Viewing archive of Thursday, 12 April 2001
Geophysical report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Solar and Geophysical Activity Summary 2001 Apr 12 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 102 Issued at 0245Z on 12 Apr 2001 This report is compiled from data received at SWO on 11 AprA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0024 0031 0035 M1.0 52 1256 1326 1349 9415 S22W27 M2.3 1f 3100 540 II/IV
B. Proton Events
The greater than 10 MeV proton event that began
at 0850 UTC on 10 April continues in progress. The peak flux so far
is 355 PFU at 2055 UTC on 11 April. The day end flux value was 113
PFU.
C. Geomagnetic Activity Summary
The geomagnetic field ranged from
quiet to severe storm levels, with a maximum estimated Kp-index of
8. A sudden storm commencement was observed at 1343Z on 11 April.
D. Stratwarm
None.
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 160 SSN 178 Afr/Ap 050/060 X-ray Background B7.9 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 3.6e+08 GT 10 MeV 1.2e+07 p/(cm2-ster-day) (GOES-8 satellite synchronous orbit W75 degrees) Daily Electron Fluence GT 2 MeV 1.30e+08 e/(cm2-ster-day) (GOES-8 satellite synchronous orbit W75 degrees) 3 Hour K-indices Boulder 3 3 3 2 3 8 5 6 Planetary 3 3 3 2 4 8 6 7
F. Comments
The greater than 2 MeV electron fluxes at Geosynchronous orbit attained high levels during the past 24 hours.
All times in UTC
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