CORE-B501 (Continuous Observations of the Rotation of the Earth-B501) 1999 January 27 Notes prepared by Cynthia Thomas and Nancy Vandenberg,NVI/GSFC Schedule name: CB501.SKD on CDDISA Nominal Start: 18:30 U.T. on January 27 (day 027) first observation at 18:30 U.T. on 1357+769 Nominal Stop: 18:30 U.T. on January 28 (day 028) last observation at 18:26 U.T. on 1739+522 for KK last observation at 18:22 U.T. on 0528+134 for SH last observation at 18:26 U.T. on 0235+164 for NT-GN-UR-YB 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 Kokee K KK 1 (TT) 234 72983001 Noto S NT 2 (HDT) 192 75478901 NRAO 20M N GN 1 (TT) 244 72484701 Seshan C SH 2 (HDT) 191 72336101 Urumqi U UR 3 (HDT) 215 73303201 Yebes Y YB 2 (HDT) 158 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 first half of the year CORE-B is observed on Wednesdays starting at 18:30 UT, following a NEOS session. Beginning on July 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 | 76.26| ------- | under 40% | | | | | | |Y-Wobble | 84.24| ------- | under 40% | | | | | | |UT1-TAI | 2.84|X Velocity| 41% | | | | | | |UT1-TAI Rate| 5.85| ------- | 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 ==== ========== 98SEP22 CORE-A045 98SEP29 NEOS-A283 98OCT06 NEOS-A284 98OCT06 CORE-A046 98OCT20 NEOS-A286 98OCT20 CORE-A047 98NOV03 NEOS-A288 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 ./cb501.skd for experiment CB501 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066Ix x xx x x x x x x x x x I 13 23 3.5 0048-097I x x x I 3 9 1.4 0059+581I x x x x x x x x x x x xx x x xxI 17 179 14.4 0104-408I x xI 2 2 .4 0106+013I I 0 0 .0 0119+115I x x x x x xx xI 8 24 3.2 0119+041I x x I 2 2 .3 0229+131I I 0 0 .0 0235+164Ix x x x x x x x x x I 10 30 3.8 CTA26 Ix x x x x x x x x x x x x x I 14 32 4.7 0402-362I x x x x x I 5 5 1.0 0454-234I x x x x x x xx x x x x x x x I 15 29 5.2 0458-020I x x x I 3 3 .4 0528+134I x x xx x x x x x x xx xx x x x xx x x x I 22 61 8.0 0552+398I xx x x x x xx x x xx x x x x x x x x x xI 22 114 12.1 0556+238I I 0 0 .0 0718+793I I 0 0 .0 0727-115I x x x x x x x x x x x x x x x x I 16 35 5.5 0749+540I x x x x x x x I 7 66 5.8 0804+499I x x x x x x x x xI 9 67 6.3 0805+410I I 0 0 .0 0823+033I I 0 0 .0 OJ287 I x x x x x I 5 9 1.1 0919-260I I 0 0 .0 0920-397I x I 1 1 .2 4C39.25 Ix x x x x x x x x x x x x x x x x x x I 19 109 11.7 OK290 I I 0 0 .0 0955+476I x x I 2 13 1.3 1034-293I x x x I 3 5 1.0 1044+719I x x x x x x x x x I 9 95 6.6 1053+815I x x x x I 4 8 .5 1124-186Ix xx x x x x x I 8 21 3.6 1128+385I x I 1 1 .1 1144-379I x x x I 3 3 .6 1219+044I x x x x x x xx x I 9 17 2.4 1255-316I I 0 0 .0 1300+580I x x x I 3 14 1.2 1308+326I x x I 2 4 .5 1313-333I I 0 0 .0 1334-127Ix x x x x x x x x x x x I 12 22 3.5 1351-018I x x I 2 2 .3 1357+769I x x x x x x x x x x I 10 145 9.7 1451-375I I 0 0 .0 1606+106I x x x I 3 3 .4 1622-253I x x x x x x x x x x x x I 12 20 3.6 NRAO512 I x x x x x x x x x x x x x x x x x x x x xxI 22 113 12.1 1726+455I I 0 0 .0 1739+522I x x x x x x x x x x x x x x x x I 16 133 12.1 1741-038Ixx x x xx x x x xx x x x x x x xx x I 20 47 6.9 1749+096Ix x x xx xx x x x xx x x xx xx x I 19 59 7.9 1908-201I x xx x x x x x x I 9 15 2.5 1921-293Ix xx x x x x I 7 9 1.7 1954-388I x x I 2 2 .4 1958-179I I 0 0 .0 2121+053I x x x x x x I 6 10 1.4 2128-123I I 0 0 .0 2134+00 I x I 1 1 .1 2145+067I x x xx x x x x I 8 12 1.6 2234+282I x x x x x I 5 11 1.3 3C454.3 I I 0 0 .0 2255-282I I 0 0 .0 Total scans, obs: 391 1585 Average number of obs. per baseline per source (normalized by up-time) = 2.8 Min = .0 Max = 22.5 (Baseline Sh-Ur on NRAO512 ) RMS = 4.5 Total time: 1437 minutes ( 24.0 hours). Key: Kk=KOKEE Nt=NOTO Gn=NRAO20 Sh=SESHAN25 Ur=URUMQI Yb=YEBES Kk Nt Gn Sh Ur Yb Avg % obs. time: 35 27 34 31 34 27 31 % cal. time: 2 2 2 2 2 1 2 % slew time: 13 34 14 39 25 21 24 % idle time: 47 35 48 26 37 49 40 # of tapes : .6 1.7 .6 2.0 2.2 1.8 total # scans: 234 192 244 191 215 158 205 # scans/hour : 9 8 10 7 8 6 8.6 Avg scan (sec): 131 125 120 142 136 152 134 # OF OBSERVATIONS BY BASELINE | Kk Nt Gn Sh Ur Yb StnTotal -------------------------------------- Kk|234 55 163 118 105 58 497 Nt| 192 124 85 133 142 482 Gn| 244 65 89 118 713 Sh| 191 166 64 416 Ur| 215 100 525 Yb| 158 537 Number of 2-station scans: 139 Number of 3-station scans: 127 Number of 4-station scans: 65 Number of 5-station scans: 45 Number of 6-station scans: 15 Total # of scans, observations: 391 1585 Average baseline components for all observations Average XY = 6808. Average XZ = 4649. Average YZ = 4524. Average length = 6881.