IVS EOP FORMAT Version 2.2
                    Axel Nothnagel, IVS Analysis Coordinator
			       nothnagel@uni-bonn.de
                              Last updated: 2010.07.23

File names ending with ".eops" normally contain nutation offsets in
dpsi, deps w.r.t. the IAU1980 nutation model while file names ending
with ".eoxy" contain nutation offsets in dX, dY in the new nutation 
paradigm and w.r.t. the IAU2000 model (the model should exclude free
core nutation).

Files are free format with fields separated by at least one blank.

 FIELD   CONTENTS
 
  1     Decimal MJD of the measurement as TAI time tag (with at least 5 decimal digits) 
 	
     EARTH ORIENTATION

  2     x of the pole (arcseconds)
  3     y of the pole (arcseconds)
  4     UT1-UTC (seconds)
  
     NUTATION

  5     dpsi or dX (milliarcseconds)
  6     deps or dY (milliarcseconds)
  
     UNCERTAINTY OF EARTH ORIENTATION AND NUTATION

  7     uncertainty in x (arcseconds)
  8     uncertainty in y (arcseconds)
  9     uncertainty in UT1-UTC (seconds)
 10     uncertainty in dpsi or dX (milliarcseconds)
 11     uncertainty in deps or dY (milliarcseconds)

 12     wrms residual delay of the session in ps (preferably integer)
 
    CORRELATIONS

 13     correlation coefficient : x, y
 14     correlation coefficient : x, UT1
 15     correlation coefficient : y, UT1
 16     correlation coefficient : dpsi,deps or dX/dY
   
    INDICATORS

 17	number of observables	 
 18     6 character session code according to the 2nd
	column of IVS master schedules,
	e.g for 2002: ftp://gemini.gsfc.nasa.gov/pub/master/master02.txt
 19 	span of the observation (in hours)	 
 
   RATES OF EARTH ORIENTATION AND NUTATION

 20	x rate of the pole (arcseconds/day)
 21	y rate of the pole (arcseconds/day)
 22	excess length of day (LOD) (seconds), see comment below 
 23	dpsi rate (milliarcseconds/day)
 24	deps rate (milliarcseconds/day)
 
   UNCERTAINTY OF RATES OF EARTH ORIENTATION AND NUTATION

 25     uncertainty in x rate (arcseconds/day)
 26     uncertainty in y rate (arcseconds/day)
 27     uncertainty in LOD (s)
 28     uncertainty in dpsi rate (milliarcseconds/day)
 29     uncertainty in deps rate (milliarcseconds/day)

   CONFIGURATION OF NETWORK EMPLOYED FOR THESE RESULTS

 30     sequence of two-character IVS station identifiers as maintained 
        in IVS master control file ns-codes.txt (no blanks between stations)
        e.g. TsWzWfTcGcFt45Oh, TsWzNy or NyTs
        N.B.: There may be several lines for an individual session
              identifying different station configurations 


Comments:

- For the EOP rates, days are in 86400 SI seconds.
- The lines starting with characters "! # or *" are considered as comments.
- Although it is inconsistent to have LOD in the group of rates due to the
  toggling of the sign, it is maintained here for consistency with other
  space techniques.
  LOD = UT1(n) - UT1(n+1) with n in days.
  LOD has the same magnitude but opposite sign of the UT1-UTC rate 
  or the UT1-TAI rate, which are normally determined in VLBI analyses and
  given in seconds/day.


Axel Nothnagel