CORE-B502 (Continuous Observations of the Rotation of the Earth-B502) 1999 April 7 Notes prepared by Cynthia Thomas and Nancy Vandenberg,NVI/GSFC Schedule name: CB502.SKD on CDDISA Nominal Start: 18:30 U.T. on April 7 (day 097) first observation at 18:30 U.T. on 1622-253 for 45-KK-SH-UR first observation at 18:30 U.T. on 1357+769 for NT-GN-YB Nominal Stop: 18:30 U.T. on April 8 (day 098) last observation at 16:23 U.T. on 1334-127 for 45 last observation at 18:22 U.T. on 0235+164 for YB last observation at 18:26 U.T. on 1739+522 for KK-NT-GN-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) 179 16426001 Kokee K KK 1 (TT) 254 72983001 Noto S NT 2 (HDT) 193 75478901 NRAO 20M N GN 1 (TT) 232 72484701 Seshan C SH 3 (HDT) 214 72336101 Urumqi U UR 3 (HDT) 219 73303201 Yebes Y YB 2 (HDT) 143 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 61 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 | 51.56| ------- | under 40% | | | | | | |Y-Wobble | 46.50| ------- | under 40% | | | | | | |UT1-TAI | 2.88| ------- | under 40% | | | | | | |UT1-TAI Rate| 5.38| ------- | 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 ./cb502.skd for experiment CB502 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I xx x x x x x I 7 17 1.7 0048-097I xx x xx x x x x x I 10 52 5.4 0059+581I xx x x x x x x x xx x x x x x I 16 164 13.3 0104-408Ix x x x x x x I 7 13 1.2 0106+013I I 0 0 .0 0119+115I I 0 0 .0 0119+041I I 0 0 .0 0229+131I I 0 0 .0 0235+164I xx xx x x x x x x x x x x xx x x xx xI 21 99 9.9 CTA26 Ix xx xx x x x x x x x x x x x x xx I 19 60 6.2 0402-362I x x x x x x I 6 12 1.1 0454-234I x x x x x x x x x x x xx xI 14 45 4.8 0458-020I x x x x I 4 10 1.0 0528+134I x x x xx x x x x x x xx x x xx xx xI 20 73 7.4 0552+398Ix x x x x x x x x x x x x x x x x x x I 19 126 12.0 0556+238I x I 1 1 .1 0718+793I I 0 0 .0 0727-115Ixx x x x x x x x x x x x x x x xx x I 19 64 6.8 0749+540Ix x x x x x I 6 42 3.7 0804+499I x x x x x x I 6 30 2.9 0805+410I x x x x I 4 20 2.1 0823+033I x x x xx I 5 14 1.4 OJ287 I x x x x x x x x x x x I 11 45 4.8 0919-260I I 0 0 .0 0920-397I I 0 0 .0 4C39.25 Ix x x xx x x x x x x x x I 13 91 8.4 OK290 I x I 1 3 .3 0955+476I x x I 2 12 .8 1034-293I x x x I 3 5 .6 1044+719I x x x x x x x x I 8 69 4.9 1053+815I x x I 2 2 .1 1124-186Ix x x x x x x x x x x xx I 13 41 4.4 1128+385I x I 1 10 1.3 1144-379I x x x x I 4 10 1.0 1219+044I x x x x x x I 6 12 1.2 1255-316I I 0 0 .0 1300+580I x I 1 3 .3 1308+326I x x x x x I 5 7 .9 1313-333I x x I 2 2 .2 1334-127I x x x x x x x x x x x I 11 24 2.7 1351-018I x x x I 3 10 1.0 1357+769I x x x x x x x xx x xI 11 143 9.5 1451-375I I 0 0 .0 1606+106I x x x x x x xx x x x I 11 27 2.7 1622-253Ixx x x x x x x x x x x x x xx I 16 44 4.7 NRAO512 I x x x x x x x x x x x x x x x x x xI 18 117 10.5 1726+455I I 0 0 .0 1739+522Ix x x x x x x x x x x x x xx x x x I 18 165 15.1 1741-038I x x x x x x xx xx x x xx x xx xI 18 66 6.8 1749+096Ix x x x x x x xx x xx x xx I 15 67 6.7 1908-201Ix x x x x x x x I 8 21 2.2 1921-293I x x x x x I 5 12 1.3 1954-388I x x x x x xI 6 14 1.3 1958-179I x I 1 3 .3 2121+053Ix xx x x x x x x x x xx x x x xx x I 19 71 7.2 2128-123I x x x x x x I 6 10 1.1 2134+00 I I 0 0 .0 2145+067I I 0 0 .0 2234+282I I 0 0 .0 3C454.3 I I 0 0 .0 2255-282I x I 1 3 .3 Total scans, obs: 423 1951 Average number of obs. per baseline per source (normalized by up-time) = 2.9 Min = .0 Max = 23.1 (Baseline 45-Sh on 0235+164) RMS = 4.6 Total time: 1438 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: 17 33 29 33 34 32 22 29 % cal. time: 2 2 2 2 2 2 1 2 % slew time: 25 14 31 12 45 25 17 24 % idle time: 54 48 37 50 17 38 58 43 # of tapes : .3 .6 1.8 .6 2.2 2.1 1.4 total # scans: 179 254 193 232 214 219 143 204 # scans/hour : 7 10 8 9 8 9 5 8.5 Avg scan (sec): 85 114 129 126 140 129 136 122 # OF OBSERVATIONS BY BASELINE | 45 Kk Nt Gn Sh Ur Yb StnTotal ------------------------------------------ 45|179 126 31 32 125 98 1 447 Kk| 254 51 150 128 107 46 614 Nt| 193 124 89 125 133 392 Gn| 232 68 84 111 639 Sh| 214 183 55 624 Ur| 219 84 601 Yb| 143 585 Number of 2-station scans: 98 Number of 3-station scans: 137 Number of 4-station scans: 127 Number of 5-station scans: 47 Number of 6-station scans: 14 Number of 7-station scans: 0 Total # of scans, observations: 423 1951 Average baseline components for all observations Average XY = 6370. Average XZ = 5279. Average YZ = 5255. Average length = 7237.