans & motivation for modeling the interaction of waves
with a magnetic flux tube
Doug: estimate of travel-time shift from a rising flux tube
rising flux tube properties (Slide from Doug)
thin flux tube calculations (Fan & Gong 2000)
time
two days before emergence:
•depth z ~ 60 Mm
•speed vr ~ 150 m/s
•let diameter ~ fz (f ≤ 1 !)
•travel-time perturbation
 
fzvr
 f 1s
2
c0
•rms of single corr. ≥10 s
va
•can get N~100 correlations (maybe);
error of mean ≥ 1s
vr (rise speed)
•direct detection of vr (probably)
unlikely, but…?
We can use your help:
If you have an idea for detecting active regions …
Web Site:
http://www.cora.nwra.com/LWSPredictEmergence
Presentations from yesterday will appear there soon