VieVS User Workshop 14 – 16 September, 2011 Vienna VIE_GLOB Hana Spicakova

VieVS User Workshop VIE_GLOB_V1d compatible with VieVS Version 1d parameters which can be estimated - from combination of more sessions station coordinates and velocities: TRF source coordinates: CRF Earth orientation parameters - session-wise as reduced parameters zenith wet delay troposphere gradients Earth orientation parameters station and source coordinates (not suitable for global estimation) input data datum free N-matrices (A T PA) and b-vectors (A T Pl) VieVS/DATA/LEVEL2 created within a „normal“ run of VieVS

Last GUI in VIE_LSM VieVS User Workshop data for VIE_GLOB will be stored in DATA/LEVEL2/

How to run VIE_GLOB VieVS User Workshop VieVS/COMPILE/VIE_GLOB_V1d/vie_glob.m path to the directory TEST_LEVEL2 with LEVEL2 data the subdirectory TEST_OUT will be created in VieVS/OUT/GLOB/_ESTIMATES /_PLOTS eventually in: /CRF /TRF only sessions with a lower RMS than chosen (in this case RMS < 2) will be used in the global adjustment if ticked, N matrices and b vectors with reduced parameters from each session will be saved into VieVS/OUT/GLOB/BACKWARD_DATA INPUT OUTPUT

GUI for RF VieVS User Workshop Terrestrial Reference Frame Celestial Reference Frame

GUI for TRF VieVS User Workshop VieVS/DATA/GLOB/TRF/ DATUM/ REDUCE/ DISCONT/ VELOC/ VELOC/TIES/ the original VLBI-DISCONT.txt file is provided at the web site AC/data/VLBI-DISCONT.txt AC/data/VLBI-DISCONT.txt TRF_datum1.txt few_observations.txt const_velocity_8410.txttest.txt choose between NNT/NNR or NNT/ NNR /NNS

VieVS User Workshop GUI for CRF VieVS/DATA/GLOB/CRF/ DATUM/ FIXED_SOURCES/ REDUCE/ choose between NNR or NNR + translation in declination condition CRF_datum1.txt test.txt special_handling_39.txt

Theoretical background VieVS User Workshop Sort parameters in the N-matrix and b-vector Reduction of parameters always reduced: clock parameters, zwd and troposphere gradients can be reduced: EOP, stations and sources not suitable for global solution Stacking of the reduced normal equation systems globally estimated p. reduced p.

Constraints zwd, troposphere gradients, EOP constraints are chosen in VIE_LSM station coordinates and velocities relative constraints for velocity same velocity for all coordinate intervals at one station (e.g. antenna repair) same velocity at stations in the same area (e.g. Hobart26 and Hobart12) datum definition source coordinates datum definition VieVS User Workshop 20119

Datum definition Station coordinates and velocities NNT/NNR condition constrained 12 parameters Helmert transformation (3 translation and 3 rotation components + their time derivatives w.r.t. time) NNT/NNR/NNS condition constrained 14 parameters Helmert transformation (3 translation, 3 rotation components and 1scale component + their time derivatives w.r.t. time) Source coordinates NNR condition NNR condition + 1 translation parameter parameter dz accouns for a global translation of the source coordinates in declination, caused e.g. by inaccuracy of the tropospheric propagation correction for sources observed at low elevations) (Feissel-Vernier et al. (2006)) fixing selected sources to a priori coordinates VieVS User Workshop

VieVS User Workshop Final solution applying of the constraints final solution for global parameters estimates are stored as a structure array in Matlab format and as a txt file VieVS/OUT/GLOB/_ESTIMATES/TEST_OUT/ globsol_TEST_LEVEL2.mat glob_results_TEST_LEVEL2.txt

Estimates - Example VieVS User Workshop VieVS/OUT/GLOB/_ESTIMATES/TEST_OUT /glob_results_TEST_LEVEL2.txt names of sessions number of sessions corrections to station a priori coordinates and their standard deviations [cm] corrections to station a priori velocities and their standard deviations [cm/y] stations which were used for NNT/NNR epoch of the coordinates [mjd] start, end [mjd] of the interval (time between breaks) sessions with RMS>maxRMS

