Technical description of solution bkg00003.eops

1.  Purpose of solution:  Session EOP

2 - Analysis Center:  Federal Agency for Cartography and Geodesy (BKG Leipzig) and
                      Geodetic Institute of the University of Bonn

3.  Short narrative description of solution:

All available Mark III/IV sessions were analysed for this solution except one
baseline and small network sessions which are not suitable for reliable EOP 
determination. Celestial reference frame was fixed to ICRF-Ext1. Terrestrial
reference frame ITRF2000 with the associated velocity field is used for station
coordinates, reference epoche is 1997.0.

4.  Estimated parameters:

    a. celestial frame:  No

    b. terrestrial frame:  No

    c. Earth orientation:  X, Xdot, Y, Ydot, UT1-UTC, UT1dot, dPsi, dEps

    d. zenith troposphere:  1h piece-wise linear functions,
                            rate constraint generally 50 ps/hour

    e. troposphere gradient:  east and north offset,
			      offset constraint 0.5 mm,
			      rate constraint 0.5 mm/day

    f. station clocks:  1h piece-wise linear functions,
                        rate constraint generally 5.E-14

    g. baseline clocks:  set in initial analysis - usually used

    h. other:  No

5.  Celestial reference frame:

    a. a priori source positions:  ICRF-Ext.1

    b. source positions adjusted in solution:  No


6 - Terrestrial reference frame:

    a. a priori station positions:  ITRF2000                   

    b. a priori station velocities:  ITRF2000 

    c. reference epoch:  1997.0


7.  Earth orientation:

    a. a priori precession model:  IERS 1996

    b. a priori nutation model:  IERS 1996

    c. Short-period tidal variations in x, y, UT1:
    
       Model used according to:
       John Gipson, VLBI determination of neglected tidal terms in
       high frequency Earth Orientation Variation.
       Journal of Geophysical Research, Vol. 101, No. B12, p. 28051-28064
       Dec 10, 1996

    d. EOP estimation: X, Xdot, Y, Ydot, UT1-UTC, UT1dot, dPsi, dEps each session

8.  A priori geophysical models:

    a. troposphere: hydrostatic component with NMF mapping function

    b. solid Earth tide:  IERS Conventions

    c. ocean loading:  IERS Conventions

    d. atmosphere loading:  none

9.  Data type:  Group delays

10. Data editing: 
    Editing of outliers during adjustment when necessary.

11. Data weighting:  Observations are weighted using std reported
    in observational files; re-weighting iteration for each session
    to achieve the chi-square unity.

12. Standard errors reported:  Reported formal errors are derived from
    least-squares estimation propagated from data uncertainties and 
    weighted as discussed in #11.

13  Software:  Calc 9.12, SOLVE release: 2001.12.21

14. Other information:
    Field 18 contains the session code
    Field 19 contains the duration of experiments