CORE-A079 (Continuous Observations of the Rotation of the Earth-A079) 2000 January 11 Notes prepared by Cynthia Thomas and Dan MacMillan,NVI/GSFC Schedule name: CA079.SKD on CDDISA Nominal Start: 18:00 U.T. on January 11 (day 011) first observation at 18:00 U.T. on 0552+398 for GC-HH-MA-TS first observation at 18:00 U.T. on 0119+115 for AP-WF Nominal Stop: 18:00 U.T. on January 12 (day 012) last observation at 17:55 U.T. on 0454-234 for HH last observation at 17:59 U.T. on 0003-066 for AP-MA-WF last observation at 17:59 U.T. on 1334-127 for GC-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) 278 72828201 Fairbanks A GC 1 (TT) 321 40476601 HartRAO J HH 1 (TT) 178 72326201 Matera I MA 1 (TT) 310 72435701 Tsukuba T TS 1 (TT) 294 73452301 Westford E WF 1 (TT) 286 72097301 Purpose ======= Comparison of simultaneous CORE-A and NEOS sessions from 1997 to 1999 show that there are significant systematic differences between EOP estimates from the two networks. In addition, a bias can be seen between the CORE-A network of 1999, which replaced Hobart with Medicina, and the network for the previous two years. Further investigation is necessary to determine how to minimize this network sensitivity. Therefore, we plan to continue the CORE-A sessions in 2000 to provide more comparison data. The planned network for 12 of the sessions will be the 1998 network with Tsukuba replacing Westford, which will improve the formal uncertainties of polar motion estimates by a factor of 1.5-2.0. The remaining sessions will use Westford when Hobart is not available. 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, with the exception of the HartRAO baselines. The minimum SNR limits for the HartRAO baselines were set to 15 for X-bannd and 12 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 | 54.02| UT1-TAI | under 40% | | | | | | |Y-Wobble | 45.37| UT1-TAI | under 40% | | | | | | |UT1-TAI | 1.95| Y-WOBBLE | 45% | | | | | | |UT1-TAI Rate| 3.68| ------- | 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 ==== ========== 99OCT04 CORE-B605 99OCT05 CORE-A072 99OCT05 NEOS-A336 99OCT11 EUROPE-51 99OCT12 NEOS-A337 99OCT19 NEOS-A338 99OCT26 NEOS-A339 99NOV02 CORE-A074 99NOV02 NEOS-A340 99NOV09 NEOS-A341 99NOV16 NEOS-A342 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 ./ca079.skd for experiment CA079 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I x x x x x x xx x x x I 11 15 2.5 0048-097Ix x x x x xx x x x x xx xI 14 32 5.4 0059+581I x x x x x x x x x x x x I 12 112 9.4 0104-408I x x x x xx I 6 6 2.0 0119+115I x x xx x x x xxx x x xx xx x xx I 19 49 6.2 0119+041Ix x x xx x x x x x x xx x I 14 22 3.1 0208-512I I 0 0 .0 0229+131I x x x x x I 5 11 1.4 0235+164I x xx x x x I 6 26 3.5 CTA26 I x x x x x x x x x x x x I 12 18 2.9 0402-362I x x x I 3 3 1.0 0454-234I xx x xx xx x x xx x x xx xxI 17 24 5.9 0458-020I x x x I 3 5 .8 0528+134Ix x xx x x x x xx xx xx x xx x