CORE-B503 (Continuous Observations of the Rotation of the Earth-B503) 1999 April 21 Notes prepared by Cynthia Thomas and Nancy Vandenberg,NVI/GSFC Schedule name: CB503.SKD on CDDISA Nominal Start: 18:30 U.T. on April 21 (day 111) first observation at 18:30 U.T. on 4C39.25 for NT-GN-UR-YB first observation at 18:30 U.T. on 1908-201 for 45-KK-SH Nominal Stop: 18:30 U.T. on April 22 (day 112) last observation at 18:24 U.T. on OK290 for NT-GN-YB last observation at 18:24 U.T. on 1749+096 for KK-45 last observation at 18:27 U.T. on 1622-253 for SH-UR 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 DSS45 T 45 1 (TT) 133 16426001 Kokee K KK 1 (TT) 261 72983001 Noto S NT 2 (HDT) 186 75478901 NRAO 20M N GN 1 (TT) 225 72484701 Seshan C SH 3 (HDT) 218 72336101 Urumqi U UR 2 (HDT) 222 73303201 Yebes Y YB 2 (HDT) 151 73333601 Purpose ======= The purpose of the CORE-B sessions is to obtain EOP data on days adjacent to the main NEOS/CORE-A and CORE-3 sessions and thus extend the span of continuous data. The secondary purpose of CORE-B is to provide observing sessions during which the stations can demonstrate their performance and their ability to participate in future regular CORE sessions. During the period of January through September CORE-B is observed on Wednesdays starting at 18:30 UT, following a NEOS session. Beginning on October 1 CORE-B is observed on Thursdays starting at 19:00 UT, following the CORE-3 sessions. The CORE-B networks are numbered 4, 5, and 6 to distinguish them from the networks used in 1998. Schedule ======== This is a new schedule generated by C. Thomas with the automatic mode of sked. The characteristics of the CORE-B schedules have changed slightly. Changes were made to smooth out the distribution of observations over the sky. Following are the characteristics of the CORE-B schedule file: 1) This schedule was optimized for sky coverage. 2) Only the observations in the previous 2 hours of the schedule were considered for the minor options. The best 50% 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 thirty minutes. 5) The minimum SNR limits for the baselines were set to 20 for X-band and 15 for S-band. 6) This schedule was made using 54 sources which helped improve the sky coverage. Simulation Results ================== Simulated data from this schedule was used in a global solution to estimate the formal errors. The table below lists the formal errors for Earth orientation parameters. These results meet the simulation goals for the CORE-B network. Also shown in the table are the maximum correlations between the Earth orientation parameters and other parameters. ____________________________________________ | | | | | | EOP |Formal| Other | | |Parameters |Errors|Parameters|Correlation| |____________|______|_________ |___________| | | | | | |X-Wobble | 50.58| ------- | under 40% | | | | | | |Y-Wobble | 44.25| ------- | under 40% | | | | | | |UT1-TAI | 2.81| ------- | under 40% | | | | | | |UT1-TAI Rate| 5.03| ------- | under 40% | | | | | | ____________________________________________ 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 following databases: Date Experiment ==== ========== 98DEC15 NEOS-A294 98DEC15 CORE-A051 98DEC22 NEOS-A295 98DEC29 NEOS-A296 98DEC29 CORE-A052 99JAN05 NEOS-A297 99JAN19 NEOS-A299 Procedures ========== Please generate the procedures for this