CORE-A049 (Continuous Observations of the Rotation of the Earth-A049) 1998 November 17 Notes prepared by Cynthia Thomas, NVI/GSFC Schedule name: CA049.SKD on CDDISA Nominal Start: 18:00 U.T. on November 17 (day 321) first observation at 18:00 U.T. on 1044+719 for AP-Gc-MA-WF first observation at 18:00 U.T. on 0402-362 for HH-HO Nominal Stop: 18:00 U.T. on November 18 (day 322) last observation at 17:50 U.T. on 0528+134 for HO last observation at 17:52 U.T. on 0119+115 for HH-MA last observation at 17:53 U.T. on 1334-127 for WF last observation at 17:56 U.T. on 1219+044 for AP-GC 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) 305 72828201 Fairbanks A GC 1 (TT) 320 40476601 HartRAO J HH 1 (TT) 217 72326201 Hobart H HO 2 (HDT) 158 72425901 Matera I MA 3 (HDT) 291 72435701 Westford E WF 1 (TT) 329 72097301 Purpose ======= The CORE-A sessions measure EOP simultaneously with NEOS, using an independent network of comparable or better precision. The purpose of the parallel sessions is to assess the true accuracy of VLBI results for EOP by comparing the measurements from the two networks. Note on Core-A 1998 results to date: As of early January 1998, 18 CORE-A sessions from 1997 have been completed and analyzed. The comparisons of the EOP results from these sessions with NEOS are quite encouraging. The levels of agreement for daily measurements are 125 micro-arcsec for X-pole, 105 micro-arcsec for Y-pole, and 7.4 microsec for UT1 and 20 microsec for LOD. The corresponding Chi-squares per degree of freedom are 1.2, 1.3, 2.2, and 2.4, respectively. The goals for EOP in the Mark IV era are 25 micro-arcsec for the pole components and 1 microsec for UT1. (No goal for LOD has been set.) We have a lot of work remaining, but these goals are not out of reach. Schedule ======== This is a new schedule generated by C. Thomas with the automatic mode of sked. The following are the characteristics of the schedule: 1) This schedule was optimized for sky coverage. 2) Only the observations in the previous hour of the schedule were considered for the minor options. The best 70% 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 twenty minutes. 5) The minimum SNR limits for most baselines were set to 20 for X-band and 15 for S-band. 6) This schedule was made using 59 sources which helped improve the sky coverage. 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 98AUG11 (CA042), 98AUG17 (EUROPE-44), and 98AUG25 (CORE-A043) experiments. Station Information =================== This is the first experiment with HartRAO participating as a thin tape station. HartRAO is scheduled to record on thin tape in high density during this experiment. 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 ./ca049.skd for experiment CA049 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066Ix x x x x x x xx x xI 11 17 2.8 0048-097I x x x x x x x xx x x x x I 13 29 4.9 0059+581I x xx x x x x x x x x x x x x x x x I 18 105 10.5 0104-408I x x xx xx xx x I 9 13 4.2 0106+013Ix xx x x xI 6 6 .9 0119+115I xx xx x xx x x x x x x I 13 29 3.7 0119+041I x x xx x x I 6 14 2.0 0208-512I x x x x x x I 6 6 2.4 0229+131I x x x x x x x x x x I 10 33 4.3 0235+164Ix x x I 3 3 .4 CTA26 Ix x x x xx x I 7 13 2.1 0402-362I