CORE-B111 (Continuous Observations of the Rotation of the Earth-B111) 1998 August 26 Notes prepared by Cynthia Thomas, NVI/GSFC Schedule name: CB111.SKD on CDDIS Nominal Start: 18:30 U.T. on August 26 (day 238) first observation at 18:30 U.T. on 4C39.25 for AP-YK-FT-GC- KA-ON-WZ first observation at 19:03 U.T. on 0955+476 for 15 Duration: 24 hours Nominal Stop: 18:30 U.T. on August 27 (day 239) last observation at 18:21 U.T. on 0727-115 for YK last observation at 18:27 U.T. on 0454-234 for 15 last observation at 18:29 U.T. on 0458-020 for GC-KA last observation at 18:30 U.T. on 1606+106 for AP-FT-ON-WZ Correlator: Haystack **Frequency Sequence**: CDPSX - Standard CDP SX sequence. (360 MHz wide at X, 85 MHz wide at S) 1 letter 2 letter Station Code Code # of tapes # of obs Occupation Code Algonquin G AP 2 (HDT) 249 72828201 Yellowknife X YK 2 (HDT) 125 72965101 DSS15 D 15 1 (TT) 279 72318701 Fortaleza F FT 2 (HDT) 133 72974801 Fairbanks A GC 1 (TT) 285 40476601 Kashima-26 Q KA 3 (HDT) 191 18567601 Onsala T ON 3 (HDT) 190 72137701 Wettzell V WZ 3 (HDT) 254 72247801 Purpose ======= The purpose of the CORE-B sessions is to provide additional data for comparison of EOP measurements and to obtain long 48-hour data sets for geophysical studies. The analysis of CORE-A and CORE-B has concentrated on comparing the EOP results from these sessions with the NEOS sessions. Preliminary results of the comparisons show that, while the EOP results generally agree between different networks, there are systematic differences that are not fully understood. Because of these discrepancies, it was decided that an improved comparison could be made if the CORE-A, NEOS, and CORE-B could all be compared for the same day, making possible a 3-way comparison. Therefore we will run the CORE-B sessions on days adjacent to the CORE-A/NEOS days instead of on the alternate week. This plan will concentrate the observing days but it will provide more a robust data set for understanding the differences. 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 two hours of the schedule were considered for the minor options. The best 60% 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 all baselines were set to 20 for X-band and 15 for S-band. 6) This schedule was made using 50 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 98Mar03 NEOS-A253 and the 98JAN27XA CORE-A028 experiments. Procedures ========== There are no special procedures for this experiment. Please use your standard SGP procedures. Correlation ========== This experiment will be correlated at the Haystack Correlator with all baselines being correlated. SKED Summary from file ./cb111.skd for experiment CB111 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I x x x xx x x x I 8 23 2.1 0048-097I x xx x x xx x x I 9 19 1.9 0059+581I x x x x x x x x xx x x x x x xI 16 328 13.3 0106+013Ix xx x xx x x xxx x x x x x x xx xI 20 20 1.6 0119+115Ix xx x xx x x xx xx x x I 14 35 2.4 0119+041I x x x x xx I 6 15 1.1 0229+131I