CORE-A048 (Continuous Observations of the Rotation of the Earth-A048) 1998 November 3 Notes prepared by Cynthia Thomas, NVI/GSFC Schedule name: CA048.SKD on CDDISA Nominal Start: 18:00 U.T. on November 3 (day 307) first observation at 18:00 U.T. on 0528+134 for GC-HO first observation at 18:00 U.T. on 1749+096 for AP-HH-MA-WF Nominal Stop: 18:00 U.T. on November 4 (day 308) last observation at 17:49 U.T. on 0208-512 for HH-Ho last observation at 17:51 U.T. on 1606+106 for GC-MA last observation at 17:56 U.T. on 1622-253 for AP-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) 312 72828201 Fairbanks A GC 1 (TT) 329 40476601 HartRAO J HH 3 (HDT) 224 72326201 Hobart H HO 2 (HDT) 167 72425901 Matera I MA 3 (HDT) 303 72435701 Westford E WF 1 (TT) 346 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. 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 ./ca048.skd for experiment CA048 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I xx x x I 4 8 1.4 0048-097I xx x xx x x x x I 9 13 2.2 0059+581I x x x x x x x x x x x x xx x x x x xI 19 108 10.8 0104-408I x xx x xxx x x x I 10 14 4.4 0106+013I x x x x I 4 4 .6 0119+115I x x x x x x xx x x xx x I 13 27 3.5 0119+041I x x I 2 6 .9 0208-512I x x x x x x x I 7 7 2.9 0229+131I x x x x x x x x xx I 10 26 3.4 0235+164I x xI 2 2 .3 CTA26 I x x x x x x I 6 14 2.3 0402-362Ix x x xx xx x xI 9 9 3.1 0454-234Ixx x xx x x x xx xxxx xx I 16 28 5.9 0458-020Ix x x x x I 5 9 1.4 0530-727I I 0 0 .0 0528+134Ixx x x x x x x x x x x xx xxx x x I 20 51 6.8 0537-441I x I 1 1 .3 0552+398I xx x xx x xx x x x x x xx x xx xx xxI 22 97 11.0 0556+238I x x I 2 6 .7 0637-752I x x x x x x x x x xI 10 10 4.1 0718+793I x xI 2 6 .6 0727-115I xxx x x xxx x x x x x x xxx xxx xxI 22 37 7.5 0749+540Ix x x x x x x x xx x x xI 13 72 7.3 0804+499I xx x x x x x x x x x I 11 53 5.9 0805+410I x x x xx x xI 7 13 1.2 0823+033I x x x x xx x I 7 19 2.8 OJ287 I x x x x I 4 4 .5 0919-260I x x x x I 4 4 1.6 0920-397I x I 1 1 .3 4C39.25 Ixxx x x x xx xx x x x x x x xx x x x x I 22 106 11.1 OK290 I xx x x x x x I 7 13 1.4 0955+476I xx x x xx x x x x x x x xx x x x x I 19 76 8.8 1034-293Ix x x x x x x xx I 9 9 3.0 1044+719I x xx x x x x x x x x x x x x x x xI 18 99 9.9 1053+815I I 0 0 .0 1057-797I x x x x x x x x I 8 8 3.3 1104-445I I 0 0 .0 1124-186I xx x x x x x x I 8 8 1.7 1128+385I x xx x x x x x x I 9 20 1.7 1144-379I x xx xx x x I 7 7 2.4 1219+044I x x x I 3 7 1.0 1255-316I x x I 2 2 1.3 1300+580I x I 1 3 .3 1308+326I x x x x x x x x x xI 10 16 1.5 1313-333I x x xx x x x x x I 9 9 1.7 1334-127I x I 1 1 .2 1351-018I x x x I 3 5 .8 1357+769I x x x x x x x x x x x x x x x x x I 17 96 9.6 1424-418I x x x x x I 5 5 1.7 1451-375I x x x I 3 3 1.0 1606+106Ixx xx xxx x x x xx x xx x I 16 33 4.3 1610-771I x x x x x x x x x I 9 9 3.7 1622-253I x xx xx x I 6 6 1.9 NRAO512 Ix x xx x xx xx xx x x x x x x x I 18 79 9.2 1726+455Ix x x x x x I 6 14 1.6 1739+522I xx x x x xxx x xx x x x x x xx x xx xI 22 112 11.9 1741-038Ixxxx x xx x xxx x xxxxx x x x xxxx x I 25 61 9.8 1749+096Ixx x x x x xx x xxx xxxx x I 17 58 8.1 1815-553I x I 1 1 .4 1908-201Ixx x x x x xx x xx I 11 11 2.9 1921-293Ix x xx x x x x xx xx x xx x I 16 16 4.0 1954-388I x x x x x x xx x I 9 9 3.1 1958-179I xx x x x x x I 7 9 1.8 2005-489I I 0 0 .0 2052-474I I 0 0 .0 2121+053I x xx xx x x x x x x x I 12 25 3.5 2128-123I x x x x x x x x x I 9 11 1.9 2134+00 I x x x x x I 5 5 .8 2145+067I x x x x xx xx x x x x I 12 23 3.2 2234+282I x x x x x xx x xx I 10 35 3.6 2255-282I x xx x x x I 6 6 2.1 Total scans, obs: 620 1665 Average number of obs. per baseline per source (normalized by up-time) = 3.4 Min = .0 Max = 38.1 (Baseline Gc-Ho on 0727-115) RMS = 5.8 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 42 37 30 41 43 36 % cal. time: 3 3 2 1 3 4 3 % slew time: 57 20 44 23 17 13 29 % idle time: 13 33 14 43 37 38 30 # of tapes : 1.7 .7 2.3 1.8 2.5 .8 total # scans: 312 329 224 167 303 346 280 # scans/hour : 13 13 9 6 12 14 11.7 Avg scan (sec): 70 111 144 155 119 108 117 # OF OBSERVATIONS BY BASELINE | Ap Gc Hh Ho Ma Wf StnTotal -------------------------------------- Ap|312 227 21 6 145 302 561 Gc| 329 19 47 182 242 750 Hh| 224 116 121 33 304 Ho| 167 16 6 588 Ma| 303 182 769 Wf| 346 358 Number of 2-station scans: 331 Number of 3-station scans: 148 Number of 4-station scans: 130 Number of 5-station scans: 11 Number of 6-station scans: 0 Total # of scans, observations: 620 1665 Average baseline components for all observations Average XY = 4888. Average XZ = 4627. Average YZ = 3985. Average length = 5771.