x x xxxx x x I 26 77 10.0 0537-441I I 0 0 .0 0552+398Ix x x xxx x x x x x xx x x xx xx xxx xx xx x x I 28 176 18.1 0556+238Ix x xx x x x xx xx x xx x x x x I 18 26 2.8 0637-752I I 0 0 .0 0727-115I x x xx xx x x x x x xxx x xxx x x x x xI 23 44 8.9 0749+540I x x x x x x x x x x I 10 88 7.6 0804+499Ix x x x xx x x x x x x x I 13 91 8.6 0805+410I x I 1 3 .2 0823+033Ix x xx xx x x xx x xxx xxx xx xxx I 22 40 5.8 OJ287 I x x x x x x xx x x x x I 12 35 4.1 0919-260I x x x x x I 5 5 2.0 0920-397I I 0 0 .0 4C39.25 I x xx x x x x xx x xx x xx x x x x x xx I 22 137 13.9 OK290 Ix x x xx x x x x x I 10 10 1.1 0955+476I x I 1 3 .3 1034-293Ix x x x x xI 6 6 1.1 1044+719I x x x x x x x x x x xI 11 94 7.8 1053+815I I 0 0 .0 1057-797I I 0 0 .0 1104-445I I 0 0 .0 1124-186Ix xx x xx x x x x x xx x x xx I 17 26 6.1 1128+385I x x x x I 4 13 1.1 1144-379I xx x x x I 5 5 1.7 1219+044Ixx x x x xx x xx x x xxxx xxx xx xI 22 46 6.5 1255-316I x xx x I 4 4 2.6 1300+580I I 0 0 .0 1313-333I I 0 0 .0 1334-127I xx x xx x x x xx I 10 16 4.3 1351-018I x x x x x x x x I 8 12 1.8 1357+769I x x x x x x x I 7 66 5.5 1424-418I x I 1 1 .3 1451-375I I 0 0 .0 1606+106I x xxx x x x x x x x x x x xx x xx xxx xxI 24 62 8.2 1622-253I xx xx xx x x x xx x xx xx I 16 18 4.4 NRAO512 I xx x x xx xx x x x x x x x x x xx x xx x x xI 25 153 15.6 1726+455I x I 1 6 .6 1739+522I xI 1 6 .5 1741-038Ix x x xx xx x x xxx x xxx x xx x xx xxx xxI 27 62 9.9 1749+096I x x x x x x I 6 27 3.8 1815-553I I 0 0 .0 1908-201I I 0 0 .0 1954-388I x x xx x x I 6 6 2.0 1958-179I I 0 0 .0 2052-474I I 0 0 .0 2121+053I xxx xx xx x xxx xxx xx xx x x x x xxx x xx I 28 87 12.4 2128-123I xx x x x x xx x xx x x xI 14 16 4.4 2145+067I x x x I 3 5 .7 2234+282Ix x xx x xxx x x x x x x x x x x I 18 59 6.6 2255-282I xx x x xx I 6 8 2.8 Total scans, obs: 583 1862 Average number of obs. per baseline per source (normalized by up-time) = 4.5 Min = .0 Max = 38.1 (Baseline Gc-Ts on 0727-115) RMS = 6.5 Total time: 1440 minutes ( 24.0 hours). Key: Ap=ALGOPARK Gc=GILCREEK Hh=HARTRAO Ma=MATERA Ts=TSUKUB32 Wf=WESTFORD Ap Gc Hh Ma Ts Wf Avg % obs. time: 23 36 22 48 34 42 34 % cal. time: 3 3 2 3 3 3 3 % slew time: 56 23 35 19 10 13 26 % idle time: 17 36 39 28 51 40 35 # of tapes : 1.5 .6 .4 .8 .6 .7 total # scans: 278 321 178 310 294 286 277 # scans/hour : 11 13 7 12 12 11 11.6 Avg scan (sec): 72 98 109 135 102 127 107 # OF OBSERVATIONS BY BASELINE | Ap Gc Hh Ma Ts Wf StnTotal -------------------------------------- Ap|278 173 44 133 86 254 690 Gc| 321 25 121 229 164 712 Hh| 178 157 53 54 333 Ma| 310 124 159 694 Ts| 294 86 578 Wf| 286 717 Number of 2-station scans: 301 Number of 3-station scans: 120 Number of 4-station scans: 106 Number of 5-station scans: 55 Number of 6-station scans: 1 Total # of scans, observations: 583 1862 Average baseline components for all observations Average XY = 5423. Average XZ = 4617. Average YZ = 4666. Average length = 6259.