Mopitt sci. meeting at IGARSS,Toronto, June-2002
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SA A seen by M opitt (2000 – 2002) F lorian Nichitiu, T oronto, Mopitt sci. meeting at IGARSS,Toronto, June-2002
description
Mopitt sci. meeting at IGARSS,Toronto, June-2002. “Duck” , “Box” and “Pond” Proton flux contour at 705 Km altitude. Non-SAA events : North/South asymmetry. Mopitt : number of SEU in Nov = 67 . 6 Nov and 24 Nov. : ACE detector saturated due to proton event -> Strong Shock - PowerPoint PPT Presentation
Transcript of Mopitt sci. meeting at IGARSS,Toronto, June-2002
SAA seen by Mopitt(2000 – 2002)
Florian Nichitiu, Toronto,
Mopitt sci. meeting at IGARSS,Toronto, June-2002
We report on indirect observations of Single EventUpsets occurring in the Mopitt accelerometer device.The strong localization of these events in the SouthAtlantic Anomaly (SAA) and polar (South) regionsleads to conclusion that these SEU are caused bynuclear reactions in the piezoelectric sensing element ofthe accelerometer.
We can note that the SAA events are :- Day-Night symmetric ( in frequency and location)-The non-SAA events are highly North/Southasymmetric(with an accumulation of events in the South polarregion).
Because of a long period of observations ( 1.5 year) wewere able to showthe correlation between monthly frequency ofaccelerometer SEU and thesolar activity ( monthly average sun spot number , bigsolar flare events).
0.1 0.2 0.3 0.4 0.5 0.60
100
200
300 0.17561 0.01837
0.1 0.2 0.3 0.4 0.5 0.6 0.715960.6
15960.7
SAA event
Comp. Vib. Z
Tim
e ( 2
001/
Sept
/12)
Acc Intensity
-100 -80 -60 -40 -20 0 20 40 60 80 100
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8A
cc In
ten
sity
Lat-200 -150 -100 -50 0 50 100 150 200
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Acc In
ten
sit
y
Long
-45 -40 -35 -30 -25 -20 -15 -10 -50
20
40
-45<La <0
Latitude
-25.94759 8.10636
-80 -70 -60 -50 -40 -30 -20 -10 00
20
40
-80<Long <0
Longitude
-47.07144 13.87743
“Duck” , “Box” and “Pond” Proton flux contour at 705 Km altitude
-200 -100 0 100 2000
10
20
30
Long. for South Pole Day=59 Night=36
(Lat <-55 )18.9377 100.62552
Non-SAA events : North/South asymmetry
-200 -100 0 100 2000
2
4
6
(Lat >55 )
Long for North Pole
0 5 10 15 20 25
15
20
25
30
35
Acc Events
Sun Spot Nr
Mopitt Anomaly
Nr
of
Acc
Eve
nts
/Mo
nth
Month ( March 2000 - Oct 2001 )
0 5 10 15 20 25
80
100
120
140
160
180
80 100 120 140 160 180
15
20
25
30
35
April 2000 - Oct 2001
Sun Spot Nr/Month
Nr
of
Acc
Eve
nts
/Mo
nth
16010 16020 16030 16040 16050
-200
-150
-100
-50
0
50
100
150
200
Strong solar proton events
SAA
6 Nov 2001
Lo
ng
Time ( November 2001)
Mopitt : number of SEU in Nov = 67 .6 Nov and 24 Nov. : ACE detector saturateddue to proton event -> Strong Shock http://www.ips.gov.au/asfc/data/sol/shock.txt
