Technical description of solution shad04it 1. Purpose of the solution: ITRF2004 solution 2. Analysis center: SHA ( Shanghai Observatory ) 3. Short narrative description of solution: Solution shad04it estimates position of all stations, coordinates of some sources, UT1, polar motion and their rates, daily nutation offsets for each session, all parameters are treated independently. No-net-rotation, no-net-translation constraints are imposed on the estimates of the station positions locally. Clock function for all stations except the reference one and atmosphere zenith path delay are modeled by a linear spline with the time span 60 and 20 minutes respectively. Parameters of these spline are estiamted as well together with other parameters. Data used spans from Apr. 1980 to Jan. 2005. The observation durations shorter than ~20 hours are not used. Sessions with the longest baseline length less than 2000km are not included as well. And all VCS sessions are excluded. Observations of 112 sources are excluded in solutions(Appendix B). 4. Estimated parameters: a. celestial frame: right ascension, declination of 189 sources for each session independently. (Appendix A. list of 189 sources) b. terrestrial frame: X, Y, Z of all sites for each session independently. c. Earth orientation: x, y, UT1-TAI, xdot, ydot, UT1dot, dpsi, deps. d. zenith troposphere: linear spline 20-min interval; rate constraint with reciprocal weights generally 50 ps/hr; NMF wet partial derivative (segmented). e. troposphere gradient: east and north gradients as well of the rate of their change was estimated for all stations offset and rate constraints with reciprocal weights 0.5 mm and 0.5 mm/day were applied (local). f. station clocks: quadratic (local) + linear spline with 1-hr interval (segmented); rate constraint with reciprocal weights generally 5.0E-14 g. baseline clocks: set in initial analysis - usually used (local) 5. Celestial reference frame: a. a priori source positions: from GIUB::/vlbi/IVS-AC, "MODFILE of source positions for IERS2004 campaign" b. source positions adjusted in solution: yes, some of them. Refer to Appendix A. If yes, c. definition of orientation: 632 sources are fixed to icrf-Ext1p, the formal errors of these sources are < 0.5mas both in right ascenson and declination in a global source solution using the same sessions. d. source position estimation: 189 local 6. Terrestrial reference frame: a. a priori station positions: sititrf2kp b. a priori station velocities: velitrf2kp c. reference epoch: 1997.0 d. station positions/velocities adjusted in solution: yes, positions only e. definition of origin, orientation, and their time evolution: no-net-translation and no-net-rotation of position with respect to sititrf2kp. All stations participate in equations of constraints. Equations of constraints are equally weighted. f. station parameter estimation: X, Y, Z, locally for all stations g. stations with constraints: NO! h. stations with discontinuous positions and date of discontinuity: no i. stations with nonlinear velocities: no j. relativity scale: the terrestrial reference frame is defined using the following metric tensor: G_oo = -(1 - (2W/c^2 + W^2/c^4) + 2L_g ) G_oa = -4W^a/c^3 G_ab = \delta_ab (1 + 2W/c^2 - 2L_g) ) Specifically, the old formula 29 in IERS Conventions 1992, page 127-136 was used, although it is known to have a deficiency. THIS METRIC TENSOR DOES NOT CONFORM IAU 2000 RESOLUTIONS! k. permanent tide correction: yes "Yes" means that both the permanent and the periodic tides have been modeled, so that the output station position is for after the removal of both the permanent and the periodic tidal effect. The model used includes tide displacements for zero frequency with Love numbers h2(freq=0) = 0.6074, l2(freq=0) = 0.0852 7. Earth orientation: a. a priori precession model: IERS 1996 b. a priori nutation model: IERS 1996 c. a priori short-period tidal variations in x, y, UT1 were taken into account in accordance with John Gipson's Model(JGR,1996) d. EOP estimation: X, Y, UT1, Xdot, Ydot, UT1dot, deps, dpsi each day with a priori error of 45 mas for pole and 3 ms for UT1, 45 mas/day and 3 ms/day for pole rate and UT1 rate to allow estimation for one-baseline sessions; deps and dpsi are relative to IAU 1976 precession and IAU 1980 nutation models. Time tag of EOP series is the middle epoch of the observing session. 