Technical description of solution XXXXnnnn

1.  Purpose of solution: e.g., session EOP

2.  Analysis center: e.g., GSFC (XXXX, exactly 4 characters)
    Solution code: e.g. 1120 (nnnn, exactly 4 characters)

3.  Short narrative description of solution:

4.  Estimated parameters:

    a. celestial frame: e.g., right ascension, declination

    b. terrestrial frame: e.g., X0, Y0, Z0, Xdot, Ydot, Zdot

    c. Earth orientation: e.g., x, y, UT1-TAI, UT1dot, dpsi, deps

    d. zenith troposphere: e.g., continuous piecewise linear, 20 min interval

    e. troposphere gradient: e.g., east and north offset and rate
    
    f. station clocks: e.g., continuous piecewise linear with 1 hr interval

    g. baseline clocks: e.g., usually

    h. other: e.g., global antenna axis offsets 

5.  Celestial reference frame:                

    a. a priori source positions: e.g., ICRF

    b. source positions adjusted in solution: yes/no

    If yes,

    c. definition of orientation: e.g., no-net-rotation tie to the
       ICRF using only the ICRF defining sources.

    d. source position estimation: e.g., all sources estimated globally

    If no,

    e. solution identification or reference:

6 - Terrestrial reference frame:

    a. a priori station positions: e.g., ITRF96

    b. a priori station velocities:, e.g., NUVEL1A-NNR

    c. reference epoch:

    d. station positions/velocities adjusted in solution: yes/no

    If yes,

    e. definition of origin, orientation, and their time evolution: e.g.,
       Evolution of the TRF is set by no-net-translation, no-net-rotation,
       no-net-translation-rate and no-net-rotation-rate conditions on the
       horizontal position and velocity adjustments of the following stations :

       ALGOPARK BR-VLBA   DSS45     FD-VLBA  FORTLEZA  GILCREEK  HARTRAO  
       ...

    f. station parameter estimation: e.g., for most stations 
       X0, Y0, Z0, Xdot, Ydot, Zdot

    g. stations with constraints: e.g., 

       The stations with insufficient data or time interval are constrained 
       to move with NNR-NUVEL1A with uncertainties in vertical, east and
       north rates of 0, 3, and 3 mm/yr, respectively.  These stations are:

       AUSTINTX  AZORES    BERMUDA   BLOOMIND  BREST     
       ...

       Velocities of the following groups of sites are constrained to be identical:

       DSS65     ROBLED32
       ...

    h. stations with discontinuous positions and date of discontinuity: e.g.,

       YAKATAGA 871201
       ...

    i. stations with nonlinear velocities: e.g.,

       The position of HRAS 085 is estimated as a piecewise-linear, continuous
       function with 2-month segments.

    j. relativity scale: e.g.,
       LE    : local Earth in agreement with TCG (IUGG Resolution)

    k. permanent tide correction: yes/no

       "Yes" means that both the permanent and the periodic tides  have been
       modeled, so that the output station position is for after the removal
       of both the permanent and the periodic tidal effect.

    If no,

    l. solution identification or reference:

7.  Earth orientation: 

    a. a priori precession model: e.g., IAU(1976)

    b. a priori nutation model: e.g., IAU(1980)

    c. a priori short-period tidal variations in x, y, UT1: e.g., 

       UT1 tidal terms  (microseconds)
       
        l  l' F  D Om  GST |   Cos  |   Sin   |
                       +pi |        |         |
       -----------------------------------------
        2  0  2  0  2 -1      -.13     -1.24
        ...
       -----------------------------------------
       
       Polar motion tidal terms  (microarcseconds)
       
        l  l' F  D Om  GST |   Cos  |   Sin   |
                       +pi |        |         |
       -----------------------------------------
       -2  0 -2  0 -2  1     -6.90      5.52
        ...
       -----------------------------------------

    d. EOP estimation: e.g., x, y, UT1, UT1dot, deps, dpsi each day

8.  A priori geophysical models:

    a. troposphere: e.g., NMF mapping function

    b. solid Earth tide: e.g., IERS Conventions

    c. ocean loading: e.g., none

    d. atmosphere loading: e.g., from VLBI data and weather model

9.  Data type: e.g., delays

10. Data editing: e.g., 7 deg elevation cutoff

11. Data weighting: e.g., reweighting by site for each session

12. Standard errors reported: e.g., all errors are derived solely from
    data uncertainties and noise RSSed for each site for each session
    to make the chisquare of individual session solutions unity.

13  Software: e.g., CALC 8.2, SOLVE 5.0129

14. Other information: e.g., URL for long tables