Technical description of solution bkgint14 Intensives

 1.  Purpose of solution: Intensive EOP

 2.  Analysis center: Federal Agency for Cartography and Geodesy (BKG Leipzig)

 3.  Short narrative description of solution:

All available Intensive sessions since 1999 were analysed for 
this solution (including the TSUKUBA-WETTZELL experiments since 2002).
Celestial reference frame was fixed to ICRF2.         
Terrestrial reference frame VTRF2008a and the associated velocity field 
are used for station coordinates, reference epoche is 2000.0. Only clock 
parameters, tropospheric zenith parameters and UT1 were adjusted using
least squares technique. The UTC epoch is the middle epoch for each session.
The values of the official list of VLBI antenna axis offsets antenna-info.txt
based on gsfc_itrf2013.axo.txt were used.
Use of CALC11 includes the standards of IERS Conventions 2010.
Ocean loading model TPXO.7.2 omputed by H. G. Scherneck was applied (blokq.c11.dat).
Thermal expansion modelling developed by A. Nothnagel (2008) was used with  
antenna properties from antenna-info.txt.
The values of station eccentricities were taken from the official IVS-table ECCDAT.ecc.
The Vienna mapping function (VMF1) is applied for troposphere correction modelling 
in form of TRP files from GSFC.



 4.  Estimated parameters:

     a. Celestial frame: No

     b. Terrestrial frame: No

     c. Earth orientation: UT1-TAI 

     d. Zenith troposphere: Generally offsets for each station  

     e. Troposphere gradient: No
     
     f. Station clocks: quadratic local polynomial of clock function

     g. Baseline clocks: No 

     h. Other: No

 5.  Celestial reference frame:                

     a. A priori source positions: ICRF2                                  

     b. Source positions adjusted in solution: No

 6 - Terrestrial reference frame:
 
     a. a priori station positions:  VTRF2008a

     b. a priori station velocities:  VTRF2008a
                                      
     c. Reference epoch: 2000.0

 7.  Earth orientation: 

     a. a priori precession/nutation model: IAU2006/2000 Precession/Nutation 

     b. a priori short-period tidal variations in Xpol, Ypol and UT1 due to short
        period tidal were applied as recommended in the
        IERS 2010 Conventions

     c. a priori UT1 and polar motion: usno_finals.data
        (http://gemini.gsfc.nasa.gov/solve_save/usno_finals.erp)

 8.  A priori geophysical models:
 
     a. troposphere: Use of TRP files with total a priori atmospheric slant delay from GSFC based on VMF1
     
     b. solid Earth tide: IERS 2010 Conventions

     c. ocean loading: TPXO.7.2 model   

     d. pole tides: IERS 2010 Conventions

     e. Atmosphere loading: none

     f. antenna thermal deformation: IVS antenna thermal deformation model of Nothnagel 2008

     g. axis offsets:  values of the official list of VLBI antenna axis offsets antenna-info.txt
        based on gsfc_itrf2013.axo.txt were used  

 9.  Data type: Group delays

 10. Data editing: 5 deg elevation cutoff, 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 Version:  11.01  SOLVE release 2014.02.21

 14. Other information: 
     Field  2 X-Wob apriori                          
     Field  3 Y-Wob apriori                          
     Field 18 contains the session code
     Field 19 contains the duration of experiments
     Field 20 UT1 apriori                          
     Field 21 stations in session            

References:

Axel Nothnagel (2008) Short Note: Conventions on thermal expansion
modelling of radio telescopes for geodetic and astrometric VLBI;
Journal of Geodesy, DOI: 10.1007/s00190-008-0284-z.