CORE-A066 (Continuous Observations of the Rotation of the Earth-A066) 1999 July 13 Notes prepared by Cynthia Thomas and Nancy Vandenberg,NVI/GSFC Schedule name: CA066.SKD on CDDISA Nominal Start: 18:00 U.T. on July 13 (day 194) first observation at 18:00 U.T. on 4C39.25 for AP-GC-Mc first observation at 18:00 U.T. on 1921-293 for HH-HO-TS Nominal Stop: 18:00 U.T. on July 14 (day 195) last observation at 17:51 U.T. on 0458-020 for AP last observation at 17:55 U.T. on 1726+455 for GC-MC last observation at 17:59 U.T. on 1954-388 for HH-HO-TS Correlator: Washington **Frequency Sequence**: CDP-WBCA - Modified CDP wide-band SX sequence. (720 MHz wide at X, 125 MHz wide at S), Shifted to avoid RFI at Matera 1 letter 2 letter Station Code Code # of tapes # of obs Occupation Code Algonquin G AP 2 (HDT) 255 72828201 Fairbanks A GC 1 (TT) 322 40476601 HartRAO J HH 1 (TT) 194 72326201 Hobart H HO 2 (HDT) 195 72425901 Medicina B MC 3 (HDT) 316 72308801 Tsukuba T TS 1 (TT) 378 73452301 Purpose ======= The purpose of CORE-A is to validate the CORE concept of measuring EOP continuously using different networks. Comparisons of the EOP results from simultaneous sessions in 1997 and 1998 have shown fairly good agreement, but there are some puzzling systematic differences. It is hoped that additional data to be obtained during 1999 will contribute to understanding this data set. The network for CORE-A includes Fairbanks, HartRAO, Algonquin, Westford, Matera, Medicina, Tsukuba, and Hobart. Tsukuba will begin to participate in CORE-A after April 1. This set of 8 stations includes two geographically paired stations: Algonquin/Westford and Matera/Medicina. For purposes of comparison with NEOS, we want to keep this network as constant as possible but we need to limit the network size to 6 stations. Whenever Tsukuba is available during non-network periods, we will drop Matera. Whenever Hobart is available we will drop Westford. Schedule ======== This is a new schedule generated by C. Thomas with the automatic mode of sked. Following are the characteristics of the CORE-A schedule file: 1) This schedule was optimized for sky coverage. 2) Only the observations in the previous 3 hours of the schedule were considered for the minor options. The best 50% of the configurations were considered for minor options. 3) The "minor options" were set to select observations to maximize the total number of observations, to minimize the idle time between scans, and to minimize time between scans on the same source by thirty minutes. 5) The minimum SNR limits for the baselines were set to 20 for X-band and 15 for S-band. 6) This schedule was made using 63 sources which helped improve the sky coverage. Simulation Results ================== Simulated data from this schedule was used in a global solution to estimate the formal errors. The table below lists the formal errors for Earth orientation parameters. These results meet the simulation goals for the CORE-A network. Also shown in the table are the maximum correlations between the Earth orientation parameters and other parameters. The results from the 1998 CORE-A network showed very high (~70%) correlations between certain parameters and this was one of the motivations for re-design of the network. ____________________________________________ | | | | | | EOP |Formal| Other | | |Parameters |Errors|Parameters|Correlation| |____________|______|_________ |___________| | | | | | |X-Wobble | 33.01| -------- | under 40% | | | | | | |Y-Wobble | 34.61| Tsukuba Z| 45% | | | | | | |UT1-TAI | 1.98| Tsukuba Y| 43% | | | | | | |UT1-TAI Rate| 4.24| ------- | under 40% | | | | | | ____________________________________________ Flux Information ================ Several years ago John Gipson wrote a program called snranal which compares the measured performance of an experiment with respect to the predicted. One of the things this program calculates is an empirical flux density for each source. Recently J. Gipson compared the fluxes generated by this program with those from more careful modeling. The agreement is generally good (~15%) for those sources which have been observed more than 20 times. In order to account for changes in the flux catalog since the last update, J. Gipson