LOCATING FLARES WITH
SDO-EVE-ESP
Andrew Jones and the EVE team
EVE Space Weather Workshop October 6-8th. 2010
EUV SPECTROPHOTOMETER
ESP
EUV Detectors
Gold Grating
zero-Order
Ti Filter
Quadrant Detector
2
Al Filter
Aperture
ESP ZERO-ORDER
CHANNEL
Filter Photometer 0.1 – 7nm
Matches EVE - SAM, XPS diode channel
Quadrant diode
Hi cadence (¼ second)
Available with very low latency (L0CS)
3
FLARE LOCATION
Aperture
Sun Brightness = 1
Q1
Q2
Q3
Q4
X = [Q2 + Q4]-[Q1 + Q3]/sum = [(¼)+(¼)]-[(¼)+(¼)]/(1) = 0.00
Y = [Q1 + Q2]-[Q3 + Q4]/sum = [(¼)+(¼)]-[(¼)+(¼)]/(1) = 0.00
FLARE LOCATION
Aperture
Sun Brightness = 1
Flare brightness = 10
Q1
Q2
Q3
Q4
X = [Q2 + Q4]-[Q1 + Q3]/sum = [(¼+4)+(¼+1)]-[(¼+4)+(¼+1)]/(1+10) = 0.00
Y = [Q1 + Q2]-[Q3 + Q4]/sum = [(¼+4)+(¼+4)]-[(¼+1)+(¼+1)]/(1+10) = 0.55
MEASURED POSITIONS
SAM
ESP
6
EIT
CENTER OF IRRADIANCE
Measure the whole disk
Position reflects the COI
OK with Isolated Flares
Need to subtract pre-flare COI for better
accuracy with more active Sun
7
FIELD OF VIEW MAPS
EVE FOV maps every 3 months
Calibrate the quadrant diode response:
ESP X, Y vs. S/C α, β
OR... Have continuous calibration from SAM
Or AIA
8
FOV MAP ANALYSIS
Automatically
calculate slopes
from S/C position
data and ESP
response
Different slopes as
ESP aperture is
not symmetrical
9
FLARE LOCATIONS
!"#$%&'()*'+&'$,-.'&$/*0$#(123(41$
%#
&#
'#
(#
N
"#
ESP Zero-Order (0.1 - 7 nm)
1.00
E
$#
!"#
$#
N
E C W
S
S
mW/m2
!"#
0.10
0.01
Jan 01
Mar 01
May 01
Jul 01
Date 2010
Sep 01
10
Oct 31
Dec 31
W
"#
CURRENT ESP COI ON EVE
Quick Look PAGE
http://lasp.colorado.edu/eve/data_access/quicklook/quicklook_data/L0CS/latest_pointing.png
CORRELATION
#$>%/+0%!"#$(&'$%@A/.3%B*8C/.1D*+%
-)#2+5%
!"#$%&%'()*+*%#$,-).+(%
/0%&%+).'1''%
!
!"#$%&'$()*+,%-../01/+23%456(457+8%9:;8<=%%
-)#2+4%
-)#2+*%
-)#2+1%
-)#2+3%
-)#2+4%
-)#2+5%
-)#2+'%
#$>%4(".03.%-../01/+23%456(?%+8%9:;8<=%%
12
PREDICTION CHART
XRS Flare Magnitude Prediction!
XRS Irradiance!
A-Class!
B-Class!
C-Class!
M-Class!
Prediction!
Predicted XRS Maximum Irradiance (W/m2)!
1.E-04!
1.E-05!
1.E-06!
1.E-07!
1.E-08!
1.E-06!
1.E-05!
1.E-04!
1.E-03!
Initial Risetime (W m-2 h-1)!
13
1.E-02!
1.E-01!
CONCLUSIONS
Flare magnitude and location provide vital
clues to the effects likely to be experienced at
Earth
ESP can provide very fast flare location
Positions calculated from FOV Maps and SAM
are essentially identical
This is a pathfinder for GOES-R EXIS XRS
We have started to look at flare prediction
14