Technical description of solution bkg2016a.crf.txt 1. Purpose of solution: CRF 2 - Analysis Center: Federal Agency for Cartography and Geodesy (BKG Leipzig) and Institute of Geodesy and Geoinformation of the University of Bonn (IGGB) 3. Short narrative description of solution: VLBI data from Jan 1984 to OCT 2016 were used for this solution. The orientation of CRF is defined by no-net-rotation constraints for 295 defining sources related to the ICRF2 catalogue. The TRF is defined by no-net-translation and rotation constraints for the coordinates and velocities of 25 sites related to VTRF2008a. Positions of GILCREEK, HRAS_085, PIETOWN are modeled with spline. 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 made by program make_vmf_trp_file from GSFC. The atmospheric pressure loading time series provided by the Goddard VLBI group which are available on the Web at http://lacerta.gsfc.nasa.gov/aplo (Petrov & Boy, 2004) are used. 4. Estimated parameters: a. celestial frame: right ascension, declination b. terrestrial frame: X, Y, Z, Xdot, Ydot, Zdot and coordinates series of stations AIRA CHICHI10 CTVASTJ DSS13 ISHIOKA KASHIM11 KASHIM34 KOGANEI KUNMING PT_REYES RAEGYEB SEJONG SEST SINTOTU3 TIANMA65 TIDBIN64 TIGOCONC TSUKUB32 UCHINOUR VERAISGK VERAMZSW WETTZ13N WIDE85_3 YEBES40M estimated in respective session, spline coefficients for stations GILCREEK, HRAS_085, PIETOWN c. Earth orientation: X-pole, Y-pole, UT1-TAI, Xdot, Ydot, UT1dot, X-nutation, Y-nutation d. zenith troposphere: 1h piece-wise linear functions, rate constraint generally 50 ps/hour, VMF1 wet partial derivative (segmented) e. troposphere gradient: east and north offset, offset constraint 0.5 mm, rate constraint 2.0 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: ICRF2 b. source positions adjusted in solution: Yes c. definition of orientation: no-net-rotation of sources with respect to ICRF2 for 295 defining sources marked in the ITRF2 catalogue 6 - Terrestrial reference frame: a. a priori station positions: VTRF2008a b. a priori station velocities: VTRF2008a c. reference epoch: 2000.0 d. definition of origin, orientation, and their time evolution: no-net-translation and no-net-rotation of position with respect to VTRF2008a for 25 stations: ALGOPARK BR-VLBA DSS45 FD-VLBA FORTLEZA HARTRAO HOBART26 KASHIMA KAUAI KOKEE LA-VLBA MATERA MK-VLBA NL-VLBA NOTO NRAO20 NRAO85_3 NYALES20 ONSALA60 RICHMOND SANTIA12 SC-VLBA SESHAN25 WESTFORD WETTZELL no-net-translation and no-net-rotation of velocity with respect to VTRF2008a for the same 25 stations: ALGOPARK BR-VLBA DSS45 FD-VLBA FORTLEZA HARTRAO HOBART26 KASHIMA KAUAI KOKEE LA-VLBA MATERA MK-VLBA NL-VLBA NOTO NRAO20 NRAO85_3 NYALES20 ONSALA60 RICHMOND SANTIA12 SC-VLBA SESHAN25 WESTFORD WETTZELL e. stations with nonlinear velocities: GILCREEK, HRAS_085, PIETOWN 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) d. EOP estimation: X, Y, UT1, Xdot, Ydot, UT1dot, X-nutation, Y-nutation, each session for the middle epoch of it, and X-nutation and Y-nutation are relative to IAU2000A/2006 Nutation/Precession models, also X, Y, UT1, Xdot, Ydot, UT1dot, Deps, Dpsi, each session for the middle epoch of it, and Deps and Dpsi are relative to the IAU 1976 precession and IAU 1980 nutation models. 8. A priori geophysical models: a. troposphere: Use of TRP files with hydrostatic a priori atmospheric slant delay made by program make_vmf_trp_file 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: atmospheric pressure loading time series provided by GSFC (available at http://lacerta.gsfc.nasa.gov/aplo/aplo_bds.tar.bz2) 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 h. a priori gradients: values from GSFC Data Assimilation Office (DAO) model, gsfc_dao_gmao_mgr.txt 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 18 contains the session code Field 19 contains the duration of experiments 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. L. Petrov, J.-P. Boy, Study of the atmospheric pressure loading signal in VLBI observations, Journal of Geophysical Research, 10.1029/2003JB002500, Vol. 109, No. B03405, 2004.