adjusted the fluxes in the flux catalog for the sources in the current source catalog using the following databases: Date Experiment ==== ========== 99APR06 NEOS-A310 99APR06 CORE-A059 99APR13 NEOS-A311 99APR19 IRIS-S137 99APR20 NEOS-A312 99APR20 CORE-A060 99APR26 EUROPE-48 99APR27 NEOS-A313 99MAY03 IRIS-S138 99MAY04 NEOS-A314 99MAY05 CORE-B403 99MAY11 NEOS-A315 99MAY18 NEOS-A316 Procedures ========== Please generate the procedures for this session using drudg. Correlation ========== This experiment will be correlated at the Washington Correlator with all baselines being correlated. SKED Summary from file ./ca066.skd for experiment CA066 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I xx x x xx x xxx x xx x x xx x x x I 20 22 3.6 0048-097Ix x x x xxx x x x I 10 29 5.2 0059+581I x x x x x x x x x x x x x x x I 15 78 7.8 0106+013I I 0 0 .0 0119+115I x x xx x x x x xx x xxx x x I 16 26 3.3 0119+041I x x x xx x xx xx xx x xx x x x x x x xxI 23 29 4.2 0229+131I x x x x x I 5 7 .9 0235+164I x x x x x x x I 7 24 3.2 3C84 I I 0 0 .0 CTA26 I x x xx xx x xxxx x xI 13 13 2.1 0402-362Ix x x xx x x x x x xx xx I 14 14 4.1 0454-234Ix x x xx x x x xx xxx x x x x xxxx xx I 23 35 6.9 0458-020Ix x x x x x xx xxx I 11 13 2.1 0528+134I x x x x x x x x x x xx x xx x x x x I 19 39 5.3 0552+398I x x x x x xx xx xx x x x xx x x x x xI 21 85 10.3 0556+238I xx x x x x x x x x x xI 12 16 1.7 0718+793I x x x x x I 5 5 .5 0727-115Ixx x xx x xx x xxx xx xx x x x xx xI 22 45 9.5 0749+540I x x x x x x x x x x x x x x xI 15 84 8.4 0804+499I x x x x x x I 6 24 2.6 0805+410I x I 1 6 .6 0823+033Ixxx x x x xx xx x x x x x x xx xx I 20 26 3.8 OJ287 I xx x x x x x x x x x xx x xI 15 40 5.0 0919-260I I 0 0 .0 0920-397I x I 1 1 .3 4C39.25 I x x x xx x x x x x xx x x x x I 16 66 8.5 OK290 I x xxx x x I 6 6 .6 0955+476I x x x I 3 12 1.4 1034-293I x x xxx x x xx x x xx x x x I 16 16 3.0 1044+719I x x x x x x x x x x xI 11 57 5.7 1053+815I x x x x xI 5 24 2.4 1124-186I x x x xxx x x xxx xx x xx x xx x x xI 22 34 6.6 1128+385I x x x x x I 5 15 1.3 1144-379I xx x x x xx xx x x x x I 13 15 4.6 1219+044I xxx x xxx xx xx x x x x x x x xxI 20 24 3.4 3C273B I I 0 0 .0 1255-316I x I 1 1 .2 1300+580I x x x I 3 18 1.8 1313-333I x I 1 1 .1 1334-127I x x x x x I 5 5 2.3 1351-018I x x xx x x xx x x I 10 12 1.9 1357+769I x x x x I 4 21 2.1 1424-418I x x x x I 4 4 1.2 1451-375I I 0 0 .0 1606+106Ix x x x xxx x x xxx x xx xx x xx x x xx I 24 54 7.3 1622-253Ix x x xx x xx x x xx x x xx xx x I 19 25 4.7 NRAO512 Ix xx x x x x x x x x xx x I 14 46 4.8 3C345 I I 0 0 .0 1726+455Ix x x x x x x I 7 24 2.8 1739+522Ix x x x x x x xx x x x xx I 14 72 7.5 1741-038Ix x x xxx x xx xxxx xx xxx x xx xx xxxxx I 28 60 9.7 1749+096I x x xxx x I 6 19 2.8 1908-201I x x xx I 4 4 .7 1921-293I x xx x x x x x xx x xx I 13 15 2.5 1954-388I x x x x xx xx x x x xx xI 14 18 5.4 1958-179Ix xx xxx x xxx x x x x x I 15 21 3.7 2121+053I x x x x x x xx xx xx xx x xx xx I 19 52 7.6 2128-123I x x x x I 4 4 1.7 2134+00 I I 0 0 .0 2145+067I x x x xx x x I 7 21 3.0 2234+282Ix x x x x x x x x x xx x x x I 15 27 2.8 3C454.3 I I 0 0 .0 2255-282I x x x x x x I 6 8 1.7 Total scans, obs: 648 1462 Average number of obs. per baseline per source (normalized by up-time) = 3.3 Min = .0 Max = 31.5 (Baseline Ho-Ts on 1741-038) RMS = 5.4 Total time: 1440 minutes ( 24.0 hours). Key: Ap=ALGOPARK Gc=GILCREEK Hh=HARTRAO Ho=HOBART26 Mc=MEDICINA Ts=TSUKUB32 Ap Gc Hh Ho Mc Ts Avg % obs. time: 23 34 24 23 33 36 29 % cal. time: 2 3 2 2 3 4 3 % slew time: 54 22 35 24 34 26 32 % idle time: 19 39 37 50 28 32 34 # of tapes : 1.5 .6 .4 1.4 2.1 .6 total # scans: 255 322 194 195 316 378 276 # scans/hour : 10 13 8 8 13 15 11.5 Avg scan (sec): 78 91 109 102 92 82 92 # OF OBSERVATIONS BY BASELINE | Ap Gc Hh Ho Mc Ts StnTotal -------------------------------------- Ap|255 197 32 15 145 109 563 Gc| 322 11 45 135 226 500 Hh| 194 55 144 44 296 Ho| 195 12 163 483 Mc| 316 129 590 Ts| 378 492 Number of 2-station scans: 370 Number of 3-station scans: 192 Number of 4-station scans: 86 Number of 5-station scans: 0 Number of 6-station scans: 0 Total # of scans, observations: 648 1462 Average baseline components for all observations Average XY = 5515. Average XZ = 6044. Average YZ = 5491. Average length = 7409.