VieVS User Workshop corrections to source a priori coordinates (RA, De) and their standard deviations [mas] Estimates - Example estimates of EOP: dx, dy pole [mas] dut1 [ms] dX, dY [mas] and their standard deviations

Results VieVS User Workshop „new catalogues“ (TRF and CRF) are created automatically in VieVS/OUT/GLOB/ TRF/TEST_OUT/trf_TEST_LEVEL2.txt and CRF/TEST_OUT/trf_TEST_LEVEL2.txt this new TRF catalogue can be used as input catalogue in VieVS

Plots VieVS User Workshop VieVS/OUT/GLOB/_PLOTS/TEST_OUT/ ant_activity_TEST_LEVEL2.eps ant_map_TEST_LEVEL2.eps stations in sessions included in the global adjustment map of stations, blue circles: station included in NNT/NNR red circles: station excluded from NNT/NNR

Plots VieVS User Workshop VieVS/OUT/GLOB/_PLOTS/TEST_OUT/ sou_activity_TEST_LEVEL2.eps sou_map_TEST_LEVEL2.eps sources in sessions included in the global adjustment map of sources, blue circles: source included in NNR red circles: source excluded from NNR

Processing of a long time span of data (20 years or more) Problems if e.g. EOP would be considered as global parameters (stacking at the overlapping time steps), the final N matrix would be too huge – not possible to handle it at a normal PC position of some sources is not stable enough to handle it as a constant value unequal observation time at the stations – at some stations the observation interval is not sufficient to estimate reliable velocity VieVS User Workshop

Processing of a long time span of data (20 years or more) Problems if e.g. EOP would be considered as global parameters (stacking at the overlapping time steps), the final N matrix would be too huge – not possible to handle it at a normal PC position of some sources is not stable enough to handle it as a constant value unequal observation time at the stations – at some stations the observation interval is not sufficient to estimate reliable velocity VieVS User Workshop

Processing of a long time span of data (20 years or more) Problems if e.g. EOP would be considered as global parameters (stacking at the overlapping time steps), the final N matrix would be too huge – not possible to handle it at a normal PC position of some sources is not stable enough to handle it as a constant value unequal observation time at the stations – at some stations the observation interval is not sufficient to estimate reliable velocity VieVS User Workshop

In these cases the concerned parameters have to be excluded from the global adjustment by a session-wise reduction. The vector x 2 we get from a so-called back solution for each session: Covariance matrix VieVS User Workshop Reduction globally estimated p. reduced p. After running VIE_GLOB we know the vector x 1 (global parameters)

Reduction If the button in the 1st GUI of VIE_GLOB is ticked, all needed parameters for a back solution will be stored in: VieVS/OUT/GLOB/BACKWARD_DATA/TEST_OUT/ i.e., N 21, N 22 and b 2 for each session + some other information, e.g. description of the columns VieVS User Workshop After finishing of VIE_GLOB run VieVS/OUT/GLOB/backward_solution.m in the source code you have to specify the name of the TEST_OUT and TEST_LEVEL2 directories and which reduced parameters you want to estimate The estimated values will be written into.txt files in VieVS/OUT/GLOB/BACKWARD_SOLUTION/TEST_OUT/ as ant_TEST_LEVEL2.txt eop_TEST_LEVEL2.txt sou_TEST_LEVEL2.txt tgr_TEST_LEVEL2.txt zwd_TEST_LEVEL2.txt

Backward solution: zwd VieVS User Workshop The estimates for each station can be plotted with: VieVS/OUT/GLOB/ plot_backward_zwd.m

VieVS User Workshop Backward solution: tgr The estimates for each station can be plotted with: VieVS/OUT/GLOB/ plot_backward_tgr.m

VieVS User Workshop Backward solution: EOP The estimates for each EOP can be plotted with: VieVS/OUT/GLOB/ plot_backward_eop.m

VieVS User Workshop Backward solution: antenna coordinates The estimates for each station can be plotted with: VieVS/OUT/GLOB/ plot_backward_ant.m

VieVS User Workshop Backward solution: source coordinates The estimates for each source can be plotted with: VieVS/OUT/GLOB/ plot_backward_sou.m

VieVS User Workshop Thank you for your attention!