x x I 2 2 .1 0235+164I x x I 2 4 .3 CTA26 I x x x x x x xx xx x x I 12 27 2.3 0454-234I x x x x x x x x x I 9 17 3.0 0458-020I x x x x x x xx x I 9 15 1.2 0528+134Ix xx x xx x x x xx xx xI 14 34 2.3 0552+398I xx x x x x x x x xx x x x x xx x xx x x xx I 24 373 17.5 0556+238I xx x x x x xx I 8 32 1.9 0718+793Ix x x x x x x x x x I 10 28 1.0 0727-115I xx xxx x x x x x x x x x x x x I 17 64 6.9 0749+540I x x x x x x x x I 8 133 5.6 0804+499I x x x x I 4 46 2.0 0805+410I x x x I 3 15 .7 0823+033I x x x x x xx x x xxI 11 32 2.5 OJ287 I xx x x xx x xxI 9 17 1.1 0919-260I x x x x x I 5 5 1.2 4C39.25 Ixxx x x x x x x x x x x x xx xxx x x x I 22 355 17.1 OK290 I xx x x xxx x x x x I 11 21 1.3 0955+476I x I 1 15 .7 1044+719I x x x x xI 5 60 2.4 1053+815I x I 1 3 .1 1124-186Ix x x x xx x x x x x x I 12 18 2.2 1128+385I x I 1 6 .3 1219+044Ix xx x xx xx x x x x x x x I 15 39 3.0 1300+580Ix x x I 3 18 .7 1308+326Ix xx x x x x x x x x x I 12 31 1.7 1334-127Ix x x x x x x x x x x x xx I 14 41 4.3 1351-018I x x x I 3 5 .4 1357+769Ix x x x x x x I 7 86 3.1 1606+106I x xx x x x x xxx x x x x I 15 76 5.4 1622-253I x x x xx xx x x x I 10 14 2.4 NRAO512 I x xx I 3 45 2.4 1726+455I x x x x I 4 41 1.9 1739+522I x x x x x x x x x x x x xI 13 263 11.1 1741-038I xxx xx x x xx x x x xx xxx x x x xxx I 23 133 11.3 1749+096I x x x x x xx x I 8 31 2.1 1908-201I xx x x x xx x xI 9 21 2.9 1958-179I x xx x x I 5 5 .5 2121+053I x x x x xx x x x x I 10 22 1.7 2128-123I xx x x x x x x x x x I 11 23 2.5 2134+00 I x x x xx x x x x xx xxx xx xI 17 17 1.3 2145+067Ix x x x xx x x xx xx x x x I 15 86 6.3 2234+282I x x x x x x x x xI 9 38 2.2 2255-282I x x x x x I 6 12 2.8 Total scans, obs: 485 2809 Average number of obs. per baseline per source (normalized by up-time) = 3.4 Min = .0 Max = 29.6 (Baseline On-Wz on 0727-115) RMS = 5.6 Total time: 1441 minutes ( 24.0 hours). Key: Ap=ALGOPARK Yk=ARIES_9M 15=DSS15 Ft=FORTLEZA Gc=GILCREEK Ka=KASHIMA On=ONSALA60 Wz=WETTZELL Ap Yk 15 Ft Gc Ka On Wz Avg % obs. time: 22 28 29 32 35 38 38 38 32 % cal. time: 2 1 3 1 3 2 2 2 2 % slew time: 54 21 39 25 19 20 15 10 25 % idle time: 20 49 28 40 41 38 44 47 38 # of tapes : 1.4 1.8 .5 2.0 .6 2.3 2.3 2.3 total # scans: 249 125 279 133 285 191 190 254 213 # scans/hour : 10 5 11 5 11 7 7 10 8.9 Avg scan (sec): 76 197 91 212 106 175 174 132 145 # OF OBSERVATIONS BY BASELINE | Ap Yk 15 Ft Gc Ka On Wz StnTotal ---------------------------------------------- Ap|249 77 207 90 169 70 87 118 846 Yk| 125 92 38 112 72 80 70 653 15| 279 77 212 116 86 98 692 Ft| 133 41 10 66 87 674 Gc| 285 158 102 118 669 Ka| 191 87 91 668 On| 190 178 595 Wz| 254 821 Number of 2-station scans: 172 Number of 3-station scans: 138 Number of 4-station scans: 56 Number of 5-station scans: 37 Number of 6-station scans: 40 Number of 7-station scans: 37 Number of 8-station scans: 5 Total # of scans, observations: 485 2809 Average baseline components for all observations Average XY = 5167. Average XZ = 4175. Average YZ = 3932. Average length = 5630.