Technical description of session EOP solution pul2010a.eopi Last update: 2010.09.30 1. Purpose of solution: UT1 estimates from intensive sessions 2 - Analysis Center: Pulkovo observatory (PUL) 3. Short narrative description of solution: Reduction model follows IERS Conventions (2003). Wet tropospheric delay and clock offset are modelled as random walk stochastic process and estimated using Kalman filter technique. The main differences with the previous solutions are: - none (the first PUL solution) 4. Estimated parameters: a. celestial frame: No b. terrestrial frame: No c. Earth orientation: UT1-UTC d. zenith troposphere: wet delay e. troposphere gradient: No f. station clocks: Polynomial + random walk process 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: VTRF2008 b. a priori station velocities: VTRF2008 c. reference epoch: 2000.0 d. station positions/velocities adjusted in solution: No 7. Earth orientation: a. a priori precession model: IAU2000A b. a priori nutation model: IAU2000A c. a priori short-period tidal variations in x, y, UT1: IERS Conventions (2003) zonal tidal variations are included in EOP daily and subdaily variations are not included in EOP d. EOP estimation: UT1-UTC 8. A priori geophysical models: a. troposphere: Saastamoinen model for HZD, VMF1 mapping function b. solid Earth tide: IERS Conventions (2003) c. ocean loading: IERS Conventions (2003) d. atmosphere loading: GSFC time series 9. Data type: delays, NGS cards 10. Data editing: Only data with zero quality flag in NGS file are used; supplemental editing of outliers is applied during adjustment when necessary 11. Data weighting: Observations are weighted using std reported in NGS file and a priori additive variance depending on session and/or station. Elevation depending weighting is applied. 12. Standard errors reported: As derived from Kalman filter adjustment, without supplement correction 13 Software: OCCAM 14. Other information: 15. Contact: Zinovy Malkin (malkin@gao.spb.ru)