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January 18, 2011
                       DAILY SOLAR INDICES SUMMARIES

 			  
This directory contains three daily summaries of solar indices. The ascii
files are formatted in tables. The tables and column headings are defined
below.

                          Update Schedule
   Daily Particle Data:     by 0230 UTC
   Daily Solar Data:        by 0230, 0830, 1430, and 2030 UTC
   Daily Geomagnetic Data:  every three hours beginning at 0030 UTC


SWPC data are preliminary and some are later adjusted or corrected. Solar 
and Geomagnetic indices are especially subject to adjustment. Final data
are archived at the National Geophysical Data Center.
http://www.ngdc.noaa.gov/stp

The SWPC Primary GOES satellite for the Electron Fluence was changed from
GOES 12 to GOES 11 on December 1, 2008.
 
SWPC keeps older preliminary data online from 1996 for customers who want
this data. See /ftp/pub/warehouse or
http://www.swpc.noaa.gov/ftpmenu/warehouse.html


Your comments and suggestions are welcome. 
 swpc.webmaster@noaa.gov

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A. DAILY SOLAR DATA

Radio Flux Penticton 10.7 cm: The 10.7 cm (2800 MHz) full Sun radio flux 
reported by the Dominion Radio Astrophysical Observatory at Penticton, B.C., 
Canada on the date indicated.  Measurements are made at approximately 2000UT. 
Values are in units of 10 E-22/Sq Wm/Hz and are not corrected for the variable 
Sun-Earth distance resulting from the eccentric orbit of the Earth around the 
Sun.

Sunspot No: The SESC sunspot number for the indicated date is from the daily 
Solar Region Summary issued by SESC. The SESC sunspot number is computed 
according to the Wolf Sunspot Number R=k (10g+s), where g is the number of 
sunspot groups (regions), s is the total number of individual spots in all 
the groups, and k is a variable scaling factor (usually <1) that indicates 
the combined effects of observing conditions, telescope, and bias of the 
solar observers.  A sunspot number of zero indicates there were no visible 
sunspots on that date; a * indicates that no observations were taken. The   
sunspot region information used to compute the daily sunspot number 
incorporates reports from as many as six observatories.  These reports 
are used to form a composite picture of each individual region, including 
sunspot number, area and classification, taking into account such factors as  
the time of observation and the quality of seeing.  This composite 
information is the daily average obtained from the reporting observatories 
and may not represent the latest data. It is reported daily in the Solar 
Region Summary and listed in the Region Summary section of the Weekly.

Sunspot Area : Sum of the corrected area of all observed sunspots, in units of 
millionths of the solar hemisphere.

X-ray Background Flux : The daily average background x-ray flux as measured on 
the SWPC primary GOES satellite. Note: X-ray flux values below the B1 level can 
be erroneous. Energetic electron contamination of the x-ray sensors occurs. At 
times of high electron flux at geosynchronous altitude, the x-ray measurements
in the low A-class range can be in error by 20-30%. Measurements taken during
periods of low energetic electron fluxes are much more accurate.
   Daily GOES X-ray Background Flux algorithm:
     o The 24 one-hour X-ray 1-8 Angstrom; values are divided into three 
       8-hour sections
     o The minimum for each of these three 8-hour sections is determined;
         ... call them min1, min2, and min3
     o The average of the minima from the first and last 8-hour sections 
        is calculated: min_avg = 1/2 (min1 + min3)
     o Daily Background X-Ray Flux is the smallest of min2 or min_avg
      X-Ray_background = minimum of (min2 or min_avg)</li>
            
Flares : The total number of optical and x-ray flares observed during the day.

Missing data is shown as -1, except X-ray Background Flux is shown as *.


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B. DAILY PARTICLE DATA

Proton Fluence: The daily integrated particle fluxes measured by the primary 
GOES spacecraft at geosynchronous altitudes for protons of energies
>1 MeV, >10 MeV, and >100 MeV in units of Protons/sq cm/day/sr.

Electron Fluence: The daily integrated electron fluxes measured at 
geosynchronous altitudes, by the primary GOES spacecraft for electrons, of 
energies > 2 MeV in units of Electrons/sq cm/day/sr. 

Neutron Monitor Percent of Background.
                                      
Missing proton and election values are shown as -1.0e+05.
Missing Neutron monitor data are shown as -1.00.

For primary GOES designations see http://www.swpc.noaa.gov/Data/goes.html


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C. DAILY GEOMAGNETIC DATA

Fredericksburg, College, and Estimated Planetary A and K Indices:  
The daily 24-hour A index and eight 3-hourly K indices from the 
Fredericksburg (middle-latitude) and College  (high-latitude) stations  
monitoring Earth's magnetic field. The estimated planetary 24 hour 
A index and eight 3-hourly K indices are derived in real time from a 
network of western hemisphere ground-based magnetometers.  These indices 
may differ from the final Ap values derived by the Institut fur
Geophysik, Gottingen, Germany, using a global network of magnetometers. 
K indices range from 0 (very quiet) to 9 (extremely disturbed).  A indices 
range from 0 (very quiet) to 400 (extremely disturbed). An A index of 30 or  
greater indicates local geomagnetic storm conditions. See Appendix 
B for further explanation.

Missing A- and K-indices are shown as -1.