Technical description of solution mao05it1_dsnx
1. Purpose of solution: VLBI solution for the ITRF2004 initiative,
the output is systems of normal equations.
2. Analysis Center: Main Astronomical Observatory, NASU, Kiev, Ukraine
3. Short narrative description of solution: Dual-band VLBI observations from
1980 till 2005 were analysed for this solution. The orientation of CRF is
defined by the No-Net-Rotation constraint for 25 "DEFINING" sources related
to ICRF-Ext.1 (0014+813, 0133+476, 0235+164, 0556+238, 0642+449, 0718+792,
0749+540, 0804+499, 0805+410, 0955+476, 1053+815, 1128+385, 1219+044,
1308+326, 1418+546, 1606+106, 1642+690, 1726+455, 1745+624, 1823+568,
1954-388, 2037+511, 2113+293, 2136+141 and 2145+067). The TRF is defined
by No-Net-Translation and Rotation constraints for the coordinates of eight
stations (ONSALA60, WETTZELL, HARTRAO, ALGOPARK, KOKEE, WESTFORD, FORTLEZA
and HOBART26) related to ITRF2000. Constraints are not applied on the
output.
4. Estimated parameters:
a. celestial frame: right ascension, declination
b. terrestrial frame: X, Y, Z
c. Earth orientation: x, y, UT1-UTC, dX, dY
d. zenith troposphere: random walk model for stochastic estimation
e. troposphere gradient: random walk model for stochastic estimation
f. station clocks: random walk model for stochastic estimation
g. baseline clocks: no
h. other: no
5. Celestial reference frame:
a. a priori source positions: ICRF-Ext.1
b. source positions adjusted in solution: yes
c. definition of orientation: NNR of position of 25 DEFINING radio
sources related to ICRF-Ext.1
6. Terrestrial reference frame:
a. a priori station positions: ITRF2000
b. a priori station velocities: ITRF2000
c. reference epoch: 1997.0
d. station positions adjusted in solution: Yes
e. definition of origin, orientation, and their time evolution:
No-Net-Translation and No-Net-Rotation of position with respect to
ITRF2000 for eight stations.
7. Earth orientation:
a. a priori precession model: IAU-2000
b. a priori nutation model: IAU-2000A
c. Short-period tidal variations in x, y, UT1:
Model used according to: Ray, et al. (1994) as published in
IERS Conventions (2003).
d. EOP estimation: x, y, UT1-UTC, dX and dY
8. A priori geophysical models:
a. troposphere: Saastamoinen hydrostatic zenith delay, estimated from
observations wet zenith delay, MTT mapping functions for wet and
hydrostatic components when meteo parameters are available and NMF
mapping functions in other case.
b. solid Earth tide: IERS Conventions (2003)
c. ocean loading: IERS Conventions (2003)
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.
12. Standard errors reported: Reported formal errors are derived from
least-squares estimation propagated from data uncertainties.
13. Software: SteelBreeze-2005.02.20