CORE-3002 (Continuous Observations of the Rotation of the Earth-3002) 2000 August 23 Notes prepared by Nancy Vandenberg and Cynthia Thomas,NVI/GSFC Schedule name: aug00/c3002.skd on CDDISA Nominal Start: 18:30 U.T. on August 23 (day 236) first observation at 18:30 U.T. on 0749+540 Nominal Stop: 18:30 U.T. on August 24 (day 237) last observation at 18:14 U.T. on 2145+067 for MA-WZ last observation at 18:17 U.T. on 0552+398 for GC-KK-ON-WF plus 3 test scans for GC-KK-WF until 18:33 Observing Mode: 2F (with barrel roll, see details below) 22 (Mk4 format with barrel roll, for GC-KK-WF) Correlator: Haystack 1 letter 2 letter Station Code Code # of tapes # of obs Occupation Code Fairbanks A Gc 2 (TT) 339 40476601 Kokee K Kk 2 (TT) 281 72983001 Matera I Ma 2 (TT) 327 72435701 Onsala T On 2 (TT) 313 72137701 Westford E Wf 2 (TT) 304 72097301 Wettzell V Wz 2 (TT) 350 72247801 Purpose ======= The CORE-3 sessions mark the start of the regular CORE oberving program. These sessions will provide a monthly 72-hour continuous data set from July through December (CORE-1 + NEOS + CORE-3). There are three additional CORE-3s scheduled during October and November which also will provide at least 48 hours of continuous data. CORE-3 sessions will be recorded in a Mark 4 mode which requires that the participating stations have Mark 4 capability. Observing Mode ============== This is the first CORE session that uses a "Mark 4" style observing mode. The mode for CORE-3 uses fan-out and records on all 32 tracks to achieve a data rate of 128 Mb/s, more than twice that of the standard geodetic Mode C which is 56 Mb/s. CORE Mode "2F" (twice the standard mode C, fanned out) ----------------------------------------------------------------- Number of frequencies 14 (standard wide-band frequency sequence modified to avoid RFI at Matera) Number of channels 16 (14 USB + 2 LSB) Channel bandwidth 4.0 MHz Sample rate 8 Mb/s Bits per sample 1 Total data rate 128 Mb/s Data rate on tape 4 Mb/s/track Fan-out 1:2 Tape speed 80 ips Tracks per pass 32 Passes per tape 14 Barrel roll yes (*) Track frame format Mark4 and VLBA (*) The 16 recorded channels are comprised of the standard 14-channel USB frequency sequence plus the LSB channels of the first and last frequencies at X-band. The two outer X-band LSB channels give extra sensitivity. They also slightly narrow the peak of the delay resolution function, resulting in better group delay precision. The stations with VLBA backends, Fairbanks and Kokee, will use barrel roll during this session (see below). Stations with Mark 4 formatters cannot barrel roll. (*) Special Instructions for Fairbanks and Kokee ================================================ Fairbanks and Kokee have VLBA backends, which can record in either VLBA ("v" or NDR=non-data replacement) or Mark4 ("m" or DR=data replacement) format. The VLBA formatters also have barrel roll capability. Only the VLBA format with barrel roll was tested in the CORRT test schedule. Therefore it was decided to record C3002 with Fairbanks and Kokee in VLBA format with roll. A short test of 3 additional scans was added to the end of the this session for Fairbanks, Kokee, and Westford. For these scans Fairbanks and Kokee will record in Mk4 format with roll. Fairbanks and Kokee should use FS 9.3.14 for this session to avoid having to hand edit the procedures for the test scans. Schedule ======== This schedule was made by C. Thomas using sked. Schedule setup parameters: Early start 20 sec (*) Minimum scan length 50 sec Maximum scan length 600 sec Minimum SNR 20 at X-band, margin of 5 15 at S-band, margin of 3 (*) It is anticipated that the time required at the correlator to synchronize tapes will decrease to just a few seconds. When that capability is available, the value of early start will be lowered. Automatic scheduling setup: optimize for uniform sky coverage at all stations, maximize the number of observations, minimize slewing time, minimize time between scans, consider the top 50% of ranked scans for selection, consider the last 3 hours of scans for sky coverage calculations, minimum 50 min between scans on the same source. The characteristics of the generated schedule are listed below. These will vary slightly for each schedule that is generated. The characteristics also will