CORE-A031 (Continuous Observations of the Rotation of the Earth-A031) 1998 March 10 Notes prepared by Cynthia Thomas, NVI/GSFC Schedule name: CA031.SKD on CDDIS Nominal Start: 18:00 U.T. on March 10 (day 069) first observation at 18:00 U.T. on 0229+131 for AP-GC-MA-WF first observation at 18:00 U.T. on 1057-797 for HH-HO Duration: 24 hours Nominal Stop: 18:00 U.T. on March 11 (day 070) last observation at 17:49 U.T. on 1601+106 for HO last observation at 17:56 U.T. on 0552+398 for HH last observation at 18:02 U.T. on 0805+410 for AP-GC-MA-WF 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) 333 72828201 Fairbanks A GC 1 (TT) 354 40476601 HartRAO J HH 3 (HDT) 232 72326201 Hobart H HO 2 (HDT) 177 72425901 Matera I MA 3 (HDT) 313 72435701 Westford E WF 1 (TT) 363 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. 7) The source models were updated as of mid August 1997 by Dave Shaffer. Procedures ========== Please use the modified CDP Wide-band SX sequence, CDP-WBCA, for this experiment. Correlation ========== This experiment will be correlated at the Washington Correlator with all baselines being correlated. SKED Summary from file ./ca031.skd for experiment CA031 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I I 0 0 .0 0048-097Ix x x xx xx xx x x x x x x x x x I 18 36 5.9 0059+581I x x x x x x x x x x x x x x x x x xI 18 102 10.2 0104-408I x xx x xx x x x x I 10 14 4.5 0106+013I x x x x x xx xxI 9 9 1.4 0119+115I x x x x x x x x x xx x x I 13 33 4.2 0119+041Ix xI 2 2 .3 0208-512I x x x x x x I 6 6 2.5 0229+131Ix x x x x x xxI 8 21 2.7 0235+164I x x x I 3 3 .4 CTA26 Ix x x xx I 5 11 1.8 0402-362I x xx xxx x x x x x I 11 13 4.3 0454-234I x xxx xxx x xx xxx xI 14 27 5.9 0458-020Ix xx x x x xx x x x x I 12 16 2.5 0530-727I I 0 0 .0 0528+134Ix x x x x x x x xx x xxx xx xx xxx I 21 69 9.4 0537-441I I 0 0 .0 0552+398Ix x xx x x x x x xx x x x x xxx x xx xI 22 99 11.2 0556+238Ix x x x x xx xx xx x x xx I 15 38 4.2 0637-752I x x x x x x x x x x I 10 10 4.1 0718+793I x I 1 3 .3 0727-115I xx x x x x xxx x x x xx x x I 16 25 4.8 0749+540I x x x x x x x x xx x x xx x x x x I 18 93 9.4 0804+499I I 0 0 .0 0805+410I x x x x x x x xx xx x x x x x x x I 19 66 6.4 0823+033I x xx xx x xx x x xI 11 34 5.0 OJ287 I x x xx I 4 4 .5 0919-260I x x I 2 2 .8 0920-397I x I 1 1 .3 4C39.25 I x x x xx x x x x x x xx x xx x xx I 19 90 10.6 OK290 I xx x x x x I 6 12 1.3 0955+476I x x x x xx x x x xx x x x x x x xx xx I 21 90 10.5 1034-293Ix x x xx x x x x x I 10 12 2.5 1044+719I x x x x x x x x x x x xx x xx x x I 18 87 8.7 1053+815I I 0 0 .0 1057-797I x x x x x x x xI 8 8 3.3 1104-445I I 0 0 .0 1124-186I x x xx x x I 6 6 1.3 1128+385I x xx x x x x x xx x x x xx x xxx I 19 69 6.5 1144-379I x x x x x x xI 7 7 2.4 1219+044I x x x x I 4 10 1.4 1255-316I x I 1 1 .6 1300+580I I 0 0 .0 1308+326I x x x x x xx x x x x x xx x x x I 17 39 3.8 1313-333Ix x x x x x xI 7 7 2.0 1334-127Ix xx x x x x x x x xx x xI 14 16 3.2 1351-018I x x x x I 5 11 1.8 1357+769I x x x x x x x x x x x x x x x x I 16 87 8.7 1424-418I x xx x x x xI 7 7 2.4 1451-375I x x I 2 2 .7 1606+106Ix x x x x x x xxx xx xxx xx x I 18 48 6.3 1610-771Ix x x x xx x x x I 9 9 3.7 1622-253I xx x x x x I 6 6 1.9 NRAO512 I x xx x xx x x x x x x x x x x x xxI 19 90 10.6 1726+455I x x x x I 4 15 1.8 1739+522I x x xx x x x xx x x x x xxx x xI 18 91 9.7 1741-038Ix x x xxx x x x x x xxxxx xx xx xxx x I 24 62 10.0 1749+096I x x x x x x xx I 8 29 4.0 1815-553I x I 1 1 .4 1908-201I x xx xx x x xx x I 10 10 2.4 1921-293I x x xx xx xx x xx x x x x I 15 15 3.5 1954-388I x x xx x xx xx x I 10 10 3.4 1958-179I x xx x x x I 6 10 2.0 2005-489I I 0 0 .0 2052-474I I 0 0 .0 2121+053I x x I 2 2 .3 2128-123I x xx x x xx x x I 9 11 1.9 2134+00 I x x x x I 4 4 .6 2145+067Ix x xxx x xx x x xx x xx xx x xxI 20 43 5.9 2234+282I x x x x x I 5 16 1.6 2255-282I x xx x x I 5 5 1.4 Total scans, obs: 649 1775 Average number of obs. per baseline per source (normalized by up-time) = 3.7 Min = .0 Max = 26.4 (Baseline Hh-Ma on 0528+134) RMS = 5.9 Total time: 1444 minutes ( 24.1 hours). Key: Ap=ALGOPARK Gc=GILCREEK Hh=HARTRAO Ho=HOBART26 Ma=MATERA Wf=WESTFORD Ap Gc Hh Ho Ma Wf Avg % obs. time: 27 39 36 29 40 44 36 % cal. time: 3 4 2 2 3 4 3 % slew time: 54 20 44 24 18 13 29 % idle time: 14 35 15 43 38 36 30 # of tapes : 1.8 .7 2.2 1.8 2.4 .8 total # scans: 333 354 232 177 313 363 295 # scans/hour : 13 14 9 7 13 15 12.3 Avg scan (sec): 70 97 136 143 110 107 110 # OF OBSERVATIONS BY BASELINE | Ap Gc Hh Ho Ma Wf StnTotal -------------------------------------- Ap|333 249 28 5 156 320 608 Gc| 354 18 51 188 260 798 Hh| 232 123 124 36 328 Ho| 177 17 7 624 Ma| 313 193 815 Wf| 363 377 Number of 2-station scans: 339 Number of 3-station scans: 160 Number of 4-station scans: 136 Number of 5-station scans: 14 Number of 6-station scans: 0 Total # of scans, observations: 649 1775 Average baseline components for all observations Average XY = 4896. Average XZ = 4615. Average YZ = 3995. Average length = 5770.