Viewing archive of Monday, 20 September 2004
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.
:Product: 20040920SGAS.txt
:Issued: 2004 Sep 20 0250 UT
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.comJoint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 264 Issued at 0245Z on 20 Sep 2004 This report is compiled from data received at SWO on 19 SepA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 1646 1712 1739 0672 M1.9 130 520 II/IV
B. Proton Events
A greater than 10 MeV proton event followed
today's M1 flare at 19/1712Z. The proton event began at 19/1925Z and
was still in progress at the time of issue. The maximum flux value
so far is 47 pfu at 19/2335Z. A greater than 100 MeV proton flux
enhancement was also observed, but has not exceeded the 1 pfu event
threshold.
C. Geomagnetic Activity Summary
The geomagnetic field was quiet to
unsettled. Solar wind speed was generally below 400 km/s.
D. Stratwarm
None
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 105 SSN 042 Afr/Ap 004/005 X-ray Background B1.4 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 1.6e+06 GT 10 MeV 6.0e+05 p/(cm2-ster-day) (GOES-11 satellite synchronous orbit W99 degrees) Daily Electron Fluence GT 2 MeV 2.00e+08 e/(cm2-ster-day) (GOES-12 satellite synchronous orbit W75 degrees) 3 Hour K-indices Boulder 1 0 1 1 1 1 1 3 Planetary 1 1 1 1 2 2 2 3
F. Comments
None
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