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Data format for the VIRGO_V2_51.PLT

  COL   FMT    DESCRIPTION
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 1- 4   I4     Year
 5- 6   I2     Month
 7- 8   I2     Day
 9-10   2X     Blank
11-18   F8.3   Total Solar Irradiance (TSI)

CREATED: Nov 19 1999
VERSION: 2.51
NOTE:    Versions higher than 1.2 show also VIRGO irradiance data after the 
         vacation of SOHO in summer 1998. Note that 
         the values after June 25 1998 are still preliminary.
         These data are also corrected for a trend
         -0.090 ppm/day determined 
         by comparison with ACRIM II (see ref.3).
         More detailled information about the individual measurements 
         of the VIRGO radiometers can be found on the VIRGO homepage
         http://virgo.so.estec.esa.nl/ and in the references below.
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Total Solar Irradiance results from VIRGO (Variablity of solar IRradiance and
Gravity Oscillations) onboard SOHO (SOlar and Heliospheric Observatory).
REFERENCES: (these papers can also be found at the anonymous ftp server 
obsun.pmodwrc.ch/pub/publications/ as re- or preprints
(1) Fr{\"o}hlich, C., Crommelynck, D., Wehrli, C., Anklin, M., Dewitte, S., Fichot,
  A., Finsterle, W., Jim{\e}nez, A., Chevalier, A. and Roth, H.~J.: 1997,
  In-flight performances of {VIRGO} solar irradiance instruments on {SOHO},
  {\em Sol. Phys.} {\bf 175},~267--286.
(2) Anklin, M., Fr{\"o}hlich, C., Finsterle, W., Crommelynck, D.~A. and Dewitte,
  S.: 1998, Assessment of degradation of {VIRGO} radiometers onboard {SOHO},
  {\em Metrologia} {\bf 35}, p.686-688, 1999.
(3) Fr{\"o}hlich, C.,  Anklin, M., Accuracy and Precision of Total Solar Irradiance:
  An Assessment of the last 20 years of Space Radiometry, {\em Metrologia}, 
  in press, 2000