change when Ny Alesund is used in the network instead of Onsala. Schedule characteristics: Average scan length 112 seconds Average SNR 53.6 at X-band 36.2 at S-band Number of observations 2734 observations Average scans per station 319 scans Flux Information ================ Program snranal compares the measured performance of a session with respect to the predicted. The program calculates an empirical flux density for each source. In order to account for changes in the flux catalog since the last update based on source modeling, the fluxes in the flux catalog for the sources in the current source catalog were adjused using the following databases: Date Session ==== ========= 00FEB01 NEOS-A353 00FEB08 NEOS-A354 00FEB08 CORE-A081 00FEB22 NEOS-A356 00FEB29 NEOS-A357 00MAR14 NEOS-A359 00MAR21 NEOS-A360 00MAR28 NEOS-A361 00APR04 NEOS-A362 00APR11 NEOS-A363 Procedures ========== Please generate the procedures for this session using drudg. SKED Summary from file ./c3002.skd for experiment C3002 (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 x x x x x x x x x x I 17 49 8.1 0048-097Ix x x x x x x x x I 9 22 3.9 0059+581I x x xI 3 30 2.0 0106+013I x x x x x x x x x x x x x x x x x xI 18 63 9.0 0119+115Ix x x x x x x x x x x x x x x x x x x x x x xI 23 92 11.3 0119+041I x x x x x I 5 14 1.9 0229+131Ix x x x x I 5 18 2.1 0235+164I x x x x x x x x x x x x x I 13 62 7.2 CTA26 I x x x x x x x I 7 11 1.7 0458-020I x x x x x x x x x x x x x x x x x x I 18 56 8.6 0528+134Ix x x x x x x x x x x x x x x x x x x I 19 80 9.6 0552+398Ix x x x x x xx x x x x x xx x x x x x x x x x I 24 217 18.4 0556+238Ix x x x x x x x x x x x x xI 14 43 4.4 0718+793I x x x x x x x x x x I 10 18 1.2 0727-115I x xx x x x x x x x x x xx x x x I 17 44 9.0 0749+540I x x x x x x x x x x x x x x x x x x I 18 216 16.0 0804+499Ix x x x x I 5 70 5.7 0805+410I x I 1 3 .3 0823+033I xx x x x xx x x x x x x x x x x x x x xI 21 72 10.1 OJ287 I x x xx x x x x x x x x I 12 22 2.4 0919-260I x x x x x x I 6 12 5.9 0920-397I I 0 0 .0 4C39.25 I x x x x x x x x x x x x x x x x x x x x I 20 176 15.0 OK290 I x x I 2 2 .2 0955+476Ix x x x x x x x x x x x x x x x I 16 162 12.8 1044+719I x x x x x x x x x xI 10 90 6.2 1053+815I I 0 0 .0 1128+385I x x x x x x I 6 55 4.8 1219+044I xx x x x x x x x x x x x x x x x x x x xI 21 68 9.4 1300+580I x x x x x x I 6 52 3.9 1334-127Ix xx x x x x x x x x x x x x I 15 38 8.1 1351-018I xx x x x x x x x x x x x x x I 15 46 7.1 1357+769I x x x x x x x x xx x x I 12 180 12.0 1606+106I x x x x x x x x x x x x x x x x x x x x x xI 22 80 10.0 1622-253Ix x x x x x x x x x I 10 18 6.9 NRAO512 I x x x x x x x x x x I 10 84 6.9 1726+455I x x x x x x x x x x xI 11 13 .9 1739+522I x x x x x x x x x x x x I 12 109 8.0 1741-038I x x x x x x x x x x x x x x x x x x xI 19 60 9.5 1749+096I x x x x x x xI 7 41 5.2 1908-201I x x x x x x xI 7 22 7.0 1921-293I x x x I 3 3 1.3 1958-179Ix x x x x x I 6 11 3.1 2121+053I x x x x x x x x x x x x x x I 14 38 5.1 2128-123I x x x x x x x x I 8 18 4.2 2134+00 I x x x x x x x x xI 9 17 2.4 2145+067I x x x x x x x x x x x x xxI 14 66 8.7 2234+282I x x x x x x x x x x x x x x xI 15 65 6.5 2255-282Ixx x x x x I 6 6 2.5 Total scans, obs: 561 2734 Average number of obs. per baseline per source (normalized by up-time) = 6.4 Min = .0 Max = 30.6 (Baseline On-Wz on 0919-260) RMS = 6.9 Total time: 1428 minutes ( 23.8 hours). Key: Gc=GILCREEK Kk=KOKEE Ma=MATERA On=ONSALA60 Wf=WESTFORD Wz=WETTZELL Gc Kk Ma On Wf Wz Avg % obs. time: 36 42 42 44 46 37 41 % cal. time: 3 3 3 3 3 4 3 % slew time: 23 14 23 19 14 12 17 % idle time: 36 39 30 31 35 46 36 # of tapes : 1.1 1.2 1.2 1.3 1.4 1.1 total # scans: 339 281 327 313 304 350 319 # scans/hour : 14 11 13 13 12 14 13.3 Avg scan (sec): 92 130 111 123 130 91 112 # OF OBSERVATIONS BY BASELINE | Gc Kk Ma On Wf Wz StnTotal -------------------------------------- Gc|339 260 127 146 208 152 893 Kk| 281 56 76 170 73 635 Ma| 327 287 176 324 970 On| 313 185 303 997 Wf| 304 191 930 Wz| 350 1043 Number of 2-station scans: 152 Number of 3-station scans: 190 Number of 4-station scans: 97 Number of 5-station scans: 80 Number of 6-station scans: 42 Total # of scans, observations: 561 2734 Average baseline components for all observations Average XY = 4479. Average XZ = 3855. Average YZ = 2898. Average length = 4787.