8. A priori geophysical models: a. troposphere: NMF dry mapping function; Saastamoinen zenith delay calculated using logged pressure, temperature; a priori mean gradients from DAO weather model. b. solid Earth tide: IERS Conventions 1996, p.56-65, step 1 and step 2, anelasticity variant, including tides of the 3-rd order. c. atmosphere loading: pmvd97d( result from Dan MacMillan, Mar. 1997) 9. Data type: group delays 10. Data editing: 5 deg elevation cutoff 11. Software: Calc 9.12, SOLVE revision date 2004.11.09 References: 1. COORDINATES OF THE DEFINING SOURCES IN ICRF http://hpiers.obspm.fr/webiers/results/icrf/icrfdef.html 2. MacMillan, D.S. and C. Ma, Atmospheric gradients from very long baseline interferometry observations, Geophys. Res. Lett., 22, 1041-1044, 1995. 3. MacMillan, D.S. and C. Ma, Atmospheric gradients and the VLBI terrestrial and celestial reference frames, Geophys. Res. Lett., 24, 453-456, 1997. ---------------------------------------------------------------------------- Appendix A. ~~~~~~~~~~~ List of 189 sources with right ascension and declination estimated: 0008-421 0022-423 0032+612 0048-427 0107-610 0110-668 0116+319 0116-219 0127+084 0147-076 0153-410 0159-062 0201+088 0206-048 0210-075 0212-039 0213-013 0220-023 0230-790 0234-301 0235-618 0241+622 0307+380 0312-770 0331+022 0334+014 0355-483 0355-669 0407-658 0431-512 0450-743 0454-463 0454-810 0503-608 0517-726 0522-611 0524-485 0529+075 0534-340 0534-611 0549+192 0549-575 0600+219 0610+171 0736-332 0743-673 0809-493 0823-223 0823-500 0836+290 0936-853 0952+581 0959-443 1004-500 1012-448 1016-311 1022-665 1026-084 1034-374 1038+52B 1043+066 1045-620 1055-301 1056+212 1058+726 1105-680 1109-567 1117+146 1129-580 1143-287 1143-696 1148-671 1156-663 1228-113 1234-504 1236-684 1239+606 1245-454 1251-407 1320-446 1323+321 1325-558 1352-632 1355-416 1412-368 1420-679 1437+331 1448-648 1454-354 1505-496 1511-476 1519-294 1535+004 1554-643 1555-140 1556-245 1600+43A 1600+43B 1600-445 1600-489 1606-398 1611-710 1624-617 1628+216 1633-810 1646-506 1657-562 1659-621 1718-649 1725-795 1729-373 1733-565 1748-253 1806-458 1814-637 1815+531 1822-173 1824-582 1829-718 1843+400 1852-534 1903-802 1910+052 1919+086 1928-698 1929-457 1932+106 1934-638 1935-692 1936-623 1950-613 1952+138 2002-375 2005+403 2030-689 2051+745 2058-297 2058-425 2059-786 2102-659 2109-811 2115-305 2117-614 2120+099 2123-463 2128+048 2138-377 2142-758 2145+082 2146-783 2147+077 2152-699 2205-636 2211-388 2220-351 2229-172 2236-572 2239-631 2244-372 2300-307 2300-683 2306-312 2311-452 2314-340 2321-375 2333-415 2333-528 2344-514 2351-309 2353-686 3C48 4C55.17 CEN-A CYGNUS-A LSI61303 M104 NGC2484 NGC4261 NGC4278 NGC5077 NGC5141 NGC6034 NGC6500 NGC7720 SN1993J UG01841 UG03927 UGC02748 VELA-G Appendix B. ~~~~~~~~~~~ List of 112 sources are not included in solution: 0218+357 0218+35A 0218+35B 1031+567 1830-21A 1830-21B 1947+079 0036-216 0043+246 0122-514 0201-440 0202-765 0207-078 0248+560 0252-712 0254-334 0335-122 0336-017 0340+044 0354+559 0428+205 0512+249 0515-674 0532+506 0614-349 0615-365 0622-441 0647-475 0700-465 0710+196 0727-365 0731-465 0802-276 0842-754 0844+387 0902+343 0925+504 0941-080 1015-314 1017+109 1020-103 1039-474 1049-650 1206-399 1215-457 1221-829 1222+216 1225-023 1239-044 1245-197 1303-827 1305-241 1328+254 1329-665 1334-649 1422+268 1439+327 1505+428 1511+238 1540-828 1603+573 1622+238 1713+218 1721+589 1740-517 1742-283 1809+170 1813-241 1827-360 1829-106 1830-211 1848+333 1855+031 1920+154 1934+207 1954+282 2022+542 2027+383 2044-168 2100+468 2141+175 2155+312 2209+184 2259-375 2353+816 3C343 3C343.1 4C+00.02 HD132742 HD32918 HR1099 M106 M77 M82 MRK003 NAQL93 NGC0253 NGC1167 NGC2110 NGC2146 NGC3079 NGC3690 NGC4151 NGC6166 NGC6240 NGC6946 OB338 SIGCRB UG00192 UGC01651 UXARI VELA