session using drudg. Correlation ========== This experiment will be correlated at the Haystack Correlator with all baselines being correlated. SKED Summary from file ./cb503.skd for experiment CB503 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0048-097Ixx xx xx x x x x x x x xx x x I 17 37 4.0 0059+581I x x x x x x x x x x x x x x x x xxI 18 197 15.9 0104-408Ixx x x x x x x I 8 11 1.2 0106+013Ix I 1 1 .1 0119+115I I 0 0 .0 0119+041I I 0 0 .0 0229+131I I 0 0 .0 0235+164I I 0 0 .0 CTA26 Ixx x x x xx x x x x x x x x x xx x xx I 21 64 6.6 0402-362I x xx x x x I 6 6 .7 0454-234Ix x x x x xx x x xx x x x x x xI 17 46 5.0 0458-020I x xI 2 6 .6 0528+134I x xx xx xx x x x x x x x x x x x x xx xx xxI 25 89 8.9 0552+398Ixx x x x x x x xx x x x x x x x x x x x x x I 23 134 12.5 0556+238I x I 1 1 .1 0718+793I I 0 0 .0 0727-115Ix xx x x x x xx x x x xx x x x x x xx x x xI 24 71 7.6 0804+499I x x x x x x x x I 8 72 6.8 0805+410I x I 1 3 .2 OJ287 I x x x x x xx x xx xI 11 41 4.1 0919-260I x I 1 0 .0 0920-397I x I 1 1 .1 4C39.25 I x x x xx x x x x x x xx x x x x x x x xI 21 121 10.5 OK290 I x x I 2 6 .5 0955+476I x x x x I 4 28 2.0 1034-293I x x x I 3 7 .8 1053+815Ix x x x x x x I 7 15 1.0 1124-186Ix x xx x x x x x x x x xx x I 15 43 4.7 1128+385I x x x I 3 23 2.8 1144-379I x x x x x x I 6 11 1.2 1219+044Ix x x x x xx x x x xI 11 23 2.3 1255-316I I 0 0 .0 1300+580I x I 1 1 .1 1308+326I x x x x x I 5 7 .9 1334-127Ix x x x xx x x x x I 10 17 1.8 1351-018I x x I 2 7 .7 1357+769I x x x x x x x x x x x I 11 160 10.7 1451-375I I 0 0 .0 1606+106I x x x x x x xxx x x x xI 13 27 2.7 1622-253I x x x x xx x x x x xx x x xx xI 17 45 5.1 1739+522I x x x x xx x x xx x x x x x x x x x x I 20 172 15.6 1741-038I x x x x xx x x xx xx x x x x x x xx xxx xI 24 81 8.4 1749+096Ix x x x x x x xx xxx x x x x I 16 85 8.7 1908-201I x x x x x x xxx x x x I 12 28 3.1 1921-293I x x x x I 4 5 .5 1954-388Ix x x x x x x x x I 9 20 1.9 1958-179I x x x I 3 9 1.0 2121+053Ix x x x x x x x x xx x x x xxx xx xI 20 64 6.4 2128-123I x x x I 3 4 .5 2134+00 I I 0 0 .0 2145+067I x x x x I 4 8 .8 2234+282I x x x x I 4 6 .6 3C454.3 I I 0 0 .0 2255-282Ix x I 2 3 .3 Total scans, obs: 437 1806 Average number of obs. per baseline per source (normalized by up-time) = 3.0 Min = .0 Max = 23.9 (Baseline 45-Sh on 1749+096) RMS = 5.0 Total time: 1439 minutes ( 24.0 hours). Key: 45=DSS45 Kk=KOKEE Nt=NOTO Gn=NRAO20 Sh=SESHAN25 Ur=URUMQI Yb=YEBES 45 Kk Nt Gn Sh Ur Yb Avg % obs. time: 12 32 24 32 32 30 21 26 % cal. time: 1 3 2 2 2 2 1 2 % slew time: 30 15 31 13 47 26 17 26 % idle time: 55 49 41 51 16 39 58 44 # of tapes : .3 .5 1.5 .5 2.1 1.9 1.3 total # scans: 133 261 186 225 218 222 151 199 # scans/hour : 5 10 7 9 9 9 6 8.3 Avg scan (sec): 84 108 113 124 130 119 125 114 # OF OBSERVATIONS BY BASELINE | 45 Kk Nt Gn Sh Ur Yb StnTotal ------------------------------------------ 45|133 98 17 21 98 76 0 362 Kk| 261 44 143 132 104 46 531 Nt| 186 117 82 123 137 368 Gn| 225 59 76 116 581 Sh| 218 180 51 611 Ur| 222 86 591 Yb| 151 568 Number of 2-station scans: 112 Number of 3-station scans: 157 Number of 4-station scans: 98 Number of 5-station scans: 41 Number of 6-station scans: 15 Number of 7-station scans: 0 Total # of scans, observations: 437 1806 Average baseline components for all observations Average XY = 6342. Average XZ = 5081. Average YZ = 5074. Average length = 7067.