CORE-A030 (Continuous Observations of the Rotation of the Earth-A030) 1998 February 24 Notes prepared by Cynthia Thomas, NVI/GSFC Schedule name: CA030.SKD on CDDIS Nominal Start: 18:00 U.T. on February 24 (day 055) first observation at 18:00 U.T. on 4C39.25 for GC-HH-MA first observation at 18:00 U.T. on 1958-179 for AP-HO-WF Duration: 24 hours Nominal Stop: 18:00 U.T. on February 25 (day 056) last observation at 17:53 U.T. on 0749+540 for AP-WF last observation at 17:57 U.T. on 0454-234 for GC-HO last observation at 18:00 U.T. on 0402-362 for HH-MA 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) 323 72828201 Fairbanks A GC 1 (TT) 345 40476601 HartRAO J HH 3 (HDT) 222 72326201 Hobart H HO 2 (HDT) 175 72425901 Matera I MA 3 (HDT) 311 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 ./ca030.skd.auto for experiment CA030 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I xx x x x x xx x xI 10 16 2.6 0048-097Ix x x x x x x x x xx x x x I 14 34 6.7 0059+581I x x x xx x xx x x x x x x x x x x xI 20 108 10.8 0104-408I x xx x xx x xx x I 10 14 4.6 0106+013Ix x xx x x x x I 8 8 1.2 0119+115Ix x xx xx xx x x x I 11 29 3.6 0119+041Ix x I 2 6 .9 0208-512I x x x x x x I 6 6 2.5 0229+131I x x xx x x I 6 12 1.6 0235+164I x I 1 1 .1 CTA26 Ix x x x x xxx I 8 16 2.6 0402-362I x x x xx x x x I 9 11 3.7 0454-234Ix x xx xxx x xxx x x x I 14 20 4.1 0458-020Ix x xx xx x x x x xx x I 13 21 3.3 0530-727I I 0 0 .0 0528+134I x x x x x x x xx xx xx xx x x xx xI 20 58 7.9 0537-441I I 0 0 .0 0552+398I xx x x x x x x xx x x xx xx x x x I 19 76 8.6 0556+238Ix x x x x xx xx xx x I 12 35 3.7 0637-752I x x x x xx x x x I 9 9 3.7 0718+793I I 0 0 .0 0727-115I x x x x xx x x xx x x x x x x I 16 25 5.3 0749+540I x x x x x x x x x x x x xx x x x I 17 93 9.4 0804+499I x x I 2 4 .4 0805+410I x x x x x x x x x x x x xx x x x I 17 57 5.5 0823+033I x x x x xx x x x x I 10 29 4.2 OJ287 I x x I 2 2 .2 0919-260I x x I 2 2 .8 0920-397I x I 1 1 .3 4C39.25 I x xx x x x x xx xx x xx x x x xx xI 20 93 9.7 OK290 I x x x x x xx x I 8 18 1.9 0955+476I x x x xx x x x x x x x x x x x x xx xx xI 22 86 10.0 1034-293Ixx x x xx xx x x x x I 12 16 3.5 1044+719I x x x x x x x x x x x x x x x x x x xI 19 93 9.3 1053+815I I 0 0 .0 1057-797Ix x x x x x x x I 8 8 3.3 1104-445I I 0 0 .0 1124-186Ix x x x x x x I 7 9 1.8 1128+385I x x x x x x xx x xx x xx x x I 16 60 5.5 1144-379Ix x x x x x I 6 6 2.0 1219+044I x x I 2 4 .6 1255-316I I 0 0 .0 1300+580I x x I 2 6 .6 1308+326I xx x x x x xx x x x xx x I 14 32 3.1 1313-333Ix x x x x I 5 5 1.7 1334-127Ix x x x x x x xx x x x I 12 14 2.3 1351-018I x xx x x I 5 11 1.8 1357+769I x x x x x x x x x x x x x xx x x x xI 19 93 9.3 1424-418I x x x x xI 5 5 1.7 1451-375I x x I 2 2 .7 1606+106I x x xx x x x x x xx xx xx x xx x x x I 21 52 6.8 1610-771I x x x x x x x xI 8 8 3.3 1622-253I x xx x x I 5 5 1.5 NRAO512 Ix x x xx x x x x x x xx x x xx x x xI 20 90 10.4 1726+455I x I 1 3 .4 1739+522I xx x x x x x x x x x x x x x xx x x xI 20 103 10.9 1741-038I x xx x x x xx x x x xx xx x x xx x x I 21 50 8.0 1749+096I x x x x x xx xx x xx I 12 40 5.5 1815-553I x x I 2 2 .8 1908-201I x x xx x x x xx I 10 10 2.5 1921-293I xx xx xx xx xx xxx x xx x I 17 19 4.8 1954-388I x x xx xx xx x x I 10 10 3.4 1958-179I xx xx x x x I 7 11 2.4 2005-489I I 0 0 .0 2052-474I I 0 0 .0 2121+053I I 0 0 .0 2128-123I xx x xx x x x x I 9 13 2.3 2134+00 I x x x x x I 5 5 .8 2145+067Ix x x xx xx x x x x x x x x I 15 33 4.6 2234+282I x x xI 3 7 .7 2255-282I x x x x x xx x I 8 14 3.3 Total scans, obs: 637 1729 Average number of obs. per baseline per source (normalized by up-time) = 3.6 Min = .0 Max = 28.6 (Baseline Gc-Ho on 0727-115) RMS = 5.7 Total time: 1441 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: 26 39 34 30 40 44 35 % cal. time: 3 3 2 2 3 4 3 % slew time: 53 20 44 25 18 13 29 % idle time: 15 36 18 42 38 37 31 # of tapes : 1.7 .7 2.1 1.8 2.4 .8 total # scans: 323 345 222 175 311 363 289 # scans/hour : 13 14 9 7 12 15 12.1 Avg scan (sec): 70 99 135 148 112 106 111 # OF OBSERVATIONS BY BASELINE | Ap Gc Hh Ho Ma Wf StnTotal -------------------------------------- Ap|323 239 23 9 147 312 575 Gc| 345 18 50 185 257 779 Hh| 222 118 116 34 326 Ho| 175 19 9 604 Ma| 311 193 803 Wf| 363 371 Number of 2-station scans: 324 Number of 3-station scans: 171 Number of 4-station scans: 132 Number of 5-station scans: 10 Number of 6-station scans: 0 Total # of scans, observations: 637 1729 Average baseline components for all observations Average XY = 4914. Average XZ = 4628. Average YZ = 4005. Average length = 5784.