x x xxx xx x xI 9 9 3.1 0454-234Ix x x x x xxxx x xx I 12 20 4.2 0458-020I x xx x x x I 6 10 1.6 0530-727I I 0 0 .0 0528+134I x x x x x xx x x x x x x xxx xI 17 51 6.9 0537-441I I 0 0 .0 0552+398I x x x xx xx x x x x x xxx x x xx I 19 89 10.4 0556+238I x x I 2 4 .4 0637-752I x x x x x x x x xI 9 9 3.7 0718+793I x x x x x x x I 7 21 2.1 0727-115Ix x x x x x x x x x x xx x x xI 16 27 5.6 0749+540I x x x x x x x xx x x x x I 13 72 7.3 0804+499Ix x x x x x x x x x I 10 46 5.1 0805+410I x x x x I 4 18 1.8 0823+033I x x xx x x I 6 21 3.1 OJ287 I x x I 2 2 .2 0919-260I x x x I 3 3 1.2 0920-397I x I 1 1 .3 4C39.25 I x x x x x xx x xx x x x x xx xx xx xxI 22 94 9.7 OK290 I x x x x xx I 6 14 1.5 0955+476Ix x x xx x x x x x x x x x x xxx x I 19 86 10.1 1034-293Ix x x x x x I 6 6 1.4 1044+719I x x x x x x x x x x x x x xx x x x x I 19 99 9.9 1053+815I I 0 0 .0 1057-797I x x x x x x xI 7 7 2.9 1104-445I I 0 0 .0 1124-186Ix x x x x x x x x x x I 11 15 3.1 1128+385Ix x x x xx xx x x xx I 12 29 2.5 1144-379I x x x x x I 5 9 2.9 1219+044I x x I 2 4 .6 1255-316I x I 1 1 .6 1300+580I x x x x I 4 12 1.2 1308+326Ix x x x x xx xx xx xI 12 26 2.5 1313-333I x x x x x x x I 7 7 2.8 1334-127I x x x x x xx x x xx I 11 13 2.2 1351-018I x x x x I 4 8 1.3 1357+769I x x x x x x x x x x x x x x x x x x I 18 99 9.9 1424-418I x x xx x x I 6 6 2.0 1451-375I I 0 0 .0 1606+106Ix x x x x x x x xx x x xI 13 23 3.0 1610-771I x x x x x x x x x I 9 9 3.7 1622-253I I 0 0 .0 NRAO512 I xx x x x x x x x x x x x xx x x x I 18 88 10.4 1726+455I x x x I 3 12 1.4 1739+522I x x xx x x x x x x x x x x xx x x x I 19 103 10.9 1741-038Ix x x x x x x x x x xx xx x xx xx x xI 21 50 7.9 1749+096I x x xx x x x x x x xx x x x x I 16 51 7.1 1815-553I x I 1 1 .4 1908-201I xx x xx x xI 7 7 1.6 1921-293I x x xx x xx xx x x xI 12 12 2.3 1954-388I x x xx x x x x I 8 8 2.7 1958-179I x xx x x x x I 7 9 1.8 2005-489I I 0 0 .0 2052-474I I 0 0 .0 2121+053Ix xx x x x x I 7 11 1.6 2128-123Ix x x xx x x xI 8 8 1.3 2134+00 I x x I 2 2 .3 2145+067I x x x x x x x x x x I 10 24 3.3 2234+282Ix xx x x xI 6 27 2.8 2255-282I x x x x x xxI 7 9 2.9 Total scans, obs: 584 1660 Average number of obs. per baseline per source (normalized by up-time) = 3.4 Min = .0 Max = 28.6 (Baseline Gc-Ho on 0727-115) RMS = 5.5 Total time: 1437 minutes ( 24.0 hours). Key: Ap=ALGOPARK Gc=GILCREEK Hh=HARTRAO Ho=HOBART26 Ma=MATERA Wf=WESTFORD Ap Gc Hh Ho Ma Wf Avg % obs. time: 25 44 38 30 43 47 38 % cal. time: 3 3 2 1 3 3 3 % slew time: 52 18 42 21 17 12 27 % idle time: 17 33 16 45 35 36 30 # of tapes : 1.6 .8 .6 1.9 2.5 .8 total # scans: 305 320 217 158 291 329 270 # scans/hour : 12 13 9 6 12 13 11.3 Avg scan (sec): 72 119 151 166 128 124 126 # OF OBSERVATIONS BY BASELINE | Ap Gc Hh Ho Ma Wf StnTotal -------------------------------------- Ap|305 233 28 5 146 295 574 Gc| 320 20 45 176 245 744 Hh| 217 109 122 35 318 Ho| 158 20 3 573 Ma| 291 178 753 Wf| 329 358 Number of 2-station scans: 291 Number of 3-station scans: 147 Number of 4-station scans: 133 Number of 5-station scans: 13 Number of 6-station scans: 0 Total # of scans, observations: 584 1660 Average baseline components for all observations Average XY = 4892. Average XZ = 4637. Average YZ = 4029. Average length = 5789.